target and necessity to implement targeted activities

2.1.2 Climate and atmospheric air

The climate of this territory is extremely continental with low precipitation and high summer and low winter temperatures. All these as well as low relative air humidity and often winds increase moisture evaporation from soil layer and promote soil salinization. Low winter temperatures cause upper soil layer freezing that deteriorates its hydrophysical properties and hampers processing and washing.

Average annual temperature fluctuates in the range of 14,4-16,4⁰С, average monthly temperature of the hottest month July makes up 28,4-29,4⁰С, in the daytime the maximum air temperature reaches 43,4-46,0 ⁰С, while the minimum one during the strong fall in winter (December) temperature drops to –15,2-24,9 ⁰С, with monthly average of –4,8-5,5⁰С. Average daily temperatures: maximum ones are in late July and early August, minimum – in January-December.

Average annual temperature of soil fluctuates in the range of 19,0-19,5⁰С, maximum average annual temperature being 37,6-37,8⁰С, minimum - 7,5-8,2⁰С. Soil surface temperature in summertime is very high and absolute maxima this time of the year reach 70-71⁰С. In wintertime it, however, drops to –18-20⁰С, annual amplitude fluctuations of soil temperature being 45,2-49,2⁰С.

Average annual amount of precipitations falling in Buharsk and Karakul oases makes up 208,6 mm and 162,0 mm, correspondingly, out of which 114,9 and 76,8 mm, respectively, fall at night and 93,7 and 85,2 mm, correspondingly - in the daytime. According to “Buhara” and “Karakul” weather stations maximum amount of precipitations during two days make up 23,1 and 18,8 mm or 66,6 and 39,4% of the average monthly norm respectively. Maximum precipitations occur in spring (42,5-52,6%), 30,7-57,1% fall in winter, 1,4-16,1% in autumn, while summer is practically rainless (0,5-3,1%).

Average snow cover is 4-5 cm in depth, as a rule it is loose and unstable and often melts, while in sever winters it can become dense, which causes soil freezing up to 50-60 cm.

Average annual relative air humidity is marked by wide fluctuations in the range of 52-55% at “Karakul” up to 59-61% at “Buhara” weather station. Winter months are characterized by the highest relative air humidity at the level of 74-85% and summer months by the lowest one of 33-45%.

Little precipitations, high air temperature, intensive solar radiation, high relative air humidity cause strong evaporation in the oases.

Annual evaporation makes up 1750-2040 mm. Over 80% of moisture evaporates airing warm six months. Moisture deficit makes up 1580-1770 mm. In summertime the amount of evaporating moisture exceeds atmospheric precipitations 40-45 times approximately, which, in its turn, promotes intensive salinization of soil.

According to the wind rose by Karakul weather station northern winds most evidently prevail in summer months, wind direction is wintertime is roughly the same, excluding south-western winds.

As to the air pollution potential (set of meteorological factors stipulating the level of possible air pollution from the sources in this geographic area), Khauzak and Shady territory - Kyzyl Kum desert – is situated in the area of moderate air pollution potential.

Environmental audit was held on the territory of contract sites in late 2004 – early 2005.

Sites atmospheric air samples were selected on 22 sampling stations. In some spots high maximum occasional dust content was detected, which can be explained by Kyzyl Kum desert (with Khauzak and Shady located on its territory) belonging to the nature resources of atmosphere dustiness. 3-4-fold increase in MPC level of atmospheric air dustiness is observed in the southern and, in particular, in the south-eastern part of the examined territory. Maximum dust concentrations have been fixed at the rate of 2,778 mg/m³ (5,6 MPC), minimum ones - 0,429 mg/m³ (0,9 MPC).

In all samples collected on the sites methane was found, though its concentration does not exceed approximately safe level of impact (ASLI – 50 mg/m³). Maximum methane concentration in the samples is 2,743 mg/m³. Carbons С₂-С₆ were not found in the samples.

Oxygen content in all analyzed samples was a little lower as compared with clean air. No carbon dioxide was found in samples.

