阴山北麓农牧交错带植被变化及其对气候变化的响应

利用1982—2003年8kmNASA/GIMMS半月合成的植被指数(NDVI)数据和同期气候数据,分析了阴山北麓地区农牧交错带的NDVI年平均值、年累积值距平的动态变化以及NDVI年平均值与年平均温度和年降水的时间序列相关关系。结果表明:1982—2003年NDVI年平均值呈现逐渐增高趋势,1990年以后的NDVI年平均值明显高于以前;NDVI在空间变化上表现为牧业区<农牧区<农业区,说明农业区NDVI受气候的影响程度较牧业区和农牧区弱;研究区温度对植被指数的影响没有明显的规律性,但降水与植被指数呈正相关,降水的多寡决定了植被的生长状况。

Dynamic changes of vegetation in agriculture-animal husbandry ecotone on north foot of Yiushan Mountain with relation to climate change

By using the 8 km NASA/GIMMS half-monthly composite NDVI data and climate data in 1982-2003, this paper studied the dynamic changes of the annual mean value and accumulation anomaly of NDVI on the north foot of Yinshan Mountain, as well as the time series relationships of annual mean NDVI with annual mean temperature and annual precipitation. The results indicated that the annual mean NDVI in 1982-2003 had an increasing trend, and the mean value after 1990 was obviously higher than ever before. The spatial change pattern of NDVI followed the sequence of animal husbandry area < agriculture-animal husbandry area < agricultural area. There was no clear relationship between NDVI and temperature, but a positive correlation was observed between NDVI and precipitation, suggesting that the vegetation growth in the study area was mainly depended on the amount of precipitation.