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5. In average in 6 year corp field desert stern form of plant 3,9-23,5% dry stern mass. More corp field has izen-11,2-23,5%, keyruk-18,9-20,3% and chogon 16,4%. Copy field of family for culture in average in 6 years study has izen 0,7-5,8%, and chogon 2,7-2,9%.
6. According to complex economical ayaillable mark more perspective for create higher productivity of pasture agrophytoce-nosis autumn-winter period in condition submontane semideserts
Uzbekistana has subshrub — chogon and tersken and subshurbus types as izen, keyruk, polini.
In the condition of piedmont pasture in Uzbekistan was held comparative complex research in 6 types of more perspective deserted food plants out ofpigweeds family belonging to vital. According to economically variable features more perspective for creation high productive pastoral of agro plant formation, autumn and winter usage in piedmont desert in Uzbekistan.
References:
1. Amelin I. S. Improvement deserts and semideserts of pasture in Central Asia. - Samarkand. - 1981. - P. 86.
2. Zakirov K. Z. Flora and plants river pool in Zarafshan. - Tashkent. - 1975. - P. 53.
3. Shamsutdinov Z.Sh. Create long standing pasture in arid zone of Central Asia. Publishing house- "Fan". - Tashkent. - P. 175.
4. Nazarov X. T. Comparative biology, energy and economical mark some stern in subshurb and submontane semideserts in Uzbekistan. Theory and practise about arid stern productivity. Samarkand. - 1988. - P. 28.
5. Nazarov X. T. Study about types, quality and available examples of stern plants ini conditon submontane semideserts of Uzbekistan. Gene pool and selection of arid stern plants. - Tashkent. - 1989. - P. 40-46.
6. Nazarov X. T. Comparative mark productivity and stability some stern subshurbsj culture in condition submontane region Nurata. Actual question about arid stern and! asrtakhan sheep breeding productity. - Tashkent. - 1992. - P. 19-26.
DOI: http://dx.doi.org/10.20534/ESR-17-1.2-26-28
Tleumuratova Bibigul Saribaevna, PhD., in physics and mathematics, the Karakalpak branch of the Uzbekistan Academy of Sciences Deputy of the Institute of natural sciences Mambetullaeva Svetlana Mirzamuratovna, Professor, Doctor of Biology Sciences, Karakalpak State University, Uzbekistan E-mail: [email protected]
Modeling of the water-salt regime dynamics of the Aral sea and its coastal zone
Abstract: The digital model for calculation of the Aral Sea dynamics is proposed in the paper. It makes it possible to determine the following values. The solution of the coastal zone relief digital model proved to be sufficient for detection of the gulfs separating from the sea as well as limanlike areas and marsh saline soils.
Keywords: Aral Sea dynamics, ecosystem transformations, salt aerosol, degradation, mathematical modeling.
The digital model for calculation of the Aral Sea dynamics is proposed in the paper. It makes it possible to determine the following values: correlation between the sea level and the water volume, as well as the aquatory area, to calculate the location of liable to seepage salinization of coastal areas and in future the salt and dust carry-over areas. The method of minimal curvature was used in the capacity of interpolation algorithm. The solution of the coastal zone relief digital model proved to be sufficient for detection of the gulfs separating from the sea as well as limanlike areas and marsh saline soils.
Methodology of reconstruction of geomorphologic characteristics of the sea-bottom and coastal areas
The most reliable way of retrospective analysis of a coastal zone condition prognosis is the restoration of the postaqual land relief on the basis of the bathymetry. With that end in view we had designed and specified the digital model of the Aral Sea floor relief The method of the minimal curvature was used as interpolation algorithm. Thus the adjustment to the usual planar model is carried out by the method of the least squares:
jAX+BY+C=Z (X, Y)
Then the values of planar regression are subtracted from the values of initial height marks and for interpolation of distribution of these differences to the nodes of the frame the algorithm of minimal curve allowing the modified biharmonic differential equation with corresponding boundary conditions is used.
The obtained digital model of the reliefwith a pace of 1000 m per pixel has also demanded the subsequent processing — namely Furye-filtration for removal of the higher order harmonics. Application of the Furye-filtration has allowed to remove excessive, being the consequence ofinterpolation mistakes, the local minima and to approach the digital model of the Aral Sea bottom relief to the real topography. Calculation of dynamics of salt carry-over sources The Aral Sea as the closed midland reservoir and an end point of water collection possesses a number of specific physic and geographic features. It is in particular, the intensive water-salt exchange with adjoining coastal territory, high level of losses on evaporation and practically full dependence on the river water entry.
