A Novel Approach to Monitoring the Quality of Lakes Water by Optical and Modeling Tools: Lake Sevan as a Case Study

The geo-ecosystems of the lakes play an important role in their wider geographical areas, such as energy and biological resources, as well as water sources for agriculture, industry, and drinking water. The main goal of the present paper is to develop a new approach to the effective monitoring of lakes water quality. Three new optical decision-making systems (ODMS) are being set up first as components of this new monitoring system. The first ODMS is based on an 8-channel universal spectrophotometer. The second involves a 35-channel spectrophotometer to diagnose water sampling and the third includes a 128-channel spectroellipsometer. All versions of ODMS include special software that incorporates algorithms and models to solve optical inverse tasks and decision making about the quality of lakes water. ODMS provides a spectral image of the water quality of the lakes in wavelengths ranging between 350 and 910 nm depending on the optical device. The recognition of spectral images generated by ODMS allows the detection of adverse changes in water quality and the decision-making on the choice of strategy to deal with this change. In particular, a case study of Lake Sevan in Armenia is being conducted for the ODMS demonstration, and the results of the lakes water diagnosis are being discussed. The ODMS estimate for water quality error does not exceed 18%, while the forecast for water quality for 1 month includes an error not exceeding 10% and 20% for 1 year.