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Landslide Susceptibility Assessment Using Frequency Ratio Technique with Iterative Random Sampling.

1. Introduction

Damage caused by natural hazards has been increasing due largely to residential expansion and population growth in many countries in the world [1-3]. Thus, government employees and researchers in those countries have been believed to be vulnerable to natural disasters and hence have studied hazard warning systems and hazard risk analyses in order to prevent the loss of lives and minimize the damage to property. In case of landslide hazards, high-risk landslide areas were identified and detected in the 1980s, and the landslide susceptibility analysis has been applied for the purpose of assessing the degree of risk in landslide-prone areas.

Over the past few decades, many researchers have contrived to develop efficient methods to create a reliable landslide susceptibility map. These approaches include frequency ratio [4-6], logistic regression [7, 8], decision trees [9-11], fuzzy logic [12-14], neurofuzzy systems [10, 15, 16], support vector machines [10,17-19], artificial neural networks [20-22], and multimethod approach [23-26].

Most studies on landslide susceptibility modeling (1) separated the training and validation data from given landslide location data through the random sampling approach, (2) created the landslide susceptibility map using the selected training data, and (3) calculated the accuracy of the landslide susceptibility map using the validation data. In those studies, the modeling procedure was applied just once and thus had inevitably fundamental weaknesses. That is, the outcomes obtained from the one-time modeling were most likely to be biased. For this reason, it is logically necessary to derive the landslide susceptibility maps through a well-established statistical approach via an iterative random sampling.

In essence, this paper assessed the performance of the landslide susceptibility analysis by way of frequency ratio (FR) with an iterative random sampling. The FR model has a key advantage that it is able to attain the rank of the causative factors with respect to a landslide occurrence as well as determine whether a given range of causative factor values will be threatening in the case of a landslide occurrence or not [27]. First, a pair of before-and-after digital aerial photographs with 50 cm spatial resolution was used to detect the occurrence of landslides in Yongin area, Korea. Then, a training and a validation dataset were iteratively random-sampled half and half from the detected landslide occurrences ten times. In each iteration, a landslide susceptibility map was generated from the training data by using the FR method and was validated from the validation data (Figure 1). Indeed, running FR modeling ten times enabled us to properly understand the regularized relationship between the causative factors and landslide susceptibility.

2. Mapping Landslides Using Aerial Photos

Mapping landslide occurrence areas is the first and foremost step to assess landslide susceptibility [28, 29]. One of the most common methods for landslide mapping is either a field survey or visual interpretation of stereoscopic aerial photography. However, these methods are not only time-consuming but also resource-intensive. What is more, they evidently require data for the extensive areas. So, the development of state-of-the-art remote sensing techniques is especially useful to detect landslide occurrence areas from high-resolution images [28, 30-34]. Most of all, a high-resolution digital aerial photograph can be used to produce a high-quality landslide inventory map through the visual interpretation of the aerial photographs with a field survey. This method has been employed as a principal source for landslide inventory map preparation [35-37].

Rainfall-triggered debris flows and shallow soil slide were both caused by intensive rainfall at Yongin area, Korea, in July 2011 (Figure 2). Landslide mappings of the study area were impossible with the field survey. Instead, high-resolution digital aerial photos were used for landslide mappings. In Korea, it is easy to download time-series digital aerial photos with 50 cm spatial resolution from a web portal (http://map.daum .net). The relevant photos were obtained biennially in 2008 and sky maps in 2012 were downloaded (http://www.skymaps .co.kr). The photos were taken from UltraCam X sensor (Microsoft, Graz, Austria) by Samah Aerial Survey Company (http://www.samah.com). The details of the UltraCam X instrument can be found in Lee et al. [38] and Gruber and Schneider [39].

For this research, the high-resolution photos were collected from Skymaps (http://www.skymaps.co.kr) and Daum (http://map.daum.net) portal sites. Because landslides occurred during the rainy season of 2011, both the preslide images in 2010 from Daum and the postslide photos taken in the same season in 2012 and 2014 from Skymaps were used. The photos were selected from each region of landslide occurrences. So, a total of eighteen photos were used and five ground control points (GCPs) were applied to each photo.

The photos were rectified via GCP from digital topographic features using ArcMap. The separation of landslides from tombs was a particularly demanding task in the study area. Thus, landslide locations were accurately detected by visual interpretation of the aerial photographs taken before and after landslide occurrences and then were checked in field investigations (Figures 3 and 4). Figures 3(a) and 4(a) are aerial photos prior to the July 27, 2017, landslide. Figure 3(a) shows tombs and a farmland and Figure 4(a) shows an elementary school and houses under the mountain. Figures 3(b), 3(c), 4(b), and 4(c) contain landslide scars. The debris barriers are clearly visible in Figures 3(d) and 4(d).

The majority of the rainfall-triggered debris flows have an approximate length of between 10 and 70 m constituting 60% of the study area. In Figures 3(b) and 4(b), the landslide reaches more than 100 m. The width ranges from 3 to 20 m. Most of the time, the depth is less than 1 m. The total number of landslide occurrences was eighty-two in the study area. Each location of landslide was denoted by a pixel of 5 m by 5 m and is shown in Figure 2. The training and validation datasets were randomly separated half and half from the landslide occurrence data. This random sampling was iteratively carried out ten times.

3. Construction of Predisposing Factors

Landslides and debris flows are controlled by the interaction of complex factors. Generally, shallow landslides occur during intense rainfalls due to elevated levels of soil moisture and low soil strength [40]. Topography affects the shallow landslide initiation through a gradient on the slope stability and concentration of a subsurface flow. Other predisposing factors include soil thickness and strength, rainfall direction, lithology, fracture, and root strength.

The preparations of thematic data layers were essential for a landslide susceptibility mapping (enhancing or mitigating) [41]. Although the above factors were important controls, in practice, spatial distribution of those factors was difficult to determine. However, digital topographic, soil, forest, and geological maps were obtainable. Accordingly, those attainable maps were collected for this work. The scale of all those maps was 1: 25,000 except for soil and forest maps with 1:5,000 (Table 1). And landslide-related topographic, hydrologic, soil, forest, and geologic factors can be used for the FR modeling. The factors are listed in Table 1 and spatial distributions of the factors are shown in Figures 5(a)-5(m). The factors had a 5 m x 5 m grid format. The dimensions of the study area were 1,760 columns by 1,090 rows for a total of 1,918,400 cells in Yongin area, Korea.

The topographic and hydrologic factors were prepared by a digital elevation model (DEM) which was derived from a triangulated irregular network (TIN) surface. The TIN was created from contour lines at 5 m intervals from digital topographic maps using ArcMap 10.2. Topographic and hydrologic factors such as slope gradient, plan curvature, slope aspect, midslope position (MSP), topographic position index (TPI), stream power index (SPI), and topographic wetness index (TWI) were taken into account for landslide susceptibility and calculated from DEM using SAGA GIS modules [42-45] (Figures 5(a)-5(g)). MSP and TPI with continuous value types were divided into ten equal areas in order to make a quantifiable comparison of a frequency ratio as per each factor per class. However, slope gradients were divided into nine classes, SPI was divided into six classes, and TWI was divided into nine classes since the specific values of these three factors cover more than 10% of the study area (Table 2).

Soil thickness, soil material, and topography factors from soil maps were examined for landslide susceptibility (Figures 5(h)-5(j)). The class of soil thickness from soil maps was divided into four classes: very shallow (<20 cm), shallow (20-50 cm), moderate (50-100 cm), and deep (>100 cm). Soil material includes three classes: gneiss, granite, and acidic. And topography is broken down into mountainous areas, fluvial plains, valley areas, hilly areas, alluvial fan areas, piedmont slope areas, and diluvium areas.

The timber diameter is divided into four classes (Figure 5(k)): very small (over 51% of area with <6cm), small (over 51% of area with <18 cm), medium (over 51% of area with <30 cm), and large (over 51% of area with >30 cm). The timber density is divided into three classes (Figure 5(l)): loose (less than 50% of a covered area), moderate (51~70%), and dense (over 71%).

Lithology (Figure 5(m)) in the study area consists of Alluvium (Qa), Granite Gneiss (PCEggn), Porphyroblastic Gneiss (PCEpgn), Quartzofeldspathic Gneiss (PCEqf), and Biotite Gneiss (PCEbgn). Biotite gneiss accounts for more than 60% of the study area.

In the landslide susceptibility assessment, it is important to check the multicollinearity of landslide causative factors. The tolerance and variance inflation factor (VIF) are well-established indexes for checking the multicollinearity. That a tolerance value is less than 0.1 or a VIF value exceeds 10 indicates a multicollinearity problem (Tien Bui et al., 2011). In this study, the tolerance and VIF values were calculated with the eighty-two landslide occurrences using SPSS software, and the results are shown in Table 2. The results indicate that there is no multicollinearity among the thirteen landslide causative factors.

4. Methods

The FR, as a leading probability model, is based on the observed spatial relationships between landslide causal factors and landslide occurrences. Consequently, the FR can be used to quantitatively assess the landslide susceptibility. The FR score for each range of factors was calculated (Table 2). More details of the FR score are found in Table 3. And then the landslide susceptibility index (LSI) was quantified by summation of each factor's FR score using the following equation [46]:

LSI = [summation] FRi, (1)

where LSI is landslide susceptibility index and FRi is the FR of each factor range or class.

Here, the FR represents that of the area where landslides occurred in the entire study area. Generally, a value of 1.0 is an average value. When the value is higher than 1.0, it means a higher correlation between landslide occurrences and their causal factors. On the other hand, when the value is lower than 1.0, it indicates a lower correlation between landslide occurrences and their causal factors.

5. Result

The tolerance and VIF values of thirteen causative factors were calculated to detect the multicollinearity problem. The maximum VIF and minimum tolerance were 8.49 and 0.11, respectively. Therefore, there was no multicollinearity between these factors (Table 2).

Slope gradients, SPI, and TWI with continuous values were divided into nine, six, and nine classes, respectively, since the specific value of these three factors covers more than 10% of the study area (Table 2).

As shown in Table 2, when a class of a factor has the FR value higher than 1.0, it may be assumed that the class is susceptible to a landslide. The FR trend of the slope degree factor showed a clear positive correlation. The classes with 18.45 to 62.53 slope degrees showed FR value almost higher than 1.0. In the case of plan curvature, the concave area with a 2.18 ratio was much more susceptible than the flat and convex area with 0.36 and 1.31 ratios, respectively. The east (E) and southeastern (SE) classes of the aspect factor had higher than 2.05 ratio values at all the estimates. The FR values of the MSP factor were higher than 1.0 in the 1st to the 4th classes. In the SPI factor, FR values higher than 1.0 are found in the 2nd to the 6th classes The FR values of the TWI were higher than 1.0 in the 1st, 2nd, and 5th classes.

The FR values of soil thickness greater than 20 cm and less than 100 cm were above 10. The FR values of the soil material and topography factors were higher than 1.3 in gneiss residuum and hilly areas classes. The FR values of timber diameter and density factors exceeded 1.0 in all areas except for the regions with no available data. In particular, the FR values of very small and small classes of diameter factors were above 5 while those of loose and moderate classes of density factors were above 3. In the lithology factor, the FR values were the highest in the biotite gneiss (PCEbgn) class.

A landslide susceptibilitymap should be able to effectively predict future landslide areas and it also ought to be validated by incorporating data from new landslide locations as they may occur. Therefore, the results from the landslide susceptibility analysis were confirmed by using the validation data. To approve each landslide susceptibility map, the calculated LSI values of all cells were sorted in a descending order. Next, the ordered cell values were divided into one hundred classes with cumulative 1% intervals. Additionally, the above procedure was adapted for the cells in which landslides had occurred by comparing the 100 classes in the study area. Then, a graph was made to compare the two sets of classifications.

To compare the results quantitatively, the areas under curves (AUCs) were recalculated as the total study area [47, 48]. The validation results showed 91.81%, 92.15%, 92.24%, 89.70%, 92.04%, 93.21%, 89.48%, 91.43%, 92.33%, and 91.77% for the 10 landslide susceptibility maps, each. The difference between the highest and lowest susceptibility accuracies was as small as 3.73%. The landslide susceptibility maps of the highest and lowest susceptibility accuracies are compared in Figure 6, and the success rate curves of them are shown in Figure 7. This means that the landslide susceptibility accuracy of the FR method is almost higher than 89%.

6. Conclusion and Discussion

In Korea, shallow landslides and debris flows have been caused by heavy rainfalls every single year. Accordingly, the landslide susceptibility mapping is instrumental in making a decision for the land use planning and urban development in Korea. Most studies for the landslide susceptibility modeling randomly sampled the training and validation data from the landslide occurrence data only once. However, those methods are highly dependent on the only one-time random-sampling step. So, this study performed the FR modeling with the 10 times iterative random sampling in order to properly understand the regularized relationship between the causative factors and the landslide susceptibility and then evaluated the performance of the landslide susceptibility analysis using the iterative FR modeling. The FR model can be used for the landslide susceptibility assessment because the landslide susceptibilities among classes in each landslide causative factor can be compared.

It is logically necessary to generate a qualified landslide inventory map in the landslide susceptibility assessment. The accuracy of landslide mappings is closely based on (1) the scale and quality of the aerial photographs or the satellite imagery, (2) the scale and quality of base or thematic maps, and (3) the interpreters' experience and skills. As the qualities of images, maps, and interpreters' skills get bettered, a margin of error for a landslide mapping will get decreased. Fortunately, time-series digital photos with the ground resolution of 50 cm have been provided in Korea every two years since 2008. The photos can be freely downloaded from the Daum and Skymap websites.

