The distribution and morphometry of lakes and reservoirs in British Columbia: a provincial inventory.
Lakes play an important role as a critical ecosystem component for many aquatic and terrestrial plant and animal species and are an invaluable freshwater resource for human populations. To improve the regional knowledge base of British Columbia's water resources, a comprehensive inventory and assessment of the distribution and morphometry of lakes and reservoirs has been developed using the most recently available provincial mapping and the large-scale spatial-analysis capabilities of Geographic Information Systems (GIS). The abundance of lake bodies and their extensive distribution across the physiographically diverse and largely remote landmass of British Columbia have hindered previous attempts to carry out such an analysis (Northcote and Larkin 1956; Northcote 1964; Trainor and Church 1996). Furthermore, there exists a continuum of lakes and other surface-water features, including ponds (scale continuum), wetlands (maturity continuum) and rivers (flow dynamics continuum), that makes classification difficult. Although British Columbia has fewer lakes than the other western Canadian provinces (Northcote and Larkin 1963), it probably contains the greatest diversity of lake types because of the complex tectonic and glacial history of the Canadian cordillera. The largest water bodies and major physiographic elements of the province (based on Mathews 1986) are shown in Figure 1.
[FIGURE 1 OMITTED]
From a regional perspective, a provincial lake inventory would enhance our potential understanding of the physical, chemical and biological nature of the lakes of British Columbia. Such an inventory and classification of our physical landscape features will be necessary for the management and protection of provincial freshwater resources and aquatic ecosystems. The inventory may also be useful in characterising regional geomorphology and hydrology of the province and will serve as an example of how large digital databases and GIS capabilities may be utilised in cataloguing and interpreting landscapes in a spatial context.
Northcote and Larkin (1956) used lake surveys compiled by the British Columbia Game Commission (100 lakes) to investigate relations between the physical and chemical characteristics of the lakes and standing crops of organisms. Total dissolved content of lake water was concluded to be the most important factor in determining standing crops in lakes of British Columbia. Based primarily on productivity, nine limnologic regions were proposed for the province. Northcote (1964) provided additional information on these regions, briefly described several new regions and made the first attempt to enumerate the number of lakes in British Columbia for the purpose of sport-fish management. Using the limited government resource mapping available at that time, it was estimated that there were over 20,000 lakes in the province. Northcote and Larkin (1963) provide a review of early limnologic endeavours and limnologic research carried out in British Columbia.
Based on eighty years of lake surveying, the Ministry of Sustainable Resource Management (2003), Aquatic Information Branch, has compiled and curates a provincial fisheries lake survey that contains basic morphometric data (including lake volume) for approximately 3,000 lakes. Using a subset of this inventory in conjunction with the Lake Classification Project Database (collected by the Canada Department of Fisberies and Oceans--1,000 lakes in total), Trainor and Church (1996) carried out a morphometric assessment and characterisation for three provincial subregions. Principal findings of the study included the identification of a clear planimetric relation between lake perimeter and area and a regionally variable hypsometric relation between lake volume and depth versus area. All relations exhibited substantial residual scatter. Variates of ecological interest, including lake littoral area and flushing time, were also investigated.
The largest lake database for British Columbia is contained within the Terrain Resource Inventory Management (TRIM) program 1:20,000 baseline provincial mapping. This digital database contains planimetric information on over 300,000 lakes. As yet, no province-wide assessment of lake distribution or morphometry has been carried out using this inventory.
Polygons representing definite lakes (feature code: GB15300000; definition: A body of fresh water that is completely surrounded by land) and islands (feature code: GE14850000; definition: A land mass completely surrounded by water) were extracted from the 1:20,000 TRIM database for the entire province (7,027 map files in total). These features represent the interpreted high water mark and include all lake bodies that have a length dimension over 25 m (Geographic Data BC 1992). All lake and island features were appended, and common borders were dissolved. Lake features with an area less than 1,000 [m.sup.2] were deleted as it was observed that these smaller lake bodies were not mapped consistently across all map sheets, Island features that did not overlie lake features were deleted to remove ocean and river islands. The final inventory consisted of 241,576 lakes with 11,890 islands. Density (number of lakes per unit area) and coverage (areal extent of lakes per unit area) calculations were made using this database. Lakes that straddle the provincial border are not completely mapped. These water bodies were flagged so as not to be included in the morphometric analysis (Table 1). All large man-made reservoirs (area greater than 1 [km.sup.2]) were also flagged to be treated separately (Table2). Although there undoubtedly remain a large number of smaller artificial water impoundments in the inventory, these will be insignificant compared to the large number of natural lakes in comparably same size ranges.
