The freshwater pearl musel (Margaritifera margaritifera) is critically endangered species. Its survival depends on the abundance of host fish (Salmo trutta m. fario), on which early mussel stages parasitize. More important is to preserve suitable environment of unpolluted cold rivers with corresponding extensive management of surrounded landscape. To preserve population of pearl mussel in Czech Republic it is essential to describe environmental conditions necessary for its survival. In this study, we observed the influence of water temperature on the abundance of populations of pearl mussel and the individual quantity change after introduction of a new nutriet source. This source is represented by the nutrient stream, flowing through the adjacent grassland with the wide outfall into the river. For the monitoring, the pearl mussels were distinguished into two groups: juvenile and adults forms. The results were evaluated for the both groups separately. We found significant difference between each year, for both, juvenile and adult stage. The year 2009 was an exception, because the difference in the number of adults was not observed. We noticed substantial increase of the number of observed juvenile individuals during summer. The quantity was in direct proportion with the water temperature, but the influence of tempeature was not statistically proved.
Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:137808 |
Date | January 2012 |
Creators | TULACHOVÁ, Marie |
Source Sets | Czech ETDs |
Language | Czech |
Detected Language | English |
Type | info:eu-repo/semantics/masterThesis |
Rights | info:eu-repo/semantics/restrictedAccess |
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