利用统计学相关方法对嘉陵江流域1982—2006年NDVI变化规律及其与降雨、气温、日照时数的耦合关系进行研究。结果表明:1982—2006年流域内年均NDVI值呈增长趋势,其中春季增长趋势最明显;年均NDVI值与气温的相关关系最好;在各个季节,流域季平均NDVI值随降雨、气温变化都存在一定的滞后现象,尤其在植被生长较为旺盛的春、夏、秋季。春季,流域NDVI值和上季度温度以及本季度日照时数关系较为显著;夏季,流域NDVI值受本季度和上季度各个气象因子影响较大;秋季,流域NDVI值和日照时数相关关系较好,同时受上季度气温影响较大。
The variation of the normalized difference vegetation index(NDVI) and its relationship with precipitation,air temperature,and sunshine duration in the Jialing River Basin during the period from 1982 to 2006 were studied using statistical methods.The results show that the annual average NDVI had an increasing trend during the study period,especially in the spring,and it was highly correlated with temperature.In all seasons,there was a lag in the change of the seasonal average NDVI when the air temperature and precipitation changed in the basin,especially in the vegetation growth seasons: spring,summer,and autumn.In the spring,the relationships between the average NDVI and the sunshine duration in the present quarter and the air temperature in the previous quarter were more significant.During the summer,the average NDVI was significantly influenced by meteorological factors of both the present quarter and the previous quarter.During the autumn,the average NDVI was significantly correlated with sunshine duration and was greatly influenced by the air temperature in the previous quarter.