The simplified water-salt balance of the Aral Sea can be described as follows.
dW/dt = D+Dd+Du+S (W) • F (A/W)-L (W) • F_
Modeling of the water-salt regime dynamics of the Aral sea and its coastal zone
For the water balance the following ratio is used: dA/dt=Cr+Dr+Cd+Dd-L(W) x A/Wx Fm+S(W) x Col where W — total amount of water in the sea, km 3; D — a river drain (washing dumps oflakes of northern part of delta), km 3/year; Dd — a collector-drainage drain, km 3/year; Dw — natural waters, mainly unloading water horizons of a plateau Ustyurt and deposits during the autumn-winter period, km 3/year; S(W) the area of a water mirror, km 2; Fe — losses on evaporation, km 3/year; L(W) length of a gently sloping coastal line; Fmc — filtration losses along a shore, km 3/year.
Let's designate D=Dr+Dd, C= (CD+CjD^/D, h — a sea level. f— salinity, i, j, k — the moments of time (years) for the period of drying of the sea. Then the salt balance is calculated from ratio: (S (h)+S(h)Ceor(L(h.)fj +L(h)f)Fsme =2(fW(h)-fW(h))/ti-2CDj
(s(hk)+S(hj)Ceo-(L(hk)fk +L(h)f)Fme =2 (fW(h)-fW(h))/k-2C?t
from which
F= [((fW(h)-fW(h))/t-CD) (S(h)-S(h))-((fW(h)--fW(hj))/tjk-CD) (S(h)-S(h.)M(L(h)fk+L(h)jj) (S(h)--S(hj))- (L(h)f+L(h)f) (S(hk)-S(hk))], where A — total of mineral salts in Aral sea; Cr the maintenance of salts in river water; Cd — the maintenance of salts in collector-drainage drains; Ccol — intensity of wind carrying out of salts from seaside saline soils.
Time dependence of a level, volume, salinity and the water area of the Aral Sea on the river run off is an object of research and regular monitoring. We obtain the dimension value ofFf describing the salts transport from the ground waters to a day time surface of the flat beaches, equal to 3800 tons yearly per kilometer of a coastal line. It coincides with the natural data (up to 150 tons/hectare), that confirms the opportunity of relief digital models usage as the basis for modeling no equilibrium water ecosystems.
Verification of the model by the remote probing data As a result of dispersion and absorption of sunlight emission the mineral dust can play a significant role in the climatic changes, influencing the radioactive balance. Besides, salt and dust streams can influence the climate indirectly, changing the nucleation and optical characteristics in the clouds. The dust can serve as a reactionary surface, a kind of sorbent for gaseous impurity substances in the atmosphere, as well as the catalyst of photochemical reactions (Kostyuchenko, 1984). Within the bounds of the project TOMS (a spectrometer for the full mapping of ozone) the data on dispersion in the atmosphere in the ultra-violet area, caused by the aerosol presence (Ackerman, 1979; Arimoto, 2001) has been collected. Though the given technique of optical estimation of aerosol concentration in the atmosphere from the orbital device did not enable to define their chemical composition, nevertheless the source of aerosols of global value were revealed. One of such regions is the Central Asia. Two main sources of aerosol carry-over — of the Caspian and the Aral seas coasts were revealed here; in addition, in the Caspian region practically all emission took place in partly desiccated Kara-Bogaz-gol. In the Aral Sea region these sources are concentrated on the Southern and Southeastern coasts.
Short-wave and long-wave IR-channels of the satellite NOAA were used at interpretation of spaces pictures, as well as calculated vegetative index
NWI = (L - Ij/(lred + IJ Here I is the intensity of the near infra-red channel, Ired is the intensity of the red channel.
The zone of former islands and the East coast as a whole are characterized by very low projective coverings, including epheme-redes which testifies the salinity of this massif of soil.
