Assessments of trophic state in lakes and reservoirs of Wuhan using Sentinel-2 satellite data

European Journal of Remote Sensing

Baoyin He¹  Qi Feng¹  Fei Xiao¹  Yadong Zhou¹  Congju Fu²  Hui Liu²  Mariano Bresciani³  Claudia Giardino³  Xinmeng Zhou⁴  Shengwen Liang⁴ 

[1] Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, Chin;Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, Chin;University of Chinese Academy of Sciences, Beijing, Chin;Institute for Electromagnetic Sensing of the Environment, National Research Council of Italy, Milan, Ital;Wuhan Environmental Monitoring Center, Wuhan, Chin;

关键词: Sentinel-2;    wuhan;    forel-Ule index (FUI);    trophic level index (TLI);   

DOI  :  10.1080/22797254.2021.1960201

来源: Taylor & Francis

【 摘 要 】

With the rapid development of economy, many lakes in Wuhan have been polluted to different degrees and suffer from eutrophication. The main objective of this study was to conduct the monthly trophic state assessments of waters in Wuhan from March 2019 to June 2020 using 111 Sentinel-2 images. The Forel-Ule index (FUI) and empirical Gaussian process regression (GPR) were, respectively, applied to obtain monthly area percentage (AP) of waters with each trophic state. Both FUI-derived and empirical GPR-retrieved results showed that majority of water bodies (>90%) in Wuhan were in mesotrophic and eutrophic states. The GPR-retrieved results based on FUI-derived water types were more reliable than the retrieval without classification, which reduced RMSE of trophic-level index (TLI) from 9.2 to 5.8, and MAPE from 14% to 9% (N = 213). Severe eutrophication occurred in the summer and early autumn (June–October). Stepwise multiple linear regression analysis indicated that temperature and wind speed were the two most important meteorological factors influencing eutrophication variability: the temperature accounted for 63% and 55% dynamic eutrophication from FUI-derived and GPR-retrieved results, respectively; the wind speed explained 44% and 52% variability of FUI-derived and GPR-retrieved results.

【 授权许可】

CC BY