Computational experimentsin searching of nitrogen and phosphorus disbalance appearance in Azov sea

As a result of computer calculations it is determined that the main reason for a simultaneously increase of nitrogen and diminution of phosphorus quantities in Azov sea (1970–1980 years) was the reduction of water flow of the river Don. With the aid of special model experiments we evaluate the influence of “purely” biological and “purely” hydrological processes for the water reservoir. We demonstrate the mechanism of interaction of this factors, causing the disbalance of nitrogen and phosphorus quantities under the decreasing of Don water flow.