Alain Maasri, PhD.Mediterranean Institute of Ecology and PaleoecologySpeaker info and contact on www.alainmaasri.com Université Paul Cézanne 13397 Marseile cedex 20 - France |
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Better understanding for a better use: a Chironomid study case |
| Chironomids are among the most abundant, diverse and widespread insects in the freshwater ecosystems. These features established them as a major biological tool in different ecology fields as the biodiversity assessment, the water quality assessment, eco-toxicological studies and Paleolimnology. I’m going to present my research activity dealing with two aspects of the chironomid ecology, 1) the food chains and the foraging behavior of grazing rheophilic larvae and 2) the hydraulic preferences of benthic chironomid larvae.
Results from my study on the food-web structure in highly nutrient-enriched streams dealing with the chironomid community structure, the epilithon and the foraging behavior of chironomids, will be presented. Water chemistry, epilithon biomass, epilithic algal biomass, algal biovolumes, and algal composition were analyzed to determine their association with density and taxonomic composition of epilithic chironomids. Significant correlations were found between chironomid larval densities and total algal cell densities and biovolumes. Several contrasting trends were identified in the relationships between chironomid and algal assemblages, and the foraging behavior of the dominant chironomid taxa added significant elements to explain the success of such taxa in high nutrient enriched streams. I will also present briefly my ongoing research activity on the hydraulic preferences of chironomid taxa. Bed shear stress describes the velocity close to the streambed, and is considered as a key element used to model substrate movement and the hydraulic condition at a microhabitat scale. FST hemispheres technique was uses, and FSTress preference curves will be elaborated for chironomid genera and species. Results will add valuable information to predict changes in the chironomids community structure under minimum flow rehabilitations scenarios; But also for river management policies and paleolimnological studies. |
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Ort |
| 25.06.2009 16:00 Uhr Großer Hörsaal |
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