ADAPTIVE REUSE OF SHELLFISH WASTE FOR RURAL LANDSCAPE.
The coastal area of China, composed of continental coastlines and island coastlines stretching 18,000 and 14,000 km, respectively, has long been holding up half the sky in the aspects of administrative divisions and territory, economy and society, and history and culture. In the ancient times, ancestors living in coastal areas have accumulated precious tangible and intangible marine cultural heritage in the process of developing and utilizing ocean resources. As part of the marine cultural heritage, traditional rural areas featuring both agriculture and aquaculture boast special features of marine culture in the ways of building and the application of materials, composing the diversified rural cultural landscape (RCL) jointly with traditional inland agricultural villages in China. In traditional society with low productivity, shellfish waste (SW) such as oyster shells has been widely used in the construction of coastal rural areas, creating such typical RCL as "Keke Cuo" and "Oyster Shell House" (Fig. 1). As a complex landscape system well integrating the economic system, social system, and ecological system, such RCL not only reflects the humanistic and geographical features of coastal areas, but also records the trials and efforts of ancestors in changing nature and witnesses the prosperity and vicissitudes of costal rural areas (Ouyang & Huang 2012).
With the industrialization of coastal areas, the rapid development of urbanization and the fast pace of constructing the new socialist countryside, the RCL mentioned above is facing great impacts. First, the disordered development in the construction of coastal areas and the fast growth of industrial enterprises are the major causes of the increasingly serious ecological pollution in coastal areas, which threatens the integrity of marine ecology and the conservation of marine biodiversity. Second, after relocation, folks are living in monotonous and homogenous barracks-style new communities with little rural features in some traditional coastal rural areas; other rural areas with in situ dwellings are faced with the problem that newly built brick-concrete dwellings affect the characteristic landscape of traditional rural areas because of "demolition and reconstruction." Third, the annual yield of shellfish cultivation in China accounts for more than 60% of the total yield in the world, creating over 10 million tons of shell resources annually, and the number also keeps growing. As there is no timely and effective disposal, most of the shell resources turn waste or resources at low prices, which occupy shallows and land, decay, and stink, intensifying the ecological pollution in coastal areas (Fig. 2).
At present, theories and technologies for protecting Chinese rural cultural heritage are developing rapidly, and greater emphasis is being paid to the cultural heritage related to dominant and mainstream farming culture. Nevertheless, as some scholars have not included the marine culture generated in coastal zones and island areas in their recognition of traditional (rural) culture, marine culture (and nomadic culture) is often regarded as "a different force" compared with farming culture (Li 2005). In the field of research on rural cultural heritage, it is rare to see literature on the study of relationships between agricultural heritage and rural architectural heritage. The RCL with SW closely related to the farming and fishery economy has been affiliated to the scope of "sustainable landscape," but the lack of practical use and inheritance has made it become "relic landscape" in the form of "static museums," and SW also cannot be used efficiently in the construction of coastal rural areas. In the meantime, the phenomenon of "four emphases and four aspects neglected" has not changed in the practice of protecting rural cultural heritage:
* The emphasis of tourist development and the neglect of cultural preservation.
* The emphasis of large-scale demolition and reconstruction and the neglect of living updating,
* The emphasis of top-down management and the neglect of villagers' self-governance,
* The emphasis of advanced technologies and the neglect of appropriate technologies.
Against the background of pushing forward new urbanization in China, more and more attention is paid to sustainable building materials, ecological wisdom and appropriate technologies related to traditional settlements and vernacular architecture. By contrast, no scientific measures have been taken to transform those marine biological materials and relevant original building technologies once used in constructing residential environments in coastal areas, and there is still quite limited application of these materials and technologies in the field of rural cultural heritage preservation.
Shellfish waste is a renewable resource, which is abundant, cheap, environment-friendly, recyclable, and biodegradable. If it can be used and recycled "in the full life cycle, to save resources, protect environment, and reduce pollution as far as possible, to provide a healthy, applicable, and efficient space for people, and to coexist in harmony with nature," SW will be of greater ecological significance to the living cultural heritage conservation of coastal vernacular architecture and the adaptive landscape renovation of existing dwellings. Through a review of relevant studies at home and abroad, there is still a gap in the application study of SW in relation to the protection of vernacular architecture, renovation of cultural heritage, and design of sustainable architecture.
