基于Prospect,Liberty和Geosail模型的森林叶面积指数的反演

Leaf Area Index Retrieval Based on Prospect,Liberty and Geosail Models

针对传统的统计模型方法反演叶面积指数(LAI)具有不稳定、区域不统一性的缺点,本研究从物理机制角度出发,以Prospect,Liberty和Geosail模型为基础,建立查找表从TM影像上反演LAI,并与TRAC实测的LAI比较。结果表明:基于机制模型与查找表的方法反演的LAI与实测的LAI有较好的一致性,实测精度达到83.7%。

Leaf area index（LAI） is a key forest structural parameter which plays an important role in controlling the exchange and cycle process of maters and energy in land ecosystem.Because of the disadvantages of unstable and various statistical models for LAI retrieval,this paper presents a new method of LAI retrieval from TM images based on the Geosail bidirectional canopy reflectance model coupled with the Prospect and Liberty leaf optical properties model and look-up-table.Compared with the LAI measurements by TRAC（tracing radiation and architecture of canopies）,the results show that LAI estimated from phyisical models and look-up-table and LAI measurements are in good agreement,with precision is 83.7%.