关键词: 水质监测; 时空变化; 叶绿素a浓度; 透明度; 富营养化指数; GF-1卫星影像; 洱海;

Abstract: In order to explore the variation law of water quality and its driving factors of Erhai Lake in dry season from 2014 to 2019,GF-1 remote sensing image data of January and November form 2014 to 2019 were selected to invert the water quality of Erhai Lake based on chlorophyll-a concentration and transparency and eutrophication index.The results showed that:(1) In terms of time scale, the chlorophyll-a concentration and eutrophication index of Erhai Lake decreased year by year from 2014 to 2019,the transparency increased gradually, and the water quality was gradually improved in dry season.(2) In terms of spatial scale, chlorophyll-a concentration and eutrophication index of Erhai Lake in November from 2014 to 2019 were lower in the north and higher in the south, while transparency was higher in the north and lower in the south, demonstrating that water quality was better in the north and worse in the south.And the chlorophyll-a concentration in January was higher in the central part and lower in the south and north, and the water quality was better in the north, while the transparency decreased from north to south and the eutrophication index increased from north to south.(3) The chlorophyll-a concentration and eutrophication index of Erhai lake were significantly positively correlated with total nitrogen and total phosphorus(P<0.05),while the water transparency was significantly negatively correlated with total nitrogen and total phosphorus.

Key words: water quality monitoring; temporal and spatial variation; chlorophyll-a concentration; transparency; eutrophication index; GF-1 remote sensing image; Erhai Lake;