Browsing by Autor "Beatriz Modenutti"

Now showing 1 - 2 of 2

Andean Lakes: a proposal for lake districts
(Taylor & Francis, 2024) Pablo Prado; Beatriz Modenutti; Nelson Aranguren-Riaño; Esteban Balseiro; Iris Samanez; Melina Campero; Carla E. Fernández; Carlos Rondón; Fernando M. Carvajal‐Vallejos; D. Mabel López-Paría
The Andes, the world’s longest mountain system (8500 km), harbour important headwater systems that constitute crucial water resources for South America. Their complex topography significantly influences climate and hydrology. The Andes have a wide diversity of aquatic environments, with >5000 lakes (>0.1 km2, permanent and excluding constructed reservoirs) with different morphometry, including the largest and the deepest in South America (Titicaca and Viedma, respectively). We applied a grouping analysis based on available systematised information to delimit different lake districts along the Andes. More than 60% of the surface area of all Andean lakes is concentrated in only 9 large lakes, and >80% of the lakes are <1 km2. This analysis proposes 11 lake districts, including 2 in the North Andes, 6 in the Central Andes, and 3 in the South Andes. Each lake district is described based on the different morphologies, geological origins, climatic factors, and available limnological information. We believe this study will benefit not only scientists but also decision-makers and stakeholders working in integrated water resource management in a region subject to climate change and socioeconomic inequalities.
Andean lakes: endangered by natural and anthropogenic threats
(Taylor & Francis, 2024) Melina Campero; Esteban Balseiro; Carla E. Fernández; Beatriz Modenutti; Pablo Prado; Carlos Rondón; Fernando M. Carvajal‐Vallejos; Yimy Herrera-Martínez; D. Mabel López-Paría; Nelson Aranguren-Riaño
The Andes mountains extend north–south in a latitudinal gradient of 8500 km. Because of the great climatic variety and the peculiar north–south orographic distribution, lakes are highly diverse, including different lake origins and contrasting morphometries. We reviewed >700 ecological studies on Andean lakes to identify the main threats to these freshwater systems. The most important threats are UV radiation, changes in water balance, and eutrophication, all 3 interacting with climate change, alien species introductions, and mining. UV radiation is an important factor in Andean lakes not only because of the altitude but also because many lakes are included in the Antarctic ozone hole. The introduction of alien species, particularly exotic salmonids, also had detrimental effects, affecting native fish populations and behaviour and endemic species by disrupting the indigenous food web. Eutrophication and browning caused by human activities, including land use interacting with climate change, are increasing in Andean lakes, causing a decrease in water quality. Finally, mining can cause water contamination (both groundwater and surface water) by chemicals emitted from mining processes, thus producing a loss of biodiversity. Although an important number of Andean lakes have been declared as Ramsar sites because of their uniqueness and their extreme conditions, they are subject to significant human impacts. Here, for the first time, we identify these impacts all along the Andes; however, further studies at different scales are mandatory if we hope to understand, conserve, and manage Andean lakes.