Modern Applied Technologies Related to SW Reuse
In recent years, studies on SW such as oyster shells are gradually increasing in the fields of medicine, food, agriculture and light industry, and rapid progress can be seen in studies on technologies of harmless disposal and recycling as resources in the field of cultivation (Miao et al. 2011). Some typical shell-recycling programs include mussel shell recycling as a soil amendment (Lvarez et al. 2012) or to fight fluoride pollution (Quintans-Fondo et al. 2016), oyster shell waste treatment using the plasma pyrolysis technique (Chae et al. 2006). Nevertheless, none of the existing technologies on using SW have tackled the problems of inefficient resource utilization and high cost of use. It is hard to deal with tens of millions of tons of SW within a short period of time by using these technologies. Moreover, most of such technologies have to rely on superfine grinding and physical modification (Chen et al. 2008), resulting in high cost and secondary pollution because of the discharge of organic wastewater of high concentration and high salinity (Seco-Reigosa et al. 2014). Therefore, the study and development of new SW reuse technologies are of certain theoretical significance and innovative value, and can bring economic benefits.
The major composition of oyster shells is calcium carbonate, usually accounting for 90% of the mass of each shell, which is much higher than the 80% calcium carbonate in ordinary limestone, so high efficiency can be achieved if oyster shells are used in the production of calcined cement. Through calcination at 700[degrees]C-1,000[degrees]C in air atmosphere with a heating rate of 10[degrees]C/min for 4 h, the dried oyster shells can be made into natural shell calcium oxide powder, which was sieved to pass 100-200 mesh screens (Buasri et al. 2013). So, it shows prospects of wide application and great market potential. Its excellent material performance is mainly embodied in two aspects. First, it boasts a good absorptive property. By making experiments, Kim et al. (2007) proved that a proper amount of oyster shell powder added to common paint could absorb volatile organic compounds such as methanol, functioning as an ideal carrier for material adhesion and a biological resource causing no pollution. Anderson et al. (1996) studied the effect of preventing wall surfaces from mildewing in moist conditions after oyster shell powder was added to interior wall paint. Second, it features good conditioning capability. The research made by Yang et al. (2010) showed that it not only had little impact on the long-term strength of concrete but also could significantly improve the resistance to freeze-thawing and water penetration, after 10% of oyster shell powder was added to high-strength concrete. Existing studies have shown the combination of SW mainly composed of calcium carbonate and modern applied technology. Nevertheless, these ways of application make products low value-added and too expensive, and are not suitable for popularization in the vast coastal rural areas.
Adaptive Reuse of Vernacular Architecture
The most typical vernacular architecture related to oyster shells includes the "Keke Cuo" at Xunbu village in Quanzhou and the "Oyster Shell House" at Xiaozhou village in Guangzhou, as well as the practice of plastering external walls of traditional dwellings with the mixture of shell debris, soil, and mud in many coastal areas. They boast the good properties of thermal insulation, structural stability, waterproofing, and sound insulation, and the typical characteristics of marine culture. Nevertheless, the traditional ecological building experience spontaneously generated through long-term evolvement failed to be "reused adaptively" in modern coastal rural areas. The key to its "adaptive reuse" is how to creatively find the compatibility of traditional vernacular architecture and new modern architecture and retain the cultural characteristics of traditional architecture. Rapoport (1969) held that the most effective way was to make traditional ecological building experience scientific, and reuse them with the method of "models and adjustments" and proper technical strategies, based on the inheritance of authenticity. Chinese scholars represented by Liu (2003) studied the renovation and transformation of vernacular architecture such as cave dwellings in northwest China, realizing the scientific transformation of traditional building experience such as insulation and energy saving. The natural carriers of RCL are living things which are growing and changing, and the external shapes of the carriers can be altered by natural laws. Western scholars with Hassan Fathy as a representative further explored the feasibility of publicizing low-cost rural architecture in vast rural areas, and advocated the inheritance and development of traditional building technology and giving local villagers instruction in self-help construction. Therefore, in addition to conserving the physical state of vernacular architecture with modern technology, it is more important to inherit the ecological wisdom in vernacular architecture, and the core value of inheriting RCL lies in living cultural heritage protection.
