Chlorophyll has been commonly used to estimate algal biomass and trophic levels of lakes. Chlorophyll, being the result of interactions between physical, chemical and biological factors, can also show the effects of human impacts, such as fish introduction or removal, or water-level fluctuations, correlated to the use o f lakes as reservoirs. Beyond the more traditional use for rhe assessment of trophic status, chlorophyll determinations may also be of interest in the context of regional studies to improve the characterisation of high mountain lakes. The seasonal study of chlorophyll concentrations in two lakes suggested a temporary change of the trophic level in Tre Laghi and showed differences in the amount of primary production in two apparently similar lakes. A possible explanation might be a higher grazing pressure on phytoplankton occurring in Lake Serodoli, where fish is lacking, while Lake Tre Laghi is occasionally and illegally stocked with young Salvelinus fontinalis and Salmo trutta forio, which live on zooplankton. However, in discussing the biological differences between the two lakes, the exploitation of the water of Lake Serodoli should also be considered. Indeed until 1990 the lake was almost emptied in winter for hydroelectric purposes by means of a pipe located at a depth of 20 m; today 50-60 L s-' are taken away in winter as drinking water, causing a water level reduction of 3-4 m only. Additional data must be collected for a deep understanding of this situation, indicating the need for detailed limnological research even in apparently undisturbed high mountain lakes in Nature Parks in ltaly.
Tolotti, M., Cantonati, M. (2000). Temporal and vertical variations of chlorophyll concentrations in high mountain lakes of the Adamello-Brenta Regional Park (Trentino, Italy). VERHANDLUNGEN - INTERNATIONALE VEREINIGUNG FUR THEORETISCHE UND ANGEWANDTE LIMNOLOGIE, 27(1), 521-526 [10.1080/03680770.1998.11901287].
Temporal and vertical variations of chlorophyll concentrations in high mountain lakes of the Adamello-Brenta Regional Park (Trentino, Italy)
Cantonati, M.Ultimo
2000
Abstract
Chlorophyll has been commonly used to estimate algal biomass and trophic levels of lakes. Chlorophyll, being the result of interactions between physical, chemical and biological factors, can also show the effects of human impacts, such as fish introduction or removal, or water-level fluctuations, correlated to the use o f lakes as reservoirs. Beyond the more traditional use for rhe assessment of trophic status, chlorophyll determinations may also be of interest in the context of regional studies to improve the characterisation of high mountain lakes. The seasonal study of chlorophyll concentrations in two lakes suggested a temporary change of the trophic level in Tre Laghi and showed differences in the amount of primary production in two apparently similar lakes. A possible explanation might be a higher grazing pressure on phytoplankton occurring in Lake Serodoli, where fish is lacking, while Lake Tre Laghi is occasionally and illegally stocked with young Salvelinus fontinalis and Salmo trutta forio, which live on zooplankton. However, in discussing the biological differences between the two lakes, the exploitation of the water of Lake Serodoli should also be considered. Indeed until 1990 the lake was almost emptied in winter for hydroelectric purposes by means of a pipe located at a depth of 20 m; today 50-60 L s-' are taken away in winter as drinking water, causing a water level reduction of 3-4 m only. Additional data must be collected for a deep understanding of this situation, indicating the need for detailed limnological research even in apparently undisturbed high mountain lakes in Nature Parks in ltaly.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
