以密云半城子为研究区,以TM影像为数据源,基于RS技术,提取归一化植被指数。根据实测真实叶面积指数及结合土地利用信息确定的聚集度系数,计算有效叶面积指数。在此基础上构建NDVI与有效叶面积指数间的回归模型,最后利用John提出的郁闭度估算模型进行郁闭度的估算,并对估算结果进行精度检验。结果表明:NDVI与有效叶面积指数相关性高,可用于有效叶面积指数的估算;采用有效叶面积指数,综合考虑叶倾角进行郁闭度估算精度较高。
With Miyun Banchengzi as research area and TM images as data sources,RS technology was used to extract the normalized difference vegetation index.According to the measured real leaf area index and land utilization information the concentration coefficients are determined and effective leaf area index calculated.The NDVI and effective leaf area index are unary regression analysis.Finally John 2007 canopy density estimation model is used for canopy density estimation,and the estimation results are accuracy test.The results show that the NDVI high correlation with effective leaf area index and can be used in the estimation of effective leaf area index.Using effective leaf area index and comprehensively considering leaf inclination angle the estimation precision of canopy density is high.
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