Association Studies of RCL and Agricultural Heritage
According to the definition and categories given by the World Heritage Center in 1992, "cultural landscapes fall into three main categories, namely the landscape designed and created intentionally by man, the organically evolved landscape, and the associative cultural landscape." In these categories, organically evolved landscapes fall into two subcategories, namely the relict (or fossil) landscape and the continuing landscape. Rural cultural landscapes generally integrate "production, life, and ecology," so are closely related to the culture of agricultural production. In 2012, 2014, and 2015, the government of China issued Important Chinese Agricultural Heritage List in three batches, including 61 items. It means the traditional agricultural production system created by ancestors in history and inherited in living forms is protected by the government. As part of marine culture, coastal rural buildings such as "Keke Cuo" are the crystallization of nature and humankind created by ancestors in the process of effectively using shellfish resources and reusing SW, and cultural landscapes with prominent features of coastal rural areas. They resulted from the most primitive social and economic needs, and developed into the current state through relationships and adaptation to the surrounding natural environment. As clues and evidence of the development of typical agricultural and fishing industries in China, these are still playing an active social role in local villages. Nevertheless, because of changes in the ways of production and living and special historical reasons, the features of these buildings have not evolved continuously. Moreover, some have been seriously damaged, becoming a "relict landscape." Such "absence of evolvement" also directly results in the failure to effectively use large quantities of marine bio-materials in modern architectural design. It was mostly against the background of different environmental pressure that an ecological interrelation was established between RCL and agricultural heritage, which made ancestors inhabiting in coastal areas constantly adjust their relations with the natural environment, thus forming a "continuing landscape" in the traditional society. The logic also conforms to the requirement that "agricultural heritage is living heritage integrating the productive, ecological, and cultural functions" (Zhu & Zhao 2014). As a new type of heritage, agricultural heritage not only has exclusive agricultural properties, but also emphasizes constructing a harmonious and living symbiotic system for humankind and the earth. Therefore, it is needed to establish a living and systematic mechanism of guarantee and promotion, making existing RCL become valuable agricultural heritage.
Background of RCL Formation
The coastal waters in East China and South China are suitable for the growth of shellfish, so shellfish resources are everywhere during each harvest season. Through archeological research, large numbers of shell mound sites have been found in the coastal areas such as Fujian, Guangdong, Shandong, Guangxi, and Liaoning in inland China, which suggests that the use of shellfish resources has begun because human civilization emerged in coastal areas. According to relevant studies on the Pearl River Delta, it is inferred that ancestors could overcome the influence of transgression and publicize the techniques of filling in the sea and creating farmland, for which the major reason was that they found and used the shell mound sites under "tidal land." Building dams based on shell mounds can protect farmland and rural residences from the impact and erosion caused by waves and wind, and the shell resources in shell mounds can also be used to build dwellings, with the "Oyster Shell House" at Xiaozhou village in Guangzhou as the most typical example (Wang & Zhao 2017). Different from the "Oyster Shell House," oyster shells in the "Keke Cuo" at Xunbu village in Quanzhou came from "the Maritime Silk Road," originally used as ballast for making ships heavier during voyages in ancient times (Xu et al. 2013). In 1604, when an M8.0 earthquake happened in the Donghai district of Quanzhou, large quantities of oyster shells abandoned near Xunbu Port and rubble in the ruins were used together as materials for building external walls in the reconstruction of communities. Besides, in other coastal areas, it is more frequently seen that the tamped mixture of shell debris, soil, sand, and mud is used for building walls, or mixed mortar is used to plaster external walls. This is related to the lime generated by oyster shell calcinations, which can improve the quality of acid soil in Guangzhou. The earliest record of lime was made by Zhou Li (Rong 2011), and Song of the Ming Dynasty described the scene that ancestors living in coastal areas excavated and calcined oyster shells to obtain lime in T'ien-kung K'ai-wu (Fig. 3).
