北京地区春季气溶胶时空分异特征及其对土地利用的响应

Spatial-temporal Differentiation Characteristic of Aerosol and Its Response to Land Utilization in Beijing Area in Spring

基于长时间序列的气溶胶光学厚度(AOD)、归一化植被指数(NDVI)和归一化建筑指数(NDBI)遥感数据,利用Theil-Sen、Mann-Kendall和偏相关分析方法,探讨了2000~2018年北京地区春季AOD的时空分布特征及其对土地利用的响应。结果表明:北京地区春季年均AOD呈条带状分布,且东南高西北低;近20年来,春季AOD变化差异明显,东南部春季AOD显著增加,西北部则以较高速率降低。NDVI大致呈由内向外逐渐增大的圈层结构,且以增长趋势为主;NDBI则呈现西北-东南方向逐渐增加的空间分布特征,且变化趋势与NDVI相反。西部和北部春季AOD与NDVI的相关性以显著负相关为主;东南部春季AOD与NDBI的相关性也以显著负相关为主。

Based on long time series of aerosol optical depth(AOD),normalized difference vegetation index(NDVI)and normalized difference build-up index(NDBI)remote sensing data,using Theil-Sen,Mann-Kendall and partial correlation analysis methods,the spatiotemporal characteristics of spring AOD and its response to land utilization in Beijing were analyzed from 2000 to 2018.The results show that the average annual AOD in Beijing in spring is striped and high in the southeast and low in the northwest;over the past 20 years,there have been significant differences in AOD changes in spring,the AOD in the southeast shows an obvious increasing trend,while the AOD in the northwest decreases at a relatively high rate.NDVI generally presents a circle structure that gradually increases from inside to outside,and the overall trend is increasing;NDBI shows the spatial distribution characteristics of high in the southeast and low in the northwest,and the change trend is opposite to NDVI.The correlation between AOD and NDVI in spring in the west and north is mainly negative;The correlation between AOD and NDBI in spring in southeast China is also significantly negative.