PhD Ospanova Zh.Kh¹, Sc.D., professor M.R. Khanturin¹ ,

Sc.D., professor Isaeva A.U.²

¹Eurasian National University named after L.N.Gumilev,

Astana, Republic of Kazakhstan,

²Southern Kazakhstan state university named after M.Auezov,

Shymkent city, Republic of Kazakhstan

Natural waters ecological status of Southern Kazakhstan region

Natural factors determining the kind composition of hydrobionts are hydrological, hydrothermal and hydrochemical parameters of the watercourse, which change substantially with decreasing geographic level, towards of which all oblast (regional) rivers flow. In addition, in the same direction is increasing the level of anthropogenic impact on water sources associated with the surface waste water inflow from human settlements, agricultural landscapes and enterprise industrial areas. The combination of these factors significantly affects the formation of communities of aquatic vegetation. In this connection, hydrochemical researches have been carried out for studying influence of water pollution degree on zooplankton species diversity. For this purpose the chemical analysis of waters of all investigated rivers, in sites before and after technogenic sources has been performed. The basic types of pollutants and seasonal dynamics of variation of their content in water were defined.

It has been established, that the basic sources of pollution are unorganized dump of garbage and sewage from settlements, superficial drains from territory of agricultural objects and sewage of the industrial enterprises, and polluting substances - nitrates, nitrites, mineral oil, sulfates, chlorides, ions of magnesium, copper and some heavy metals which mid-annual concentration exceeds norm in 1.4 – 5.8 maximum permissible concentration MPC. Thus, the nature of polluting substances and impurity degree of the water environment of the investigated reservoirs are in strict dependence on influence specified above sources of pollution. For example, a major source of water pollution in the river Badam by ions of heavy metals are wastewaters and underground waters of industrial territory of JSC "Yuzhpolimetall" (UPM). Waters of the rivers Koshkar-Ata and Mashat become soiled by organic substances through municipal and superficial sewage of inhabited quarters and industrial objects. As receipt process of pollutants in the rivers carries a seasonal nature connected with meteorological conditions of seasons, the concentration of polluting substances in water varies essentially. Surface seasonal streams, formed as a result of heavy rainfall and snow thawing in autumn and spring months, contribute to the flow in the rivers salvo doses of pollutants. For this reason, the maximum indicators of impurity have on spring and autumn, and minimum for summer and winter months. The level of impurity of the river Arys water increases in process of water acceptance of its main tributaries. In process of tributaries number increase, running into the river, quantitative and qualitative indicators of water pollution alter, which also vary from season to season. The concentration of principal types of pollutants defined the water pollution index (WPI), based on that a ranked list of the investigated reservoirs to quality classes is made. The analysis of the received data has shown that to a category of very pure (WPI – 0.24 - 0.25 ± 0.01, 1 class of quality) 3 rivers of the area concern only. And among other investigated 26 rivers and water basins to a category of pure (WPI – 0.5-1.0 ± 0.02, the second class of quality) concern 11 ones, to moderately polluted-8 rivers (WPI – 1.78 - 2.41±0.03. 3 class of quality), to polluted-1 river (WPI – 3.8 ± 0.02. 4 class of quality), to dirty-2 rivers (WPI – 5.01 - 5.01 ± 0.14. 5 class of quality), to very dirty-1 river (WPI – 8.9 ± 0.2. 6 class of quality) and 1 river - to extremely dirty (WPI–12.6 ± 0.61, 7 class of quality). By the analysis of researches results revealed that concerning to 1 and 2 quality classes of waters reservoirs are located in foothill areas, out of industrial zones of the area which are characterized by the small extent (8-10 km) and low anthropogenic impact.

These rivers are characterized by a narrow channel with a rocky bottom and a rapid current. The water temperature in winter and summer months fluctuates in limits from 0-2⁰ С till 12-14⁰ С accordingly. The main pollutants of the aquatic environment are ions of magnesium and sulphates the concentration of which does not exceed value of maximum permissible concentration (MPC). The insignificant content of organic pollutants and the lowered water temperature limit the rates of biochemical processes, as evidenced by indicators BOD₅ - from 0.6 ± 0.03 mg O₂/dm³ to 1.05 ± 0.04 mg O₂/dm³. These conditions of aquatic environment are the natural selective factor for zooplankton community formation, adapted to the conditions of not polluted aquatic environment with a relatively low temperature.

