基于SPOT VEGETATION数据的关中地区近10年来植被覆盖变化分析

利用SPOT VEGETATION1998.4-2007.12的NDVI（Normalized Difference Vegetation Index,归一化植被指数）数据,结合地理信息系统技术,对我国关中地区的植被覆盖情况进行了动态监测。采用最大化合成法、均值法、一元线性回归分析和R/S分析法分析了关中地区近10a来各地区、各土地利用类型的NDVI变化特征和变化趋势。分析结果表明：近10a来关中地区年均NDVI值整体呈增加的趋势;渭南市的年均NDVI最低;各土地利用类型的Hurst指数均在0.5～1之间,即为可持续性序列,耕地、草地、水域等有持续性增加的趋势,但是林地NDVI值有持续性减小的趋势,须采取一定的措施防止林地退化。

Analysis on the Change of Vegetation Cover in Guanzhong Based on SPOT VEGETATION Data during the Past 10 Years

A time series of SPOT-VEGETATION Normalized Difference Vegetation Index （NDVI） data with 1km ×1 km spatial resolution were used to monitor the vegetation cover change during 1998 to 2007 in Guanzhong.The MVC （Maximum Value Composites） method,the mean method,the linear regression and the R/S analysis method were used to characterize the trends in vegetation cover change,including every region and variety of different land use types.The results showed that the annual NDVI was generally persistent and a rising tendency during the past 10 years in Guanzhong.The min-NDVI was in Weinan city,Hurst exponents was 0.5-1 in every different land use types,farmland,grassland and waters show the increasing tendency,while woodland would appear a possible decrease,so some measures should be taken to prevent woodland degradation.