Material Properties of Oyster Shells
Traditional vernacular architecture such as "Keke Cuo" has been widely accepted for good structural stability, thermal insulation, and material durability in the space-time evolvement for more than 500 y. It is rainy in coastal areas, where buildings are buffeted throughout the year by strong wind with high salinity. Although the surface of oyster shells is eroded to some extent, the buildings still retain complete structural features. These appearance features cannot be separated from the use of oyster shells as building materials. The basic structure of an oyster shell is divided into three layers. The outermost layer is a wrinkled cuticle which is rather thin and can resist oxidation and erosion; the prismatic layer in the middle is the major component of an oyster shell, which is made of interweaving calcium fiber light in weight and of high strength, with many interconnected natural vents, so is absorptive, sound-absorbing, catalytic, and decomposable; the innermost layer is a pearl layer composed of minerals like calcium carbonate and small amounts of organic matter, with the properties of high density, acid resistance, alkali resistance, and durability. In addition, a complete oyster shell performs well in air tightness and thermal insulation, because the air layer in its empty cavity flows slowly. The thermal testing of the external walls of the oyster shell house proved that the heat transfer coefficient of oyster shell walls was small and the attenuation and delaying effects of temperature and heat flow were rather obvious (Liu et al. 2012).
Another material property of oyster shells is mainly embodied in that traditional sticky rice mortar, a mixture of proper amounts of oyster shell powder and sticky rice, performs excellently in bonding strength, toughness, and impermeability, and it has become an extremely important binder in the construction of traditional vernacular architecture, which was recognized as one of the important technical inventions in the history of ancient Chinese architecture (Yang et al. 2009). Although perishable, natural polysaccharide substance was added to it, the mortar composed of oyster shell powder still has resisted decay in the past thousands of years, which is mainly because the lime in it has undergone the following chemical reactions:
CaO + [H.sub.2]O = Ca[(OH).sub.2] (1)
Ca[(OH).sub.2] [right arrow] [Ca.sup.2+] + 2O[H.sup.-] (2)
Reaction 1 is the digestion of CaO in water, which generates Ca[(OH).sub.2] and emits heat. Research shows Ca[(OH).sub.2] produces active oxygen that has an extremely strong effect of killing bacteria in the process of digestion. Reaction 2 is the ionization of Ca[(OH).sub.2], in which two kinds of ions are generated, namely [Ca.sup.2+] and OFT. Existing studies have proved that a highly alkaline environment can inhibit and kill bacteria. In the solidification process of sticky rice mortar, Ca[(OH).sub.2] undergoes the following chemical reaction:
Ca[(OH).sub.2] + C[O.sub.2] = CaC[O.sub.3] + [H.sub.2]O (3)
In this reaction, Ca[(OH).sub.2] reacts with C[O.sub.2] in air and generates CaC[O.sub.3]. With the progress of Reaction 3, more and more CaC[O.sub.3] is generated, and the sticky rice mortar gradually solidifies, gaining higher strength. In sticky rice mortar, the amount of C[O.sub.2] infiltration is restricted, so complete solidification is a long process. Before the complete change of Ca[(OH).sub.2] into CaC[O.sub.3], Reaction 2 always exists and maintains the highly alkaline environment needed for inhibiting the growth of bacteria. Further research shows that organic components such as sticky rice and lime are crucial in traditional mortar, playing a major role in improving the bonding strength of mortar, whereas soil and sand basically function as filler.
