森林多尺度结构空间分布对冠层反射率的影响研究

Spatial distributions of forest structures at multiple scales directly affect the process of radiative transfer in forest canopies and canopy reflectance detected by remote sensors. Geometric-optical (GO) models are very suitable for structural parameter retrieval for discrete vegetation canopies because of their emphasis on vegetation structures and their interaction with radiative transfer processes within the canopy. As current needs of remote sensing applications as well as some deficiencies of existing researches of forest GO models on structures spatial distributions, firstly, forest structures will be abstracted and modeled at stand, compartment, and branch scales, respectively. Secondly, a new five-scale GO model, which will be expressed more accurately and applied more widely, will be built based on the five-scale GO model in this project. Thirdly, the scale effects of forest muti-scale structures distributions and their influence on canopy reflectance will be presented, respectively. The new model to be developed and validated in this project could lead to a new generation of GO models applicable for multiple scales of forests. It will definitely provide an effective tool to improve the retrieval of the forest parameters on multiple scales of forests using remote sensing images.

森林多尺度结构的空间分布直接影响了光子在冠层内的传递过程以及遥感探测到的冠层反射率。几何光学模型从物理机制上解释了离散冠层结构特征与辐射传递过程的关系。本项目拟针对目前遥感应用的实际需要和现有森林几何光学模型在结构空间分布方面的研究不足，首先分别在林分、小班和枝尺度对森林结构的空间分布进行抽象和建模；其次基于五尺度几何光学模型，构建一个表达更准确、应用性更强的新五尺度几何光学模型，并对新模型进行对比和验证；最后，分析森林多尺度结构空间分布的尺度效应及其对冠层反射率的影响。所建立的新模型将为发展适用于森林多尺度的新一代几何光学模型奠定基础，为提高森林多尺度参数遥感反演的可靠性提供有效工具。

森林多尺度结构的空间分布直接影响了光子在冠层内的传递过程以及遥感探测到的冠层反射率。几何光学模型从物理机制上解释了离散冠层结构特征与辐射传递过程的关系。本项目针对目前遥感应用的实际需要和现有森林几何光学模型在结构空间分布上存在的不足，首先分别在林分、树冠尺度和叶片尺度对森林结构的空间分布进行抽象和建模；其次基于五尺度几何光学模型，构建一个表达更准确、应用性更强的新五尺度几何光学模型，并对新模型进行对比和验证；最后，分析森林多尺度结构的空间分布对冠层间隙率、聚集度指数和冠层反射率的影响。