大兴安岭地区森林叶片反射率的反演

Inversion of Forest Foliage Reflectance in Daxing'anling Region

叶片反射率作为一个重要的植被参数对森林的研究有着重要的意义,而遥感影像所获得是像元信息也就是植被冠层反射率。为了的得到叶片反射率,本文利用地表反射率8天合成产品(MOD09A1)、叶面积指数产品(MOD15A2)和地表覆盖类型产品(MCD12Q1),结合四尺度模型与PROSPECT模型模拟冠层反射率所建立的冠层反射率和叶片反射率之间的查找表,反演了2015年8月份大兴安岭地区的叶片反射率,实现从冠层反射率到叶片反射率的尺度转换,并使用SVC-1024i实地采集的叶片反射率信息做精度检验。研究结果表明实地测量数据与查找表反演叶片反射率在红色和近红外波段具有良好的相关性(R^2为0.789和0.796),表明了利用四尺度模型建立查找表反演叶片反射率具有可行性。

As one of the most important vegetation parameters, foliage reflectance plays a significant role in forest research. The pixel information extracted from remote sensing images is the canopy reflectance. In order to obtain the foliage reflectance, a lookup table between canopy reflectance and foliage reflectance, which is built from simulating canopy reflectance by MODIS Surface Reflec-tance products （MOD09A1） , Leaf Area Index products （MOD15A2） , land cover types （MCD12Q1） combined with four - scale model and PROSOECT model, is used to invert the foliage reflectance in Daxing’anling region in August, 2015. A scale conversion from canopy reflectance to foliage reflectance is accomplished. The foliage reflectance data acquired by SVC - 1024i device in the for-est is used to do accuracy test. Results show that the field data and foliage reflectance inverted by look - up table have good correlation in Red and Near - infrared bands （ R2 is 0. 789 and 0. 796 ） , which means using look - up table based on four - scale model to invert foliage reflectance is feasible.