摘要
依据光谱和植物生理参数再联合PROSAIL模型模拟光谱曲线对应的冠层含水量(E)敏感指数,与实际光谱曲线的E敏感光谱指数对比,PROSAIL模型模拟光谱曲线精度较高,相关系数R2>0.8.对光谱的E敏感波段进行单因素和整体敏感性分析,E敏感波段分别为1240、1450、1650 nm.通过水分指数、水分压力指数(MSI)、归一化差异红外指数(NDII)和结合E敏感波段构建的4个广义归一化差异水指数(NDWI)对紫花苜蓿E进行反演,7个指数均具有较好的反演效果,R2>0.8,均方根误差为0.0010~0.0019 g/cm2,其中传统水分敏感光谱指数的E-MSI、E-NDII、E-NDWI((860,1240))和基于广义光谱指数的E-NDWI((1240,1650))的反演效果最佳.
According to the spectral and plant physiological parameters,combined with the PROSAIL model,the equivalent water thickness canopy(E)sensitivity index corresponding to the spectral curve was simulated,and it was compared with the E sensitivity spectral index of the actual spectral curve:the PROSAIL model had high precision in simulating spectral curve,and R~2>0.8.The single factor and overall sensitivity analysis of the E sensitive band of the spectrum showed that the E sensitive band was1240,1450 and 1650 nm respectively.Through the inversion of alfalfa E by water index,moisture stress index(MSI),normalized difference infrared index(NDII)and four generalized normalized difference water indexes(NDWI)were combined with the E sensitive band:it was concluded that the seven indexes had a good inversion effect,R~2>0.8,and the root mean square error was between 0.0010-0.0019 g/cm~2.Of them,the inversion effect of E-MSI,E-NDII,E-NDWI(860,1240)and E-NDWI(1240,1650)based on generalized spectral index was the best.The E of alfalfa can be retrieved accurately,therefore providing a reference for the evaluation of alfalfa water deficit.
作者
唐源
王小平
鲁聪聪
赵传燕
TANG Yuan;WANG Xiao-ping;LU Cong-cong;ZHAO Chuan-yan(State Key Laboratory of Grassland Agro-ecosystem,College of Pastoral Agriculture Science and Technology,LanzhouUniversity,Lanzhou 730020,China;Lanzhou Institute of Arid Meteorology,China Meteorological Administration,Lanzhou 730020,China;College of Resources and Environment,Gansu Agricultural University,Lanzhou 730070,China)
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2023年第1期55-62,共8页
Journal of Lanzhou University(Natural Sciences)
基金
国家自然科学基金项目(42075120)
甘肃省自然科学基金项目(20JR10RA448)。