High concentrations of the following components have been observed:

nitrogen dioxide – from 1,29 MPC to 7,94 MPC;

nitrogen oxide – from 1,12 MPC to 2,35 MPC;

ammonia – from 1,07 MPC to 40,835 MPC;

xylol – from 4,22 MPC to 5,46 MPC;

toluol – from 2,76 MPC to 4,17 MPC.

As to the rest examined components (carbon oxide, sulfur dioxide, benzol) no MPC exceeding was detected. Maximum concentrations in samples made up:

carbon oxide – 2,3 mg/m³ or 0,46 MPC;

sulfur dioxide – 0,488 mg/m³ or 0,98 MPC;

benzol – 0,477 mg/m³ or 0,32 MPC;

2.1.3 Surface and subsurface water

Dengizkul lake is situated in Alat district of Buhara region and originates from a spring. Eastern part Buhara-Hivinsk area is a downfold zone with regard to Central Kyzylkum. Dengizkul depression (the former lake) is one of such downfolds. Nowadays this depression represents a large saliniferous basin for drainage water collection; it’s total area is 267 km² and the capacity is 2723,4х10⁶ m³.

At the present moment lake Dengizkul situated in the lower reach of the Zaravshan river in the deepest area of a big tectonic depression flows into the main arm of the Zaravshan river – Taikir, as well as several waste and drainage water channels. Dengizkul lake is a closed one.

The area and depth of lake change constantly: in high-water years the lake surface reached 110-120 thous.ha with water volume of 3-3,5 bln. m3 and inmost depth of 25-30 m. At the present moment its area is 50-60 thous.ha. The water is very salty; its bottom has a 4-6 cm of salt cover. According to the data of the Main office of water economy of the Republic of Uzbekistan the estimated water level in lake Dengizkul makes up 184,2 – 184,4 m.

Only 150-230 mln. m³ of water flew into the lake in 1993-2003 instead of 480-550 mln. m³ of water inflow in the years 1985-90. This amount of inflow water doesn’t cover evaporation losses and the water volume decreased by 60%. As a result, the lake area reduced almost twofold and stripped a salted lakeshore line. Water mineralization increased approximately 5-8-fold, including: 8-fold in chlorides, 26-fold in sulphates, 7-fold in nitrates, 6-fold in biological oxygen demand (BOD) content.

Rush and bush covering of the lake area for 25-30% is considered to be favourable for fish reproduction and growth. In spring and autumn birds flyways go through the lake, some of the birds stay for the winter. The lake is an ornithological reserve and is included into the International list of objects of Ramsar Convention on the Wetlands of International Importance especially as wildlife habitat and has a universal importance.

Lake Dengizkul is the largest wintering area of swimming birds (over 50 species) in Uzbekistan, over one hundred species of avifauna use the lake as a flyway in spring and autumn.

In accordance with the art.5 of the Republic of Uzbekistan Act On Specially Protected Natural Areas, “Dengizkul” special nature reserve refers to the territory for natural objects and complexes conservation, reproduction and restoration. It was created by Uzbekistan Government regulation No 530 in 1973 and then prolongated by Buhara Regional Executive Committee resolution (No 157/11 as of 26.09.90). This special nature reserve is used to protect wildlife and its habitat and conduct scientific researches. Hunting, fishing and plants gathering are prohibited.

According to the regulation No 174 as of 07.04.92 by the Cabinet of Ministers of the Republic of Uzbekistan “On the approval of regulation on the water-protective zones of water reservoirs and other water bodies, rivers and main channels and collectors as well as sources of drinking and domestic water and medicinal and health-improving water in the Republic of Uzbekistan” a sanitary conservation zone of 500 m was established around the lake within the distance of which no disposal sites, industrial waste dumps, chemicals and etc. are allowed.

Civil, dredging and blasting works, mining operations, laying of pipes and other communications as well as other works are performed only upon agreement with Nature Conservation Authorities.

During the Environmental audit conducted at Khauzak and Shady sample analyses were made separately for three groups: water collected from open water reservoirs, ground water and drinking water. In total 22 water samples were collected on the sites, including 10 samples from surface water reservoirs, 6 ground water samples and 6 drinking water samples.

