The requirement to keep the reclamation of the unique lake in its natural state as natural monuments. to carry out activities to preserve their natural conditions, in unfavorable cases, to carry out their reclamation (cleaning of debris, sediments, sapropel), as well as on all lakes to protect their water from pollution by untreated sewage, pesticides and fertilizers.
Reclamation activities should be aimed at increasing the productivity of water bodies for hunting and fisheries, which depends on lake levels, water in reservoirs and its distribution along the seasons of the year, of entry and removal of organic matter and mineral salts.
The water regime of lakes even in the natural state is characterized by circularity, since the wet years alternate with dry. This cycle is complicated by the development of reed beds.
In the life of the reservoirs and the dynamics of their productivity there are three main phases: the phase of youth (1), maturity (2) and aging (3)’.
According to V. V. Krivenko (1978), the first phase is characterized by the beginning of the formation of reed (age 1-8 years), which cover a small area of the reservoir. This period of open water bodies and lack of organic matter is beneficial only for certain types of game animals. In the second phase of development water wetlands (reed beds age 9 – 15 years) reed beds are characterized by high mosaicity, in the reservoirthere is a multitude of floating and submerged plants. Communities in this phase give maximum number of products. In the third phase (after 12-15 years since the emergence of reed thickets) are formed continuous thickets of cane, resulting in dramatically reduced nutrient and oxygen in the water, saramsa the bottom of the reservoir.
At the same time as a consequence degrade the associations of floating and submerged plants, decreasing biomass of zooplankton and fish. The formation of dense thickets of cane degrades forage reserve for wild animals and birds and at the same time nesting conditions for wild game, which leads to lower productivity of aquatic hunting grounds.
This phase is characterized by the highest stability of ecosystems.
Received in the reservoir surface water and groundwater constantly rejuvenate – slow down or stop the natural course of aging. However, the reduction in income flow of the process of extinction of water bodies is accelerated.
This is seen in the development of biocenoses in the southern regions, water bodies of the Delta of the Kuban, Volga and other regions, where a large proportion of water withdrawn for irrigation, water supply and other needs.
In undrained or low-flowing lakes (group of lakes Meshchersky in the suburbs, lake Baraba lowland in Siberia, etc.) as a result of attenuation of biocenoses are formed continuous thickets of reed and splaviny (dead layer of sediment), degrading submerged vegetation and zooplankton, and sometimes there is a strong salinity. The result is a dramatic reduction in the number of waterfowl that occurs, for example, lake Chany in Western Siberia with 30-ies.
Stage of ageing of a reservoir may lead to complete or partial drying. If the lake bowl were left without water due to wind activity is observed, the salt and dry organic residues (sometimes fading), resulting in deepening the bed of the lake and decreases the salinity.
During the subsequent filling it with water begins a new cycle in the development of the reservoir, in the phase of youth.