| Title | Response of chironomid species (Diptera, Chironomidae) to water temperature: effects on species distribution in specific habitats |
| Abstract | The response of 443 chironomid species to water temperature was analyzed, with the aim of defining their thermal optimum, tolerance limits and thermal habitat. The database included 4442 samples mainly from Italian river catchments collected from the 1950s up to date. Thermal preferences were calculated separately for larval and pupal specimens and for different habitats: high altitude and lowland lakes in the Alpine ecoregion; lowland lakes in the Mediterranean ecoregion; heavily modified water bodies; kryal, krenal, rhithral and potamal in running waters. Optimum response was calculated as mean water temperature, weighted by species abundances; tolerance as weighted standard deviation; skewness and kurtosis as 3rd and 4th moment statistics. The responses were fitted to normal uni- or plurimodal Gaussian models. Cold stenothermal species showed: i) unimodal response, ii) tolerance for a narrow temperature range, iii) optima closed to their minimum temperature values, iv) leptokurtic response. Thermophilous species showed: i) optima at different temperature values, ii) wider tolerance, iii) optima near their maximum temperature values, iv) platikurtic response, often fitting a plurimodal model. As expected, lower optima values and narrower tolerance were obtained for kryal and krenal, than for rhithral, potamal and lakes. Thermal response curves were produced for each species and were discussed according to species distribution (i.e. altitudinal range in running water and water depth in lakes), voltinism and phylogeny. Thermal optimum and tolerance limits and the definition of the thermal habitat of species can help predicting the impact of global warming on freshwater ecosystems. |
| Source | Journal of entomological and acarological research 45 (2), pp. 73–89 |
| Keywords | Sistemi di Approvvigionamento Idrico; Early-Warning di scarsità idrica |
| Journal | Journal of entomological and acarological research |
| Editor | Università degli Studi di Milano, Milano, Italia |
| Year | 2013 |
| Type | Articolo in rivista |
| DOI | 10.4081/jear.2013.e14 |
| Authors | Marziali, L.; Rossaro, B. |
| Text | 342267 2013 10.4081/jear.2013.e14 ISI Web of Science WOS BCI201300771694 Sistemi di Approvvigionamento Idrico; Early Warning di scarsita idrica Response of chironomid species Diptera, Chironomidae to water temperature effects on species distribution in specific habitats Marziali, L.; Rossaro, B. CNR IRSA Water Research Institute, U.O.S. Brugherio, Brugherio MB ; Department of Food, Environmental and Nutritional Sciences DeFENS , University of Milan, Milan, Italy; The response of 443 chironomid species to water temperature was analyzed, with the aim of defining their thermal optimum, tolerance limits and thermal habitat. The database included 4442 samples mainly from Italian river catchments collected from the 1950s up to date. Thermal preferences were calculated separately for larval and pupal specimens and for different habitats high altitude and lowland lakes in the Alpine ecoregion; lowland lakes in the Mediterranean ecoregion; heavily modified water bodies; kryal, krenal, rhithral and potamal in running waters. Optimum response was calculated as mean water temperature, weighted by species abundances; tolerance as weighted standard deviation; skewness and kurtosis as 3rd and 4th moment statistics. The responses were fitted to normal uni or plurimodal Gaussian models. Cold stenothermal species showed i unimodal response, ii tolerance for a narrow temperature range, iii optima closed to their minimum temperature values, iv leptokurtic response. Thermophilous species showed i optima at different temperature values, ii wider tolerance, iii optima near their maximum temperature values, iv platikurtic response, often fitting a plurimodal model. As expected, lower optima values and narrower tolerance were obtained for kryal and krenal, than for rhithral, potamal and lakes. Thermal response curves were produced for each species and were discussed according to species distribution i.e. altitudinal range in running water and water depth in lakes , voltinism and phylogeny. Thermal optimum and tolerance limits and the definition of the thermal habitat of species can help predicting the impact of global warming on freshwater ecosystems. 45 Published version Articolo in rivista Universita degli Studi di Milano 2038 324X Journal of entomological and acarological research Journal of entomological and acarological research J. entomological acarological research Journal of entomological and acarological research. laura.marziali MARZIALI LAURA TA.P04.005.006 Gestione a scala di bacino delle risorse idriche e sostenibilita dell uso irriguo in agricoltura |