The following parameters were derived from the TRIM database: lake area, lake perimeter, number of islands, island area, island perimeter, elevation, shoreline development, long-axis length and long-axis orientation. Shoreline development ([S.sub.D]) is a dimensionless parameter that represents the ratio of the length of shoreline (P) to the minimum shoreline length required to enclose the same surface area (A):
[S.sub.D] = P/[square root of ([phi]A)] (Hutchinson 1957)
Shoreline development equals 1 for a circle and increases for water bodies with a more elongated or complex (increasing number of inlets, bays and islands) planimetric shape. This index is commonly applied in aquatic habitat assessments as a proxy for bottom roughness. The long-axis orientation of a lake is the compass direction of a straight line connecting the two most distant points along the shoreline. The relation between this orientation and prevailing wind directions can significantly influence wave generation and wind-mixing dynamics of water bodies.
For carrying out the spatial analysis of lake characteristics, lake distribution, density and the frequency distributions of shoreline development and long-axis orientation were calculated on a cell-by-cell basis using an arbitrarily assigned 50-[km.sup.2] grid. This resolution was selected to provide enough lakes in most cells for statistical analysis, while still obtaining a high-enough resolution to discriminate between physiographic regions of the province. Cells with fewer than 20 lakes (28 of the 451 cells that cover the province) were excluded from the analysis of spatial morphometric trends because they often yielded anomalous statistics.
Fisheries Lake Inventory
The fisheries lake survey compiled by the Ministry of Sustainable Resource Management was also utilised in this study to allow for the analysis of hypsometric relations (specifically, lake area versus lake volume) and to make volumetric estimations of the total water stored in British Columbia lakes. Sampling density varies significantly between physiographic regions of the province (Table 3). In southern British Columbia, this partially reflects the geographic occurrence of lakes and the ease of access to them. Lakes from the northern regions of the province, however, are severely underrepresented in this inventory. The database includes basic physical lake parameters and can be obtained by electronic media directly from the B.C. Ministry of Sustainable Resource Management, Aquatic Information Branch, Fisheries Data Warehouse. These tabular files were appended and imported into a spreadsheet application. Where multiple lake records existed in the database, the most recent record was used. If the most recent record was incomplete, missing fields were updated from older records. Records that did not include measures of lake area, perimeter, maximum depth and either volume or mean depth were deleted. Mean depth ([bar.D]) was converted to a volume estimate (V) for records that did not include a volume assessment:
V = A * [bar.D]
Known man-made water bodies were flagged so as hot to be included in the hypsometric analysis. The database started with 4,019 records; however, once cleaned up (e.g., duplicates removed), the inventory consists of 2,488 water bodies. A suite of dimensionless morphometric indices was calculated for these lakes, including shoreline development (described above), relative depth (ratio of maximum depth to the diameter of a circle with the equivalent area) and volume development (ratio of lake volume to the volume of a cone with base area equal to lake surface area and height equal to maximum lake depth) (Hakanson 1981). While it would be useful to compare some of the computed values from the Fisheries Lake Inventory with those values computed from the TRIM database (e.g., shoreline development), owing to the locational uncertainty associated with the Fisheries Lake inventory records, such a comparison is unfortunately not feasible.
