江苏省NDVI时空变化特征及其与气候因子的关系

目的]分析江苏省NDVI时空变化特征,并探讨该地区NDVI与气候因子之间的关系,为合理制订生态环境保护政策和措施服务。方法]运用一元线性回归模型分析NDVI时空变化特征,运用相关性分析法分析NDVI与气候因子之间的关系。结果](1)江苏省NDVI在2001—2010年上升速率为0.005/a。(2)江苏省部分丘陵山区平均NDVI达到0.8以上,江淮平原及黄淮平原平均NDVI大多位于0.7~0.8之间。(3)年际NDVI与相对湿度的相关系数为-0.720,月际NDVI与当月气温的相关系数为0.860;降雨和相对湿度对NDVI的影响存在滞后效应和累积效应,且滞后期均为1个月。结论]江苏省NDVI在2001—2010年呈上升趋势;NDVI平均值空间分布及其变化趋势区域差异明显;NDVI年际变化与相对湿度相关性最高,而气温对月际NDVI变化影响最大。

Spatiotemporal Variation Characteristics and Impact Factors of NDVI in Jiangsu Province

Objective] Studying the spatiotemporal variation characteristics of NDVI in Jiangsu Province and the relationships between climatic factors with NDVI, in order to provide conferences for planing policies and countimeasures for eco-environment protection.Methods] Linear regression trend method was used to analyze the spatiotemporal variation characteristics of NDVI, and correlation analysis method was used to analyze the relationship between climatic factors with NDVI.Results] (1) The rising rate of average annual NDVI in Jiangsu Province from 2001 to 2010 was 0.005/a. (2) The average of NDVI in some hilly area were over 0.8, in Yangtze-Huai Plain and the Huang-Huai Plain, were mostly between 0.7 and 0.8.(3) The correlation between annual NDVI and relative humidity was -0.720, the correlation between monthly NDVI and the air temperature in the same month was 0.860; There existed lagging effect and accumulation effect for the influence of rainfall and relative humidity on NDVI, and the lag phase were both a month.Conclusion] The average annual NDVI in Jiangsu Province had fluctuated uprising tendency from 2001 to 2010. The distribution and the change trend of average NDVI were distinct in different districts. The correlation of relative humidity and NDVI was the highest on the inter annual timescale, and the air temperature had the most important influence on monthly changes of NDVI.