Even though landslide experts can detect landslide scars in photos, it is extremely hard to distinguish landslide scars from the tomb and its surrounding areas in the aerial photos due to close similarities. Nonetheless, with the help of visual comparison of before and after landslide photos and digital topographic maps, the landslide scars will be considerably easily distinguished from the tomb and its surrounding areas to improve the accuracy of the landslide scar identification.

Debris flows are typically controlled by the interaction of complex parameters such as intense rainfalls and topographic, hydrologic, soil, forest, and geological factors. However, it is particularly difficult to express the complex parameters in terms of spatial distribution. So, in this study, the landslide-related thirteen factors without multicollinearity among these factors were extracted from DEM, soil, forest, and geological maps in order to replace those complex parameters.

The landslide susceptibility was calculated according to the FR value in a class of each factor. If a class of a factor has the FR value of more than 1.0, the class must be susceptible to a landslide. As the slope degree increases, FR is higher in the slope classes of 18.45-21.80, 21.81-26.33, and 26.34-62.53. This means that when a slope gets higher, a landslide is more likely to occur. The landslide is more susceptible in the concave and convex areas than in the flat area. On average, 50 percent of landslides occurred in concaves areas, and 30 percent occurred in convex areas. This suggests that concave slopes are more vulnerable to shallow landslides due to running water concentration and the build-up of pore pressure [49]. Wind is also taken to be a crucial element which affects rainfall intensity on various slope aspects [50]. The landslide is highly susceptible on SE slope aspects. According to the data of Korea Meteorological Administration (KMA, http://web.kma.go.kr), the July 27, 2017, landslide was caused by the torrential rain. The then wind direction was reported to be almost SSE or SE. A most likely landslide initial location can be estimated based on MSP and TPI. MSP values are zero (e.g., midslope location) to one (e.g., valley or ridge with maximum vertical distance). Ridges and valleys have positive and negative TPI, respectively. Therefore, the risk of landslides gets higher in midslope to ridge where MSP value is below 0.47 and TPI value is above 1.0. As the catchment area enlarges and the slope gradient gets steeper, the amount of water influenced by upslope areas and the velocity of water flow will get increased. Accordingly, the SPI increases. The result of FR of SPI factors suggests that the region with the higher SPI has a higher risk of landslides. TWI has been used to describe the effect of topography on the location and size of saturated areas. The lower slope positions have a large catchment area and small slope angle; conversely, the upper slope positions have a small catchment area and high slope angle. The former has higher TWI and the latter has lower TWI. As a consequence, the areas with lower TWI are more prone to landslides in the study area.

Besides topological and hydrologic factors extracted from DEM, other factors also influence the spatial distribution of shallow landslide including soil thickness, soil strength, bedrock, and root strength (David and William, 1994). The landslide susceptibility was determined from FR values in their spatial distribution. Landslide typically occurred in hilly areas with 20-100 cm of soil depth and gneiss residuum. The forest factors related to strength of the root-soil bond restrict occurrences of a slope failure [51]. The large and dense timber usually tends to have strong roots and less landslide susceptibility. Consequently, this study confirms that when the FR of the area with the very small and loose timber is above 10, this area is more prone to landslides.

The results indicate a regularized relationship between the causative factors and the landslide susceptibility, which was obtained from the 10 times iterative modeling. Thus, the regularized relationship can be expansively used for a knowledge-driven landslide susceptibility mapping to other study areas. Moreover, it can also be applied for a threshold value of landslide early warning system.

The LSI was calculated by summation of each factor's FR score and then it carried out a landslide susceptibility assessment. The 10 landslide susceptibility maps were generated by the 10 times iterative frequency ratio modeling. The accuracy of the susceptibility maps was each 91.81%, 92.15%, 92.24%, 89.70%, 92.04%, 93.21%, 89.48%, 91.43%, 92.33%, and 91.77% from the 1st to the 10th iteration. The difference between the highest and their lowest accuracy was as small as 3.73%. Indeed, frequency ratio modeling with both random subsamples of high-resolution and high-quality data and high-scale maps confirmed their accuracy as high as 89%.

https://doi.org/10.1155/2017/3730913

Conflicts of Interest

The authors declare that they have no conflicts of interest.

Acknowledgments

This research was supported by the Basic Research Project

of the Korea Institute of Geoscience and Mineral Resources

(KIGAM) funded by the Ministry of Science, ICT and Future

Planning of Korea.

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[47] S. Lee and N. T. Dan, "Probabilistic landslide susceptibility mapping in the Lai Chau province of Vietnam: focus on the relationship between tectonic fractures and landslides," Environmental Geology, vol. 48, no. 6, pp. 778-787, 2005.

[48] S. Lee and T. Sambath, "Landslide susceptibility mapping in the Damrei Romel area, Cambodia using frequency ratio and logistic regression models," Environmental Geology, vol. 50, no. 6, pp. 847-855, 2006.

[49] C. Bartelletti, R. Giannecchini, G. D'Amato Avanzi, Y. Galanti, and A. Mazzali, "The influence of geological-morphological and land use settings on shallow landslides in the Pogliaschina T. basin (northern Apennines, Italy)," Journal of Maps, vol. 13, no. 2, pp. 142-152, 2017.

[50] J.-K. Liu and P. T. Y. Shih, "Topographic correction of Wind-Driven rainfall for landslide analysis in central Taiwan with validation from Aerial and satellite optical images," Remote Sensing, vol. 5, no. 6, pp. 2571-2589, 2013.

[51] K. M. Schmidt, J. J. Roering, J. D. Stock, W. E. Dietrich, D. R. Montgomery, and T. Schaub, "The variability of root cohesion as an influence on shallow landslide susceptibility in the Oregon Coast Range," Canadian Geotechnical Journal, vol. 38, no. 5, pp. 995-1024, 2001.

Hyun-Joo Oh, (1) Saro Lee, (2,3) and Soo-Min Hong (4)

(1) Geo-Environmental Hazards & Quaternary Geology Research Center, Korea Institute of Geoscience andMineral Resources (KIGAM), 124 Gwahang-no, Yuseong-gu, Daejeon 305-350, Republic of Korea

(2) Geological Research Center, Korea Institute of Geoscience and Mineral Resources (KIGAM), 124 Gwahang-no, Yuseong- gu, Daejeon 305-350, Republic of Korea

(3) Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 305-350, Republic of Korea

(4) Department of English Language and Literature, University of Seoul, 163 Seoulsiripdaero, Dongdaemun-gu, Seoul 02504, Republic of Korea

Correspondence should be addressed to Saro Lee; leesaro@kigam.re.kr and Soo-Min Hong; soomhong@uos.ac.kr

Received 17 April 2017; Revised 5 July 2017; Accepted 12 July 2017; Published 6 September 2017

Academic Editor: Eduard Llobet

Caption: FIGURE 1: Flowchart of the study procedures.

Caption: FIGURE 2: Digital aerial photograph with 82 landslide occurrences in the study area.

Caption: FIGURE 3: Digital aerial photographs (a) before and (b, c) after landslide occurrence and (d) the installed debris barrier after landslide occurrence in 2011.

Caption: FIGURE 4: Digital aerial photographs (a) before and (b, c) after landslide occurrence and (d) the installed debris barrier after landslide occurrence near an elementary school and houses in 2011.

Caption: FIGURE 5: Spatial database of the landslide causative factors.

Caption: FIGURE 6: Landslide susceptibility maps generated by the frequency ratio approach. The rank was classified into four classes based on the area for simple and visual interpretation: very high, high, medium, and low index ranges in 5%, 10%, 15%, and 70% of the study area, respectively: (a) 6th and (b) 7th susceptibility maps with the highest and lowest susceptibility accuracies, respectively.

Caption: FIGURE 7: Success rate curves of the 6th and 7th landslide susceptibility maps with the highest and lowest susceptibility accuracies.
TABLE 1: Data layer related to landslide of study area.

Category                             Factors

Topographic map   Topographic factors   Slope gradient Plan
                                          curvature Aspect
                                         Midslope position
                                         (MSP) Topographic
                                        position index (TPI)

Topographic map   Hydrologic factors     Stream power index
                                         (SPI) Topographic
                                        wetness index (TWI)

Soil map                                 Thickness Material
                                             Topography

Forest map                                Timber diameter
                                           Timber density

Geological map                               Lithology

Category          Data type    Scale            Source

Topographic map     Grid      1:25,000    National Geographic
                                         Information Institute
                                                (NGII)

Topographic map     Grid      1:25,000    National Geographic
                                         Information Institute
                                                (NGII)

Soil map           Polygon    1:5,000     National Academy of
                                         Agricultural Sciences
                                                (NAAS)

Forest map         Polygon    1:5,000    Korea Forest Research
                                           Institute (KFRI)

Geological map     Polygon    1:25,000    Korea Institute of
                                            Geoscience and
                                           Mineral Resources
                                                (KIGAM)

Table 2: The multicollinearity diagnosis indexes for factors and
frequency ratio (FR) values by 10 iterations of training data (TD)
(bold FR values mean 1 > of FR value; FR calculations are shown in
Table 3).

Factor                  Class          Tolerance   VIF     Number
                                                          of pixels

Slope                  0-4.52                              587838
gradient              4.53-7.26                            193369
                     7.27-11.30                            184261
                     11.31-15.79         0.14      6.94    199096
                     15.80-18.44                           185248
                     18.45-21.80                           196464
                     21.81-26.33                           182212
                     26.34-62.53                           189912

Plan curvature         Concave                             440473
                        Flat             0.74      1.35    1022631
                       Convex                              455296

Aspect                  Flat                               470201
                          N                                200803
                         NE                                171081
                          E                                145731
                         SE              0.71      1.42    160910
                          S                                178679
                         SW                                184698
                          W                                176440
                         NW                                229857

Midslope               0-0.13                              192836
position (MSP)        0.14-0.25                            192834
                      0.26-0.35                            192894
                      0.36-0.47                            192316
                      0.48-0.57          0.81      1.24    197554
                      0.58-0.67                            190370
                      0.68-0.77                            191273
                      0.78-0.83                            189560
                      0.84-0.90                            219546
                      0.91-1.00                            159217

Topographic        -28.29 to -5.52                         191895
position           -5.51 to -3.50                          191856
index (TPI)        -3.49 to -2.16                          191884
                   -2.15 to -1.15        0.54      1.85    191913
                   -1.14 to -0.40                          191973
                     -0.39-0.00                            222180
                      0.01-1.00                            184177
                      1.01-3.43                            184220
                      3.44-7.28                            184167
                     7.29-30.27                            184135

Stream power           0-0.30                              956705
index (SPI)           0.31-0.64                            195189
                      0.65-1.08          0.14      7.02    191396
                      1.09-1.59                            191237
                      1.60-2.34                            191242
                     2.35-12.74                            192631

Topographic           4.43-5.47                            195462
wetness               5.48-5.67                            187422
index (TWI)           5.68-5.86                            198082
                      5.87-6.07                            187444
                      6.08-6.35          0.11      8.49    191019
                      6.36-6.73                            192213
                      6.74-7.19                            192409
                      7.20-7.66                            191741
                    7.67-no data                           382608

Soil thickness           <20                               269442
(unit: cm)              20-50                              184425
                       50-100            0.81      1.24    940929
                        >100                               451703
                       No data                              71901

Soil material      Gneiss residuum                         1076813
                  Granite Residuum       0.57      1.74    128052
                   Acidic Residuum                         433895
                        River                              207739
                       No data                              71901

Topography        Mountainous area                         650359
                 Fluvial plains area                       202488
                     Valley area                           405521
                     Hilly area                            465206
                  Alluvial fan area      0.67      1.50     35874
                 Piedmont slope area                        81800
                    Diluvium area                           5251
                       No data                              71901

Timber               Very small                             35455
diameter                Small                              100945
                       Medium            0.13      7.57    861368
                        Large                               33512
                       No data                             887120

Timber                  Loose                               39728
density               Moderate           0.13      7.57    118023
                        Dense                              873529
                       No data                             887120

Lithology                Qa                                403382
                       PCEggn                               1946
                       PCEpgn            0.96      1.04     13277
                        PCEqf                              257984
                       PCEbgn                              1241811

Factor                  Class           %of    FR by    FR by
                                       class   1st TD   2nd TD

Slope                  0-4.52          30.64    0.08     0.00
gradient              4.53-7.26        10.08    0.48     0.48
                     7.27-11.30        9.60     0.00     0.25
                     11.31-15.79       10.38    0.71     0.47
                     15.80-18.44       9.66     0.25     0.76
                     18.45-21.80       10.24    1.67     1.67
                     21.81-26.33       9.50     2.82     2.05
                     26.34-62.53       9.90     3.94     4.43

Plan curvature         Concave         22.96    2.55     2.34
                        Flat           53.31    0.23     0.23
                       Convex          23.73    1.23     1.44

Aspect                  Flat           24.51    0.00     0.00
                          N            10.47    0.47     0.70
                         NE            8.92     1.37     0.82
                          E            7.60     2.25     1.93
                         SE            8.39     4.07     4.07
                          S            9.31     1.05     0.52
                         SW            9.63     0.51     0.25
                          W            9.20     0.53     1.59
                         NW            11.98    1.02     1.22

Midslope               0-0.13          10.05    1.46     1.21
position (MSP)        0.14-0.25        10.05    2.18     1.94
                      0.26-0.35        10.05    1.70     1.70
                      0.36-0.47        10.02    0.97     0.97
                      0.48-0.57        10.30    0.95     0.95
                      0.58-0.67        9.92     0.74     0.98
                      0.68-0.77        9.97     0.73     0.98
                      0.78-0.83        9.88     0.74     0.74
                      0.84-0.90        11.44    0.21     0.21
                      0.91-1.00        8.30     0.29     0.29

