华北地区植被NDVI与不同气候指标的相关分析

Correlation Between NDVI and Different Climate Indices in North China

对1982—2006年华北地区归一化植被指数(NDVI)与不同气候指标(年平均气温、年降水量、干燥度指数、生物热量指数和生物干湿度指数)的相关性进行了分析。结果表明,1982—2006年华北地区植被NDVI总体呈现上升趋势,其中农田和灌丛的植被NDVI上升趋势最明显;1982—2006年华北地区年平均气温和生物热量指数呈显著增加趋势,年降水量、干燥度指数和生物干湿度指数呈减少趋势;整体上华北地区植被NDVI年变化与当年的干燥度指数呈极显著负相关,与上一年的年平均气温呈显著正相关关系,其中草地植被NDVI与年均气温、年降水量呈现显著正相关,与干燥度指数呈极显著负相关,农田和灌丛植被NDVI与年均气温显著正相关。此外,华北地区植被NDVI与不同气候指标的相关性存在明显的空间差异。

This paper analyzed the correlations between normalized differential vegetation index（NDVI） and different climate indices（annual mean temperature, annual precipitation, aridity index, biological heat index and biological humidity index） in North China from 1982 to 2006. Results showed that temporal change of NDVI presented an overall upward trend, especially in farmland and bush land. Mean annual temperature and biological heat index increased significantly, while annual precipitation, aridity index and biological humidity index decreased. Overall, the NDVI was significantly negatively correlated with aridity index in corresponding period and positively correlated with temperature in previous period. The NDVI for grassland had a significantly positive correlation with mean annual temperature and precipitation and a most significantly negative correlation with aridity index. The NDVI for farmland and bush land was significantly positively correlated with mean annual temperature. In addition, there were significant spatial differences in the correlation between NDVI and climatic indices in North China.