基于高光谱指数的棉花冠层等效水厚度估算

马岩川,刘浩,陈智芳,张凯,余轩,王景雷,孙景生

Canopy Equivalent Water Thickness Estimation of Cotton Based on Hyperspectral Index

YanChuan MA,Hao LIU,ZhiFang CHEN,Kai ZHANG,Xuan YU,JingLei WANG,JingSheng SUN

表3 CEWT与已发表的植被指数及本文提出光谱指数相关性比较

Table 3 Correlation analysis of CEWT with published spectral index and spectral index proposed in this paper

光谱指数 Spectral index 生育期 Growth stage 建模 Calibration 检验 Validation 回归方程 Regression equation R2 SE n R2 RRMSE n NDWI1240(R860,R1240)[16] 全生育期Full growth period y=-2.4144x+0.2131 0.348 0.141 104 0.234 0.346 52 WI(R970,R900)[30] 全生育期Full growth period y=-4.0076x+4.1002 0.408 0.134 104 0.272 0.338 52 SRWI(R858,1240)[42] 全生育期Full growth period y=1.0643x-0.8479 0.365 0.139 104 0.245 0.343 52 NDII(R850,R1650)[43] 全生育期Full growth period y=-0.4851x+0.2487 0.150 0.161 104 0.038 0.402 52 NDWI1200(R860,R1200)[44] 全生育期Full growth period y=-2.3652x+0.1715 0.338 0.142 104 0.259 0.341 52 NDWI1640(R860,R1640)[45] 全生育期Full growth period y=-1.3136x-0.0362 0.448 0.129 104 0.439 0.298 52 MSI(R1600,R820)[46] 全生育期Full growth period y=-1.0884x+0.9157 0.418 0.133 104 0.406 0.307 52 RSI(1134,1533) 全生育期Full growth period y=0.2639x-0.3392 0.700 0.095 104 0.724 0.210 52 RSIb(1130,1996) 蕾期Bud stage y=0.0316x-0.049 0.767 0.049 42 0.726 0.144 18 RSIa(904,1952) 花铃期Flowering and bolls stage y=0.0573x +0.0849 0.870 0.060 62 0.785 0.245 34 (R1135-5R1494)/R2003 全生育期Full growth period y = 0.0932x+0.6188 0.788 0.080 104 0.801 0.180 52 (R1135-5R1494)/R2003 蕾期Bud stage y=0.0893x+0.5864 0.688 0.060 42 0.761 0.229 18 (R1135-5R1494)/R2003 花铃期Flowering and bolls stage y=0.0853x+0.6204 0.712 0.091 62 0.740 0.162 34