Topographic        -28.29 to -5.52     10.00    0.98     0.73
position           -5.51 to -3.50      10.00    0.49     0.98
index (TPI)        -3.49 to -2.16      10.00    0.49     0.73
                   -2.15 to -1.15      10.00    0.24     0.49
                   -1.14 to -0.40      10.01    0.24     0.24
                     -0.39-0.00        11.58    0.21     0.21
                      0.01-1.00        9.60     1.27     0.51
                      1.01-3.43        9.60     1.52     1.52
                      3.44-7.28        9.60     2.79     2.54
                     7.29-30.27        9.60     2.03     2.29

Stream power           0-0.30          49.87    0.34     0.49
index (SPI)           0.31-0.64        10.17    0.96     0.96
                      0.65-1.08        9.98     1.71     1.47
                      1.09-1.59        9.97     1.71     2.20
                      1.60-2.34        9.97     1.96     1.47
                     2.35-12.74        10.04    1.94     1.46

Topographic           4.43-5.47        10.19    5.51     5.03
wetness               5.48-5.67        9.77     2.25     2.00
index (TWI)           5.68-5.86        10.33    0.24     1.18
                      5.87-6.07        9.77     1.00     0.50
                      6.08-6.35        9.96     0.98     0.98
                      6.36-6.73        10.02    0.00     0.24
                      6.74-7.19        10.03    0.00     0.00
                      7.20-7.66        9.99     0.00     0.00
                    7.67-no data       19.94    0.00     0.00

Soil thickness           <20           14.05    0.35     0.35
(unit: cm)              20-50          9.61     1.52     1.78
                       50-100          49.05    1.24     1.14
                        >100           23.55    0.83     0.93
                       No data         3.75     0.00     0.00

Soil material      Gneiss residuum     56.13    1.35     1.26
                  Granite Residuum     6.67     0.37     0.73
                   Acidic Residuum     22.62    0.75     0.97
                        River          10.83    0.45     0.23
                       No data         3.75     0.00     0.00

Topography        Mountainous area     33.90    0.58     0.79
                 Fluvial plains area   10.56    0.46     0.23
                     Valley area       21.14    0.92     1.15
                     Hilly area        24.25    2.31     1.81
                  Alluvial fan area    1.87     0.00     0.00
                 Piedmont slope area   4.26     0.00     0.57
                    Diluvium area      0.27     0.00     0.00
                       No data         3.75     0.00     0.00

Timber               Very small        1.85    10.56    11.88
diameter                Small          5.26     5.56     5.56
                       Medium          44.90    1.03     1.03
                        Large          1.75     2.79     1.40
                       No data         46.24    0.00     0.00

Timber                  Loose          2.07     9.42    10.60
density               Moderate         6.15     2.78     3.17
                        Dense          45.53    1.39     1.29
                       No data         46.24    0.00     0.00

Lithology                Qa            21.03    0.23     0.12
                       PCEggn          0.10     0.00     0.00
                       PCEpgn          0.69     0.00     0.00
                        PCEqf          13.45    0.00     0.00
                       PCEbgn          64.73    1.47     1.51

Factor                  Class          FR by    FR by    FR by
                                       3rd TD   4th TD   5th TD

Slope                  0-4.52           0.00     0.08     0.08
gradient              4.53-7.26         0.48     0.24     0.48
                     7.27-11.30         0.51     0.00     0.25
                     11.31-15.79        0.47     0.71     0.47
                     15.80-18.44        0.76     0.25     0.51
                     18.45-21.80        1.91     1.43     1.67
                     21.81-26.33        1.80     2.31     2.31
                     26.34-62.53        4.19     4.93     4.19

Plan curvature         Concave          2.12     2.44     2.44
                        Flat            0.50     0.27     0.46
                       Convex           1.03     1.23     0.82

Aspect                  Flat            0.00     0.00     0.00
                          N             0.93     0.70     0.47
                         NE             1.09     1.37     1.09
                          E             2.89     1.61     1.61
                         SE             2.91     4.07     4.65
                          S             0.79     1.05     1.05
                         SW             0.76     0.51     0.25
                          W             0.80     0.80     0.80
                         NW             1.02     1.02     1.22

Midslope               0-0.13           1.70     0.97     1.46
position (MSP)        0.14-0.25         1.94     2.43     2.43
                      0.26-0.35         1.46     2.18     1.46
                      0.36-0.47         1.22     1.22     0.73
                      0.48-0.57         0.71     0.47     0.71
                      0.58-0.67         0.74     0.74     0.74
                      0.68-0.77         0.73     1.22     0.98
                      0.78-0.83         1.23     0.25     1.23
                      0.84-0.90         0.21     0.21     0.21
                      0.91-1.00         0.00     0.29     0.00

Topographic        -28.29 to -5.52      0.98     0.73     0.98
position           -5.51 to -3.50       0.98     0.49     0.98
index (TPI)        -3.49 to -2.16       0.24     0.98     0.24
                   -2.15 to -1.15       0.49     0.49     0.49
                   -1.14 to -0.40       0.00     0.24     0.00
                     -0.39-0.00         0.21     0.00     0.21
                      0.01-1.00         1.27     0.76     0.76
                      1.01-3.43         1.27     1.78     2.03
                      3.44-7.28         2.79     3.05     2.54
                     7.29-30.27         2.03     1.78     2.03

Stream power           0-0.30           0.34     0.29     0.34
index (SPI)           0.31-0.64         1.20     1.44     1.20
                      0.65-1.08         2.20     1.47     1.22
                      1.09-1.59         1.22     2.45     1.71
                      1.60-2.34         1.22     1.47     1.96
                     2.35-12.74         2.43     1.70     2.19

Topographic           4.43-5.47         5.51     5.27     4.31
wetness               5.48-5.67         2.00     3.00     2.75
index (TWI)           5.68-5.86         0.24     0.24     0.47
                      5.87-6.07         0.50     0.25     0.75
                      6.08-6.35         1.47     1.22     1.47
                      6.36-6.73         0.24     0.00     0.24
                      6.74-7.19         0.00     0.00     0.00
                      7.20-7.66         0.00     0.00     0.00
                    7.67-no data        0.00     0.00     0.00

Soil thickness           <20            0.52     0.35     0.35
(unit: cm)              20-50           1.52     1.27     2.03
                       50-100           1.24     1.24     1.19
                        >100            0.73     0.93     0.73
                       No data          0.00     0.00     0.00

Soil material      Gneiss residuum      1.35     1.26     1.35
                  Granite Residuum      0.73     0.73     0.73
                   Acidic Residuum      0.65     0.97     0.75
                        River           0.45     0.23     0.23
                       No data          0.00     0.00     0.00

Topography        Mountainous area      0.72     0.58     0.86
                 Fluvial plains area    0.46     0.23     0.23
                     Valley area        0.81     1.27     0.92
                     Hilly area         2.11     2.11     1.91
                  Alluvial fan area     0.00     0.00     0.00
                 Piedmont slope area    0.57     0.00     0.57
                    Diluvium area       0.00     0.00     0.00
                       No data          0.00     0.00     0.00

Timber               Very small        10.56    11.88    11.88
diameter                Small           4.64     5.56     6.03
                       Medium           1.25     1.03     0.98
                        Large           0.00     1.40     1.40
                       No data          0.00     0.00     0.00

Timber                  Loose           9.42    12.96    10.60
density               Moderate          3.17     3.57     2.78
                        Dense           1.34     1.23     1.34
                       No data          0.00     0.00     0.00

Lithology                Qa             0.12     0.23     0.12
                       PCEggn           0.00     0.00     0.00
                       PCEpgn           0.00     0.00     0.00
                        PCEqf           0.00     0.00     0.00
                       PCEbgn           1.51     1.47     1.51

Factor                  Class          FR by    FR by    FR by
                                       6th TD   7th TD   8th TD

Slope                  0-4.52           0.08     0.08     0.08
gradient              4.53-7.26         0.24     0.00     0.24
                     7.27-11.30         0.51     0.25     0.51
                     11.31-15.79        0.24     0.47     0.47
                     15.80-18.44        0.76     0.25     0.76
                     18.45-21.80        1.67     1.43     1.43
                     21.81-26.33        2.57     2.57     2.31
                     26.34-62.53        3.94     4.93     4.19

Plan curvature         Concave          2.02     1.81     1.59
                        Flat            0.32     0.32     0.41
                       Convex           1.54     1.75     1.75

Aspect                  Flat            0.00     0.00     0.00
                          N             0.93     0.70     0.93
                         NE             0.82     0.55     1.37
                          E             2.57     2.25     1.28
                         SE             3.20     4.07     3.78
                          S             1.31     0.79     1.05
                         SW             0.25     1.01     1.27
                          W             0.80     1.59     0.80
                         NW             1.22     0.41     0.61

Midslope               0-0.13           1.21     1.70     1.21
position (MSP)        0.14-0.25         2.43     2.67     2.67
                      0.26-0.35         1.46     1.21     1.70
                      0.36-0.47         1.46     0.73     1.46
                      0.48-0.57         0.95     1.18     0.95
                      0.58-0.67         0.98     1.47     0.49
                      0.68-0.77         0.49     0.24     0.49
                      0.78-0.83         0.99     0.49     0.49
                      0.84-0.90         0.00     0.00     0.21
                      0.91-1.00         0.00     0.29     0.29

Topographic        -28.29 to -5.52      0.98     0.73     0.73
position           -5.51 to -3.50       0.73     0.49     0.73
index (TPI)        -3.49 to -2.16       0.49     0.49     0.49
                   -2.15 to -1.15       0.24     0.24     0.24
                   -1.14 to -0.40       0.24     0.00     0.49
                     -0.39-0.00         0.21     0.00     0.00
                      0.01-1.00         0.76     1.27     1.02
                      1.01-3.43         2.03     2.29     2.03
                      3.44-7.28         2.29     2.54     2.79
                     7.29-30.27         2.29     2.29     1.78

Stream power           0-0.30           0.44     0.39     0.39
index (SPI)           0.31-0.64         0.48     1.44     1.20
                      0.65-1.08         1.71     0.98     1.47
                      1.09-1.59         1.96     2.45     2.94
                      1.60-2.34         1.96     1.96     1.47
                     2.35-12.74         1.70     1.21     0.97

Topographic           4.43-5.47         4.31     5.51     4.55
wetness               5.48-5.67         3.25     2.50     2.75
index (TWI)           5.68-5.86         0.71     0.94     0.47
                      5.87-6.07         0.25     0.25     1.00
                      6.08-6.35         1.22     0.73     0.98
                      6.36-6.73         0.24     0.00     0.24
                      6.74-7.19         0.00     0.00     0.00
                      7.20-7.66         0.00     0.00     0.00
                    7.67-no data        0.00     0.00     0.00

Soil thickness           <20            0.17     0.17     0.35
(unit: cm)              20-50           2.03     1.01     1.78
                       50-100           1.14     1.44     1.19
                        >100            0.93     0.73     0.83
                       No data          0.00     0.00     0.00

Soil material      Gneiss residuum      1.26     1.43     1.26
                  Granite Residuum      0.73     1.10     1.10
                   Acidic Residuum      0.97     0.54     0.86
                        River           0.23     0.00     0.23
                       No data          0.00     0.00     0.00

Topography        Mountainous area      0.94     0.79     0.86
                 Fluvial plains area    0.23     0.00     0.23
                     Valley area        1.15     0.92     1.15
                     Hilly area         1.61     2.21     1.71
                  Alluvial fan area     0.00     0.00     0.00
                 Piedmont slope area    0.57     0.00     0.57
                    Diluvium area       0.00     0.00     0.00
                       No data          0.00     0.00     0.00

Timber               Very small        11.88     9.24    14.52
diameter                Small           5.10     6.49     5.10
                       Medium           1.09     0.98     0.92
                        Large           1.40     2.79     2.79
                       No data          0.00     0.00     0.00

Timber                  Loose          10.60     8.24    12.96
density               Moderate          3.17     4.36     2.78
                        Dense           1.29     1.23     1.23
                       No data          0.00     0.00     0.00

Lithology                Qa             0.12     0.35     0.35
                       PCEggn           0.00     0.00     0.00
                       PCEpgn           0.00     0.00     0.00
                        PCEqf           0.00     0.00     0.00
                       PCEbgn           1.51     1.43     1.43

Factor                  Class          FR by     FR by    Min. of
                                       9th TD   10th TD     FR

Slope                  0-4.52           0.08     0.08      0.00
gradient              4.53-7.26         0.00     0.48      0.00
                     7.27-11.30         0.00     0.51      0.00
                     11.31-15.79        0.71     0.24      0.24
                     15.80-18.44        1.01     0.51      0.25
                     18.45-21.80        1.43     2.14      1.43
                     21.81-26.33        3.08     2.31      1.80
                     26.34-62.53        3.70     3.70      3.70

Plan curvature         Concave          2.44     2.02      1.59
                        Flat            0.32     0.50      0.23
                       Convex           1.13     1.13      0.82

Aspect                  Flat            0.00     0.00      0.00
                          N             0.93     1.17      0.47
                         NE             0.82     0.82      0.55
                          E             2.57     1.61      1.28
                         SE             3.78     3.49      2.91
                          S             0.79     0.79      0.52
                         SW             0.76     0.76      0.25
                          W             0.80     1.06      0.53
                         NW             0.81     1.22      0.41

Midslope               0-0.13           1.94     0.73      0.73
position (MSP)        0.14-0.25         1.70     2.43      1.70
                      0.26-0.35         1.94     1.21      1.21
                      0.36-0.47         1.22     1.46      0.73
                      0.48-0.57         0.71     0.71      0.47
                      0.58-0.67         1.23     1.23      0.49
                      0.68-0.77         0.49     0.73      0.24
                      0.78-0.83         0.74     0.99      0.25
                      0.84-0.90         0.00     0.21      0.00
                      0.91-1.00         0.00     0.29      0.00

