武汉都市圈植被NDVI变化特征及其对气候变化的响应

Characteristics of NDVI vegetation changes and its response to climate change in Wuhan metropolitan area

本文以SPOT/VEGETATION NDVI卫星遥感数据为基础,结合气温数据、降水数据对武汉都市圈归一化植被指数(NDVI)的时空分布特征和变化趋势进行分析,采用相关分析方法对1998-2015年武汉都市圈植被NDVI与气候因子的相关性进行分析。结果表明:在空间分布上,年平均植被NDVI整体呈现出四周高中间低的空间分布格局,武汉都市圈植被生长状况较好;在时间尺度上,NDVI以0.006/a的速率显著增加;年平均气温表现为波动下降趋势,下降速率为0.02℃/10a,年平均降水量以68.6 mm/10a的速率呈下降趋势,但两者的变化趋势都没通过显著性检验;年际植被NDVI与气温、降水量显著相关的面积比为12.9%和13.2%,其中与气温显著正相关的面积大于负相关面积,而与降水显著负相关的面积大于正相关面积。因此,武汉都市圈植被整体呈稳定恢复趋势,气候变化促进了植被NDVI增加。

This paper analyzed the temporal and spatial distribution characteristics and changing trends of Normalized Difference Vegetation Index(NDVI)in Wuhan metropolitan area based on SPOT VEGETATION NDVI satellite remote sensing data,combined with temperature and precipitation data.The correlation analysis method was used to analyze the correlation between vegetation NDVI and climatic factors in Wuhan metropolitan area during 1998-2015.The results show that:the average vegetation NDVI as a whole presents a spatial distribution pattern of high,middle and low all around;On the time scale,the annual average NDVI increased significantly at a rate of 0.006/a;the annual average temperature showed a fluctuating downward trend,with a decreasing rate of 0.02℃/10a,while the annual average precipitation showed a downward trend at a rate of 68.6mm/10a;the area ratios of vegetation NDVI significantly correlated with temperature and precipitation were 12.9%and 13.2%.The area of vegetation NDVI significantly positively correlated with temperature was larger than the negative correlation area,while the area significantly negatively correlated with precipitation was greater than positive correlation area.Therefore,the overall vegetation of Wuhan urban circle showed a stable recovery trend,and climate change promoted the increase of vegetation NDVI.