摘要
以GIMMS NDVI3g数据为基础,利用像元二分模型和Intensity analysis方法,从时间间隔、植被覆盖度等级变化和转换3个层面分析了1982─2010年内蒙古植被覆盖度的变化。结果表明:由像元二分模型估算的植被覆盖度与实测值有较高的相关性(0.914)。1980s─1990s植被覆盖度增加的面积(49.2%)大于其减少的面积(43.3%),而在1990s─21世纪初植被盖度减少的面积(57.1%)大于增加面积(35.6%),表明1990年代的植被长势比其他两个年代好。1990s─21世纪初的植被年平均变化速率相对1980s─1990s较快。1980s─1990s,高植被覆盖度的增加活跃,减少较平缓,而低植被覆盖度的增加和减少均较平缓;1990s─21世纪初,高覆盖度和低覆盖植被的增加较平缓,而减少变化较为活跃。研究期内低覆盖度植被以向高一等级转变为主,而高覆盖度则以向低级转换为主。
In this paper, based on the GIMMS NDVI3g data, using dimidiate pixel model and intensity analysis methods to analyze the changes of vegetation coverage in Inner Mongolia from 1982 to 2010 at three levels as time interval, category and transition. The results show that the vegetation coverage estimated by dimidiate pixel model has a high correlation with the measured values, which up to 0.836. The vegetation coverage’s increased area （49.2%） is greater than the reduced area （43.3%） from 1980s to 1990s, while in 1990s to the 21st century the reduced area （57.1%） is greater than the increased area （35.6%）, indicating that the vegetation growth in the 1990s is better than the two other decades. From the intensity analysis we can see that the average annual rate of change in the 1990s-early 21st century was relatively faster than that of the 1980s-1990s. In the 1980s-1990s, the gain of high vegetation coverage was active and the loss was dormant; the gain and loss of low vegetation coverage was both dormant. In the 1990s-early 21st century the gain of high and low vegetation coverage both are dormant, while the losses were active. In two study periods, the low coverage of vegetation transition to a higher level, however the high vegetation coverage is converting to the lower coverage.
出处
《生态环境学报》
CSCD
北大核心
2016年第5期737-743,共7页
Ecology and Environmental Sciences
基金
国家科技支撑计划子课题(2013BAK05B01)
国家自然基金项目(41461102)
关键词
植被覆盖度
像元二分模型
强度分析
时空变化
vegetation coverage
dimidiate pixel model
intensity analysis
spatiotemporal changes