Topographic        -28.29 to -5.52      0.73     0.98      0.73
position           -5.51 to -3.50       0.49     0.73      0.49
index (TPI)        -3.49 to -2.16       0.49     0.49      0.24
                   -2.15 to -1.15       0.24     0.24      0.24
                   -1.14 to -0.40       0.24     0.24      0.00
                     -0.39-0.00         0.21     0.00      0.00
                      0.01-1.00         0.51     0.76      0.51
                      1.01-3.43         2.03     2.54      1.27
                      3.44-7.28         3.05     2.54      2.29
                     7.29-30.27         2.29     1.78      1.78

Stream power           0-0.30           0.49     0.39      0.29
index (SPI)           0.31-0.64         1.20     0.96      0.48
                      0.65-1.08         0.98     2.20      0.98
                      1.09-1.59         1.96     2.20      1.22
                      1.60-2.34         2.20     1.71      1.22
                     2.35-12.74         1.21     0.97      0.97

Topographic           4.43-5.47         5.03     4.79      4.31
wetness               5.48-5.67         1.75     2.25      1.75
index (TWI)           5.68-5.86         0.94     0.71      0.24
                      5.87-6.07         1.25     0.75      0.25
                      6.08-6.35         0.98     1.22      0.73
                      6.36-6.73         0.00     0.24      0.00
                      6.74-7.19         0.00     0.00      0.00
                      7.20-7.66         0.00     0.00      0.00
                    7.67-no data        0.00     0.00      0.00

Soil thickness           <20            0.00     0.17      0.00
(unit: cm)              20-50           1.27     1.78      1.01
                       50-100           1.49     1.29      1.14
                        >100            0.62     0.73      0.62
                       No data          0.00     0.00      0.00

Soil material      Gneiss residuum      1.39     1.35      1.26
                  Granite Residuum      0.73     0.37      0.37
                   Acidic Residuum      0.65     0.97      0.54
                        River           0.23     0.00      0.00
                       No data          0.00     0.00      0.00

Topography        Mountainous area      0.79     0.79      0.58
                 Fluvial plains area    0.23     0.00      0.00
                     Valley area        0.92     1.04      0.81
                     Hilly area         2.11     2.01      1.61
                  Alluvial fan area     0.00     0.00      0.00
                 Piedmont slope area    0.00     0.57      0.00
                    Diluvium area       0.00     0.00      0.00
                       No data          0.00     0.00      0.00

Timber               Very small        10.56     11.88     9.24
diameter                Small           5.56     6.03      4.64
                       Medium           1.09     0.98      0.92
                        Large           1.40     1.40      0.00
                       No data          0.00     0.00      0.00

Timber                  Loose           9.42     10.60     8.24
density               Moderate          2.78     4.76      2.78
                        Dense           1.39     1.07      1.07
                       No data          0.00     0.00      0.00

Lithology                Qa             0.00     0.00      0.00
                       PCEggn           0.00     0.00      0.00
                       PCEpgn           0.00     0.00      0.00
                        PCEqf           0.00     0.00      0.00
                       PCEbgn           1.54     1.54      1.43

Factor                  Class          Max. of   Mean of
                                         FR        FR

Slope                  0-4.52           0.08      0.06
gradient              4.53-7.26         0.48      0.31
                     7.27-11.30         0.51      0.28
                     11.31-15.79        0.71      0.50
                     15.80-18.44        1.01      0.58
                     18.45-21.80        2.14      1.65
                     21.81-26.33        3.08      2.41
                     26.34-62.53        4.93      4.21

Plan curvature         Concave          2.55      2.18
                        Flat            0.50      0.36
                       Convex           1.75      1.31

Aspect                  Flat            0.00      0.00
                          N             1.17      0.79
                         NE             1.37      1.01
                          E             2.89      2.05
                         SE             4.65      3.81
                          S             1.31      0.92
                         SW             1.27      0.63
                          W             1.59      0.95
                         NW             1.22      0.98

Midslope               0-0.13           1.94      1.36
position (MSP)        0.14-0.25         2.67      2.28
                      0.26-0.35         2.18      1.60
                      0.36-0.47         1.46      1.14
                      0.48-0.57         1.18      0.83
                      0.58-0.67         1.47      0.93
                      0.68-0.77         1.22      0.71
                      0.78-0.83         1.23      0.79
                      0.84-0.90         0.21      0.15
                      0.91-1.00         0.29      0.18

Topographic        -28.29 to -5.52      0.98      0.85
position           -5.51 to -3.50       0.98      0.71
index (TPI)        -3.49 to -2.16       0.98      0.51
                   -2.15 to -1.15       0.49      0.34
                   -1.14 to -0.40       0.49      0.19
                     -0.39-0.00         0.21      0.13
                      0.01-1.00         1.27      0.89
                      1.01-3.43         2.54      1.90
                      3.44-7.28         3.05      2.69
                     7.29-30.27         2.29      2.06

Stream power           0-0.30           0.49      0.39
index (SPI)           0.31-0.64         1.44      1.10
                      0.65-1.08         2.20      1.54
                      1.09-1.59         2.94      2.08
                      1.60-2.34         2.20      1.74
                     2.35-12.74         2.43      1.58

Topographic           4.43-5.47         5.51      4.98
wetness               5.48-5.67         3.25      2.45
index (TWI)           5.68-5.86         1.18      0.61
                      5.87-6.07         1.25      0.65
                      6.08-6.35         1.47      1.13
                      6.36-6.73         0.24      0.14
                      6.74-7.19         0.00      0.00
                      7.20-7.66         0.00      0.00
                    7.67-no data        0.00      0.00

Soil thickness           <20            0.52      0.28
(unit: cm)              20-50           2.03      1.60
                       50-100           1.49      1.26
                        >100            0.93      0.80
                       No data          0.00      0.00

Soil material      Gneiss residuum      1.43      1.33
                  Granite Residuum      1.10      0.73
                   Acidic Residuum      0.97      0.81
                        River           0.45      0.23
                       No data          0.00      0.00

Topography        Mountainous area      0.94      0.77
                 Fluvial plains area    0.46      0.23
                     Valley area        1.27      1.03
                     Hilly area         2.31      1.99
                  Alluvial fan area     0.00      0.00
                 Piedmont slope area    0.57      0.34
                    Diluvium area       0.00      0.00
                       No data          0.00      0.00

Timber               Very small         14.52     11.48
diameter                Small           6.49      5.56
                       Medium           1.25      1.04
                        Large           2.79      1.68
                       No data          0.00      0.00

Timber                  Loose           12.96     10.48
density               Moderate          4.76      3.33
                        Dense           1.39      1.28
                       No data          0.00      0.00

Lithology                Qa             0.35      0.16
                       PCEggn           0.00      0.00
                       PCEpgn           0.00      0.00
                        PCEqf           0.00      0.00
                       PCEbgn           1.54      1.49

Number of training data: 41 landslide occurrences. Abbreviations
of Lithobgy. Qa: Alluvium; PCEggn: Granite Gneiss; PCEpgn:
Porphyroblastic Gneiss; PCEqf: Quartzofeldspathic Gneiss; PCEbgn:
Biotite Gneiss.

Table 3: Frequency ratio (FR) values by iterations of training data
(TD) (bold FR values mean 1 > of FR value).

Factor                     Class            Number     %of
                                              of      class
                                            pixels

Gradient                  0-4.52            587838    30.64
                         4.53-7.26          193369    10.08
                        7.27-11.30          184261    9.60
                        11.31-15.79         199096    10.38
                        15.80-18.44         185248    9.66
                        18.45-21.80         196464    10.24
                        21.81-26.33         182212    9.50
                        26.34-62.53         189912    9.90

                          Concave           440473    22.96
Plan curvature             Flat             1022631   53.31
                          Convex            455296    23.73

Aspect                     Flat             470201    24.51
                             N              200803    10.47
                            NE              171081    8.92
                             E              145731    7.60
                            SE              160910    8.39
                             S              178679    9.31
                            SW              184698    9.63
                             W              176440    9.20
                            NW              229857    11.98

Midslope                  0-0.13            192836    10.05
position (MSP)           0.14-0.25          192834    10.05
                         0.26-0.35          192894    10.05
                         0.36-0.47          192316    10.02
                         0.48-0.57          197554    10.30
                         0.58-0.67          190370    9.92
                         0.68-0.77          191273    9.97
                         0.78-0.83          189560    9.88
                         0.84-0.90          219546    11.44
                         0.91-1.00          159217    8.30

Topographic           -28.29 to -5.52       191895    10.00
position index        -5.51 to -3.50        191856    10.00
(TPI)                 -3.49 to -2.16        191884    10.00
                      -2.15 to -1.15        191913    10.00
                      -1.14 to -0.40        191973    10.01
                        -0.39-0.00          222180    11.58
                         0.01-1.00          184177    9.60
                         1.01-3.43          184220    9.60
                         3.44-7.28          184167    9.60
                        7.29-30.27          184135    9.60

Stream power              0-0.30            956705    49.87
index (SPI)              0.31-0.64          195189    10.17
                         0.65-1.08          191396    9.98
                         1.09-1.59          191237    9.97
                         1.60-2.34          191242    9.97
                        2.35-12.74          192631    10.04

Topographic              4.43-5.47          195462    10.19
wetness index            5.48-5.67          187422    9.77
(TWI)                    5.68-5.86          198082    10.33
                         5.87-6.07          187444    9.77
                         6.08-6.35          191019    9.96
                         6.36-6.73          192213    10.02
                         6.74-7.19          192409    10.03
                         7.20-7.66          191741    9.99
                       7.67-no data         382608    19.94

Soil thickness              <20             269442    14.05
(unit: cm)                 20-50            184425    9.61
                          50-100            940929    49.05
                           >100             451703    23.55
                          No data            71901    3.75

Soil material         Gneiss residuum       1076813   56.13
                  Granite residuum Acidic   128052    6.67
                         residuum           433895    22.62
                           River            207739    10.83
                          No data            71901    3.75

Topography           Mountainous area       650359    33.90
                    Fluvial plains area     202488    10.56
                        Valley area         405521    21.14
                        Hilly area          465206    24.25
                     Alluvial fan area       35874    1.87
                    Piedmont slope area      81800    4.26
                       Diluvium area         5251     0.27
                          No data            71901    3.75

Timber diameter         Very small           35455    1.85
                           Small            100945    5.26
                          Medium            861368    44.90
                           Large             33512    1.75
                          No data           887120    46.24

Timber density             Loose             39728    2.07
                         Moderate           118023    6.15
                           Dense            873529    45.53
                          No data           887120    46.24

Lithology                   Qa              403382    21.03
                          PCEggn             1946     0.10
                          PCEpgn             13277    0.69
                           PCEqf            257984    13.45
                          PCEbgn            1241811   64.73

Gradient                  0-4.52            587838    30.64
                         4.53-7.26          193369    10.08
                        7.27-11.30          184261    9.60
                        11.31-15.79         199096    10.38
                        15.80-18.44         185248    9.66
                        18.45-21.80         196464    10.24
                        21.81-26.33         182212    9.50
                        26.34-62.53         189912    9.90

Plan curvature            Concave           440473    22.96
                           Flat             1022631   53.31
                          Convex            455296    23.73

Aspect                     Flat             470201    24.51
                             N              200803    10.47
                            NE              171081    8.92
                             E              145731    7.60
                            SE              160910    8.39
                             S              178679    9.31
                            SW              184698    9.63
                             W              176440    9.20
                            NW              229857    11.98

Midslope                  0-0.13            192836    10.05
position (MSP)           0.14-0.25          192834    10.05
                         0.26-0.35          192894    10.05
                         0.36-0.47          192316    10.02
                         0.48-0.57          197554    10.30
                         0.58-0.67          190370    9.92
                         0.68-0.77          191273    9.97
                         0.78-0.83          189560    9.88
                         0.84-0.90          219546    11.44
                         0.91-1.00          159217    8.30

Topographic           -28.29 to -5.52       191895    10.00
position              -5.51 to -3.50        191856    10.00
index (TPI)           -3.49 to -2.16        191884    10.00
                      -2.15 to -1.15        191913    10.00
                      -1.14 to -0.40        191973    10.01
                        -0.39-0.00          222180    11.58
                         0.01-1.00          184177    9.60
                         1.01-3.43          184220    9.60
                         3.44-7.28          184167    9.60
                        7.29-30.27          184135    9.60

Stream power              0-0.30            956705    49.87
index (SPI)              0.31-0.64          195189    10.17
                         0.65-1.08          191396    9.98
                         1.09-1.59          191237    9.97
                         1.60-2.34          191242    9.97
                        2.35-12.74          192631    10.04

Topographic              4.43-5.47          195462    10.19
wetness index            5.48-5.67          187422    9.77
(TWI)                    5.68-5.86          198082    10.33
                         5.87-6.07          187444    9.77
                         6.08-6.35          191019    9.96
                         6.36-6.73          192213    10.02
                         6.74-7.19          192409    10.03
                         7.20-7.66          191741    9.99
                       7.67-no data         382608    19.94

Soil thickness              <20             269442    14.05
(unit: cm)                 20-50            184425    9.61
                          50-100            940929    49.05
                           >100             451703    23.55
                          No data            71901    3.75

Soil material         Gneiss residuum       1076813   56.13
                     Granite residuum       128052    6.67
                      Acidic residuum       433895    22.62
                           River            207739    10.83
                          No data            71901    3.75

Topography           Mountainous area       650359    33.90
                    Fluvial plains area     202488    10.56
                        Valley area         405521    21.14
                        Hilly area          465206    24.25
                     Alluvial fan area       35874    1.87
                    Piedmont slope area      81800    4.26
                       Diluvium area         5251     0.27
                          No data            71901    3.75