Reservoirs of subsequent classes of quality, proceeding through many settlements and industrial zones, are exposed to pollution by mineral and organic substances. For instance, such rivers of a spring source as Togus and Lengersaj, have a length of not more than 12 km which lies through large settlements like Togus and Lenger. Their water resources are limited and, for this reason, seasonal fluctuation is reflected very strongly. The water temperature in winter and summer months ranges from 6-8 till 20-25⁰ С accordingly. Household sewage from the population which contains organic substances in a considerable quantity is the main source of pollution. During warmer months water environment of these reservoirs is characterised by intensive rates of a course of biochemical processes. Sharply increases the water content of total nitrogen and other nutrients and a deficiency of oxygen dissolved in water (BOD₅ - from 34.6±1.03 mg O₂/dm³ to 61.05 ± 0.04 mg O₂/dm³) increases water saprobity. Parameters of water environment characteristics established earlier contribute formation of zooplankton, consisting only from kinds resistant against specified conditions of inhabitancy. Contrary, rivers Mashat and Bogen are characterised to have a greater way by extent before merge to the river Arys. Throughout this way there is a change of hydrothermal, hydrochemical and saprobiological characteristics of the aquatic environment. These rivers at the sources, in foothills of Tjulkubassky and Bajdibeksky areas, under these characteristics correspond to the first class of quality as the rivers of glacier. However, in process of lowering of geographical level, the temperature and level of their waters impurity raises. In the case of the river Mashat, this is due to the flow of rivers through such towns as Mashat, Kershetas and to location on its banks for more than 30 sanatoriums and holiday camps. On this interval there is a pollution of the river by mineral and organic substances which leads to its sharp decrease of hydrochemical and saprobiological characteristics. The level of water mineralization increases of 4.3 times or more. In the river estuary before merging with the river Arys WPI makes 2.40 that corresponds to the third class of waters quality, moderately polluted. The basic characteristics change of the aquatic environment of the river Bogen occurs similarly to indicators of the river Mashat. Due to a rapid current and average temperature (4-5⁰ С in the winter and 18-20⁰ С in the summer) aquatic environments of these rivers do not have a high rate of biochemical processes, as evidenced by indicators BOD₅ – 1.6 ± 0.08 mg O₂/dm³ in winter and 2.15 ± 0.41 mg O₂/dm³ in summer months.  Above established parameters of the water environment create new conditions for zooplankton community that structure will depend on the degree of adaptability and competitiveness of its constituent kinds.

The main extent of the river Badam is on the plain territories of the oblast (region).  In winter and summer months the water temperature in the river varies from 3-4 to 16⁰ C-18⁰ C, accordingly. Sharp increase of water mineralization level occurs on a site in the extent about 20 km which falls within the industrial zone of Shymkent city. The main source of waters pollution of the river Badam are surface wastewaters and underground waters from industrial territory of JSC "UPM" which has hydraulic interrelation with the river. Except ions of magnesium, calcium and iron ions of such heavy metals as lead and the cadmium also get to river water, the concentration of which, seasonally exceed in the MAC indicators 2.1 - 3.5 times. Results of chemical analyses of the waters held in 2005-2008 showed that the content of heavy metals ions around a gauging station №1 does not exceed the limit values. In this area, the main pollutants of river waters are nitrates and nitrites (11.5±1.1 and 0.034±0.001 mg/l N) which come with waters of the rivers Togus and Lengersaj. Pollution of river water by ions of lead, cadmium and zinc occurs in the interval of the river which is located on territory of an industrial zone of JSC "UPM". As shown in Figures 143 and 144 in the gauging station №2 pollutant concentrations exceed the MAC - on sulfates 3.5-fold; by nitrite - 2.2; of magnesium - 2.1, -3.5, on lead, the cadmium - 2.8 and 3.4 for zinc. In the area of gauging station №3 somewhat rises the level of water impurity of the river organic compounds which come along with river Koshkar-Ata. However indicators of BOD5 in this segment of the river do not exceed 2.55 – 3.22 ± 0.12 mg O₂/dm³. Thus, in the estuary water quality meets Class 4, the polluted waters (WPI equal to 3.80 ± 0.01).

The river Koshkar-Ata concerns to the fifth class of waters quality and is characterised as a dirty one. Sources of pollution of the river waters are public drains of a private sector. The water environment of the river is polluted by various organic compounds, which are dominated by nitrites, nitrates, oil and other organic contaminants. In addition chlorides, sulfates and mineral salts of copper, zinc, magnesium and iron concentrations are found which are slightly higher than the limit values. The high content of organic chemistry in the conditions of the water environment temperature rise promotes strengthening of the biochemical processes connected with their recycling. In these conditions, the intensification of the absorption of oxygen dissolved in water and development of aquatic organisms that severely degrade the performance saprobiological waters.

According to its geographical location and level of technogenic impact is a unique model river watercourse. It originates from large underground water sources in the city centre of Shymkent city and 12 km runs into the river Badam. Hydrological characteristics of a watercourse are uniform on all extent of the river. A channel in width of 5-12 meters with a sandy-silty bottom, flat coasts, a moderated current. Water temperature at sources within a year fluctuates in the range 8 - 14±1.3⁰ С. However, on the middle and latter parts of the river it makes 5 – 20 ± 2.2⁰ С and 3 – 25 ± 1.1⁰ С accordingly. As the distance from the source of the river level rises technogenic impact sharply increses, accordingly hydrochemical indicators of its waters that entails also changes of specific structure of zooplankton community and algoflora.

The dependence of a specific variety of zooplankton on hydrochemical indicators of reservoirs is established.