1982-2003年中国西北地区植被动态变化格局分析

The Dynamic Analysis of Vegetation Pattern in the Northwest of China

中国西北地区属于干旱半干旱气候，植被的变化对气候和温度的变化极为敏感。植被的变化趋势在一定程度上可以反映这一地区过去的气候变化趋势并对未来的气候变化趋势进行预测。本文将1982-2003年的22年长时间系列的遥感NDVI数据分成4个阶段。分别计算各阶段的中国西北地区植被SINDVI平均值，并按不同等级生成斑块，利用景观生态学方法分析这4个时期植被格局特征以及动态变化。结果表明中国西北植被覆盖在研究期内总体是向改善的趋势发展的，局部有退化现象。

The northwest China belongs to arid and semi-arid regions. It＇s vegetation is extremely sensitive to the change of climate and temperature. The change tendency of vegetation may reflect the climatic change and forecast climatic change tendency in the future. Remote sensing NDVI data with 22 years long time series during 1982 to 2003 were divided into four periods （1982-1987, 1988-1993, 1994-1998, 1999 - 2003 ）. The average SINDVI during these four periods were calculated separately in northwest China, which was reclassified according to different SINDVI levels and transformed into patches. By using landscape ecology methodologies, the spatial pattern and dynamic change characteristics of every period patches were analyzed. The results indicate that the vegetation has increasing and improving trend mostly in northwest China. But local regions exist degenerating trend.