Research On Remote Sensing Monitoring Technology Of Water Eutrophication Based On Hyperspectral Data

China is a country with shortage of water resources and drought in many areas throughout the year.Therefore,the eutrophication of freshwater resources in China needs to be taken seriously.In order to study the water eutrophication status of Daqing area,the water quality of Daqing Reservoir and Hongqipao Reservoir was monitored by remote sensing based on the hyperspectral MODIS data received by MODIS sensors on Terra satellite.Chlorophyll a was selected as the water quality parameter for the study.Select Daqing Reservoir and Hongqipao Reservoir as the research samples in the area of Daqing City,select ten sampling points in the Daqing Reservoir and study and analyze the water quality parameters of these ten sampling points,and obtain the total phosphorus in the water body through the analysis of laboratory water quality parameters,Total nitrogen,chlorophyll a potassium permanganate index and other indicators.Correlation analysis of its water quality indicators showed that the concentration of chlorophyll a had the highest correlation with total phosphorus.Based on the multiple linear regression model,the concentration of chlorophyll a was predicted.The results showed that the model could effectively predict the content of chlorophyll a in water.The band analysis obtained from the interpretation of remote sensing images,using the ratio model to establish an inversion model of the water quality parameters of Daqing Reservoir,and using the water quality parameters of the Hongqipao Reservoir in the same area to verify and analyze the model,and finally based on the Carlson eutrophication index method The eutrophication degree of the entire Daqing Reservoir is evaluated and analyzed.The results show that the model has the highest correlation at the ratio of Band 2to Band 3,R2 = 0.805,and at the same time,under the verification of Hongqipao Reservoir data,it is found that the maximum relative error of the chlorophyll a concentration value retrieved by the model is 21.74%,The minimum relative error is0.35%,and the average relative error is 4.53%,which is within the allowable range oferror.From the distribution map of the water eutrophication status of the Daqing Reservoir with the TSI value,it can be seen that the water eutrophication status of the Daqing Reservoir is mostly light eutrophication,and a small part is moderate eutrophication.Light eutrophication probably accounts for the whole 80% of the reservoir,and moderate eutrophication accounts for 20% of the entire reservoir.From this,we can find that the water body of Daqing Reservoir is more eutrophic and the water quality problem is serious.People should pay attention to it.