The analyses results showed the following:

Sulfate and magnesium water predominate in Lake Dengizkul, its mineralization being 20-25 g/l, which manifold exceeds the set MPC level. As the distance of the discharge collector inflow point to the lake increases, water mineralization goes up and exceeds 25 g/l at a small distance from the discharge collector, i.e. Lake Dengizkul belongs actually to the category of saltish water. Though biological and chemical oxygen demands exceed allowable MPC level on the whole lake surface, but as the distance of the discharge collector inflow point to the lake increases, their values grow 3 and 15-fold, respectively. BOD and COD are maximum in the south-eastern shore of Dengizkul lake (up to 70 and 50 MPC, correspondingly).

The average amount of dissolved oxygen in the lake makes up 0,5 mg3/l, which is 8 times lower than the minimum limit set for the fishery bodies of the 2^nd category. At the same time the amount of dissolved air in the discharge collector water corresponds to the value set for the fishery bodies of the 1^st category.

The amount of phenol in Lake Dengizkul goes up as the distance of the discharge collector inflow point increases and its concentration exceeds the set MPC in the middle of the lake water surface, its maximum concentrations being detected on the north-eastern lakeshore of Dengizkul.

Comparison of phenol allocation in Dengizkul water and atmospheric air testifies to the fact that the increase in phenol concentration as the distance to the north-eastern lakeshore decreases (approximately in the mining allotment area located in the middle of the lake) is logical.

Benzol and oil products in the ground water have been detected at all sampling stations, however, their concentrations do not exceed the set MPC.

All over the ground water suspended solids and dry residue exceed the allowed MPC 25 times (from 25 to 48 MPC), total water mineralization – 27,5 times (from 9,18 to 47,8 MPC), BOD and COD (from 4,29 to 41,2 MPC), BOD₅(from 3,07 to 29,4 MPC). Ammonium, nitrites and carbonates ions haven’t been found in the ground water. High concentration of Xylol - from 3,4 to 105 MPC was detected there.

Ammonium, cadmium, copper, nickel, lead, iron and zink were found in the drinking water but their concentrations are considerably lower that the allowed MPC. Not all these substances exceeded MPC: cadmium (from 3 to 10 MPC), aluminium (2,3 times more than MPC) with practically no concentrations of it in artesian wells. Pesticides in the drinking water were not found either. Benzol and oil products were detected but their concentrations in the drinking water was considerably lower than the MPC. Water from artesian wells used on the site as drinking water is mineralized, its mineralization exceeding MPC 6,6-7,2 times. According to sanitary and bacteriological characteristics water from only one artesian well meets the requirements of the set norms.

Microorganisms capable to reproduce due to oxidation of oil hydrocarbons are found in all water samples (excluding discharge water collector) and bottom silts. In most samples their number is in the range of 10³-10⁴ cells per 1 ml.

According to subsurface water difference in age and lithologic deposits on the considered territory, the following hydrogeological elements can be distinguished: aquiferous, locally aquiferous, water permeable, but waterless and water-proof complexes, crack aquiferous zones.

The examined plot of planned construction belongs itself to the Buhara-Karshinsk artesian basin. According to the surveys quaternary deposits aquifer system is the closest to the ground surface. Groundwater depth is 10 meters and more.

Subsurface water mineralization is over 3g/l. Water type changes from hydrocarbonate calcium to sulphate chloride water. Water is salty and can be used only as utility water; subsurface water is fed through filtration of discharged surface water from the main collector and partly by means of precipitants infiltration.

Subsurface water are opened for geological engineering survey at the depth of 0,6-2,1m in highway laying area near the frontier post and on the territories adjacent to lake Dengizkul (bordering on Turkmenistan).

2.1.4 Soils

Soil cover consists mainly of grey-brown poor-developed, desert sand soils. These are automorphous soils of the desert zone, referring to relatively postmature surfaces. As to the mechanical makeup, soils and subsoils are basically light granulated: loamy sand, sand, more rarely loam. Medium and heavy loam layers are also found. Fine dust particles (0,1-0,05 mm) prevail among the soil fractions. These soils contain a small amount of humus (0,4-0,8%), nitrogen, phosphor and potassium. Their formation occurs at the close ground water level to the ground surface (1,5-2m).

