Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Secular ecological evolution of Lake Ledro (Trentino) as outlined by paleolimnological studies |
| Abstract | Lake Ledro (zmax=48 m) is an hardwater, mid-altitude (650 m a.s.l.) lake located in SW Trentino (Eastern Italian Alps). It has been modified for hydroelectric exploitation since the late 1920s and at present represents a relevant socio-economic resource for the region in relation to recreation and summer tourism. The lake underwent anthropogenic eutrophication from the 1970s to the 1980s, which has been followed by water quality improvement over the past two decades, after the sewage treatment of municipal wastewater. Despite the present lake mesotrophic conditions, cyanobacteria contribution recently increased, culminating in a very intense bloom of Planktothrix rubescens in autumn-spring 2009/2010. The Autonomous Province of Trento promoted a multidisciplinary research project aimed at understanding the environmental and biotic factors driving the development of P. rubescens populations in Lake Ledro. Within the project, a complementary paleoecological investigation was conducted in order to reconstruct the lake secular trophic evolution (thus identifying its reference conditions) and the variations of P. rubescens in relation to climatic variability, human impact and lake basin management. Several short sediment cores were retrieved from the deepest point of the lake in winter 2011. The master core (83 cm long) was dated based on Pb and Cs radioisotopes, and subsamples were analysed for basic geo-chemical proxies (i.e. wet density, and water/organic content). Biological proxies included sub-fossil algal and cyanobacteria pigments and diatom remains. A parallel sediment core (78 cm long) was opened longitudinally in order to analyse the varved structure of the sediment and to identify the records of major hydrological related events occurred during the last few centuries. The present contribution reports the preliminary results obtained during the study of the sediment cores. The results are discussed comparing the secular trends with the data recently recorded during the limnological surveys. |
| Source | AIOL: XXI Congresso dell'Associazione Italiana di Oceanologia e Limnologia: Limnologia e Oceanografia nel Terzo Millennio: nuove frontiere o assenza di frontiere?, Lignano Sabbiadoro (UD), 23-26 settembre 2013Atti dell'Associazione italiana di oceanologia e limnologia, pp. 109–109 |
| Keywords | Lake LedroTrophic evolution |
| Journal | Atti dell'Associazione italiana di oceanologia e limnologia |
| Editor | AIOL., Verbania Pallanza, Italia |
| Year | 2013 |
| Type | Abstract in atti di convegno |
| Authors | Monica Tolotti; Adriano Boscaini; Andrea Lami; Handong Yang; Nico Salmaso |
| Text | 314152 2013 Lake Ledro Trophic evolution Secular ecological evolution of Lake Ledro Trentino as outlined by paleolimnological studies Monica Tolotti; Adriano Boscaini; Andrea Lami; Handong Yang; Nico Salmaso Monica Tolotti, Adriano Boscaini, Nico Salmaso IASMA Research and Innovation Centre, Fondazione Edmund Mach, Italy; Andrea Lami CNR ISE, Pallanza Verbania; Handong Yang University College London, Environmental Change Research Centre, U.K. Published version ID_PUMA cnr.ise/2013 B6 010. Acronimo titolo evento AIOL AIOL XXI Congresso dell Associazione Italiana di Oceanologia e Limnologia Limnologia e Oceanografia nel Terzo Millennio nuove frontiere o assenza di frontiere Lignano Sabbiadoro UD 23 26 settembre 2013 Nazionale Contributo Lake Ledro zmax=48 m is an hardwater, mid altitude 650 m a.s.l. lake located in SW Trentino Eastern Italian Alps . It has been modified for hydroelectric exploitation since the late 1920s and at present represents a relevant socio economic resource for the region in relation to recreation and summer tourism. The lake underwent anthropogenic eutrophication from the 1970s to the 1980s, which has been followed by water quality improvement over the past two decades, after the sewage treatment of municipal wastewater. Despite the present lake mesotrophic conditions, cyanobacteria contribution recently increased, culminating in a very intense bloom of Planktothrix rubescens in autumn spring 2009/2010. The Autonomous Province of Trento promoted a multidisciplinary research project aimed at understanding the environmental and biotic factors driving the development of P. rubescens populations in Lake Ledro. Within the project, a complementary paleoecological investigation was conducted in order to reconstruct the lake secular trophic evolution thus identifying its reference conditions and the variations of P. rubescens in relation to climatic variability, human impact and lake basin management. Several short sediment cores were retrieved from the deepest point of the lake in winter 2011. The master core 83 cm long was dated based on Pb and Cs radioisotopes, and subsamples were analysed for basic geo chemical proxies i.e. wet density, and water/organic content . Biological proxies included sub fossil algal and cyanobacteria pigments and diatom remains. A parallel sediment core 78 cm long was opened longitudinally in order to analyse the varved structure of the sediment and to identify the records of major hydrological related events occurred during the last few centuries. The present contribution reports the preliminary results obtained during the study of the sediment cores. The results are discussed comparing the secular trends with the data recently recorded during the limnological surveys. Secular ecological evolution of Lake Ledro Trentino as outlined by paleolimnological studies 2013_B6_010_0.pdf Abstract in atti di convegno AIOL. 1129 5589 Atti dell Associazione italiana di oceanologia e limnologia Atti dell Associazione italiana di oceanologia e limnologia Atti Assoc. ital. oceanol. limnol. andrea.lami LAMI ANDREA TA.P02.014.002 Impatto dei cambiamenti globali sugli ecosistemi acquatici |