Water-body distribution Of the 950,000[km.sup.2] that make up the province of British Columbia, 2.37 percent of that area (22,500[km.sup.2]) is comprised of lake and reservoir water bodies. In comparison, the surface areas of Lakes Ontario and Erie are 18,900 and 25,700 [km.sup.2], respectively. With over 241,500 lakes and reservoir features greater than 1,000[m.sup.2], the average lake density of British Columbia is 0.25 lakes/ [km.sup.2]. These water bodies are distributed heterogeneously throughout the province in terms of both density (Figure 2) and relative areal coverage (Figure 3). Highest lake densities (2-15 lakes/[km.sup.2]) are observed along the Milbanke Strandflat, a low and partially submerged platform that makes up the northern mainland coast and coastal islands of the Coastal Depression. Moderate lake densities (0.12-2 lakes/[km.sup.2]) occur in all of the plateau regions of British Columbia. Low lake densities (<0.12 lakes/[km.sup.2]) are observed in the mountain systems of the province, along the western edge of the Alberta Plateau and in the Okanagan Highlands of the southeastern Interior Plateau. Areas of highest water-body coverage (10-30 percent of the land surface) include the Milbanke Strandflat and regions that contain the largest lakes and reservoirs of the province. These areas include the Yukon Plateau (Atlin Lake), the northern Interior Plateau (Nechako Reservoir and Babine and Stuart lakes), the southern Interior Plateau (Okanagan and Shuswap lakes), portions of the Rocky Mountains (Williston and Kinbasket reservoirs) and the Columbia Mountains (Arrow, Kootenay, Duncan and Revelstoke reservoirs). Areas of low water-body coverage (less than 0.25 percent of the land surface) occur mostly in the major mountain systems and the northern Rocky Mountain Foothills situated between the Rocky Mountains and the Alberta Plateau.
[FIGURES 2-3 OMITTED]
British Columbia contains sixteen natural lake bodies that are greater than 100[km.sup.2] in surface area, ten of which are situated in the Interior Plateau (Table 4). The province also contains five man-made reservoirs greater than 100 [km.sup.2] in size that have been developed for hydroelectricity-generation projects, including the Williston Reservoir, which is the largest water body of the province with a surface area of 1,728 [km.sup.2] (Table 2). Figure 4 shows the total surface area of lakes and reservoirs by size ranges spanning six orders of magnitude. Each subsequently larger lake-size category contributes a greater amount of lake area to the total surface coverage of British Columbia, despite the geometric decrease in the number of lakes occupying the larger-lake-size categories. The largest-size category (>l00[km.sup.2]) becomes clearly disproportionate with the addition of the large man-made reservoirs that account for about 47 percent of the total area of that category. Reservoirs have a decreasing influence on the distribution of surface water in the subsequently-smaller-size categories.
[FIGURE 4 OMITTED]
The shoreline development (SD) of lakes in British Columbia also exhibits some spatial and scale-related patterns. The percentage of lakes in each grid cell that have a shoreline development less than the fifth percentile ([S.sub.D] = 1.07) and greater than the ninety-fifth percentile ([S.sub.D] = 2.43) for the complete TRIM-based lake inventory is shown in Figure 5. The northwestern Alberta Plateau clearly contains an abundance of circular lakes, with over a third of the lakes in many of the grid cells exhibiting this highly circular shape. Adjacent southern and western regions of the Alberta Plateau conversely contain an abundance of lakes with high shoreline development (irregularly shaped lakes). Another region that exhibits a moderate percentage of lakes with a high shoreline development is the Milbanke Strandflat. Relations between shoreline-development statistics and lake area are illustrated in Figure 6. There is a significant positive relation between mean shoreline development and lake size class. A positive trend in the degree of scatter about the mean is also observed with larger lakes. A considerable range in shoreline development occurs at all size categories, and all distributions are moderately skewed to the right (average skewness=2.0; standard error=0.14). Some smaller lakes with exceptionally high shoreline development ([S.sub.D] > 6) are at the fuzzy boundary between being classified as a river or a lake.
[FIGURES 5-6 OMITTED]
The most common mode in the long-axis orientation of lakes throughout most of British Columbia is in the SSE-NNW (south southeast-north northeast) direction (Figure 7). This is most evident in the Rocky Mountains, the Skeena Mountains and, to a lesser extent, the Insular Mountains of Vancouver Island. Deviations from this principal pattern include a more SW-NE (southwest-northeast) orientation along the western margin of the Columbia Mountains and a near E-W (east-west) orientation in the central Interior Plateau and in several northern plateau regions. Most of the Coast Mountains and Kaska Mountains have no consistent mode of lake long-axis orientation.
