基于高光谱数据的棉花冠层FPAR和LAI的估算研究

 通过非成像高光谱仪和光量子传感器，获取了棉花2品种4水平种植密度冠层关键生育时期的反射光谱数据和光合有效辐射值；利用光谱多元统计分析技术与微分处理，分析表明，反射光谱813 nm（_ρ813）和758 nm（_ρ758）处分别是光合有效辐射截获量（FPAR）和叶面积指数（LAI）的敏感波段。用反射率_ρ813和_ρ758分别与FPAR和LAI建立的线性相关模型方程估测FPAR和LAI，经检验，它们的实测值与估测值之间均呈极显著的线性相关（r_FPAR=0.7199^**，r_LAI=0.6430^**，α=1％，n=70），模型方程的估算精度分别达96.5%、81.7%；而一阶微分光谱数据与FPAR在350 ~2500 nm波段范围相关不显著,与LAI的最大相关发生在734 nm波段处。基于一阶微分光谱_ρ′734与棉花冠层LAI线性相关的模型方程，估测LAI，实测值与估测值之间呈极显著的线性相关（r_LAI=0.6947^**，α=1％，n=70），估算精度为82.4%，与反射光谱758 nm估测LAI的精度接近。结果表明，棉花冠层光谱数据可以对光合有效辐射截获量FPAR和LAI进行实时、无损、动态、定量的估算。

Estimating of Cotton Canopy Fraction of Photosynthetically Active Radiation and Leaf Area Index Based on Hyperspectral Remote Sensing Data

Utilizing a quantum sensor and non-imaging hyperspectral spectrometer,2 cotton cultivars 4 level densities planting,in north Xinjiang,multi-temporal canopy hyperspectral data and photosynthetically active radiation data at cotton key growing stages were reoorded,and multivariate regression analysis method was used to analyze the correlated relationship between reflectance and cotton canopy FPAR,LAI,respectively.The results showed that the maximum correlation coefficients between hyperspectral data and FPAR,...