BASTIDAS NAVARRO marcela Alejandra
congresos y reuniones científicas
IMPACTS AND ONGOING RECOVERY OF PATAGONIAN LAKES FROM THE PUYEHUE-CORDÓN CAULLE MEGA-ERUPTION
MODENUTTI, B. E.; BALSEIRO, E. G.; ELSER, J. J.; BASTIDAS NAVARRO, M. A.; LASPOUMADERES, C.; CUASSOLO, F.; SOUZA, M. S.
Congreso; ASLO Aquatic Sciences Meeting; 2012
The recent mega-eruption (June 2011) in the Puyehue-Cordón Caulle Volcanic Complex ejected large amounts of ash and pumice into the surrounding Andean lakes. To evaluate the impacts of the eruption, we sampled 5 lakes, across a gradient of ash input from September 2011 until March 2012 and compared limnological features after the eruption with data from the preceding decade. Before the eruption, these lakes had very high transparency and low nutrient concentrations indicating ultra-oligotrophic status. However, ash inputs caused an increase up to 14 mg L-1 of total solids, an increase in light attenuation, and (in the two smaller, more strongly affected lakes) an increase in P concentrations. During the growing season (austral spring-summer, September-February) Chl a concentration increased up to 4-fold relative to historical data, even in massive Lake Nahuel Huapi for which only the light environment and not nutrient concentrations were impacted. These data indicate that the volcano eruption modulated production in these oligotrophic lakes by altering light and nutrient supply conditions.