Studies On Variation And Remote Sensing Estimation Of The Main Agricultural Biophysical And Biochemical Parameters Of Winter Wheat Under Different Irrigation-Fertilization Conditions

The subjects of this thesis are to analyze the correlation between each key biophysical and biochemical parameter and another of winter wheat under various irrigation-fertilization conditions, based upon which to set up correlation model, to collect the reflection information of wheat canopy through Hyperspectral Remote Sensing, based upon which to conduct statistical analysis between biophysical and biochemical parameter and reflection spectra, and typical spectral parameters, and finally to set up the remote regression models between various typical spectral parameters and biophysical and biochemical parameters.Under different irrigation-fertilization conditions, we conducted a correlation analysis on soil water content, plant water content, canopy temperature, difference of canopy temperature and atmospheric temperature, and reached below conclusions:1 . Soil water content is in positive correlation with water content of plant2. Soil water content is in negative correlation with canopy temperature3. Water content of plant is in significant positive correlation with the difference of canopy temperature and atmospheric temperature.While conducting analysis on various biophysical parameters, we analyzed the difference of canopy temperature and atmospheric temperature for varieties - Jing 411 and Zhong You 9507 under different nitrogen fertilization conditions and irrigation conditions, and found out:4. Under different nitrogen fertilization, the difference of canopy temperature and atmospheric temperature of Zhong You 9507 is higher than that of Jing 4115. Under different irrigations, the difference of canopy temperature and atmospheric temperature of Zhong You 9507 is lower than that of Jing 411By conducting the analysis on the difference of canopy temperature and atmospheric temperature for wheat, oriental drought-resistance wheat and the hybrid off-springs, we find out there exists certain correlation at different special layers cross canopy. There is significant positive correlation between the upper layer and middle layer, between the upper layer and bottom layer, and between the middle layer and bottom layer. But as the layers lower, the temperature difference decreases.We also measured and analyzed the canopy humidity under different irrigation-fertilization conditions and found out that the canopy humidity increases with significant gradient as the special layer cross canopy lowers.Through Hyperspectral Remote Sensing technology to monitors the growth, we focused on the statistical correlation analysis between biophysical and biochemical parameters and reflectance spectra, between biophysical and biochemical parameters and typical spectral parameters, to detect out sensitivity bands or the optimal typical spectral parameters, and to set up biophysical and biochemical parameter statistical correlation model based on spectral parameters.By conducting statistical correlation analysis between 46 typical spectral parameters and watercontent of the plant, between 46 typical spectral parameters and leaf chlorophyll parameter, between 46 typical spectral parameters and leaf nitrogen content, between 46 typical spectral parameters and stem nitrogen, between 46 typical spectral parameters and ear nitrogen content, between 46 typical spectral parameters and LAI on such 10 varieties as Jing411 ,Zhong Yu9507,Jing Wangl0,TaiT15,Lunkang6, CA, CA9554, CA9722, CA9901 , H3276, we find out the sensitive spectral parameters and use it to set up the remote sensing regression model for biophysical and biochemical parameters based on canopy spectral parameters,By conducting statistical correlation analysis individually for 46 spectral parameters under 60 thousand pieces, 120 thousands pieces, 240 thousands pieces density, we found out the sensitive spectral parameters with different biophysical and biochemical parameters.Based on the correlation analysis between various biophysical and biochemical parameters and spectral parameters under different density, for differe...