The recent study, conducted with Landsat images, estimated the amount of chlorophyll-a, an indicator of algal blooms, on Lake Villarrica between 2014 and 2021. It was found, despite the overall good water quality of the lake, chlorophyll-a values increased near the shore and the cities of Villarrica and Pucón. The most important source of nutrients for these blooms came from urban pollution, although agriculture may also have played a role. In fact, the pollution is important enough that the lake is transitioning from an oligotrophic state, with low nutrient levels and high clarity, to a mesotrophic one, with intermediate nutrient levels and biological productivity, he added.
