The main aim of this contribution is to evaluate the vulnerability of Lake Garda, the largest Italian lake, respect to specific human stressors (e.g. nutrients, hydroelectrical exploitation) in a climate change scenario and through a palaeolimnological approach. Lake’s sediments have been studied within the EuLakes project (Reg. Nr. 2CE243P3) and results are being used to determine the lake reference conditions before stronger human impact. The deeper basin (350 m) of the Lake is less impacted by human activities and is suitable for reconstruction of long term environmental variability, including climate change and its effects on lake ecology. In contrast, the shallower basin (81 m) is strongly affected by tourism and intensive agriculture, and thus is more suitable for studies on lake eutrophication. This contribution focusses on changes in sub-fossil diatom assemblages and TP reconstruction of two short sediment cores collected from the deepest point of the two basins. The core collected at 350 m presents two discontinuities. The deepest one dates in the mid 1940s and shows a decrease in benthic taxa, which may be related with the intensive hydroelectrical exploitation of the catchment area. The second discontinuity is in early 1960s and coincids with an increase in Fragilariaceae respect to centric taxa, the result of nutrient enrichment and climate change. The core from the shallower basin does not show discontinuities, though the diatom assemblages show a decrease in both mesotrophic Fragilariaceae and Cyclotella spp. since the middle 1960s. A preliminary diatom based reconstruction of lake TP concentration over the last 200 years confirm the decadal limnological data.
|Citation:||Milan, M.; Bigler, C.; Tolotti, M. (2013). Paleo-ecological reconstruction of the secular evolution of the largest Italian lake (Lake Garda). In: Conference Paleoecological reconstructions: lacustrine, peat and cave sediments, 22nd - 24th May 2013, Białka Tatrzańska, Poland: 34. url: http://paleo2013.ing.pan.pl/ handle: http://hdl.handle.net/10449/22251|
|Organization unit:||Sustainable Agro-Ecosystems and Bioresources Department # CRI_2011-JAN2016|
|Authors:||Milan, M.; Bigler, C.; Tolotti, M.|
|Title:||Paleo-ecological reconstruction of the secular evolution of the largest Italian lake (Lake Garda)|
|Scientific Disciplinary Area:||Settore BIO/07 - Ecologia|
|Appears in Collections:||03 - Conference object|