Vegetation and Fauna. Environmental Bioindicators from the Lacustrine Water Body

Abstract

The transition from a simple river sector specific to the Eastern Carpathians to a lake basin led to an increase of biodiversity. The assessment of vegetation and fauna from Cuejdel Lake is based on interdisciplinary research in collaboration with biologists. Also, some biological data have been taken from the scientific literature. The results of research led to the determination of 11 habitats, 38 bird species, 8 amphibian species and 2 reptile species in the Cuejdel Lake Nature Reserve. Out of these, in the 2006 modified version (2006/105/CE) of the Habitats (92/43/EEC) and Birds Directives (79/409/EEC) are there is only mention of 5 habitats, 8 species of birds, 3 of amphibians and a single reptile species. The trophicity level in the aquatic environment was based on ecological bio-indices, such as: phytoplankton (50 taxons), vertebrate fauna (17 species) and invertebrate fauna (over 150 taxons). Within the category of invertebrate fauna are included insects (over 100 taxons), zooplankton (14 taxons) and benthic macroinvertebrates (7 taxons). 72 taxons with high density indicate a saprobic value based on dominant or specific valence. Also, have been identified 11 aquatic and palustrine phitocenosis that represent propitious habitats both for the existing species and the new ones. Based on ecological data collected, Cuejdel Lake acts as an oligotrophic aquatic environment with mesotrophic tendencies.