Poster Presentation Society for Freshwater Science 2025 Annual Meeting

Temporal shifts in water quality in freshwater systems in Lake Atitlán Basin (117928)

Natalia Vargas López 1 2 , Estuardo Bocel 2 3 , Mónica Martínez 2 , Krista Capps 1 4
  1. Odum School of Ecology, University of Georgia, Athens, GEORGIA, United States
  2. Centro de Estudios de Atitlán, Universidad del Valle de Guatemala, Sololá, Guatemala
  3. Department of Natural Resources & Environmental Science, University of Reno, Reno, NEVADA, United States
  4. River Basin Center, University of Georgia, Athens, GEORGIA, United States

Some of the most significant threats to tropical freshwater systems include land cover change, nutrient input, and eutrophication. These pressures often lead to eutrophication and intensified algal blooms, which can degrade water quality and disrupt ecosystem services. In the Guatemalan highlands, freshwater systems in Lake Atitlán basin are subject to several anthropogenic pressures e.g., land conversion, which can cause cultural eutrophication. Here, the caldera Lake Atitlán and the perennial rivers that drain into it, have shown changes in their water quality, yet long-term patterns in river water quality remain poorly understood. My research aims to (i) identify patterns of land cover change within the basin, with a particular focus on riparian zones, and (ii) analyze water quality data from the Centro de Estudios de Atitlán to explore the relationships between land cover changes and water quality in rivers and the lake. I expect the results to reveal patterns of land cover change in the basin, with a specific focus on how riparian areas have been modified from 2016 to 2023. Additionally, I anticipate identifying trends in nutrient concentrations, including PO₄, NH₄, and NO₃+NO₂, in river samples from San Francisco, Quiscab, and La Catarata over the same eight-year period. I also aim to show how nutrient concentrations in rivers impact concentrations in the lake. These results will allow to better understand how anthropogenic activities in the basin's terrestrial regions influence the physicochemical conditions of its freshwater systems. Insights into the long-term dynamics of land cover change and river systems will help inform management strategies aimed at preserving the lake's ecological integrity while supporting the cultural traditions of the region.