[FIGURE 7 OMITTED]
Patterns in the relative depth ([R.sub.D]) and volume development ([V.sub.D]) of lakes were examined for British Columbia using the Fisheries Lakes Inventory for which depth and volume data were available (2,488 lakes). Owing to the smaller size of this database and lack of data for lakes in northern regions, spatial variability was only considered in a regional fashion. A more detailed assessment of lake morphometry using this inventory was carried out within the Cariboo, Skeena/Nass and Alberta Plateau regions by Trainor and Church (1996). The distribution of relative depth is highly skewed to the right (skewness=4.7; standard error=0.05), indicating the presence of many lakes with a high depth-to-diameter ratio. Regional analysis indicates that lakes with high relative depths are slightly more common in the Coast, Columbia and Rocky Mountains; however, this relation was not statistically significant (tested using Tukey-Kramer method, [alpha] = 0.05). No regional variation in volume development was observed in the data set. A graph showing lake volume plotted against lake area, and the associated regression equations, is shown in Figure 8. Lakes with an unlikely volume development ([V.sub.D]<0.3 and [V.sub.D]> 3) were removed from the analysis, as this database is known to contain some significant errors (100 lakes removed for volumetric analysis). The removal of those lakes from the inventory had little effect on the highly significant (P<0.001) regression result of lake volume being equal to 0.007*[area.sup.1.3]. This relation is not dimensionally balanced, indicating that volume does not increase in linear proportion to lake area. The regression result produced a reasonable fit ([R.sup.2]=0.89) for order-of-magnitude predictive purposes. Some residual structure at the large scale indicates that many of the largest lakes have greater volumes than indicated in the overall trend. Based on a similar analysis of lake depth and lake area (data not shown), the maximum depth of lakes was determined to be approximately proportional to area (0.3). Again, this result is not dimensionally balanced, with larger lakes exhibiting progressively lower relative depths. Owing to the high degree of scatter observed in the area-maximum depth relation ([R.sup.2]=0.37), its usefulness for predictive purposes is low.
[FIGURE 8 OMITTED]
Using the area-volume regression equation and the TRIM-based lake inventory, it is possible to calculate a first approximation of the total volume of fresh water stored in lake bodies in the province. For each lake in the TRIM inventory, the volume was estimated using the derived area-volume relation. For natural lakes greater than 1,000 [m.sup.2] in area, the summation of all individual lake volumes yields a total volume of approximately 312 [km.sup.3]. This estimate is only about 50 percent greater than the surveyed volume of major reservoirs of the province (209 [km.sup.3], see Table 2). The total volume of water stored in the lakes and reservoirs of British Columbia is therefore estimated to be 521 [km.sup.3]. Assuming that the area-volume relation is roughly consistent across the province, the map of lake coverage (Figure 3) could be used to approximate the spatial distribution of surface-water storage in lake bodies of British Columbia. Assessments of regional variability carried out for this study and in the work by Trainor and Church (1996) yielded inconclusive results.
Large-scale patterns in lake distribution and morphometry can be related to regional structural controls and glacial history. Areas of highest lake coverage include the major plateau regions of the province and the Milbanke Strandflat. In the plateau regions, this is due to the presence of the largest natural lakes found in British Columbia. Most of these large lake bodies appear to be elongated, glacially overdeepened basins situated along fault-controlled zones of bedrock weakness (Eyles and Mullins 1997) and are remnants of former, largely interconnected, ice-dammed Pleistocene lakes (Mathews 1944). The Milbanke Strandflat, a coastal platform cut into granitic bedrock, is a distinctive limnologic region with the highest observed density of lakes, a large proportion of which are highly irregular in shape. Strandflats are poorly understood landforms that are believed to be the product of glacial and marine erosional processes (Holtedahl 1998). Lake distribution/morphometry is constrained by the low-relief, high-roughness and indistinct drainage pattern of this coastal platform. Despite the abundance and uniqueness of lakes in this region, no significant limnological investigations have been carried out on these Strandflat lakes.
Several interesting patterns in lake distribution and mirphometry are observed in the Alberta Plateau. The western and southern portions of the plateau have the lowest lake density and coverage observed in the province. This region also contains the highest proportion of lakes with a highly irregular shape. This tract of land coincides with the location of a suspected ice-free corridor that occurred between the Laurentian and Cordillerian ice sheets (Catto et al. 1996). The scarcity of lakes in this region supports this interpretation since Pleistocene glaciation apparently has been the most dominant lake-forming mechanism in British Columbia. Most lakes situated in this flat-lying region are irregularly shaped oxbow lakes that have been produced by intermediate-sized rivers carrying a large supply of fine-grained sediments derived from remobilised glacial sediments and poorly lithified sandstone-shale bedrock to the west (Church et al. 1988). The remaining northeastern portion of the Alberta Plateau exhibits moderate lake density and coverage and contains the highest proportion of circular lakes in the province. This region is thickly mantled by glacial sediments deposited by stagnation of the Laurentide ice sheet that produced a high abundance of circular, kettle-hole lake basins.