Techniques of Building External Walls
Although they were both built mainly with oyster shells, the external walls of "Keke Cuo" and "Oyster Shell House" show roughness and exquisiteness, respectively, because of different building techniques (Fig. 4). To guarantee the stability and waterproofing effect of walls, the wall footing of the former was usually built by laying heavy granite blocks slantwise or horizontally, looking solemn and rustic; the latter was mostly built by horizontally laying granite obtained from shipping transportation, where the practice of slantwise laying was rarely seen. The parts above the wall footing were both built by filling rammed soil and rock debris in historic rammed earth construction. When fixed on the surface of external walls with sticky rice mortar, oyster shells were usually laid slightly tilting downward to drain rain water, thus avoiding scouring, water accumulation, or even leakage. It seemed that the oyster shells in "Keke Cuo" were not selected by size or by following any rules, but it was found after careful analysis that the big shells were laid in stretcher bond (the overlap, which is usually of half the length of the object) whereas the small ones were laid in bull header bond (the overlap, which is usually of half the of width of the object). The oyster shells used in "Oyster Shell House" are mostly the same in size and about 20-30 cm wide, which were strung with durable rattan ropes, of which the display mode unifies with the large, uplift, and triangular shells above and the other small and flat ones below.
The lower and upper shells were placed row by row in header bond to build a single-layered wall, or combined side by side to build a double-layered wall, both showing clear and obvious horizontal lines. If the height of a wall had surpassed a certain limit (often on the load-bearing gables), "a fir framework" would have had to be erected in the middle of the wall to provide support, the role of which was as the structural columns in modern brick-concrete structures. If the length of a wall had exceeded a certain limit, stone or wood columns would have had to be used to segment the wall, so as to improve its resistance to collapse. After completed, the internal surface of walls was often plastered with mortar and made flat, and the thickness of a wall can reach up to 60-80 cm.
Traditional Construction Method
After the existing broken external walls of "Keke Cuo" and "Oyster Shell House" were dissected and analyzed (Fig. 5), the typical structures of them were defined respectively. From inside to outside, the walls of "Keke Cuo" in Quanzhou are made up of 15 mm facing oyster shell mortar, 25 mm leveling mortar mixed with straw, 300-400 mm internal wall infilled with brick and rock debris, 30 mm rendering oyster shell mortar and 70-80 mm oyster shells laid in stretcher or bull header bond. The structure of "Oyster Shell House" in Guangzhou also includes several layers from inside to outside, namely 15 mm facing oyster shell mortar, 25 mm leveling mortar mixed with straw, 200-300 mm internal wall infilled with soil and gravel, 30 mm rendering oyster shell mortar and 200-300 mm oyster shells laid in bull header bond with joints unaligned. It can be seen that in the two structures, the outside of the base course wall was covered with oyster shells as facing materials, which were laid layer by layer with joints unaligned according to the traditional process of building plain brick walls.
From the perspective of engineering thermodynamics and heat transfer, it is for the following reasons that "Keke Cuo" and "Oyster Shell House" can keep warm in winter and cool in summer.
Thermal Insulation Performance in Winter
Thermal Insulation Performance of Materials: Based on the study of literature, oyster shell density varies from 1,710 to 1,940 kg/[m.sup.3], and heat conductivity coefficient varies from 0.9 to 2.27 W/m-K (Wheaton 2007). In comparison with cement mortar of which the density is 1,800 kg/[m.sup.3] and heat conductivity coefficient is 0.93 W/m-K, it can be seen that oyster shells are similar to cement mortar in thermal performance, and not insulated against coldness.
Air Interlayer: The oyster shells from traditional RCL are not collected from processing or shell piles. They come separately from "tidal land" (Oyster Shell House) and ballast for shipping (Keke Cuo). Most of them are alive and have both valves in place, so they can use whole as building material. In the process of use, oysters will die and the dead oysters will decay and finally disappear inside the shells, so the layer of oyster shells outside the walls can be regarded as a relatively airtight air interlayer. The air in oyster shells is confined in an empty cavity, functioning as a buffer layer when heated in the day, and lessening the convection and radiant heat loss at night in winter. The thermal insulation effect of oyster shells can be approximately regarded as the addition of an air interlayer with the thermal resistance of 0.11 [m.sup.2][??]K/W.
To sum up, the oyster shell facing can achieve a certain effect of thermal insulation, but the effect is limited.
