Retrieval Of Phycocyanin Concentrations Based On Water Reflectance Spectra Classification In Taihu Lake

The phycocyanin pigment is a symbol of cyanobacteria,and it has important significance for the monitoring and early warning of cyanobacteria bloom by using remote sensing inversion.The temporal and spatial difference of the optical properties of the water body in Taihu is relatively large,and the application of the remote sensing inversion method to the traditional methods of the remote sensing of the algae in Taihu lake is limited.In this paper,we use the method of the first classification and then to obtain the data of the measured spectra and water quality parameters in Taihu.Based on the water surface reflectance spectra,the model of the concentration of Taihu's blue protein concentration is obtained.The K mean clustering method is used to realize the spectral classification.Then the model is established by using each kind of training sample data.Finally,the accuracy of the model is evaluated by using the test data of each class.In order to contrast,the traditional method is used to inverse modeling and precision evaluation.Test results show that the traditional modeling method based on classification does not get the RMSE=14.14 ug/L,a=59.1%,the inversion results and the measured data,the correlation coefficient is 0.46;modeling method based on spectral classification to obtain the RMSE=8.47ug/L,?=31.3%,and inversion results and the measured data,the correlation coefficient was 0.87.According to this method,a model for the estimation of the pigment concentration in the MERIS data classification is established.After inspection,in order to contrast,the traditional method is used to inverse modeling and precision evaluation.Test results show that the traditional modeling method based on classification does not get the RMSE=11.14 ug/L,?=64.2%,the inversion results and the measured data,the correlation coefficient is 0.57;modeling method based on spectral classification to obtain the RMSE=8.87ug/L,?=38.7%,inversion results and the measured data,the correlation coefficient of 0.85.Therefore,the method of the spectral classification based on the method of algal protein inversion can effectively improve the inversion precision,and can provide a reference for the inversion of the concentration of the algae blue protein in other waters.