EUTROPHICATION AND POLLUTION DEVELOPMENT IN THE DANUBE RIVER AND COASTAL MARINE ZONE SYSTEM

Abstract

Since the 1970s, the process of anthropogenic water euthrophication and the near bottom hypoxia linked with it, have caused widespread benthos fauna mortality. In addition to this negative phenomenon a lot of contaminations and pollutants are washed out from the fields and the coastal urban agglomerations by the river flow. In the process of sedimentation, the suspended matter is accumulated in the bottom sediments. It reinforces negative changes in benthic habitat conditions. One of the main modern problem is eutrophication and pollution (waste) in rivers, lakes and coastal marine systems. It illustrates the development of eutrophication and waste in a large, deep lake, together with the impacts on the lake and marine ecosystems. The Object of investigation is the Danube mouth area. The Subject of investigation is euthrophication processes and pollution input development in aquatic system. The Danube river extends almost all over Central Europe, which means that any waste from factories located directly near the Danube will inevitably get there. Therefore, the phenomenon of "water bloom" and periodic environmental disasters on the Danube are natural consequences of human activities. The level of pollution of the bottom sediments in the Northwest shelf of the Black Sea is examined. Modern data are compared with those of the late 20th century and their variability over 20 years. Substantial increase (by two orders) of copper, lead and nickel concentration has been marked. The diverse of contamination sources in larger catchment areas usually produce a mixture of pol­lutants, which is more difficult to treat than an industrial waste. For most sediments, there are more arguments in favor of disposal rather than treatment. Mechanical separation of the less contaminated fractions could be a useful step prior to the final stor­age of the residues. To improve the status of surface water bodies in the management area, it is necessary to take into account and reduce all existing factors and risks of deterioration of water quality. Environmental issues and the science behind them are of great public concern. Water management issues are also of critical importance. Human impacts within the river – delta –sea system are environmental contamination with nutrients, heavy metals, organic compounds, etc., degrading water and sediment quality and leading to toxic impacts in biota, airborne pollution. Human impacts from outside of the wetland are lack of catchment scale management of land use upstream, leading to soil erosion and sedimentation.