The positive scale-related trend observed between shoreline development and lake size is probably a consequence of structural control, because the form of larger lakes becomes progressively more constrained by the dimensions of the valley that they occupy. Therefore, larger lakes will tend to be more elongated in shape. Only in the Alberta Plateau, where the influence of topographic grain is minimal, are moderately large circular lakes situated. The general SSE-NNW orientation of lakes is also likely a result of structural control. This orientation parallels the overall topographic grain of the province, a configuration resulting from the large-scale tectonic processes responsible for the buildup of the Canadian Cordillera. Lake basins that are constrained by structural features are, therefore, more likely to exhibit this preferential orientation. This is most clearly seen in the major thrust-and-fold belt of the Rocky Mountains. This pattern is confounded in the younger plutonic terrain of the Coast and Kaska Mountains where structural controls are more inconsistent in arrangement. The shape and orientation of smaller lakes are more likely to have been conditioned by glaciation. There are several areas in the central Interior Plateau and northern plateau regions where the general lake orientation parallels the dominantly E-W ice-flow directions inferred from glacial lineations in those regions (Clague 1989). Many lakes in those regions appear to occupy elongated glacial troughs constrained between adjacent drumlin landforms.
Standing water bodies can considerably influence watershed hydrology by attenuating discharge, modifying groundwater tables and energy balances and increasing residence storage rime, water temperatures and potential evaporation losses. The 521[km.sup.3] of water stored in the lakes and reservoirs of British Columbia is small relative to national standards (no national estimate is available; Great Bear Lake and Great Slave Lake alone contain over 2,000 [km.sup.3] each, and the Great Lakes of the St. Lawrence drainage contain over 20,000 [km.sup.3] of water). This volume of water, however, is of similar magnitude to the total annual discharge of all the major rivers of the province. (Mean annual discharge of the Fraser, Columbia, Peace, Liard, Skeena, Stikine and Nass rivers, which drain approximately 70 percent of the province, is 380[km.sup.3] [Environment Canada 1991]. Information presented here on lake distribution, morphometry and volume approximations is relevant to the regional hydrology of British Columbia. Furthermore, the spatial lake inventory could be used for the parameterisation of surface-water features in large-scale hydrologic models.
It is apparent that the creation of the large reservoirs in the province has significantly increased the total stored volume of surface water and greatly altered the regional distribution of surface water in British Columbia. There are many possible hydrologic consequences of this type of large-scale environmental alteration. Most studied in British Columbia have been the downstream hydrologic changes following the development and operation of the Williston Reservoir for hydroelectricity generation. Regulation of that system has created a less-variable flow regime and has reduced ice-cover formation below the dam, resulting in complex geomorphic and ecological responses far downstream (Prowse et al. 2002).
A key to sound stewardship of natural resources is a comprehensive understanding of the complexity of the biophysical matrix in which the natural resources are imbedded. While attention is frequently focused on the biological components of this matrix (see, e.g., Meidinger and Polar 1991), less attention is now given to the physical components. Through this inventory and analysis, we have documented some of the salient features of water bodies in this province. As one practical example of how these research findings could be used, the Columbia Basin Fish and Wildlife Compensation Program is currently in the process of conducting an analysis of the wetlands and lakes within their jurisdiction (Parfitt, GIS Co-ordinator, Columbia Basin Fish and Wildlife Compensation Program, personal communication). Knowing the range of lake types that occurs within their jurisdiction, and knowing where similar lake types exist elsewhere in the province, they will be better able to do paired regional comparisons and to identify particularly unique lake basins and limnologic regions of British Columbia.
A spatial lake inventory has been compiled to describe the distribution and morphometry of lakes in British Columbia. The compilation of the lake databases has allowed the following observations to be made about standing water bodies in the province:
* The areal coverage of lakes in British Columbia is 2.37 percent of the land surface area, with an average density of 0.25 lakes/[km.sup.2] (considering only water bodies >1,000 [m.sup.2] in size).
