Pollution eutrophication

It is very important to continue investigation and assessment of the impact of the regional climate change, pollution, eutrophication and other human activities on fish stocks and fishing, as well as impact of fishing on the ecosystem state, and to elaborate measures to protect species and habitats. Development of aquaculture could promote restoration of resources and reduction of a fishing pressure on marine living resources and Black Sea ecosystem. 

Keywords Danube River Danube Delta Black Sea pollution eutrophication. 

Water pollution Deposited material or percolate escapes either by surface run-off or by underground movement, threatening streams, rivers, aquifers or the sea Direct poisoning or eutrophication... 

Metal and hydrocarbon pollution and eutrophication that have occurred in the Lagoon of Venice in this century are discussed. 

Ocean prevents eutrophication. Much more water flows into the Mediterranean Sea than is required to replace evaporation from it. The excess, high salinity water exits Gibraltar below the water flowing in af fhe surface. Nufrients that enter the Mediterranean Sea from pollution sources are utilized by marine phytoplankton that sinks and exits with the outflow. Another example is that estuaries often have lower salinity or even freshwater at the surface with a denser saline layer at the bottom. An estuarine circulation occurs with nutrients being trapped in the saline bottom water. 

Cyanides can be fatal to fish at <1 ppm. Because of concern over the possible in vivo conversion of nitrate into carcinogenic nitrosamines, the nitrate content of drinking water must be strictly controlled. Nitrate and phosphate pollution can also cause eutrophication in still or slow-moving warm waters by stimulation of algae growth in the presence of... 

Ammonia and acetic acid in waste water give rise serious pollution problems which bring about eutrophication of rivers, lakes, etc [1, 2]. These have been treated by the conventional method of biological techniques, adsorption, and thermal incineration. A band of researchers have suggested that the ammonia molecules could be transferred to N2 using a photocatalytic redox mechanism as shown follows 4NH3 + 3O2 2N2 + 6H2O. However, it has been... 

Tim Beardsley. Death in the Deep. Scientific American. 277 (Nov. 1997) 17-20. Source for nitrogen-caused eutrophication and runoff pollution. 

The Ebro watershed has a large surface area (85,000 km2) and a complex drainage network (a total of 347 streams). The Ebro is a relatively well known river from the point of view of the biological communities composition. Studies exist on the aquatic fauna and flora [3]. However, the functional activity of the river is largely unknown, mostly because of its complexity and associated technical difficulties. This chapter provides a state-of-the art of the who is who in the biological communities in the river, as well as considerations about the threats imposed by habitat deterioration, eutrophication, pollution and species invasions, and indicates the current gaps that still exist in the knowledge of the river. 

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