1,721,021 research outputs found
Limnological research in the deep southern subalpine lakes: synthesis, directions and perspectives
No full textBased on a selection of 230 papers published during the last 15 years in international journals, the present work aims at evaluating the state of the art of limnological research in the deep southern subalpine lakes (DSL: Garda, Iseo, Como, Lugano and Maggiore). Historically, most of the limnological research was fostered by the need to find solutions to the problems connected with eutrophication and pollution. Many data are available on the thermal structure, algal nutrient concentrations and phytoplankton of the DSL, while other topics still remain more or less constrained to single lakes. Apart from this geographical bias, a number of aspects emerged from this synoptic view. Limnological research is still linked to the concept of scientific monitoring, while experimental studies and modelling are confined to specific niches; the integration of different disciplines is held back by the division of studies on different compartments; integration of studies and synoptic analyses at a macro regional scale have been carried out only for specific research areas. The DSL are increasingly threatened by new pressures (climatic change, excessive proliferation of toxic cyanobacteria, introduction of new species and new micropollutants) and by the interactions among these new and old stressors. In this rapidly changing situation, the paper emphasises the need to define criteria to be used to distinguish research able to produce relevant results and predictive models, which are essential elements for an efficient management of water resources
Physico-chemical and biological aspects of Lake Albano.
No full textLake Albano is deep and has a small surface area, which reduces the potential for mixing across its full depth. This can lead to dangerous accumulations of carbon dioxide in the bottom waters of the lake deriving from subterranean magmatic processes. It has been proposed that limnic gas eruptions emanating from these deep waters represent the most significant present-day natural hazard of the Colli Albani volcano. Although recent evidence has shown that the lake is not meromictic and that rare full mixing events do occur, reducing to some extent the risk of limnic eruptions. At present the lake volume and water quality is rapidly decreasing due to over-abstraction and uncontrolled inputs of waste and sewage. These conditions may be responsible for large growths of toxic cyanobacteria in the lake. Lake water concentrations of microcystins (a cyanobacterial toxin) are well above the recommended limits set for drinking water, and some trace groundwater contamination has also been determined. These toxins can cause the death of animals and pose a significant risk to human health, representing a secondary hazard of the lak
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