Thermal Insulation Performance in Summer
Sunshade: The oyster shells laid unevenly in traditional external walls are similar to small-sized sunshading facade structures, so can function as sunshades to some extent. In the process of laying traditional external walls, it is reasonably determined how the extended length (L2) of oyster shells should be related to the vertical distance (D = D1 + [D.bar]2) between upper and lower oyster shells according to the local solar altitude and the orientation of buildings. In Guangzhou, for example, the solar altitude is larger than 80 deg in summer, so the limit of D [less than or equal to] 5.7 L2 should be met when laying oyster shells. Field investigation shows that both "Keke Cuo" and "Oyster Shell House" with oyster shells laid either in stretcher or bull header bond meet the requirements of walls functioning as sunshades.
Radiant Heat Dissipation: The characteristics of oyster shell external surfaces and the method of laying oyster shells increase the area of contact between such external walls and air. In other words, the area of radiant heat dissipation is increased at night in summer, which facilitates the cooling and heat dissipation of buildings at night. In the meantime, there are tiny holes on the surfaces of oyster shells, which can accumulate natural rain water and achieve lower temperature through passive evaporation. Based on the study of literature, porous facing bricks with a high rate of water absorption perform well in lowering temperature and saving energy, and the heat flow into rooms reduced by such bricks is 9.1 % more than that reduced by cement mortar, and 98% more than that reduced by ceramic tiles (Yao 2014). Therefore, the porous feature of oyster shell external surfaces can greatly facilitate the cooling of internal surfaces of walls in summer.
To sum up, oyster shell walls can achieve significant cooling effect in summer, effectively reduce the radiant heat absorbed by external wall surfaces in the day, and accelerate the heat dissipation of walls, to lower indoor temperature.
The Application of New Landscape Structure
The use of oyster shells in the external walls of rural buildings can be divided into two main situations. First, in the external walls (especially the east and west gable walls of quadrangle dwellings) of existing brick-concrete dwellings generated because of "demolition and reconstruction," they are used for the purpose of improving traditional rural landscape and thermal performances; second, in the external walls of newly built rural buildings, they are used in consideration of creating an atmosphere for new-type coastal rural areas. Therefore, in the process of using oyster shells, the principles to be followed should include the following: keeping original patterns and texture, giving full play to the properties of functioning as sunshades and cooling, and properly increasing insulation construction measures.
For the convenience of using general ways of building in modern construction, after collected and sorted, oyster shells are made into prefabricated oyster shell parts in rural factories. During on-site construction, these prefabricated parts are connected with external walls through "structural addition," forming a kind of compound wall structure made of recycled resources. In the process of making prefabricated part specimens (Fig. 6), a complete compound specimen of oyster shells and mortar can be produced only by finishing the procedures of collecting oysters, sorting them by size, casting frames, preparing mortar, manual laying, etc. In the process of specific application, two kinds of new landscape structures are produced experimentally in accordance to the regional differences and in combination with the requirements of industrialization (Fig. 7).
One is integrated external wall boards for architectural ornament and cooling. A layer of oyster shells is compounded and connected with the surface of a prefabricated concrete wall board. The finished oyster shell wall boards are hung onto the external walls of buildings with metal parts, achieving the effect of sunshade and cooling whereas maintaining the original landscape.
The other is external sunshade parts for outer windows. According to the practice of making sunshade blinds, oyster shells are vertically strung together on steel wires, to reduce the direct sunlight through windows and cool the hot air flowing into rooms by evaporative cooling.
SUSTAINABLE LANDSCAPE SYSTEM ENGINEERING
The use of new landscape structure as architectural products realizes the adaptive reuse of SW in RCL. Moreover, from oyster breeding to component production and to rural construction, the process embodies the typical features of "continuing landscape" in rural areas featuring both agriculture and aquaculture. Therefore, it is most realistic to explore and improve the landscape value of SW based on reshaping the whole ecological space of agricultural heritage.
