Correlation between Vegetation Change and Climatic Factors of Xi'an
Based on the analysis of the monthly,quarterly and yearly vegetation NDVI (Normalized Difference Vegetation Index) sequences from December 2002 to November 2012 of Xi'an and the synchronous observation data from seven national weather stations in the city,the characteristics of the NDVI changes and the correlation of the changes with climatic factors were summarized.The results show that in the past 10 years the NDVI of the city has shown an overall upward trend,the annual average NDVI fluctuates between 0.237 8～0.252 5 and in spring the NDVI has the biggest increment of 0.004/a;in the past 10 years the annual precipitation of the city has showed a decreasing trend and the rainy periods are mainly in summer and autumn;the annual NDVI has a good correlation with the synchronous average temperature and the precipitation of the previous year;the NDVI of each season has a good correlation with its average temperature and the precipitation of the previous quarter;vegetation change is about one month behind the rainfall of the city,and human factors has an important effect in vegetation change.
NETL
NSTL
万方数据
维普
