|Timeline:||October 2016 - 9 October 2020|
Water quality is related to the ecological environment, water cycle dynamics as well as to human impacts on water resources. The use of water color as a surrogate or proxy for water quality is rapidly increasing, due to the rapid expansion of smart phone applications as citizen tool for watching and monitoring aquatic environments. However, water color and water quality mean different things and more in-depth scientific understanding is urgently required on how and where water color apps can meaningfully contribute to water quality monitoring and assessment.
The main objective of this research is to investigate relationships between water colour and water quality and biogeochemistry. Then, apply this study to citizen science and satellite monitoring of water quality. For this purpose, these sub-objectives should be achieved:
1. To analyse the relationship of biogeochemical parameters and digital image values, substitute colorimetry for spectrometry, meanwhile use the spectrometers as validation.
2. To retrieve water quality from water colour analysis, improve the accuracy of digital imaging colorimetry for water monitoring.
3. To apply the relationships between water colour spectra and biogeochemistry to a large scale monitoring of water quality (e.g. smartphone APPs data, satellite data)
By measuring water colour with a built digital colorimetry kit, the relationships between RGB imagery, as used in smartphones, and water biogeochemical parameters will be studied on both artificial water – constituent mixtures in the laboratory as well as in natural waters. Meanwhile, by combining these water colour experiments with more precise hyperspectral spectrometer measurements in the lab and field, the accuracy of the rapid RGB water colour apps will be evaluated. Moreover, the relationships found between the water colour spectra and the biogeochemistry of the waters will then be applied to a look-up database, which can then be used for improved water quality retrieval from rapid water colour analysis and even for upscaling to satellite data.
Keywords: Water colour, biogeochemistry, water quality, colorimetry, water spectrometry