Smartphone photo based water quality monitoring algorithm and application

doi:10.11947/j.AGCS.2022.20220049

Abstract

Abstract: Smartphones provide a new means for water quality monitoring based on citizen science, but there is still a lack of systematic research on water quality parameter inversion based on water surface photos taken by smartphones. In view of this situation, this study firstly developed models to retrieve typical water quality parameters and identify typical water pollution, including Forel-Ule index, water clarity, trophic state, cyanobacterial bloom, and black and odorous water. Then, based on these models, the “Water Color Watch” app based on smartphone Android system was developed. The app was applied and evaluated in several typical study areas, and obtained good accuracy in monitoring of water quality. Finally, the impacts of white balance, different digital cameras and photo storage formats on water quality monitoring based on smartphone and their coping strategies were analyzed. The results of this study will help to promote the wide application of smartphones in water quality monitoring.

Key words: Smartphone, digital image, water quality monitoring, citizen science, water color watch, app

CLC Number:

P227

LI Junsheng, GAO Min, ZHANG Bing, ZHANG Fangfang, WANG Shenglei, YIN Ziyao, XIE Ya. Smartphone photo based water quality monitoring algorithm and application[J]. Acta Geodaetica et Cartographica Sinica, 2022, 51(4): 568-576.

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