Timber diameter         Very small           35455    1.85
                           Small            100945    5.26
                          Medium            861368    44.90
                           Large             33512    1.75
                          No data           887120    46.24

Timber density             Loose             39728    2.07
                         Moderate           118023    6.15
                           Dense            873529    45.53
                          No data           887120    46.24

Lithology                   Qa              403382    21.03
                          PCEggn             1946     0.10
                          PCEpgn             13277    0.69
                           PCEqf            257984    13.45
                          PCEbgn            1241811   64.73

                                                     1st TD

Factor                     Class              Number        %of
                                                of       landslide
                                            landslides

Gradient                  0-4.52                1          2.44
                         4.53-7.26              2          4.88
                        7.27-11.30              0          0.00
                        11.31-15.79             3          7.32
                        15.80-18.44             1          2.44
                        18.45-21.80             7          17.07
                        21.81-26.33             11         26.83
                        26.34-62.53             16         39.02

                          Concave               24         58.54
Plan curvature             Flat                 5          12.20
                          Convex                12         29.27

Aspect                     Flat                 0            0
                             N                  2          4.88
                            NE                  5          12.20
                             E                  7          17.07
                            SE                  14         34.15
                             S                  4          9.76
                            SW                  2          4.88
                             W                  2          4.88
                            NW                  5          12.20

Midslope                  0-0.13                6          14.63
position (MSP)           0.14-0.25              9          21.95
                         0.26-0.35              7          17.07
                         0.36-0.47              4          9.76
                         0.48-0.57              4          9.76
                         0.58-0.67              3          7.32
                         0.68-0.77              3          7.32
                         0.78-0.83              3          7.32
                         0.84-0.90              1          2.44
                         0.91-1.00              1          2.44

Topographic           -28.29 to -5.52           4          9.76
position index        -5.51 to -3.50            2          4.88
(TPI)                 -3.49 to -2.16            2          4.88
                      -2.15 to -1.15            1          2.44
                      -1.14 to -0.40            1          2.44
                        -0.39-0.00              1          2.44
                         0.01-1.00              5          12.20
                         1.01-3.43              6          14.63
                         3.44-7.28              11         26.83
                        7.29-30.27              8          19.51

Stream power              0-0.30                7          17.07
index (SPI)              0.31-0.64              4          9.76
                         0.65-1.08              7          17.07
                         1.09-1.59              7          17.07
                         1.60-2.34              8          19.51
                        2.35-12.74              8          19.51

Topographic              4.43-5.47              23         56.10
wetness index            5.48-5.67              9          21.95
(TWI)                    5.68-5.86              1          2.44
                         5.87-6.07              4          9.76
                         6.08-6.35              4          9.76
                         6.36-6.73              0          0.00
                         6.74-7.19              0          0.00
                         7.20-7.66              0          0.00
                       7.67-no data             0          0.00

Soil thickness              <20                 2          4.88
(unit: cm)                 20-50                6          14.63
                          50-100                25         60.98
                           >100                 8          19.51
                          No data               0          0.00

Soil material         Gneiss residuum           31         75.61
                  Granite residuum Acidic       1          2.44
                         residuum               7          17.07
                           River                2          4.88
                          No data               0          0.00

Topography           Mountainous area           8          19.51
                    Fluvial plains area         2          4.88
                        Valley area             8          19.51
                        Hilly area              23         56.10
                     Alluvial fan area          0          0.00
                    Piedmont slope area         0          0.00
                       Diluvium area            0          0.00
                          No data               0          0.00

Timber diameter         Very small              8          19.51
                           Small                12         29.27
                          Medium                19         46.34
                           Large                2          4.88
                          No data               0          0.00

Timber density             Loose                8          19.51
                         Moderate               7          17.07
                           Dense                26         63.41
                          No data               0          0.00

Lithology                   Qa                  2          4.88
                          PCEggn                0          0.00
                          PCEpgn                0          0.00
                           PCEqf                0          0.00
                          PCEbgn                39         95.12

Gradient                  0-4.52                1          2.44
                         4.53-7.26              1          2.44
                        7.27-11.30              2          4.88
                        11.31-15.79             1          2.44
                        15.80-18.44             3          7.32
                        18.45-21.80             7          17.07
                        21.81-26.33             10         24.39
                        26.34-62.53             16         39.02

Plan curvature            Concave               19         46.34
                           Flat                 7          17.07
                          Convex                15         36.59

Aspect                     Flat                 0          0.00
                             N                  4          9.76
                            NE                  3          7.32
                             E                  8          19.51
                            SE                  11         26.83
                             S                  5          12.20
                            SW                  1          2.44
                             W                  3          7.32
                            NW                  6          14.63

Midslope                  0-0.13                5          12.20
position (MSP)           0.14-0.25              10         24.39
                         0.26-0.35              6          14.63
                         0.36-0.47              6          14.63
                         0.48-0.57              4          9.76
                         0.58-0.67              4          9.76
                         0.68-0.77              2          4.88
                         0.78-0.83              4          9.76
                         0.84-0.90              0          0.00
                         0.91-1.00              0          0.00

Topographic           -28.29 to -5.52           4          9.76
position              -5.51 to -3.50            3          7.32
index (TPI)           -3.49 to -2.16            2          4.88
                      -2.15 to -1.15            1          2.44
                      -1.14 to -0.40            1          2.44
                        -0.39-0.00              1          2.44
                         0.01-1.00              3          7.32
                         1.01-3.43              8          19.51
                         3.44-7.28              9          21.95
                        7.29-30.27              9          21.95

Stream power              0-0.30                9          21.95
index (SPI)              0.31-0.64              2          4.88
                         0.65-1.08              7          17.07
                         1.09-1.59              8          19.51
                         1.60-2.34              8          19.51
                        2.35-12.74              7          17.07

Topographic              4.43-5.47              18         43.90
wetness index            5.48-5.67              13         31.71
(TWI)                    5.68-5.86              3          7.32
                         5.87-6.07              1          2.44
                         6.08-6.35              5          12.20
                         6.36-6.73              1          2.44
                         6.74-7.19              0          0.00
                         7.20-7.66              0          0.00
                       7.67-no data             0          0.00

Soil thickness              <20                 1          2.44
(unit: cm)                 20-50                8          19.51
                          50-100                23         56.10
                           >100                 9          21.95
                          No data               0          0.00

Soil material         Gneiss residuum           29         70.73
                     Granite residuum           2          4.88
                      Acidic residuum           9          21.95
                           River                1          2.44
                          No data               0          0.00

Topography           Mountainous area           13         31.71
                    Fluvial plains area         1          2.44
                        Valley area             10         24.39
                        Hilly area              16         39.02
                     Alluvial fan area          0          0.00
                    Piedmont slope area         1          2.44
                       Diluvium area            0          0.00
                          No data               0          0.00

Timber diameter         Very small              9          21.95
                           Small                11         26.83
                          Medium                20         48.78
                           Large                1          2.44
                          No data               0          0.00

Timber density             Loose                9          21.95
                         Moderate               8          19.51
                           Dense                24         58.54
                          No data               0          0.00

Lithology                   Qa                  1          2.44
                          PCEggn                0          0.00
                          PCEpgn                0          0.00
                           PCEqf                0          0.00
                          PCEbgn                40         97.56

                                            1st TD     2nd TD

Factor                     Class              FR        Number
                                                          of
                                                      landslides

Gradient                  0-4.52             0.08         0
                         4.53-7.26           0.48         2
                        7.27-11.30           0.00         1
                        11.31-15.79          0.71         2
                        15.80-18.44          0.25         3
                        18.45-21.80          1.67         7
                        21.81-26.33          2.82         8
                        26.34-62.53          3.94         18

                          Concave            2.55         22
Plan curvature             Flat              0.23         5
                          Convex             1.23         14

Aspect                     Flat              0.00         0
                             N               0.47         3
                            NE               1.37         3
                             E               2.25         6
                            SE               4.07         14
                             S               1.05         2
                            SW               0.51         1
                             W               0.53         6
                            NW               1.02         6

Midslope                  0-0.13             1.46         5
position (MSP)           0.14-0.25           2.18         8
                         0.26-0.35           1.70         7
                         0.36-0.47           0.97         4
                         0.48-0.57           0.95         4
                         0.58-0.67           0.74         4
                         0.68-0.77           0.73         4
                         0.78-0.83           0.74         3
                         0.84-0.90           0.21         1
                         0.91-1.00           0.29         1

Topographic           -28.29 to -5.52        0.98         3
position index        -5.51 to -3.50         0.49         4
(TPI)                 -3.49 to -2.16         0.49         3
                      -2.15 to -1.15         0.24         2
                      -1.14 to -0.40         0.24         1
                        -0.39-0.00           0.21         1
                         0.01-1.00           1.27         2
                         1.01-3.43           1.52         6
                         3.44-7.28           2.79         10
                        7.29-30.27           2.03         9

Stream power              0-0.30             0.34         10
index (SPI)              0.31-0.64           0.96         4
                         0.65-1.08           1.71         6
                         1.09-1.59           1.71         9
                         1.60-2.34           1.96         6
                        2.35-12.74           1.94         6

Topographic              4.43-5.47           5.51         21
wetness index            5.48-5.67           2.25         8
(TWI)                    5.68-5.86           0.24         5
                         5.87-6.07           1.00         2
                         6.08-6.35           0.98         4
                         6.36-6.73           0.00         1
                         6.74-7.19           0.00         0
                         7.20-7.66           0.00         0
                       7.67-no data          0.00         0

Soil thickness              <20              0.35         2
(unit: cm)                 20-50             1.52         7
                          50-100             1.24         23
                           >100              0.83         9
                          No data            0.00         0

Soil material         Gneiss residuum        1.35         29
                  Granite residuum Acidic    0.37         2
                         residuum            0.75         9
                           River             0.45         1
                          No data            0.00         0

Topography           Mountainous area        0.58         11
                    Fluvial plains area      0.46         1
                        Valley area          0.92         10
                        Hilly area           2.31         18
                     Alluvial fan area       0.00         0
                    Piedmont slope area      0.00         1
                       Diluvium area         0.00         0
                          No data            0.00         0

Timber diameter         Very small           10.56        9
                           Small             5.56         12
                          Medium             1.03         19
                           Large             2.79         1
                          No data            0.00         0

Timber density             Loose             9.42         9
                         Moderate            2.78         8
                           Dense             1.39         24
                          No data            0.00         0

Lithology                   Qa               0.23         1
                          PCEggn             0.00         0
                          PCEpgn             0.00         0
                           PCEqf             0.00         0
                          PCEbgn             1.47         40

Gradient                  0-4.52             0.08         1
                         4.53-7.26           0.24         0
                        7.27-11.30           0.51         1
                        11.31-15.79          0.24         2
                        15.80-18.44          0.76         1
                        18.45-21.80          1.67         6
                        21.81-26.33          2.57         10
                        26.34-62.53          3.94         20

Plan curvature            Concave            2.02         17
                           Flat              0.32         7
                          Convex             1.54         17

Aspect                     Flat              0.00         0
                             N               0.93         3
                            NE               0.82         2
                             E               2.57         7
                            SE               3.20         14
                             S               1.31         3
                            SW               0.25         4
                             W               0.80         6
                            NW               1.22         2

Midslope                  0-0.13             1.21         7
position (MSP)           0.14-0.25           2.43         11
                         0.26-0.35           1.46         5
                         0.36-0.47           1.46         3
                         0.48-0.57           0.95         5
                         0.58-0.67           0.98         6
                         0.68-0.77           0.49         1
                         0.78-0.83           0.99         2
                         0.84-0.90           0.00         0
                         0.91-1.00           0.00         1

Topographic           -28.29 to -5.52        0.98         3
position              -5.51 to -3.50         0.73         2
index (TPI)           -3.49 to -2.16         0.49         2
                      -2.15 to -1.15         0.24         1
                      -1.14 to -0.40         0.24         0
                        -0.39-0.00           0.21         0
                         0.01-1.00           0.76         5
                         1.01-3.43           2.03         9
                         3.44-7.28           2.29         10
                        7.29-30.27           2.29         9

Stream power              0-0.30             0.44         8
index (SPI)              0.31-0.64           0.48         6
                         0.65-1.08           1.71         4
                         1.09-1.59           1.96         10
                         1.60-2.34           1.96         8
                        2.35-12.74           1.70         5

Topographic              4.43-5.47           4.31         23
wetness index            5.48-5.67           3.25         10
(TWI)                    5.68-5.86           0.71         4
                         5.87-6.07           0.25         1
                         6.08-6.35           1.22         3
                         6.36-6.73           0.24         0
                         6.74-7.19           0.00         0
                         7.20-7.66           0.00         0
                       7.67-no data          0.00         0

Soil thickness              <20              0.17         1
(unit: cm)                 20-50             2.03         4
                          50-100             1.14         29
                           >100              0.93         7
                          No data            0.00         0

Soil material         Gneiss residuum        1.26         33
                     Granite residuum        0.73         3
                      Acidic residuum        0.97         5
                           River             0.23         0
                          No data            0.00         0

Topography           Mountainous area        0.94         11
                    Fluvial plains area      0.23         0
                        Valley area          1.15         8
                        Hilly area           1.61         22
                     Alluvial fan area       0.00         0
                    Piedmont slope area      0.57         0
                       Diluvium area         0.00         0
                          No data            0.00         0

Timber diameter         Very small           11.88        7
                           Small             5.10         14
                          Medium             1.09         18
                           Large             1.40         2
                          No data            0.00         0

Timber density             Loose             10.60        7
                         Moderate            3.17         11
                           Dense             1.29         23
                          No data            0.00         0

