基于叶面积指数的植被覆盖管理措施因子C的遥感定量估算

Quantitative Assessment of Vegetation Cover and Management Factor Based on Leaf Area Index and Remote Sensing

以植被结构因子——叶面积指数(LAI)取代长期以来用于水土保持定量评价的植被覆盖度,通过遥感技术反演植被结构因子LAI,构建研究区LAI与植被覆盖管理措施因子C量化耦合模型,并进行模型精度验证。结果表明:基于LAI模拟的土壤侵蚀模数为455.89t·km-2a-1,属于微度侵蚀,与径流小区野外观测结果一致。本文提出的LAI取代植被覆盖度作为水土保持定量估算与评价指标是可行的。

Vegetation cover is one of the most crucial factors to determine soil erosion. The forest structure is characterized by the LAI （leaf area index） distribution and the roughness of the canopy from a remote sensing point of view. This paper proposed a method to assess vegetation cover and management factor（C）using leaf area index as input factor,establish the LAI retrieval method based on remote sensing,and then to inverse the quantity coupling model for the C factor and LAI. The results show that soil erosion modulus of the runoff plots is 455.89 t·km-2a-1.According to the national classification standard of soil erosion intensities in China,it is micro-erosion.This exactly coincides with the field observations. This means that LAI is a good substitute for vegetation cover in studies on assessing the soil erosion.