项目名称: 基于MODIS BRDF产品的叶片聚集度系数遥感反演与验证研究
项目编号: No.41271354
项目类型: 面上项目
立项/批准年度: 2013
项目学科: 天文学、地球科学
项目作者: 朱高龙
作者单位: 闽江学院
项目金额: 75万元
中文摘要: 植被叶片聚集度系数表征了冠层叶片的空间分布集聚特征,是一个与叶面积指数具有同等重要意义的植被结构参数。但是由于遥感资料的限制,目前基于多角度遥感的聚集度系数反演理论与技术还处于探索阶段。本项目基于4尺度几何光学模型和改进型核驱动BRDF模型,发展了利用MODIS BRDF模型参数产品提取500 m 分辨率的叶片聚集度系数的理论与方法,生产了我国2000-2012年聚集度系数产品,并分析其时空变化特征。利用地面观测数据,经过尺度转换,对MODIS聚集度系数产品的精度进行验证,并发展利用聚集度系数改正低分辨率LAI空间尺度效应的方法。该研究成果对于提高LAI产品质量和生态系统模型结果的可靠性具有重要的科学意义。
中文关键词: 聚集度系数;叶面积指数;多角度遥感;精度验证;核驱动BRDF模型
英文摘要: As an additional vegetation structure parameter of comparable importance to leaf area index (LAI), the foliage clumping index quantifies the deviation of the leaf spatial distribution from the random case. However, due to the lack of multi-angular remote sensing data, few efforts have been made to inverse this parameter. This project is focused on a new inversion algorithm of the 500 m resolution clumping index from MODIS BRDF data. By the 4-Scale geometrical model and the modified Ross-Li kernel-driven BRDF model, the clumping index over China at 500 m resolution is retrieved every 8 days during the period from 2000 to 2012, and the spatial and temporal variations of the retrieved clumping index in China are also analyzed. The ground measurements are scaled to 500 m resolution to validate the MODIS clumping index. Finally, the clumping index is first used to compensate the scaling effect of LAI with coarse spatial resolution. These results will improve LAI product, and can be supplied to users for various land surface studies.
英文关键词: clumping index;leaf area index;multi-angular remote sensing;accuracy validation;kernel-driven BRDF model