Quantifying Land Use and Land Cover Change in Xilin River Basin Using Multi-temporal Landsat TM/ETM Sensor Data
CHEN Siqing 1,2 , LIU Jiyuan 2 , ZHUANG Dafang 2 , XIAO Xiangming 2,3 (1. Institute of Remote Sensing Applications,CAS,Beijing100101, China; 2. In stitute of Geographic Sciences and Natural Resources Research,CAS,Beijing100101, China;3. Institute for the Study of Earth,Oceans and Space,University of New Ha mpshire,Durham,NH03824, USA)
The land use/land cover change of Xilin River Basin in th e past two decades was investigated through land use/cover classificati on of four sets of Landsat TM/ETM images acquired on July 31, 1987, A ugust 11, 1991, September 27, 1997 and May 23, 2000, respectively. Primarily , 15 sub-classes land cover types were recognized, including 9 grassland types at community level: F.Sibiricum steppe,S.baicalensis steppe,A.chinensis+forb s steppe,A.chinensis+bunchgrass steppe,A.chinensis+Ar.frigida steppe,S.grandis+A .chinensis steppe,S.grandis+bunchgrass steppe,S.krylavii steppe,Ar.frigida stepp e and 6 non-grassland types: cropland, urban area, wetland, desertified land, saline-alkaline land,and waterbody. To make the time series land cover classification data applicable for land use/cover change quantif ication analysis, the cloud, waterbody and cloud shadow features were e xtracted from each of the raw land cover maps and overlaid as a subset map. Then the area corresponding to the subset in each land cover classificatio n map was eliminated. After this procedure, each of the final land c over classification map of Xilin River Basin was optimized and ready for land use/ cover change detection.The main characteristics of land use/land cover change in Xilin River Basin over the past two decades were a significant decrease in area of meadow grassland, temperate grassland vs. significant increase in area of cropland, desert grassland, urban area and desertified land. From 1987 to 2000, the area of both F.sibi ricum meadow steppe and S.bacalensis meadow steppe decreased steadily year by year, whose net decrease was 525.5 km 2 and 201.5 km 2 . While the area of S.krylavii desert steppe and Ar.frigida desert steppe increased year by year, whose net increases were 1,282.7 km 2 and 1,045.6 km 2 respectively. The desert grassland had the greatest increase in a rea, i.e., 2,328 km 2 , equal to 56% of the total area of desert grassland in 1987. The cropl and and urban area increased from 114.3 km 2 and 25.2 km 2 in 1987 to 332.1 km 2 and 43.6 km 2 in 2000, respectively. The A.lymus+ bunchgrass steppe, A.lymus+ forbs steppe had the greatest decrease in area, i.e., 2,040 km 2 .During the four periods, A.chinensis+forbs steppe was the widest di stributed land cover type in 1987 and 1991, with its area was 5281.2 k m 2 and 4104.3 km 2 , respectively. However, in 1997 and 2000, S.krylavii was the most w idespread land cover type with an area of 4,109.6 km 2 and 4,479.1 km 2 .
【Fund】： 中国科学院知识创新项目(KZCX02-308);; 美国NASA土地利用变化项目(NAG5-11160)~~
【CateGory Index】： F301.24
【CateGory Index】： F301.24