利用遥感监测浙江省酸雨对植被的影响

The Effect of Acid Rain on Vegetation by Using Remote Sensing Monitoring in Zhejiang Province

为了研究酸雨对浙江地区不同类型植被的影响,利用1999～2004年间归一化植被指数(Normalized Difference Vegetation Index,NDVI)数据集及相对应的酸雨监测数据,结合浙江省植被空间分布图,计算了不同酸雨梯度分布区域内降水pH值与植被NDVI的相关系数。研究结果表明:浙江省酸雨对植被的生长状况有显著影响,在城市附近尤其明显。通过不同酸雨梯度的NDVI年均值比较,pH值越低区域,NDVI值越低,植被受害越严重。不同酸雨梯度pH值与NDVI值随季节变化呈正相关,并且秋冬两季更显著。建立了马尾松林、杉木林、毛竹林和经济林、阔叶林、疏林地以及灌木林6种植被类型的NDVI与酸雨pH值之间的反演关系,结果具有良好的精度,可用于监测大尺度酸雨对植被的影响。灌木林和阔叶林NDVI值对酸雨的危害反应最敏感,其次是毛竹林和杉木林,而马尾松林和疏林地对酸雨的危害反应相对不十分敏感。浙江省酸雨在杭州、宁波、嵊州、台州、温州以及衢州盆地为中心的地区呈现pH低值区,西南部的龙泉,庆元、云和等县市污染相对较轻。

To understand the effect of acid rain on vegetation in Zhejiang Province, correlation coefficient was calculated by using the Normalized Difference Vegetation Index （NDVI） data from 1999 to 2004 and corresponding acid rain monitoring data combining with the vegetation spatial distribution map of Zbejiang Province. The results showed that acid rain has significant effect on vegetation in Zhejiang Province, especially near city. The NDVI decreases with the decrease of pH value of rain, and the health of vegetation also decline, through the comparison of mean annu- al NDVI in different acid rain acidity. There is a positive correlation between the pH value and seasonal average NDVI especially in autumn and winter in different acid rain acidity. The retrieval relationships with good retrieval accuracy of NDVI and pH value of acid rain have been established to the six vegetation types （ masson pine forests, Chinese fir forests, moso bamboo forests and economic forests, breadleaf forests open forest lands and shrubs） in this study, which could be useful for monitoring the effect of acid rain on vegetation on a large scale. The NDVI of shrub and broadleaf forests is most sensitive to the acid rain, then the moso bamboo forests and Chinese fir forests. And the sensitivity of massen pine forests and open forest lands is low relatively. The regions of low pH value of acid rain are Hangzhon, Ningbo, Sbengzhou, Taizhou, Wenzbeu and Quzhou basins, and air pollution in Longquan, Qingyuan and Yunbe cities is slight relatively.