Suspended solids concentration estimation in Lake Taihu using field spectra and MODIS data
WANG Yanhong1,2, DENG Zhengdong2,*,MA Ronghua31. Institute of meteorology, PLA University of Science and Technology, Nanjing 2111012. Engineering Institute of Engineering Corps, PLA University of Science and Technology, Nanjing 2100073. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008
Taking Lake Taihu as the study area, the field reflectance spectrum was measured, and the in-situ water samples were collected and analyzed in the lab. After analyzed the spectrum features, suspended solids (SS) concentration were estimated by field spectra. Then by the comparison of the bands of MODIS and the correlation between SS and MODIS bands reflectivity, the principal component analysis (PCA) were analyzed. The most practicable band, the first and the second principal component were selected to educe the estimation models. The results show that the peak value near 576nm, the peak height near 808nm, and the first derivative at 841nm have good correlations with SS concentration. Among these, the estimation precisions of the two later are close. The correlation between MODIS band 1 and SS concentration is more corresponding than the other bands. The precisions to estimate SS using the first and the second principal component are also good. Therefore, MODIS data can be used in long term dynamic monitoring of SS concentration in Lake Taihu.