基于MODIS NDVI和NPP数据,选取包括气温和降水量的宝鸡11个气象站点的气候指标,分析了宝鸡地区2001～2013年植被覆盖规律的时空变化.运用趋势分析方法探讨了13 a宝鸡地区年均NDVI空间变化趋势;采用相关分析法进一步对宝鸡地区年均NDVI、NPP与年均温和年降水量的相互关系进行了分析.结果表明:2001～2013年宝鸡地区年均NDVI以0.032/10 a的速度上升,较快于三北防护林工程区1982～2006年植被覆盖的增速(0.007/10 a),且2001～2002、2003～2004年两个年份段为年均NDVI值的两次高恢复期;植被覆盖以轻度改善为主,基本不变和中度改善次之,严重退化和中度退化最弱.除个别地区外,植被覆盖恢复状况整体上呈稳中上升的较好趋势;宝鸡全区植被覆盖与气温和降水量相关性均较好,大部分地区呈现正相关;退耕后10 a,NDVI与NPP具有同步增减的变化趋势.%Based on MODIS NDVI and NPP data, according to the climatic indexes (air temperature, rainfall, etc.) of 11 meteorological stations in Baoji area, we analyzed the temporal and spatial changes in vegetation cover in Baoji area from 2001 to 2013. The spatial variation trend of annual average NDVI in Baoji area during 2001～2013 was explored by using trend analysis method. The correlation analysis method was used to further analyze the correlations between annual average NDVI, NPP and an-nual average air temperature, annual rainfall in this area. The results showed that:from 2001 to 2013, the annual average NDVI in Baoji area increased at the rate of 0.032/10 a, and its increasing rate was higher than that (0.007/10 a) of vegetation cover in Sanbei Shelterbelt Project Area from 1982 to 2006; there were two high-recovery periods of annual average NDVI in Baoji area from 2001 to 2002 and from 2003 to 2004; the vegetation cover in this area was mainly mildly improved, and was little seriously or moderately degenerated; except for individual regions, the restoration of vegetation cover had a better tendency of steadily rising as a whole; there were better correlations between vegetation cover and air temperature, rainfall in Baoji area, and these correla-tions were positive in most regions; ten years after returning farmland to woodland, NDVI and NPP had the same change trend.
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