Lithology                   Qa               0.12         3
                          PCEggn             0.00         0
                          PCEpgn             0.00         0
                           PCEqf             0.00         0
                          PCEbgn             1.51         38

                                                       2nd TD

Factor                     Class               %of       FR
                                            landslide

Gradient                  0-4.52              0.00      0.00
                         4.53-7.26            4.88      0.48
                        7.27-11.30            2.44      0.25
                        11.31-15.79           4.88      0.47
                        15.80-18.44           7.32      0.76
                        18.45-21.80           17.07     1.67
                        21.81-26.33           19.51     2.05
                        26.34-62.53           43.90     4.43

                          Concave             53.66     2.34
Plan curvature             Flat               12.20     0.23
                          Convex              34.15     1.44

Aspect                     Flat               0.00      0.00
                             N                7.32      0.70
                            NE                7.32      0.82
                             E                14.63     1.93
                            SE                34.15     4.07
                             S                4.88      0.52
                            SW                2.44      0.25
                             W                14.63     1.59
                            NW                14.63     1.22

Midslope                  0-0.13              12.20     1.21
position (MSP)           0.14-0.25            19.51     1.94
                         0.26-0.35            17.07     1.70
                         0.36-0.47            9.76      0.97
                         0.48-0.57            9.76      0.95
                         0.58-0.67            9.76      0.98
                         0.68-0.77            9.76      0.98
                         0.78-0.83            7.32      0.74
                         0.84-0.90            2.44      0.21
                         0.91-1.00            2.44      0.29

Topographic           -28.29 to -5.52         7.32      0.73
position index        -5.51 to -3.50          9.76      0.98
(TPI)                 -3.49 to -2.16          7.32      0.73
                      -2.15 to -1.15          4.88      0.49
                      -1.14 to -0.40          2.44      0.24
                        -0.39-0.00            2.44      0.21
                         0.01-1.00            4.88      0.51
                         1.01-3.43            14.63     1.52
                         3.44-7.28            24.39     2.54
                        7.29-30.27            21.95     2.29

Stream power              0-0.30              24.39     0.49
index (SPI)              0.31-0.64            9.76      0.96
                         0.65-1.08            14.63     1.47
                         1.09-1.59            21.95     2.20
                         1.60-2.34            14.63     1.47
                        2.35-12.74            14.63     1.46

Topographic              4.43-5.47            51.22     5.03
wetness index            5.48-5.67            19.51     2.00
(TWI)                    5.68-5.86            12.20     1.18
                         5.87-6.07            4.88      0.50
                         6.08-6.35            9.76      0.98
                         6.36-6.73            2.44      0.24
                         6.74-7.19            0.00      0.00
                         7.20-7.66            0.00      0.00
                       7.67-no data           0.00      0.00

Soil thickness              <20               4.88      0.35
(unit: cm)                 20-50              17.07     1.78
                          50-100              56.10     1.14
                           >100               21.95     0.93
                          No data             0.00      0.00

Soil material         Gneiss residuum         70.73     1.26
                  Granite residuum Acidic     4.88      0.73
                         residuum             21.95     0.97
                           River              2.44      0.23
                          No data             0.00      0.00

Topography           Mountainous area         26.83     0.79
                    Fluvial plains area       2.44      0.23
                        Valley area           24.39     1.15
                        Hilly area            43.90     1.81
                     Alluvial fan area        0.00      0.00
                    Piedmont slope area       2.44      0.57
                       Diluvium area          0.00      0.00
                          No data             0.00      0.00

Timber diameter         Very small            21.95     11.88
                           Small              29.27     5.56
                          Medium              46.34     1.03
                           Large              2.44      1.40
                          No data             0.00      0.00

Timber density             Loose              21.95     10.60
                         Moderate             19.51     3.17
                           Dense              58.54     1.29
                          No data             0.00      0.00

Lithology                   Qa                2.44      0.12
                          PCEggn              0.00      0.00
                          PCEpgn              0.00      0.00
                           PCEqf              0.00      0.00
                          PCEbgn              97.56     1.51

Gradient                  0-4.52              2.44      0.08
                         4.53-7.26            0.00      0.00
                        7.27-11.30            2.44      0.25
                        11.31-15.79           4.88      0.47
                        15.80-18.44           2.44      0.25
                        18.45-21.80           14.63     1.43
                        21.81-26.33           24.39     2.57
                        26.34-62.53           48.78     4.93

Plan curvature            Concave             41.46     1.81
                           Flat               17.07     0.32
                          Convex              41.46     1.75

Aspect                     Flat               0.00      0.00
                             N                7.32      0.70
                            NE                4.88      0.55
                             E                17.07     2.25
                            SE                34.15     4.07
                             S                7.32      0.79
                            SW                9.76      1.01
                             W                14.63     1.59
                            NW                4.88      0.41

Midslope                  0-0.13              17.07     1.70
position (MSP)           0.14-0.25            26.83     2.67
                         0.26-0.35            12.20     1.21
                         0.36-0.47            7.32      0.73
                         0.48-0.57            12.20     1.18
                         0.58-0.67            14.63     1.47
                         0.68-0.77            2.44      0.24
                         0.78-0.83            4.88      0.49
                         0.84-0.90            0.00      0.00
                         0.91-1.00            2.44      0.29

Topographic           -28.29 to -5.52         7.32      0.73
position              -5.51 to -3.50          4.88      0.49
index (TPI)           -3.49 to -2.16          4.88      0.49
                      -2.15 to -1.15          2.44      0.24
                      -1.14 to -0.40          0.00      0.00
                        -0.39-0.00            0.00      0.00
                         0.01-1.00            12.20     1.27
                         1.01-3.43            21.95     2.29
                         3.44-7.28            24.39     2.54
                        7.29-30.27            21.95     2.29

Stream power              0-0.30              19.51     0.39
index (SPI)              0.31-0.64            14.63     1.44
                         0.65-1.08            9.76      0.98
                         1.09-1.59            24.39     2.45
                         1.60-2.34            19.51     1.96
                        2.35-12.74            12.20     1.21

Topographic              4.43-5.47            56.10     5.51
wetness index            5.48-5.67            24.39     2.50
(TWI)                    5.68-5.86            9.76      0.94
                         5.87-6.07            2.44      0.25
                         6.08-6.35            7.32      0.73
                         6.36-6.73            0.00      0.00
                         6.74-7.19            0.00      0.00
                         7.20-7.66            0.00      0.00
                       7.67-no data           0.00      0.00

Soil thickness              <20               2.44      0.17
(unit: cm)                 20-50              9.76      1.01
                          50-100              70.73     1.44
                           >100               17.07     0.73
                          No data             0.00      0.00

Soil material         Gneiss residuum         80.49     1.43
                     Granite residuum         7.32      1.10
                      Acidic residuum         12.2      0.54
                           River              0.00      0.00
                          No data             0.00      0.00

Topography           Mountainous area         26.83     0.79
                    Fluvial plains area       0.00      0.00
                        Valley area           19.51     0.92
                        Hilly area            53.66     2.21
                     Alluvial fan area        0.00      0.00
                    Piedmont slope area       0.00      0.00
                       Diluvium area          0.00      0.00
                          No data             0.00      0.00

Timber diameter         Very small            17.07     9.24
                           Small              34.15     6.49
                          Medium              43.90     0.98
                           Large              4.88      2.79
                          No data             0.00      0.00

Timber density             Loose              17.07     8.24
                         Moderate             26.83     4.36
                           Dense              56.10     1.23
                          No data             0.00      0.00

Lithology                   Qa                7.32      0.35
                          PCEggn              0.00      0.00
                          PCEpgn              0.00      0.00
                           PCEqf              0.00      0.00
                          PCEbgn              92.68     1.43

                                                    3rd TD

Factor                     Class              Number        %of
                                                of       landslide
                                            landslides

Gradient                  0-4.52                0          0.00
                         4.53-7.26              2          4.88
                        7.27-11.30              2          4.88
                        11.31-15.79             2          4.88
                        15.80-18.44             3          7.32
                        18.45-21.80             8          19.51
                        21.81-26.33             7          17.07
                        26.34-62.53             17         41.46

                          Concave               20         48.78
Plan curvature             Flat                 11         26.83
                          Convex                10         24.39

Aspect                     Flat                 0          0.00
                             N                  4          9.76
                            NE                  4          9.76
                             E                  9          21.95
                            SE                  10         24.39
                             S                  3          7.32
                            SW                  3          7.32
                             W                  3          7.32
                            NW                  5          12.20

Midslope                  0-0.13                7          17.07
position (MSP)           0.14-0.25              8          19.51
                         0.26-0.35              6          14.63
                         0.36-0.47              5          12.20
                         0.48-0.57              3          7.32
                         0.58-0.67              3          7.32
                         0.68-0.77              3          7.32
                         0.78-0.83              5          12.20
                         0.84-0.90              1          2.44
                         0.91-1.00              0          0.00

Topographic           -28.29 to -5.52           4          9.76
position index        -5.51 to -3.50            4          9.76
(TPI)                 -3.49 to -2.16            1          2.44
                      -2.15 to -1.15            2          4.88
                      -1.14 to -0.40            0          0.00
                        -0.39-0.00              1          2.44
                         0.01-1.00              5          12.20
                         1.01-3.43              5          12.20
                         3.44-7.28              11         26.83
                        7.29-30.27              8          19.51

Stream power              0-0.30                7          17.07
index (SPI)              0.31-0.64              5          12.20
                         0.65-1.08              9          21.95
                         1.09-1.59              5          12.20
                         1.60-2.34              5          12.20
                        2.35-12.74              10         24.39

Topographic              4.43-5.47              23         56.10
wetness index            5.48-5.67              8          19.51
(TWI)                    5.68-5.86              1          2.44
                         5.87-6.07              2          4.88
                         6.08-6.35              6          14.63
                         6.36-6.73              1          2.44
                         6.74-7.19              0          0.00
                         7.20-7.66              0          0.00
                       7.67-no data             0          0.00

Soil thickness              <20                 3          7.32
(unit: cm)                 20-50                6          14.63
                          50-100                25         60.98
                           >100                 7          17.07
                          No data               0          0.00

Soil material         Gneiss residuum           31         75.61
                  Granite residuum Acidic       2          4.88
                         residuum               6          14.63
                           River                2          4.88
                          No data               0          0.00

Topography           Mountainous area           10         24.39
                    Fluvial plains area         2          4.88
                        Valley area             7          17.07
                        Hilly area              21         51.22
                     Alluvial fan area          0          0.00
                    Piedmont slope area         1          2.44
                       Diluvium area            0          0.00
                          No data               0          0.00

Timber diameter         Very small              8          19.51
                           Small                10         24.39
                          Medium                23         56.10
                           Large                0          0.00
                          No data               0          0.00

Timber density             Loose                8          19.51
                         Moderate               8          19.51
                           Dense                25         60.98
                          No data               0          0.00

Lithology                   Qa                  1          2.44
                          PCEggn                0          0.00
                          PCEpgn                0          0.00
                           PCEqf                0          0.00
                          PCEbgn                40         97.56

Gradient                  0-4.52                1          2.44
                         4.53-7.26              1          2.44
                        7.27-11.30              2          4.88
                        11.31-15.79             2          4.88
                        15.80-18.44             3          7.32
                        18.45-21.80             6          14.63
                        21.81-26.33             9          21.95
                        26.34-62.53             17         41.46

Plan curvature            Concave               15         36.59
                           Flat                 9          21.95
                          Convex                17         41.46

Aspect                     Flat                 0          0.00
                             N                  4          9.76
                            NE                  5          12.20
                             E                  4          9.76
                            SE                  13         31.71
                             S                  4          9.76
                            SW                  5          12.20
                             W                  3          7.32
                            NW                  3          7.32

Midslope                  0-0.13                5          12.20
position (MSP)           0.14-0.25              11         26.83
                         0.26-0.35              7          17.07
                         0.36-0.47              6          14.63
                         0.48-0.57              4          9.76
                         0.58-0.67              2          4.88
                         0.68-0.77              2          4.88
                         0.78-0.83              2          4.88
                         0.84-0.90              1          2.44
                         0.91-1.00              1          2.44

Topographic           -28.29 to -5.52           3          7.32
position              -5.51 to -3.50            3          7.32
index (TPI)           -3.49 to -2.16            2          4.88
                      -2.15 to -1.15            1          2.44
                      -1.14 to -0.40            2          4.88
                        -0.39-0.00              0          0.00
                         0.01-1.00              4          9.76
                         1.01-3.43              8          19.51
                         3.44-7.28              11         26.83
                        7.29-30.27              7          17.07

Stream power              0-0.30                8          19.51
index (SPI)              0.31-0.64              5          12.20
                         0.65-1.08              6          14.63
                         1.09-1.59              12         29.27
                         1.60-2.34              6          14.63
                        2.35-12.74              4          9.76

Topographic              4.43-5.47              19         46.34
wetness index            5.48-5.67              11         26.83
(TWI)                    5.68-5.86              2          4.88
                         5.87-6.07              4          9.76
                         6.08-6.35              4          9.76
                         6.36-6.73              1          2.44
                         6.74-7.19              0          0.00
                         7.20-7.66              0          0.00
                       7.67-no data             0          0.00

Soil thickness              <20                 2          4.88
(unit: cm)                 20-50                7          17.07
                          50-100                24         58.54
                           >100                 8          19.51
                          No data               0          0.00

Soil material         Gneiss residuum           29         70.73
                     Granite residuum           3          7.32
                      Acidic residuum           8          19.51
                           River                1          2.44
                          No data               0          0.00

Topography           Mountainous area           12         29.27
                    Fluvial plains area         1          2.44
                        Valley area             10         24.39
                        Hilly area              17         41.46
                     Alluvial fan area          0          0.00
                    Piedmont slope area         1          2.44
                       Diluvium area            0          0.00
                          No data               0          0.00