* Generally, the areal coverage and density of lakes are lowest in the northern Rocky Mountain foothills, low in the mountain systems of the province, moderate in plateau regions and highest along the Milbanke Strandflat.
* The morphometry of lakes appears to be largely related to large-scale structural controls and glacial history. Highly circular lakes are most common in the Alberta Plateau, and irregularly shaped lakes are most common in the Milbanke Strandflat and in the northern Rocky Mountain foothills. Larger lakes tend to be more elongated because of structural confinement in major valley systems. With a few exceptions, lakes in most regions exhibit a preferred orientation in the SSE-NNW direction, paralleling the overall topographic grain of the province.
* A hypsometric relation suitable for order-of-magnitude estimates of lake volume ([km.sup.3]), from known lake area ([km.sup.2]) shows that volume is roughly proportional to 0.007*[area.sup.1.3]. Northern lakes were underrepresented in this analysis, and the relation may be regionally variable.
* The total volume of water stored in lakes and reservoirs of British Columbia is estimated to be 521 [km.sup.3], with 312 [km.sup.3] (approximately 60 percent) in natural lake bodies and 209 [km.sup.3] (approximately 40 percent) in reservoirs.
The implications of these results are apparent at the regional scale. The availability of a provincially based lake inventory should play an important role in future ecosystem and water-resource management in British Columbia. The development of this inventory should also serve as an example of how large digital databases and GIS analysis capabilities may be utilised in cataloguing and interpreting landscape elements in a large-scale spatial context. The great ecological and economic importance of lakes makes them a good candidate for this type of regional characterisation and assessment.
Table 1 Lakes that straddle the British Columbia (BC) border Border Number of lakes BC area ([km.sup.2]) Alberta 46 1.70 Northwest Territories 13 0.19 Yukon * 53 117.51 Washington ([dagger]) 13 17.56 Idaho 3 0.09 Montana ([double dagger]) 4 66.97 Alaska 7 0.02 * Includes Atlin, Tagish and Teslin lakes (see Table 4). ([dagger]) Includes Osoyoos (15.02 [km.sup.2]) and Ross (2.15 [km.sup.2]) lakes. ([double dagger]) Includes Koocanusa Lake (66.87 [km.sup.2]). Table 2 Major reservoirs of British Columbia Reservoir Surface area Volume Elevation ([km.sup.2]) ([km.sup.3]) (m) Williston (D) 1,728 70.3 675 Nechako (J) 922 32.7 856 Arrow (T) 513 38.6 445 Kinbasket (M) 426 14.8 754 Kootenay (U) 423 36.7 533 Reservoir Region Hydroelectric project Williston (D) Rocky Mountains Peace River Nechako (J) Interior Plateau Alcan's Kemano Plant Arrow (T) Columbia Mountains Columbia Kinbasket (M) Rocky Mountains Columbia Kootenay (U) Columbia Mountains Columbia NOTE: Twenty seven additional reservoirs with areas ranging from 1.1 to 73 [km.sup.2] (473 [km.sup.2] in total) and volumes ranging from 0.001 to 2.1 [km.sup.3] (15.2 [km.sup.3] in total) were also identified in the survey. Table 3 Number of lakes by physiographic region for the Fisheries Lake Inventory Region Number of lakes Alberta Plateau 37 Coast Mountains 309 Coastal Depression 102 Columbia Mountains 105 Insular Mountains 251 Interior Plateau 1,305 Kaska Mountains 69 Liard Lowland 7 Rocky Mountains 223 Skeena Mountains 28 Stikine plateau 47 Yukon plateau 5 Table 4 Largest natural lakes in British Columbia (BC) Lake Surface area Maximum Volume [S.sub.D] ([km.sup.2]) depth (m) ([km.sup.3]) Atlin (B) 587 * ND ND ND Babine (F) 467 186 27 7.66 Stuart (H) 359 97 7 4.11 Okanagan (S) 350 242 26 4.31 Shuswap (P) 325 162 20 5.88 Quesnel (L) 272 ND ND 5.66 Francois (I) 254 244 22 4.54 Eutsuk (K) 251 305 29 6.21 Takla (E) 247 287 26 5.00 Harrison (R) 223 279 36 4.00 Tagish (A) 217 * ND ND ND Chilko (N) 187 366 26 3.98 Teslin (C) 148 * ND ND ND Adams (O) 132 ND ND 3.66 Powell (Q) 130 358 ND 5.47 Trembleur (G) 116 103 5 3.02 Lake [R.sub.D] VD Elevation (m) Atlin (B) ND ND 667 Babine (F) 0.76 0.89 711 Stuart (H) 0.45 0.62 681 Okanagan (S) 1.15 0.93 341 Shuswap (P) 0.80 1.14 346 Quesnel (L) ND ND 729 Francois (I) 1.36 1.07 715 Eutsuk (K) 1.71 1.05 859 Takla (E) 1.62 1.12 687 Harrison (R) 1.66 1.61 10 Tagish (A) ND ND 656 Chilko (N) 2.37 1.12 1,171 Teslin (C) ND ND 682 Adams (O) ND ND 406 Powell (Q) 2.78 ND 53 Trembleur (G) 0.85 1.18 689 Lake Region Atlin (B) Yukon Plateau Babine (F) Interior Plateau Stuart (H) Interior Plateau Okanagan (S) Interior Plateau Shuswap (P) Interior Plateau Quesnel (L) Interior Plateau Francois (I) Interior Plateau Eutsuk (K) Interior Plateau Takla (E) Interior Plateau Harrison (R) Coast Mountains Tagish (A) Yukon Plateau Chilko (N) Coast Mountains Teslin (C) Yukon Plateau Adams (O) Interior Plateau Powell (Q) Coast Mountains Trembleur (G) Interior Plateau * Area is calculated for the BC portion only. NOTE: ND, no data; [S.sub.D], shoreline development; [R.sub.D], relative depth; [V.sub.D], volume development.
The B.C. Ministry of Sustainable Resource Management supplied the raw digital data used in developing the lake inventory. We thank Mark Sondheim, Peter Freisen and Angelo Facchin for making these data available and for technical assistance. A critique of an early version of the manuscript by Dr. Olav Slaymaker helped develop this paper. A detailed review and thoughtful comments provided by two anonymous reviewers were of great value and guided further improvements.
CATTO, N., LIVERMAN, D.G.E., BOSROWSKY, P.T. and RUTTER, N. 1998 'Laurentide, cordilleran, and montane glacitation in the western Peace River--Grande Prairie Region, Alberta and British Columbia, Canada' Quaternary International 32, 21-32
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EYLES, N., and MULLINS, H.T. 1997 'Seismic-stratigraphy of Shuswap Lake, British Columbia, Canada' Sedimentary Geology 109, 283-303
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--. 1986 'Physiography of the Canadian cordillera' Geological Survey of Canada Map 1701A
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MINISTRY OF SUSTAINABLE RESOURCE MANAGEMENT 2003 Fisheries Inventory Site Government of British Columbia, Fisheries Information website. http://www.bcfisheries.gov.bc.ca/fishinv/(retrieved 28 March 2003)
NORTHCOTE, T.G. 1964 'An inventory and evaluation of the lakes of British Columbia with special reference to sport fish production' in Inventory of the Natural Resources of British Columbia (Victoria, British Columbia: The British Columbia Natural Resources Conference) 575-582
NORTHCOTE, T.G., and LARKIN, P.A. 1956 'Indices of productivity in British Columbia lakes' Journal of the Fisheries Research Board of Canada 13, 515-540
--. 1963 'Western Canada' in Limnology In North America, ed D.G. Frey (Madison, WI: The University of Wisconsin Press) 451-485
PROWSE, T.D., CONLY, F.M., CHURCH. M. and ENGLISH, M.C. 2002 'A review of hydroecological results of the Northern River Basins Study, Canada' River Research and Applications 18, 429-446
TRAINOR, K., and CHURCH, M. 1996 'Lake morphometry assessment and characterisation' Unpublished Report, British Columbia Ministry of Environment, Lands and Parks, Fisheries Branch, Victoria, British Columbia
Department of Geography, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2 (e-mail: email@example.com)
Department of Geography, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2 (e-mail: firstname.lastname@example.org)
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|Author:||Schiefer, Erik; Klinkenberg, Brian|
|Publication:||The Canadian Geographer|
|Date:||Sep 22, 2004|
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