Use of the space survey data for specification of geomor-phologic structure of the sea bottom
The effective means of the initial geomorphology determination of the desiccated bottom can be the retrospective data of remote probing of 90-2000-ies, by which it is possible to easily restore the distribution of depths in the coastal strip of the reservoir. For this purpose we used the spaces pictures received from satellites NOAA, Resource, Landsat and MODIS.
The remote probing data is the effective means of dynamics parameter correction of the aquatory area and the coastal line position calculated by the bathymetry.
The pictures of NOAA, despite of their insufficient spatial resolution (1 kilometer per pixel), allow to estimate the depths distribution practically on all the water area of the Aral Sea, except the deepest water sites of the Western part. At the same time the set ofMODIS pictures enables to average distribution ofphototone with the purpose ofexception of undesirable influence of meteorological factors and aerosol streams.
As the initial data set on the regression, subject to specification, the 1:100,000 scale bathymetrical map ofAral Sea digitized and transferred in a uniform projection with the space pictures was chosen. For elimination of structure characteristics of the back surface, not described by generalized isobaths of the given map, the spatial averaging of the image intensity in the direction of a descending bottom and the spline — interpolation was carried out. Then according to the depths marks and the intensity set the variogramme was built which minimized a geospatial mistakes.
The heterogeneity revealed by us in dependence depth — intensity can be explained, first of all, by non-uniform distribution of a phytoplankton, constant presence of a dust haze and also a natural background noise of the touch device. The digital relief model of a newly drained bottom received on a variogramme, giving enough information for revealing of salt accumulation sites, is a starting point for the subsequent existential analysis of a postaqual land condition dynamics Alternative method of bathymetry restoration according to remote probe of a shallow coastal zone is use of Markovian field model with the latent parameters. In this variant natural correlations between true depth and optical density of the image are allocated on a background of steady fluctuations of water thickness optical parameters and a bottom, the silt weights caused by moving in a strip of a surf which intensity directly depends on characteristics of a ground surface, its structure and morphology:
Dt=f C • Fj • M(Fj) • hj2)
where: i, j — coordinates of a raster point on a picture from space;
t — time of a space survey;
D..t — density of image phototone;
h.. — depth;
F ,tt — a turbidity of water;
C.tt — optical density of a sea-bottom surface;
M — median average on nearby points of settlement area, the size of averaging area is determined by depth h
f — the empirical function close to linear.
As the one-seasonal set of pictures from spaces of the average resolution is used, it is possible to neglect washing out of a bottom under influence of coastal currents. From obvious preconditions smaller time dependence of optical density in comparison with a turbidity of water is postulated:
(j^lA) << (|Cijt+1-Cijt|/Tt)
where — the settlement period (one year); Tt — the period of time between the moments of data remote probe acquisition.
The resolution of coastal strip relief digital model appears sufficient for revealing gulfs separated from the sea, like estuary sites
and marsh saline soils. Use of coastal strip digital model enables to estimate volumes of a salt storage on postaqual land and spatial distribution of water-soluble salts deposits (Statov et.al., 2004). Results of model verification with the data ofremote probe and KazNIGMI's data are given below in graphic performance Comparison of designed Aral Sea water area with use of geomorphologic model with the remote probing data (satellites MODIS and AQUA) specify high quality of model. Also the comparison design volume of the sea with calculation by standard KazNIGMI methodology was carried out. It
was established, that insignificant differences of the geomorphologic model created on the basis ofbarely bathymetrical data, are completely removed by correction according to remote probing data.
The geomorphologic model of the Aral Sea developed by us made it possible not only to determine the coastal line position, the area and volume based on the data about the sea level but also to estimate the location of constricted marsh saline soils, low flat beaches, negative forms of a relief and other potential sources of chloride and sulphatic aerosols emission.
References:
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2. Arimoto R. Eolian dust and climate: Relationships to sources, tropospheric chemistry, transport and deposition//Earth Sci. Rev. -2001. - V. 54, - 29-42.
3. Kostyuchenko V. P. Salinity oflands of a drained bottom ofAral Sea as the precondition for Aeolian carry-over of salty dust//Problems of desert development. - 1984. - No 2. - P. 27-33.
4. Statov V. A., Tleumuratova B. S., Kapustin G. A., Ressl R. Geomorphologic analysis of a coastal zone of the Aral Sea with the use of the space survey data//Bulletin KKB of AS os RUz,. - 2004. - No 3-4.
