Volcanic eruptions and glacier recession: understanding the effects of particle inputs on planktonic communities of Andean–Patagonian lakes

MODENUTTI, BEATRIZ; BALSEIRO, ESTEBAN; LASPOUMADERES, CECILIA; SCHENONE, LUCA; BASTIDAS NAVARRO, MARCELA; MARTYNIUK, NICOLÁS

JOURNAL OF PALEOLIMNOLOGY

SPRINGER

Año: 2024

0921-2728

Lakes are particularly vulnerable toenvironmental changes and thus considered sentinelsand integrators of processes that occur in theatmosphere and terrestrial environments. Individualup to ecosystemic metabolic pathways and nutrientcycling in lakes respond to both natural and humandisturbances. Disentangling the effect of such differentforces is a particular challenge for lake ecologicalstudies. Here we present a conference paperbased on previous studies carried out in Andean-Patagonian lakes under two important events: thePuyehue–Cordón Caulle eruption in 2011 and theglacial recession with a glacial lake outburst flood(GLOF) in 2009. We discuss how biological variablesresponded to these two natural events that producedthe input of minerogenic inorganic particles into thelakes. We present the combination of observationaland experimental research, including new molecularmethods, that contributed to understanding the effectsof these inorganic particles on aquatic ecosystems.Both events involved changes in the transparency ofthe lakes that affected phytoplankton parameters (biomassvertical distribution), bacteria composition andcommunity structuring process. Finally, both eventshad very contrasting effects on zooplankton, in thesame range of particle concentrations. Particles fromglacial melting are beneficial for daphnids reducingthe impact of ultraviolet radiation and increasing thequality of the food. In contrast, volcanic ashes areabrasive materials that have a deleterious effect forfiltering zooplankton.