Evolution of an aquatic ecosystem (the Suceava River) for a 3-year period in terms of ecological dynamics

The paper presents the ecological diversity dynamics of an emissary (the Suceava River) in 25 control sections along a 3-year sampling period. The preliminary results of analysis for the biotic communities determined from all 25 locations demonstrated the following aspects: in the upstream and downstream control sections, in terms of phytoplanktonic, zooplanktonic and benthic macroinvertebrates components, the Suceava river and its tributaries water is framed in ‘very good’ and ‘good’ ecological status according to the Romanian Norm (Order MMGA No 161/2006); in the upstream control sections, the phytoplankton is better represented than in the downstream control sections for numerical density and remanent biomass. Also, dominant species in phytoplankton and zooplankton – for numerical density and remanent biomass – are oligo-betamesosaprobic species; concerning the benthic macroinvertebrates there is a quite high diversity, represented by Ephemero- ptera, Trichoptera, Diptera species, and association of the Oligocheta together with Chironomidae organisms. The project goal was estimating the value of the trophic basis, in all control sections of the emissary, because the main actions that must be achieved in these areas in order to accomplish a sustainable management are represented by: the reduction of the nutrient charge in the Suceava River, especially its tributaries inputs, this being the only way to prove the capacity to support the productivity of the entire system.