Spatial-temporal Variation and Dynamic Evolution of the Cultivated Land in Shiyang River Basin from 1973 to 2010

Land use / cover change affect the ecological environment and the sustainable development of social economy,has become research hot topic at home and abroad in recent years,and the cultivated land change is one of the important contents of research of land use. Taken the cultivated land of Shiyang river Basin which was the typical fragile ecological region as the researching subject,using remote sensing( TM,MSS and CBERS),the information of land use / cover variation( LUCC) in 1973,1987,1994,1998,2005,and 2010 was reconstructed based on GIS technique. The result showed during the past 30 years,1 The cultivated land area of Shiyang river basin had increased,and the increased area mainly distributed in the middle and lower reaches. 2 Viewed from the dynamic characteristics,1990's was the most area increasing and variation intensify period. In recent years,the middle and lower reaches of cultivated land area was steady,even got smaller some time. 3 The center of cultivated land had shift to the northeast. 4 The degree of fragmentation and importance value had increased gradually,but the separation degree had decreased slightly. Population increase,national policy change of and water resources were the major reasons for the dynamic change of cultivated land in Shiyang river basin. The quantitative analysis of cultivated land temporal and spatial variation and driving factors in Shiyang river basin was helpful research the relationship between the cultivated land change and nature,ecological processes and the human social activities in inland river basin in further,provided important scientific evidence for the sustainable development of the study area.