Correlation Analysis between Hyperspectral Vegetation Indices and Photosynthetic Parameters of Cotton under Different Water Treatments
GUO Xiao-fei;HUANG Chun-yan;TIAN Chun-yan;LIU Xin-yue;WANG Deng-wei;Key Laboratory of Oasis Eco - agriculture of Xinjiang Production and Construction Corps,College of Agronomy,Shihezi University;
【Objective】To establish a correlation model between cotton hyperspectral data and photosynthetic characteristic parameters in the hope of providing a scientific foundation for effective,rapid,non- destructive diagnose and surveillance of cotton growth process in large area.【Method】Using ASD hyperspectral radiometer and Li- 6400 photosynthetic instrument,the hyperspectral data of the two varieties Xinluzao No.13 and No.33 in key growth stages and photosynthetic parameters were obtained by five water treatments:net photosynthetic rate(Pn) and stomatal conductance(Gs) were calculated using hyperspectral data to obtain the normalized difference vegetation index(NDVI),ratio vegetation index(RVI) and the second modified soil adjusted vegetation index(MSAVI2) of the two cotton cultivars,thus establishing the linear,logarithmic and power function correlation equations of Pn and Gs,respectively.【Result】The results showed that three type function models were of significant and extremely significant correlation,and the R value of the equation of the three models in the two varieties RVI and Pn and Gs was higher,among which,using Xinluzao 33 RVI and Pn,Gs power function equation to estimate the Pn and Gs and carry on correlation analysis of the predicted value of Pn and Gs with the measured value,it was found that R value reached a very significant level(R measured pn = 0.827,RMSE = 1.089,R measured gs- estimation gs = 0.586,RMSE = 0.138,n = 20,P 0.01).The estimation accuracy of the model equation was greater than 80%.【Conclusion】There was a significant correlation between the spectral vegetation indexes and photosynthetic parameters of the two cotton varieties under different water treatments and the correlation model could be used to estimate the Pn and Gs,and real- time monitoring of the growth status of cotton.
【Fund】： 国家自然科学基金项目(31560354);; 人力资源和劳动社会保障部留学回国人员科技活动项目(RSLX201303)~~
【CateGory Index】： S562
【CateGory Index】： S562