摘要
为研究青海省都兰县察汗乌苏绿洲植被覆盖度变化,利用归一化植被指数NDVI提取察汗乌苏绿洲不同时期的植被覆盖度等级图,定量分析评价植被覆盖度的多年变化。结果表明,近16a来,察汗乌苏绿洲植被覆盖度总体呈现波动增长趋势,2001—2006年期间各植被覆盖等级变化幅度明显高于1990—2001年期间的变化幅度,1990—2001年植被整体向好的方向发展,有50017.50 hm2的极低覆盖度植被转变为更高覆盖度植被,2001—2006年增加了6026.85 hm2的极低覆盖度植被,并有4048.47 hm2的高覆盖度植被减少,说明仍存在局部退化。影响都兰县察汗乌苏绿洲植被覆盖度变化的主要因子是生态工程措施、气候因素和水资源因素。研究结果可以为该区域植被恢复和荒漠化防治提供理论支撑。
In order to study variation of vegetation coverage of Tsagan Us oasis in Dulan county in Qinghai Province of China,the grade map of vegetation coverage in Tsagan Us oasis during different period in 1990-2006 was extracted basing on normalized NDVI data,then the interannual variation of the vegetation coverage was quantitatively analyzed.The result showed that the vegetation coverage of Tsagan Us oasis presented a fluctuating increase trend during the 16 years,and the change range of the vegetation coverage of every grade from 2001 to 2006 was greater than the one from 1990 to 2001.Generally,the vegetation coverage had a restoration trend from 1990 to 2001,and there was 50 017.50 hm2 very low coverage vegetation which was transformed to high coverage vegetation.From 2001 to 2006,there was a increase of 6 026.85 hm2 of very low coverage vegetation and a decrease of 4 048.47 hm2 high coverage vegetation,indicating local degradation of vegetation coverage.The main factors influencing vegetation coverage included： ecological recovery measures,climate change and water resource change.The research can provide a theory support for vegetation restoration and desertification combating of the research area.
出处
《中国沙漠》
CSCD
北大核心
2011年第5期1267-1272,共6页
Journal of Desert Research
基金
国家"十一五"科技支撑计划项目(2006BAD26B1001)资助