From the circulation of SW between mariculture zone and rural areas (Burrell 2003), it can be seen that the process is comprehensive and holistic system engineering (Fig. 8), so its designing research programs need the theoretical model of system engineering. Hall put forward a three-dimensional spatial structure composed of time dimension, logical dimension, and knowledge dimension. He divided system engineering into seven stages with close connection and pointed out that each stage should have a technical support (Wang et al. 2015). In the process of reusing SW, time dimension can be set at seven stages, namely offshore cultivation, wharf trade, oyster processing, shell sorting, component production, and product delivery. Logical dimension refers to the work content and the following thinking process in various stages, including analyzing problems, identifying goals, system analysis, system integration, optimization, decision-making, and implementation of logical steps. The knowledge dimension is the related knowledge and technologies used to achieve ecotransformation.
With the design research on a coastal village as an example, the promotion mechanism of "mariculture zone-factory-site" is studied (Fig. 9). In the stage of offshore cultivation, the breeding, raising, and catching of economical shellfish can be considered and combined with rural tourism. In other words, with the coastal sheds and frameworks for cultivation as a starting point, "corridors" are built on top, to develop recreational fishery tourism for travelers to appreciate oyster cultivation within a short distance and taste fresh oysters. In the stage of oyster processing, by wheelbarrow, some of the oysters are carried back to fishermen's household workshops, and some are delivered to the community square for tourists to experience the process of shelling oysters by hands; oysters transported by conveyor enter Shell Reusing Technology Incubation Factory, and are processed with modern processing technology. In the stage of shell sorting, large quantities of oyster shells generated in the last stage are sorted into different shell piles by size, with the small ones grounded for producing mortar or paving roads, and some of the big ones returned to the mariculture zone for other purposes of use and others all used for making landscape constructions. In the stage of producing constructions, not only professional workers but also villagers and tourists can participate to personally experience the revitalization of farming and fishery cultural heritage through the reuse of SW. In the stage of product delivery, labeled cans are shipped out, and landscape constructions are added to structures in the construction of local rural areas or other coastal rural areas.
In conclusion, to realize the goal of adaptively reusing SW in Chinese coastal RCL, the planning idea of sustainable landscapes should be followed. Only in this way can the following goals be truly fulfilled, including renovating the rural environment, inheriting farming and fishery culture, expanding agricultural functions, and inspiring the low-cost construction of the beautiful countryside. This study tries to provide a living cultural heritage system and a possible future model of cultural development for the sustainable development of coastal rural areas in China, to insert SW again in the ecological chain of material circulation in the farming and fishery economy on the premise of keeping authenticity, and to make original RCL with SW resources continue to maintain economic vitality. The study of agricultural heritage from the perspective of residential environment should not only involve isolated surveys on the process of agricultural production but also lay more emphasis on the integrated study of the production process of farming and fishery and the life of villagers, to reshape the relations between agricultural production and life and ecology, as well as the relations between rural areas, nature, and agriculture, which should be the key to solving the problem of sustainable development of residential environments.
This research was supported by the National Natural Science Foundation of China (Grant No. 51408343, Grant No. 51378301), State Key Lab of Subtropical Building Science, South China University of Technology (Grant No. 2017ZB10), Shandong Provincial Natural Science Found, China (Grant No. ZR2013EEQ017). The authors would like to thank Guangkun Mu, Wenshuang Zhao, Lukun Tang, Shuo Chen, Tinglu Dong, Shaogang Zhang, Kunheng Han, Yajing Cui, Binyue Guo (Shandong Jianzhu University), for their participation in this research.
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JIANG WANG, (1,2,3*) JILONG ZHAO (1) AND QIANMIAO YANG (1)
(1) School of Architecture and Urban Planning, Shandong Jianzhu University, Fengming Road, Lingang Development Zone, Jinan, 250101, Shandong, China; (2) State Key Lab of Subtropical Building Science, South China University of Technology, Liwukejidalou, 381 Wushan Road, Guangzhou, 510640, Guangdong, China; (3) School of Architecture, University of Miami, 1223 Dickinson Drive, Coral Gables, FL 33146
(*) Corresponding author. E-mail: email@example.com
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|Author:||Wang, Jiang; Zhao, Jilong; Yang, Qianmiao|
|Publication:||Journal of Shellfish Research|
|Date:||Dec 1, 2017|
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