0.3; number of plankton alga species - 13; number of higher water plant 

 species - 7; number of groups of zoobenthos organisms - 3; number of phyto- 

 plankton organisms - 2,170 thousand cells/liter; number of zooplankton or- 

 ganisms - 35 thousand specimen/m 3 ; number of 01 igochaeta - 33,780 specimen/ 

 m 2 ; mean protective covering of higher water plants - 50%; biotic potential 



- 2 points; total quantity of bacteria - 3.6 million/ml; number of spore- 

 forming bacteria in 1 ml - 200. 



In the region 85 km from the mouth of the Moscow River, the water qual- 

 ity has considerably increased due to the development of self-purification 

 processes. Production processes are increased with the relative decrease 

 in destruction processes. The number of plankton organisms increases. 

 Species variety is increased. The greatest number of species of algae and 

 higher water plants in the lower Moscow River fow are located here. Benthic 

 organisms are represented by five systematic animal groups, and the number 

 of chironomid species increased to four. The indication according to sapro- 

 bility of plankton forms demonstrated that they are completely devoid of 

 polysaprobic species and that the a-mesosaprobic species approaches the 

 minimum. Bacterial pollution is also considerably decreased. Thus, the 

 water of the Moscow River in the 85 km region may be characterized on the 

 whole as slightly polluted. The following data do not contradict this con- 

 clusion: Primary gross production - 2.56 mg 02/liter for a 24-hr period; 

 demand - 1.41 mg 2 /liter for a 24-hr period; P/R ratio - 1.8; number of 

 plankton alga species - 20; number of higher macrophytes - 12; number of 

 phytoplankton organisms - 9,300 thousand cells/liter; number of zooplankton 

 organisms - 20,000 thousand specimen/m 3 ; number of 01 igochaeta - 16,130 

 specimen/m 2 ; relative number of 01 igochaeta - 80%; mean protective covering 

 of higher macrophytes - 70%; biotic potential - 4 points; total number of 

 bacteria - 2.5 million mg/liter; number of saprophitic bacteria - 10 thou- 

 sand/ml; the ratio of the total number of bacteria to the number of sapro- 

 phitic bacteria - 250. 



In the Kolomna region, due to the fact that self-purification processes 

 are developed here to the greatest extent, a further increase in water qual- 

 ity is taking place and indices of oligosaprobility appear. The number of 

 organisms increased: The number of phytoplankton organisms approaches 13 

 million cells/liter, and zooplankton - 206 thousand specimen/m 3 . The 

 species variety of zooplankton is sharply increased mainly due to Rotifera . 

 Production processes reach their highest intensity - 6.12 mg 2 /liter for a 

 24-hr period. According to all the indices of benthic organisms develop- 

 ment, the river is also characterized by a very slight pollution; the number 

 of zoobenthos groups - 6; the number of 01 igochaeta - 1920 specimen/m 2 

 (lower than in the vicinity of Zvenigorod); relative number of 01 igochaeta 



- 11%, etc. 



However, the water quality in the vicinity of Kolomna does not reach 

 the level which is observed in the vicinity of Zvenigorod. Actually, 

 according to a number of indices, higher water quality near Kolomna is not 

 expressed so clearly: The decrease in bacterial pollution is not so rapid; 

 destruction processes are increased; in comparison with the 85 km outlet, 

 the decrease in species variety for plant organisms (phytoplankton and 



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