植被指数方法估算冬小麦冠层叶绿素含量的角度效应研究  

Angle Effect Analysis on Estimating Canopy Chlorophyll Content of Winter Wheat by Vegetation Index Methods

作　　者：何宇航 周贤锋 张竞成[1] 张垚 陈冬梅 吴开华[1] 黄文江 孔维平 徐俊锋[4] HE Yu-hang;ZHOU Xian-feng;ZHANG Jing-cheng;ZHANG Yao;CHEN Dong-mei;WU Kai-hua;HUANG Wen-jiang;KONG Wei-ping;XU Jun-feng(School of Artificial Intelligence,Hangzhou Dianzi University,Hangzhou 310018;Key Laboratory of Digital Earth Science,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094;Key Laboratory of Quantitative Remote Sensing Information Technology,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094;Institute of Remote Sensing and Earth Science,Hangzhou Normal University,Hangzhou 310018,China)

机构地区：[1]杭州电子科技大学人工智能学院,浙江杭州310018 [2]中国科学院空天信息创新研究院,数字地球重点实验室,北京100094 [3]中国科学院空天信息创新研究院,定量遥感信息技术重点实验室,北京100094 [4]杭州师范大学遥感与地球科学研究院,浙江杭州310018

出　　处：《地理与地理信息科学》2021年第4期28-36,共9页Geography and Geo-Information Science

基　　金：国家自然科学基金项目(41901268、41901369);浙江省自然科学基金项目(LQ19D010009、LY16D010007);浙江省公益技术应用农村农业项目(LGN19F030001)。

摘　　要：叶绿素是表征作物长势状况、光合作用能力及生理状况的重要指标,其含量变化对于分析作物生理生化过程以及指导作物精准管理具有重要意义。该文结合辐射传输模型模拟数据和实测多角度遥感数据研究不同叶倾角株型冬小麦叶绿素含量反演的角度效应,即观测天顶角和太阳天顶角变化对植被指数方法估算冬小麦冠层叶绿素含量精度的影响。结果表明:模拟与实测多角度数据的角度效应影响植被指数与冠层叶绿素含量的相关性,实测多角度数据观测天顶角变化对植被指数与冠层叶绿素含量相关性的影响显著高于太阳天顶角以及平均叶倾角变化特征的影响。其中,实测多角度数据下,红边归一化植被指数(ND705)在后向10°和20°观测天顶角下估算冠层叶绿素含量精度最高(R^(2)=0.71,RMSE=49.95μg/cm^(2),RRMSE=22%);角度不敏感植被指数(AIVI)垂直观测下估算冠层叶绿素含量精度最高(R^(2)=0.72,RMSE=49.08μg/cm^(2),RRMSE=21%);观测天顶角小于30°时,红边植被指数估算冠层叶绿素含量精度受角度效应影响较小。Chlorophyll is an important index to characterize nutritional status,photosynthetic capacity and physiological status of crops,changes of its content are crucial for physiological and biochemical process analysis and precise management guiding of crops.In this paper,synthetic data simulated from radiative transform models and measured data collected from field experiments were used to investigate the influence of angle effect on estimating canopy chlorophyll content of winter wheat,that is the influence of variation of solar zenith angle and viewing zenith angle on estimating canopy chlorophyll content of winter wheat for different plant types and mean leaf angles using vegetation index methods.The study results showed that angle effect of the simulated and measured multi-angle data affected the correlation between vegetation indices and canopy chlorophyll content.The influence of viewing zenith angle on the correlation between vegetation indices and canopy chlorophyll content was significantly higher than that of solar zenith angle and mean leaf angle.Based on measured multi-angle data,ND705 achieved a high accuracy in estimating canopy chlorophyll content from 10°and 20°backscattering viewing angles(R^(2)=0.71,RMSE=49.95μg/cm^(2),RRMSE=22%),while AIVI had the highest accuracy in estimating canopy chlorophyll content from nadir viewing angle(R^(2)=0.72,RMSE=49.08μg/cm^(2),RRMSE=21%).The accuracy of estimating canopy chlorophyll content by red edge vegetation indices was less affected by angle effect when viewing zenith angles were less than 30°.

关 键 词：植被指数 冠层叶绿素含量 多角度遥感 辐射传输模型 角度效应 

分 类 号：S127[农业科学—农业基础科学] S512.11