All soils and subsoils of the site subject to salinization, the degree of which varies from slight to strong, this being stipulated by the macro-and micro relief of the terrain, hydrogeological conditions and subsoils mechanical content. As to the chemical nature of salinization, the soils and subsoils are mostly sulphate-chloride, more rearly chloride-sulphate.

Soils (subsoils) sampling during the environmental audit at Khauzak and Shady, conducted at 22 sampling stations (0,3-6 m in depth) and 6 sampling stations near the formerly drilled wellheads showed the following:

At some spots of Khauzak site oil products content in soils (sampling depth up to 0,3 m) 5-6-fold exceeds their concentration in the subsoils (sampling depth up to 6 m), which can be explained by fraction composition of the soil, dominated by fine dust particles preventing from oil products “penetration” in the soil depth. Nowadays soils pollution caused by anthropogenic activities, for instance, well drilling, is therefore observed mainly in the surface layer.

Out of organic matters in the bottom silts, xylol, phenol as well as synthetic surfactants have been found. Benzpyrene is the main representative of multiring aromatic hydrocarbons detected in bottom silts. However, its content in bottom silt samples is low and it brings no carcinogenic risk to the environment.

Khauzak and Shady are distinguished by high hydrocarbon content in soil and bottom silts, with maximum number of oil- and phenol-oxidizing bacteria found in Khauzak as a whole and in single spots of Shady (near the north-eastern shore of Lake Dengizkul), which, in turn, correlates with phenol allocation in the atmospheric air, water and soil.

The number of microorganisms in the single samples of the soil and bottom silts of the considered territory reaches 10⁵-10⁶ of cells per 1 g.

As to the subsoils, according to the engineering-geological researches and on the basis of physical and mechanical properties of subsoils, three geotechnical elements (GTE) have been singled out. The most details description of subsoils parameters, with a view to implementation of industrial construction upon the materials of engineering-geological researches, was given in the EIS.

2.1.5 Flora and Fauna

The nature of soils and their wetting degree determines vegetation cover development.

Vegetation in this region is represented mainly by mixed herbs and shrubs on the sand.

The following plant associations have been found out: ephemer-wormwood and amber-black brown. The prevailing plants are: alhagi (camel's-thorn), asparagus, calligonum, Salsola Richteri and other species of saltworts (Salsola arbuscula, Salsola gemmascens). Saxaul, several species of “suzerain”, sandhill wattle, aristida (pictures 8-11). Takyric soils are characterized by different types of wormwood: with psammophyte shrubs, ephemer and Calligonum. On saline lands saltwort-ephemer plants are widespread.

Large areas of channel- and lakeshores are covered with tamarisk brushwood with some alhagi and saltworts. Poplars (P. pruinosa and P.diversifolia) and horsetail (Equisetum ramosissimum) grow along the water basins. Reed, blackamoor, meakin, bladderwort and etc. grow in the water basins.

The flora is represented by 13 endemic species and 3 red-listed species, 14 rare and 19 scanty species on the whole.

Picture 3 - Aristida	Picture 4 - Saltwort

Picture 5 – Saltwort	Picture 6 – White saxaul

To the present moment the soil is covered with vegetation for 30%. Plants have morphological changes but they are minor (mainly necroses). Vegetation is very thin; there are spots of its full absence.

The Fauna is represented by 27 species of mammals, 17 species of reptiles, over 160 species of birds, out of which 3 species of mammals, 24 species of birds, 2 species of reptiles and 7 species of arthropoda are red-listed.

The lesser white-toothed shrew and piebald shrew are widespread on the territory considered. They are active mainly at night in autumn, sometimes in the daytime. The species population varies.

The long-eared hedgehog is widespread on the whole territory. It lives in holes and eats different food: ground beetle, scarabs, acridoid grasshoppers, butterfly caterpillars, beetles and etc. It also eats vertebrates (lizards, small birds) and plants. The Brandt's hedgehog is less common than the long-eared hedgehog and lives in the same conditions as the long-eared hedgehog. Red-listed. The European free-tailed bat is a red-listed vulnerable rare species of bat.

