| Land-use/cover change (LUCC) and its spatial behavior have Influential and constraints of regional economic and social development, regional urban and rural spatial layout and development trends, and sustainable development with the sur-rounding areas, which is the core content of the regional variation. The strengthening of human activities on natural and social environment in time and space is produced in a far-reaching impact. LUCC and its spatial behavior characteristics are reflected the impact of human activities on natural economic and social from the surface evolu-tion and the development trend. Research on LUCC and its spatial behavior charac-teristics can reveal the regional land-use changes in time and space, which is great significance for harmonious development of nature, economic and society, harmoni-ous development of protecting the ecological environment and developing natural en-vironment, harmonious development of the relationship between people and land.We have the large population and the poor available land resources, which is one of China’s basic national conditions. The contradiction between population and land in a long period always restricts China’s rapid economic development, which has also brought new challenges for sustainable development of the regional economic and society. This article selects Dongjiang Region, located in the Pearl River Delta Region, which has great population density, rapid economic development and obvious contra-diction between people and land. The research area belongs to developed coastal areas as first developed in China’s reform and opening up. LUCC and its spatial behavior characteristics of the area can represent the realities by China’s economically devel-oped eastern region, which can provide a good guide and lessons learned for the rela- tively backward regions of western China.In this paper, the research area includes Taoxi river basin, Shuntian river basin, Lantang river basin, Jiuzhou river basin, Xinfeng river basin and Yuecheng river basin, which are all in Dongjiang Region. The total area of the research area is402067.32ha. Source data for the study are vector data sets, which are70-73(70s),86-88(80s),91-94(90sf),97-99(90sl) and02-03(20s) period of land-use types. After registering and classifying date sets, the Dongjiang Region LUCC spatial database is established.Based on the Dongjiang Region LUCC spatial database, this paper conducts a quantitative analysis of LUCC in amplitude, single dynamic, Comprehensive dynamic and land-use types into each other trending on the research area by the method of spa-tial statistics, spatial filtering, spatial overlay (cut) with GIS. By the analysis of Dongjiang Region land-use dynamic change, potential patterns and trends of LUCC have been found, which further reveals the intrinsically linked and complexity in LUCC on the research area. Studies have shown that:In single land-use dynamic change:(1) As the largest area land-use type, proportion of wood land’s area had always been maintained at more than58%. During70s-20s wood land’s area showed a trend of substantial growth year after year and then slightly reduced, which was the types of the largest growth of area in all land-use types. A total accumulated increase was63253.87ha. The main source of new wood land was from unused land and agricul-tural land.(2) During70s-20s unused land’s area showed a trend of pre-continuous decline and the late modest growth, whose area was accumulated reduction of56666.02ha. Unused land was the types of the largest reduce of area in all land-use types. The main source from unused land converted was wood land and agricultural land.(3) During70s-20s agricultural land’s area was continue to decrease, area pro-portion of which was from20.52%in the70s to17.88%in the20s. Agricultural land’s area decreased10646.07ha (annual decreased417.49ha) and the single dynamic was-0.51%. It was the only land-use type that had been continue to decrease.(4) During70s-20s construction land’s area was continue to increase, area pro-portion of which was from0.07%in the70s to0.99%in the20s. Construction land’s area increased3688.38ha (annual increased144.64ha) and the single dynamic was52.21%. It was the one that have the highest dynamic degree and the fastest growing speed in all land-use type. The main source of new construction land was from agri-cultural land, unused land and wood land.In Comprehensive land-use dynamics change and land-use conversion trend:(1) During70s-20s, Comprehensive land-use dynamic change of research area had gone through three stages of development:①During70s-90sf, there was a con-tinued growth in the speed of comprehensive land-use dynamics change because of non-construction land converting to construction land. Comprehensive land-use dy-namic degree rised from1.25%in70s-80s to2.00%in80s-90sf. Especially the LUCC comprehensive land-use dynamic degree of80s-90sf was the highest values in the70s-20s.②During90sf-90sl, New construction land was decreasing, because the area from agricultural land, wood land and unused land to construction land was reduced. In this period the speed of comprehensive land-use dynamics change was1.31%.③During90sl-20s, The subject was economical and intensive using land and protection the basic farmland. Based on the new land-use planning, the growth of construction land’s area was restricted. Converting from agricultural land, wood land and unused land to construction land led to the rise of the speed of comprehensive land-use dy-namics change. Until20s, the speed of comprehensive land-use dynamics change was1.89%.(2) During70s-20s, land-use conversion in size were mainly unused land-wood land conversion, agricultural land-wood land conversion and unused land-agricultural land conversion; land-use conversion in speed were mainly agricultural land-construction land. In research period, planting trees on wasteland was the main form of unused land-wood land conversion. About77.10%of unused land converted into wood land through afforestation. Returning farmland to forest was the main form of agricultural land-wood land conversion. About24.33%of agricultural land con-verted into wood land through returning farmland to forest. Wasteland farming was the main form of unused land-agricultural land conversion. About11.90%of unused land converted into agricultural land through Wasteland farming. Agricultural land in the surrounding of urban settlements occupied by construction was the main form of agricultural land-construction land. About3.63%of agricultural land converted into construction land.Based on fractal theory and quantitative geography, this paper further analyses the changes in the spatial behavior characteristics of LUCC in the past25years in or-der to reveal the nature and trends of spatial behavior characteristics. Studies have shown that:(1) During70s-20s the average fractal dimension showed a trend of slow growth and then decreased slowly. This shows that LUCC of research region was from com-plex, irregular trend toward a unified direction under the guidance of the policy and planning, which experienced a process from stable to unstable, and then back to stable. Among all land-use types, by the weakest human interference waters had the maxi-mum fractal dimension and the worst stability because of criss-crossing water nets and lakes. By the strongest human interference construction land had the minimum fractal dimension and the best stability because of minimum land area, regular layout and standard expansion trend. Because of planting trees on wasteland and wasteland farming, area of unused land had a strong decrease, land patches of which were dis-membered and broken. So its fractal dimension had great changes.(2) During70s-20s Diversity index (SHEI) showed a trend of rising slowly first and decline rapidly. SHEI value was the highest in the70s and the lowest in the90sl. And then there was a slight rebound. As space fragmentation from high to low land-use types were construction land, waters, unused land, agricultural land and wood land. By the strongest human interference construction land had the highest spatial fragmentation because new construction land patches were broken and scat-tered. Agricultural land and wood land had lower spatial fragmentation because of larger land patch area, better stability and internal homogeneity.In summary, through spatial database organization method, GIS spatial statistical analysis, fractal theory and quantitative geography, this paper reveals nature and trends of LUCC in Dongjiang Region. It provides a long time, wide range research on LUCC, which common short-term artificial FNEC can not express and reveal. It pro-vides a precise mathematical models and quantitative analysis conclusions for LUCC, which provides the appropriate reference and reliable data on the region’s economic development and ecological protection. |
PDF Full Text Request