Timber diameter         Very small              11         26.83
                           Small                11         26.83
                          Medium                17         41.46
                           Large                2          4.88
                          No data               0          0.00

Timber density             Loose                11         26.83
                         Moderate               7          17.07
                           Dense                23         56.10
                          No data               0          0.00

Lithology                   Qa                  3          7.32
                          PCEggn                0          0.00
                          PCEpgn                0          0.00
                           PCEqf                0          0.00
                          PCEbgn                38         92.68

                                            3rd TD    4th TD

Factor                     Class              FR       Number
                                                         of
                                                     landslides

Gradient                  0-4.52             0.00        1
                         4.53-7.26           0.48        1
                        7.27-11.30           0.51        0
                        11.31-15.79          0.47        3
                        15.80-18.44          0.76        1
                        18.45-21.80          1.91        6
                        21.81-26.33          1.80        9
                        26.34-62.53          4.19        20

                          Concave            2.12        23
Plan curvature             Flat              0.50        6
                          Convex             1.03        12

Aspect                     Flat              0.00        0
                             N               0.93        3
                            NE               1.09        5
                             E               2.89        5
                            SE               2.91        14
                             S               0.79        4
                            SW               0.76        2
                             W               0.80        3
                            NW               1.02        5

Midslope                  0-0.13             1.70        4
position (MSP)           0.14-0.25           1.94        10
                         0.26-0.35           1.46        9
                         0.36-0.47           1.22        5
                         0.48-0.57           0.71        2
                         0.58-0.67           0.74        3
                         0.68-0.77           0.73        5
                         0.78-0.83           1.23        1
                         0.84-0.90           0.21        1
                         0.91-1.00           0.00        1

Topographic           -28.29 to -5.52        0.98        3
position index        -5.51 to -3.50         0.98        2
(TPI)                 -3.49 to -2.16         0.24        4
                      -2.15 to -1.15         0.49        2
                      -1.14 to -0.40         0.00        1
                        -0.39-0.00           0.21        0
                         0.01-1.00           1.27        3
                         1.01-3.43           1.27        7
                         3.44-7.28           2.79        12
                        7.29-30.27           2.03        7

Stream power              0-0.30             0.34        6
index (SPI)              0.31-0.64           1.20        6
                         0.65-1.08           2.20        6
                         1.09-1.59           1.22        10
                         1.60-2.34           1.22        6
                        2.35-12.74           2.43        7

Topographic              4.43-5.47           5.51        22
wetness index            5.48-5.67           2.00        12
(TWI)                    5.68-5.86           0.24        1
                         5.87-6.07           0.50        1
                         6.08-6.35           1.47        5
                         6.36-6.73           0.24        0
                         6.74-7.19           0.00        0
                         7.20-7.66           0.00        0
                       7.67-no data          0.00        0

Soil thickness              <20              0.52        2
(unit: cm)                 20-50             1.52        5
                          50-100             1.24        25
                           >100              0.73        9
                          No data            0.00        0

Soil material         Gneiss residuum        1.35        29
                  Granite residuum Acidic    0.73        2
                         residuum            0.65        9
                           River             0.45        1
                          No data            0.00        0

Topography           Mountainous area        0.72        8
                    Fluvial plains area      0.46        1
                        Valley area          0.81        11
                        Hilly area           2.11        21
                     Alluvial fan area       0.00        0
                    Piedmont slope area      0.57        0
                       Diluvium area         0.00        0
                          No data            0.00        0

Timber diameter         Very small          10.56        9
                           Small             4.64        12
                          Medium             1.25        19
                           Large             0.00        1
                          No data            0.00        0

Timber density             Loose             9.42        11
                         Moderate            3.17        9
                           Dense             1.34        23
                          No data            0.00        0

Lithology                   Qa               0.12        2
                          PCEggn             0.00        0
                          PCEpgn             0.00        0
                           PCEqf             0.00        0
                          PCEbgn             1.51        39

Gradient                  0-4.52             0.08        1
                         4.53-7.26           0.24        0
                        7.27-11.30           0.51        0
                        11.31-15.79          0.47        3
                        15.80-18.44          0.76        4
                        18.45-21.80          1.43        6
                        21.81-26.33          2.31        12
                        26.34-62.53          4.19        15

Plan curvature            Concave            1.59        23
                           Flat              0.41        7
                          Convex             1.75        11

Aspect                     Flat              0.00        0
                             N               0.93        4
                            NE               1.37        3
                             E               1.28        8
                            SE               3.78        13
                             S               1.05        3
                            SW               1.27        3
                             W               0.80        3
                            NW               0.61        4

Midslope                  0-0.13             1.21        8
position (MSP)           0.14-0.25           2.67        7
                         0.26-0.35           1.70        8
                         0.36-0.47           1.46        5
                         0.48-0.57           0.95        3
                         0.58-0.67           0.49        5
                         0.68-0.77           0.49        2
                         0.78-0.83           0.49        3
                         0.84-0.90           0.21        0
                         0.91-1.00           0.29        0

Topographic           -28.29 to -5.52        0.73        3
position              -5.51 to -3.50         0.73        2
index (TPI)           -3.49 to -2.16         0.49        2
                      -2.15 to -1.15         0.24        1
                      -1.14 to -0.40         0.49        1
                        -0.39-0.00           0.00        1
                         0.01-1.00           1.02        2
                         1.01-3.43           2.03        8
                         3.44-7.28           2.79        12
                        7.29-30.27           1.78        9

Stream power              0-0.30             0.39        10
index (SPI)              0.31-0.64           1.20        5
                         0.65-1.08           1.47        4
                         1.09-1.59           2.94        8
                         1.60-2.34           1.47        9
                        2.35-12.74           0.97        5

Topographic              4.43-5.47           4.55        21
wetness index            5.48-5.67           2.75        7
(TWI)                    5.68-5.86           0.47        4
                         5.87-6.07           1.00        5
                         6.08-6.35           0.98        4
                         6.36-6.73           0.24        0
                         6.74-7.19           0.00        0
                         7.20-7.66           0.00        0
                       7.67-no data          0.00        0

Soil thickness              <20              0.35        0
(unit: cm)                 20-50             1.78        5
                          50-100             1.19        30
                           >100              0.83        6
                          No data            0.00        0

Soil material         Gneiss residuum        1.26        32
                     Granite residuum        1.10        2
                      Acidic residuum        0.86        6
                           River             0.23        1
                          No data            0.00        0

Topography           Mountainous area        0.86        11
                    Fluvial plains area      0.23        1
                        Valley area          1.15        8
                        Hilly area           1.71        21
                     Alluvial fan area       0.00        0
                    Piedmont slope area      0.57        0
                       Diluvium area         0.00        0
                          No data            0.00        0

Timber diameter         Very small          14.52        8
                           Small             5.10        12
                          Medium             0.92        20
                           Large             2.79        1
                          No data            0.00        0

Timber density             Loose            12.96        8
                         Moderate            2.78        7
                           Dense             0.00        26
                          No data            1.23        0

Lithology                   Qa               0.35        0
                          PCEggn             0.00        0
                          PCEpgn             0.00        0
                           PCEqf             0.00        0
                          PCEbgn             1.43        41

                                                   4th TD

Factor                     Class               %of       FR
                                            landslide

Gradient                  0-4.52              2.44      0.08
                         4.53-7.26            2.44      0.24
                        7.27-11.30            0.00      0.00
                        11.31-15.79           7.32      0.71
                        15.80-18.44           2.44      0.25
                        18.45-21.80           14.63     1.43
                        21.81-26.33           21.95     2.31
                        26.34-62.53           48.78     4.93

                          Concave             56.10     2.44
Plan curvature             Flat               14.63     0.27
                          Convex              29.27     1.23

Aspect                     Flat               0.00      0.00
                             N                7.32      0.70
                            NE                12.20     1.37
                             E                12.20     1.61
                            SE                34.15     4.07
                             S                9.76      1.05
                            SW                4.88      0.51
                             W                7.32      0.80
                            NW                12.20     1.02

Midslope                  0-0.13              9.76      0.97
position (MSP)           0.14-0.25            24.39     2.43
                         0.26-0.35            21.95     2.18
                         0.36-0.47            12.20     1.22
                         0.48-0.57            4.88      0.47
                         0.58-0.67            7.32      0.74
                         0.68-0.77            12.20     1.22
                         0.78-0.83            2.44      0.25
                         0.84-0.90            2.44      0.21
                         0.91-1.00            2.44      0.29

Topographic           -28.29 to -5.52         7.32      0.73
position index        -5.51 to -3.50          4.88      0.49
(TPI)                 -3.49 to -2.16          9.76      0.98
                      -2.15 to -1.15          4.88      0.49
                      -1.14 to -0.40          2.44      0.24
                        -0.39-0.00            0.00      0.00
                         0.01-1.00            7.32      0.76
                         1.01-3.43            17.07     1.78
                         3.44-7.28            29.27     3.05
                        7.29-30.27            17.07     1.78

Stream power              0-0.30              14.63     0.29
index (SPI)              0.31-0.64            14.63     1.44
                         0.65-1.08            14.63     1.47
                         1.09-1.59            24.39     2.45
                         1.60-2.34            14.63     1.47
                        2.35-12.74            17.07     1.70

Topographic              4.43-5.47            53.66     5.27
wetness index            5.48-5.67            29.27     3.00
(TWI)                    5.68-5.86            2.44      0.24
                         5.87-6.07            2.44      0.25
                         6.08-6.35            12.20     1.22
                         6.36-6.73            0.00      0.00
                         6.74-7.19            0.00      0.00
                         7.20-7.66            0.00      0.00
                       7.67-no data           0.00      0.00

Soil thickness              <20               4.88      0.35
(unit: cm)                 20-50              12.20     1.27
                          50-100              60.98     1.24
                           >100               21.95     0.93
                          No data             0.00      0.00

Soil material         Gneiss residuum         70.73     1.26
                  Granite residuum Acidic     4.88      0.73
                         residuum             21.95     0.97
                           River              2.44      0.23
                          No data             0.00      0.00

Topography           Mountainous area         19.51     0.58
                    Fluvial plains area       2.44      0.23
                        Valley area           26.83     1.27
                        Hilly area            51.22     2.11
                     Alluvial fan area        0.00      0.00
                    Piedmont slope area       0.00      0.00
                       Diluvium area          0.00      0.00
                          No data             0.00      0.00

Timber diameter         Very small            21.95     11.88
                           Small              29.27     5.56
                          Medium              46.34     1.03
                           Large              2.44      1.40
                          No data             0.00      0.00

Timber density             Loose              26.83     12.96
                         Moderate             21.95     3.57
                           Dense              56.10     1.23
                          No data             0.00      0.00

Lithology                   Qa                4.88      0.23
                          PCEggn              0.00      0.00
                          PCEpgn              0.00      0.00
                           PCEqf              0.00      0.00
                          PCEbgn              95.12     1.47

Gradient                  0-4.52              2.44      0.08
                         4.53-7.26            0.00      0.00
                        7.27-11.30            0.00      0.00
                        11.31-15.79           7.32      0.71
                        15.80-18.44           9.76      1.01
                        18.45-21.80           14.63     1.43
                        21.81-26.33           29.27     3.08
                        26.34-62.53           36.59     3.70

Plan curvature            Concave             56.10     2.44
                           Flat               17.07     0.32
                          Convex              26.83     1.13

Aspect                     Flat               0.00      0.00
                             N                9.76      0.93
                            NE                7.32      0.82
                             E                19.51     2.57
                            SE                31.71     3.78
                             S                7.32      0.79
                            SW                7.32      0.76
                             W                7.32      0.80
                            NW                9.76      0.81

Midslope                  0-0.13              19.51     1.94
position (MSP)           0.14-0.25            17.07     1.70
                         0.26-0.35            19.51     1.94
                         0.36-0.47            12.20     1.22
                         0.48-0.57            7.32      0.71
                         0.58-0.67            12.20     1.23
                         0.68-0.77            4.88      0.49
                         0.78-0.83            7.32      0.74
                         0.84-0.90            0.00      0.00
                         0.91-1.00            0.00      0.00

Topographic           -28.29 to -5.52         7.32      0.73
position              -5.51 to -3.50          4.88      0.49
index (TPI)           -3.49 to -2.16          4.88      0.49
                      -2.15 to -1.15          2.44      0.24
                      -1.14 to -0.40          2.44      0.24
                        -0.39-0.00            2.44      0.21
                         0.01-1.00            4.88      0.51
                         1.01-3.43            19.51     2.03
                         3.44-7.28            29.27     3.05
                        7.29-30.27            21.95     2.29

Stream power              0-0.30              24.39     0.49
index (SPI)              0.31-0.64            12.20     1.20
                         0.65-1.08            9.76      0.98
                         1.09-1.59            19.51     1.96
                         1.60-2.34            21.95     2.20
                        2.35-12.74            12.20     1.21

Topographic              4.43-5.47            51.22     5.03
wetness index            5.48-5.67            17.07     1.75
(TWI)                    5.68-5.86            9.76      0.94
                         5.87-6.07            12.20     1.25
                         6.08-6.35            9.76      0.98
                         6.36-6.73            0.00      0.00
                         6.74-7.19            0.00      0.00
                         7.20-7.66            0.00      0.00
                       7.67-no data           0.00      0.00

Soil thickness              <20               0.00      0.00
(unit: cm)                 20-50              12.20     1.27
                          50-100              73.17     1.49
                           >100               14.63     0.62
                          No data             0.00      0.00

Soil material         Gneiss residuum         78.05     1.39
                     Granite residuum         4.88      0.73
                      Acidic residuum         14.63     0.65
                           River              2.44      0.23
                          No data             0.00      0.00

