| The research scope of this study is Zhangwu County of Liaoning Province,and the remote sensing satellite images of Landsat 8 OLI which in April and June 2016 are pretreated by ENVI software.At the same time,we need to obtain the corresponding measured data of soil moisture content.The study selected the temperature vegetation index method and the perpendicular drought index as an indicator of drought monitoring,the indicators were fitted with soil moisture content and have a significance analysis by using SPSS software,and it is finally got a better drought monitoring model to ZhangWu regional.The main concent and conclusions of this study were as follows:1.Comparing the significant correlation and relationship between the temperature vegetation index and soil moisture content.The results indicated that the fitting effect of temperature vegetation drought index and different depth soil moisture content is poorer,with 30cm soil moisture content of the fitting effect is relatively good,the multiple correlation coefficient is 0.3837;The SPSS software is used to analyze the significance of the two indicating that the soil moisture content of 10cm and 20cm was significantly correlated with TVDI at the level of 0.05,and the soil moisture content of 30cm was significantly correlated with TVDI at the level of 0.01.2.Based on the construction method of drought monitoring model of perpendicular drought index,the fitting results of the PDI inversion data and soil moisture show that the depth of 20cm soil moisture content had the best fitting effect which the correlation coefficient was 0.5555,and the soil moisture of 10cm and 30cm depth fitting effect is relatively poor.Significant results show that soil moisture content of the soil depth in 10cm and 20cm and perpendicular drought index were significant at 0.01 level,the soil moisture of depth in 30cm and perpendicular drought index in the 0.05 level was significantly correlated.3.According to the correlation and significance analysis of the two models,it is found that the fitting results of vertical drought index and soil water content are better than that of soil moisture content and TVDI.Therefore,the drought monitoring model based on vertical vegetation index method is more suitable for drought monitoring in Zhangwu area.4.The method of drought monitoring model based on perpendicular drought index is verified by the satellite map in April 2016.And the soil water content in different depth are analysised between soil moisture inversion value inversion and the measured soil moisture.The results show that the depth of 10cm and the rate of 20cm soil water content are higher than the inversion results for the depth of 30cm 0.1041 and 0.1064.And the soil moisture content of 30cm is the worst,and the correlation coefficient is 0.4945;the multiple correlation coefficient of inversion and measured soil moisture content of 10cm is 0.5986;and the multiple correlation coefficient of inversion and measured soil water content at depth of 20cm is 0.6009.Through the analysis of the accuracy and relative error,the inversion effect of 10cm and 20cm is the best,the average value of 10cm inversion accuracy is 91.25%,and the average value of 20cm inversion accuracy is 88.53%,which is 6.96%and 4.24%higher than the average value of 30cm inversion accuracy.The relative error of 10cm and 20cm in the relative error analysis is 8.9%and 5.34%lower than the relative error of 30cm.The relative error value of 30cm is larger and the value is 18.49%.In drought monitoring,the drought monitoring effect is better in the depth of 20cm and less than 20cm by remote sensing and monitoring model of perpendicular drought index. |
PDF Full Text Request