Abstract: [Purposes]A nutrient enrichment inversion model for aquaculture sea areas based on ZY-1 hyperspectral images is constructed to provide scientific reference for marine fishery management and marine environmental protection.[Methods]Using Zhao'an Bay and Dongshan Bay in Fujian province as research areas,we select 4 spectral bands with the strongest correlation to the logarithm of COD,DIP,and DIN based on measured spectral reflectance,water quality data,and ZY-1 hyperspectral imagery.Three models (CatBoost,random forest,and multiple linear regression) are developed.After precision evaluation,the optimal model is identified to assess eutrophication status and conduct spatiotemporal feature analysis.[Findings]Results show that the CatBoost model demonstrated higher inversion accuracy.The R² values for COD,DIP,and DIN are 0.80,0.71,and 0.88,respectively.[Conclusions]The inversion results reveal significant seasonal variations in Zhaoan Bay's eutrophication index,showing higher levels in some areas during autumn and lower levels in spring and winter.Dongshan Bay exhibit better overall water quality than Zha'an Bay,with most regions maintaining low eutrophication indices across different periods,indicating relatively good water conditions.

Key words: eutrophication, aquaculture, ZY-1 satellite, CatBoost, random forest