The tolai hare, long-clawed ground squirrel, Severtzov's Jerboa, southern jird, Libyan jird, giant day jird are the typical faunal forms of these region.

Fox is a bit smaller and lighter here than in other places.

The Caffre cat living in some habitats is relatively small by size. Marbled polecat is a numerically insignificant species. Steppe polecat is a very rare species on this territory.

The goitered gazelle used to be wide-spread in the desert of the considered territory. Intensive desert land development and animal breeding as well as poaching caused rarity of the goitered gazelle as species and it was red-listed.

Researches of the avifauna showed that there are over 160 species of birds inhabiting the territory, about 40 species are nestling there. 24 species are red-listed. A lot of bird species visit the area during seasonal migrations. Typical inhabitants: sky lark, fringillidae family, chats, sand grouses, small predatory birds, besides the lake is also inhabited by aquatic and semi-aquatic birds. To protect the birds an ornithological reserve was created on the territory of Lake Dengizkul in 1973 and exists till nowadays. The lake is inscribed into Ramsar Convention as a wetland having international importance in the quality of aquatic bird’s habitat.

The birds of pray are represented by a great many of falcon and goshawk species.

Besides, many other species of birds are found on the sites: corvidae family, coraciiformes, starlings, fringillidae family, sky larks, wagtails, warblers, the Turdinae and other.

The territory of the area considered is inhabited by many reptile species, which, due to their biology, can be rare and numerous: toad agama, sunwatcher, plate-tailed gecko, racerunner, Eremias lineolata, Eremias intremedia, Eremias grammica, Coluber karelini, corn snake (Elaphe guttata), Psammophis lineolatus and etc.

The steppe tortoise inhabits loess-like, sandy-loam and sandy areas of the plain and foothills. A lot of tortoises used to be found everywhere.

The steppe agama is a widespread common species on this territory.

The toad agama is a common numerous species.

The desert monitor is a scanty red-listed species.

The Tartar sand boa inhabits sandy areas fixed and semi-fixed sands.

The Central Asia cobra was sometimes found. Red-listed.

The Saw-scaled viper was also found.

From the amphibia the green toad and lake frog inhabits the area considered.

The ichthyofauna of lake Dengizkul is basically known for its commercial fish species: European carp, pikeperch, zherekh, fresh-water catfish, shemaya, carpbream and snakehead. There are other fishes in the lake; they don’t have any commercial value but constitute an integral part of the water body ichthyofauna and are particular valuable in biological diversity.

To determine physical and chemical conditions impact of the territory NE on the physiological state of living organisms and vegetation within the Environmental audit, ecotoxicological researches on microelements and pesticides accumulation in local plants tissue were pursued.

Their results showed that physical and chemical conditions of the sites Khauzak and Shady are, on the whole, unfavorable and produce a negative effect on the physiological state of flora and, subsequently, fauna, though it is local.

Liver dysmorphology, hepatocyte necrobiosis and dissection of muscle fibres (myopathy) is mainly true for the rodents eating tree roots than those eating fruit, which have comparatively less manifested functional disorders only in liver tissue.

Liver dysmorphology, зфкешфд hepatocyte necrobiosis and dissection of muscle fibres (myopathy) is mainly true for herbivorous fishes. No visible histopathological changes in predatory fish have been detected in any of the examined tissues (muscles, liver, gonads).

The above noted negative impact on flora and fauna is local.

2.1.6 Landscape

According to the ecological map of the Republic of Uzbekistan the ecological situation tensity is moderate in this region, i.e. no big anthropological impact have been made on the landscape.

The construction site is defined as a hilly sand plains lanscape with wormwoods and kandymnik on desert sand soils, barchan sands spots with pioneer-psammophyte aggregations.

Cultural and historical monuments haven’t been recorded in Khauzak and Shady area.

Economic land development and construction and operation of gas producing and gas-transport facilities have increased the anthropogenic pressure to a certain extent.

However, negative impact on the flora and the fauna as well as landscape is, on the whole, weak due to the dispersal of industrial facilities.

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