Topography           Mountainous area         26.83     0.79
                    Fluvial plains area       2.44      0.23
                        Valley area           19.51     0.92
                        Hilly area            51.22     2.11
                     Alluvial fan area        0.00      0.00
                    Piedmont slope area       0.00      0.00
                       Diluvium area          0.00      0.00
                          No data             0.00      0.00

Timber diameter         Very small            19.51     10.56
                           Small              29.27     5.56
                          Medium              48.78     1.09
                           Large              2.44      1.40
                          No data             0.00      0.00

Timber density             Loose              19.51     9.42
                         Moderate             17.07     2.78
                           Dense              63.41     1.39
                          No data             0.00      0.00

Lithology                   Qa                0.00      0.00
                          PCEggn              0.00      0.00
                          PCEpgn              0.00      0.00
                           PCEqf              0.00      0.00
                          PCEbgn             100.00     1.54

                                                      5th TD

Factor                     Class              Number        %of
                                                of       landslide
                                            landslides

Gradient                  0-4.52                1          2.44
                         4.53-7.26              2          4.88
                        7.27-11.30              1          2.44
                        11.31-15.79             2          4.88
                        15.80-18.44             2          4.88
                        18.45-21.80             7          17.07
                        21.81-26.33             9          21.95
                        26.34-62.53             17         41.46

                          Concave               23         56.10
Plan curvature             Flat                 10         24.39
                          Convex                8          19.51

Aspect                     Flat                 0          0.00
                             N                  2          4.88
                            NE                  4          9.76
                             E                  5          12.20
                            SE                  16         39.02
                             S                  4          9.76
                            SW                  1          2.44
                             W                  3          7.32
                            NW                  6          14.63

Midslope                  0-0.13                6          14.63
position (MSP)           0.14-0.25              10         24.39
                         0.26-0.35              6          14.63
                         0.36-0.47              3          7.32
                         0.48-0.57              3          7.32
                         0.58-0.67              3          7.32
                         0.68-0.77              4          9.76
                         0.78-0.83              5          12.20
                         0.84-0.90              1          2.44
                         0.91-1.00              0          0.00

Topographic           -28.29 to -5.52           4          9.76
position index        -5.51 to -3.50            4          9.76
(TPI)                 -3.49 to -2.16            1          2.44
                      -2.15 to -1.15            2          4.88
                      -1.14 to -0.40            0          0.00
                        -0.39-0.00              1          2.44
                         0.01-1.00              3          7.32
                         1.01-3.43              8          19.51
                         3.44-7.28              10         24.39
                        7.29-30.27              8          19.51

Stream power              0-0.30                7          17.07
index (SPI)              0.31-0.64              5          12.20
                         0.65-1.08              5          12.20
                         1.09-1.59              7          17.07
                         1.60-2.34              8          19.51
                        2.35-12.74              9          21.95

Topographic              4.43-5.47              18         43.90
wetness index            5.48-5.67              11         26.83
(TWI)                    5.68-5.86              2          4.88
                         5.87-6.07              3          7.32
                         6.08-6.35              6          14.63
                         6.36-6.73              1          2.44
                         6.74-7.19              0          0.00
                         7.20-7.66              0          0.00
                       7.67-no data             0          0.00

Soil thickness              <20                 2          4.88
(unit: cm)                 20-50                8          19.51
                          50-100                24         58.54
                           >100                 7          17.07
                          No data               0          0.00

Soil material         Gneiss residuum           31         75.61
                  Granite residuum Acidic       2          4.88
                         residuum               7          17.07
                           River                1          2.44
                          No data               0          0.00

Topography           Mountainous area           12         29.27
                    Fluvial plains area         1          2.44
                        Valley area             8          19.51
                        Hilly area              19         46.34
                     Alluvial fan area          0          0.00
                    Piedmont slope area         1          2.44
                       Diluvium area            0          0.00
                          No data               0          0.00

Timber diameter         Very small              9          21.95
                           Small                13         31.71
                          Medium                18         43.90
                           Large                1          2.44
                          No data               0          0.00

Timber density             Loose                9          21.95
                         Moderate               7          17.07
                           Dense                25         60.98
                          No data               0          0.00

Lithology                   Qa                  1          2.44
                          PCEggn                0          0.00
                          PCEpgn                0          0.00
                           PCEqf                0          0.00
                          PCEbgn                40         97.56

Gradient                  0-4.52                1          2.44
                         4.53-7.26              2          4.88
                        7.27-11.30              2          4.88
                        11.31-15.79             1          2.44
                        15.80-18.44             2          4.88
                        18.45-21.80             9          21.95
                        21.81-26.33             9          21.95
                        26.34-62.53             15         36.59

Plan curvature            Concave               19         46.34
                           Flat                 11         26.83
                          Convex                11         26.83

Aspect                     Flat                 0          0.00
                             N                  5          12.20
                            NE                  3          7.32
                             E                  5          12.20
                            SE                  12         29.27
                             S                  3          7.32
                            SW                  3          7.32
                             W                  4          9.76
                            NW                  6          14.63

Midslope                  0-0.13                3          7.32
position (MSP)           0.14-0.25              10         24.39
                         0.26-0.35              5          12.20
                         0.36-0.47              6          14.63
                         0.48-0.57              3          7.32
                         0.58-0.67              5          12.20
                         0.68-0.77              3          7.32
                         0.78-0.83              4          9.76
                         0.84-0.90              1          2.44
                         0.91-1.00              1          2.44

Topographic           -28.29 to -5.52           4          9.76
position              -5.51 to -3.50            3          7.32
index (TPI)           -3.49 to -2.16            2          4.88
                      -2.15 to -1.15            1          2.44
                      -1.14 to -0.40            1          2.44
                        -0.39-0.00              0          0.00
                         0.01-1.00              3          7.32
                         1.01-3.43              10         24.39
                         3.44-7.28              10         24.39
                        7.29-30.27              7          17.07

Stream power              0-0.30                8          19.51
index (SPI)              0.31-0.64              4          9.76
                         0.65-1.08              9          21.95
                         1.09-1.59              9          21.95
                         1.60-2.34              7          17.07
                        2.35-12.74              4          9.76

Topographic              4.43-5.47              20         48.78
wetness index            5.48-5.67              9          21.95
(TWI)                    5.68-5.86              3          7.32
                         5.87-6.07              3          7.32
                         6.08-6.35              5          12.20
                         6.36-6.73              1          2.44
                         6.74-7.19              0          0.00
                         7.20-7.66              0          0.00
                       7.67-no data             0          0.00

Soil thickness              <20                 1          2.44
(unit: cm)                 20-50                7          17.07
                          50-100                26         63.41
                           >100                 7          17.07
                          No data               0          0.00

Soil material         Gneiss residuum           31         75.61
                     Granite residuum           1          2.44
                      Acidic residuum           9          21.95
                           River                0          0.00.
                          No data               0          0.00

Topography           Mountainous area           11         26.83
                    Fluvial plains area         0          0.00
                        Valley area             9          21.95
                        Hilly area              20         48.78
                     Alluvial fan area          0          0.00
                    Piedmont slope area         1          2.44
                       Diluvium area            0          0.00
                          No data               0          0.00

Timber diameter         Very small              9          21.95
                           Small                13         31.71
                          Medium                18         43.90
                           Large                1          2.44
                          No data               0          0.00

Timber density             Loose                9          21.95
                         Moderate               12         29.27
                           Dense                20         48.78
                          No data               0          0.00

Lithology                   Qa                  0          0.00
                          PCEggn                0          0.00
                          PCEpgn                0          0.00
                           PCEqf                0          0.00
                          PCEbgn                41        100.00

                                            5th TD

Factor                     Class              FR

Gradient                  0-4.52             0.08
                         4.53-7.26           0.48
                        7.27-11.30           0.25
                        11.31-15.79          0.47
                        15.80-18.44          0.51
                        18.45-21.80          1.67
                        21.81-26.33          2.31
                        26.34-62.53          4.19

                          Concave            2.44
Plan curvature             Flat              0.46
                          Convex             0.82

Aspect                     Flat              0.00
                             N               0.47
                            NE               1.09
                             E               1.61
                            SE               4.65
                             S               1.05
                            SW               0.25
                             W               0.80
                            NW               1.22

Midslope                  0-0.13             1.46
position (MSP)           0.14-0.25           2.43
                         0.26-0.35           1.46
                         0.36-0.47           0.73
                         0.48-0.57           0.71
                         0.58-0.67           0.74
                         0.68-0.77           0.98
                         0.78-0.83           1.23
                         0.84-0.90           0.21
                         0.91-1.00           0.00

Topographic           -28.29 to -5.52        0.98
position index        -5.51 to -3.50         0.98
(TPI)                 -3.49 to -2.16         0.24
                      -2.15 to -1.15         0.49
                      -1.14 to -0.40         0.00
                        -0.39-0.00           0.21
                         0.01-1.00           0.76
                         1.01-3.43           2.03
                         3.44-7.28           2.54
                        7.29-30.27           2.03

Stream power              0-0.30             0.34
index (SPI)              0.31-0.64           1.20
                         0.65-1.08           1.22
                         1.09-1.59           1.71
                         1.60-2.34           1.96
                        2.35-12.74           2.19

Topographic              4.43-5.47           4.31
wetness index            5.48-5.67           2.75
(TWI)                    5.68-5.86           0.47
                         5.87-6.07           0.75
                         6.08-6.35           1.47
                         6.36-6.73           0.24
                         6.74-7.19           0.00
                         7.20-7.66           0.00
                       7.67-no data          0.00

Soil thickness              <20              0.35
(unit: cm)                 20-50             2.03
                          50-100             1.19
                           >100              0.73
                          No data            0.00

Soil material         Gneiss residuum        1.35
                  Granite residuum Acidic    0.73
                         residuum            0.75
                           River             0.23
                          No data            0.00

Topography           Mountainous area        0.86
                    Fluvial plains area      0.23
                        Valley area          0.92
                        Hilly area           1.91
                     Alluvial fan area       0.00
                    Piedmont slope area      0.57
                       Diluvium area         0.00
                          No data            0.00

Timber diameter         Very small           11.88
                           Small             6.03
                          Medium             0.98
                           Large             1.40
                          No data            0.00

Timber density             Loose             10.60
                         Moderate            2.78
                           Dense             1.34
                          No data            0.00

Lithology                   Qa               0.12
                          PCEggn             0.00
                          PCEpgn             0.00
                           PCEqf             0.00
                          PCEbgn             1.51

Gradient                  0-4.52             0.08
                         4.53-7.26           0.48
                        7.27-11.30           0.51
                        11.31-15.79          0.24
                        15.80-18.44          0.51
                        18.45-21.80          2.14
                        21.81-26.33          2.31
                        26.34-62.53          3.70

Plan curvature            Concave            2.02
                           Flat              0.50
                          Convex             1.13

Aspect                     Flat              0.00
                             N               1.17
                            NE               0.82
                             E               1.61
                            SE               3.49
                             S               0.79
                            SW               0.76
                             W               1.06
                            NW               1.22

Midslope                  0-0.13             0.73
position (MSP)           0.14-0.25           2.43
                         0.26-0.35           1.21
                         0.36-0.47           1.46
                         0.48-0.57           0.71
                         0.58-0.67           1.23
                         0.68-0.77           0.73
                         0.78-0.83           0.99
                         0.84-0.90           0.21
                         0.91-1.00           0.29

Topographic           -28.29 to -5.52        0.98
position              -5.51 to -3.50         0.73
index (TPI)           -3.49 to -2.16         0.49
                      -2.15 to -1.15         0.24
                      -1.14 to -0.40         0.24
                        -0.39-0.00           0.00
                         0.01-1.00           0.76
                         1.01-3.43           2.54
                         3.44-7.28           2.54
                        7.29-30.27           1.78

Stream power              0-0.30             0.39
index (SPI)              0.31-0.64           0.96
                         0.65-1.08           2.20
                         1.09-1.59           2.20
                         1.60-2.34           1.71
                        2.35-12.74           0.97

Topographic              4.43-5.47           4.79
wetness index            5.48-5.67           2.25
(TWI)                    5.68-5.86           0.71
                         5.87-6.07           0.75
                         6.08-6.35           1.22
                         6.36-6.73           0.24
                         6.74-7.19           0.00
                         7.20-7.66           0.00
                       7.67-no data          0.00

Soil thickness              <20              0.17
(unit: cm)                 20-50             1.78
                          50-100             1.29
                           >100              0.73
                          No data            0.00

Soil material         Gneiss residuum        1.35
                     Granite residuum        0.37
                      Acidic residuum        0.97
                           River             0.00
                          No data            0.00

Topography           Mountainous area        0.79
                    Fluvial plains area      0.00
                        Valley area          1.04
                        Hilly area           2.01
                     Alluvial fan area       0.00
                    Piedmont slope area      0.57
                       Diluvium area         0.00
                          No data            0.00

Timber diameter         Very small           11.88
                           Small             6.03
                          Medium             0.98
                           Large             1.40
                          No data            0.00

Timber density             Loose             10.60
                         Moderate            4.76
                           Dense             1.07
                          No data            0.00

Lithology                   Qa               0.00
                          PCEggn             0.00
                          PCEpgn             0.00
                           PCEqf             0.00
                          PCEbgn             1.54

Number of training data: 41 landslide occurrences. Abbreviations of
Lithohgy. Qa: Alluvium; PCEggn: Granite Gneiss; PCEpgn:
Porphyroblastic Gneiss; PCEqf: Quartzofeldspathic Gneiss; PCEbgn:
Biotite Gneiss.
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Title Annotation:Research Article
Author:Oh, Hyun-Joo; Lee, Saro; Hong, Soo-Min
Publication:Journal of Sensors
Date:Jan 1, 2017
Words:18950
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