植被指数与叶面积指数关系研究及定量化分析

基于ETM 原始图像、相应的视反射率图像和大气校正后的地面反射率图像，分别计算了贵州黎平县北部杉木林区相应的归一化植被指数。研究发现，基于视反射率图像计算出的归一化植被指数为相应原始影像的3～4倍，基于大气校正后的地面反射率图像计算出的归一化植被指数是相应原始图像的4～5倍。研究结果表明，归一化植被指数与相应地面实测的叶面积指数有着较好的线性相关关系，并且传感器影响去除、大气校正等技术手段将逐步提高归一化植被指数与实测LAI的相关系数。由此说明，在实际工作中，遥感信息定量化是极其必要的。

Research and Quantitative Analysis of the Correlation Between Vegetation Index and Leaf Area Index

Basing on the DN image, apparent reflectance image and atmospheric corrected reflectance image, the NDVI of fir forest from ETM + image over the north of Liping County in Guizhou Province we are calculated. It has been found that the NDVI based on apparent reflectance is 3 - 4 times larger than that based on the DN and the NDVI based on atmospheric corrected reflectance is 4 -5times larger than that based on the apparent reflectance. The research results have also showed that there is a good positive linear correlation between NDVI and ground truth LAI and the removal of influence of remote sensing sensor and atmospheric correction can increase the correlation coefficient. So quantitative analysis of remote sensing information is necessary.