Water-salt Regime Research Articles

Natural conditions of Varandey coastal tundra. Anthropogenic transformation of natural landscapes

The author aims to characterize natural conditions in the coastal area of the Barents Sea, from the settlement of Varandey to the Perevoznoye field. The research covered an area of 20 km2, 40 km long. An integrated climatic characteristic of the studied area is given, including the direction and speed of natural processes forming its shape, cryogenic processes, flora and fauna conditions, soil cover formation. The geomorphological, geological, and hydrological features of the area are outlined. The heterogeneity of the water–salt regime of the coastal area, typical of the northern seas of the Arctic, including the Barents Sea, is noted. In the laidas, the prevalence of accumulation of easily soluble salts over their removal is established, which allows the soils to be distinguished in terms of their salinity. Here, halophytic species are identified. The vegetation cover of the studied area is characterized according to the habitat of flora representatives. The research identified 100 species of vascular plants, 51 species of lichens, and 65 species of mosses. A soil survey found 27 soil varieties, which form the structure of the soil cover; their morphological and physicochemical characterization are given. The data obtained during field studies and remote sensing data were used to determine the structure of landscapes to the level of terrain types and units, as well as to propose their description. Their ecological and geochemical typification is carried out. The fauna composition was assessed based on state registration data and open sources; field observations with reference to biotopes were used. The dynamics of fauna population on the Barents Sea coast was assessed retrospectively. Field survey and remote sensing data made it possible to identify areas with anthropogenic disturbance of tundra landscapes. A typification of the identified anthropogenic disturbances of the natural environment and their areas within the survey area is proposed. The data obtained can be used as signs when assessing the state of natural environments in the coastal part of the northern seas of the Arctic, similar in terms of natural and climatic conditions.

Influence of Natural Water Hydrochemistry in the Vakhsh River Basin on the Water–Salt Regime of the Irrigated Agricultural Land

Influence of Natural Water Hydrochemistry in the Vakhsh River Basin on the Water–Salt Regime of the Irrigated Agricultural Land

The Effect of Natural and Anthropogenic Factors on the Seasonal Ecohydrological Dynamics of the Eastern Basin of the Hypersaline Sakskoe Lake, the Republic of Crimea

Crimean salt lakes have a high resource potential used in various types of human activity, i.e., balneology, chemical industry, and therapy; now, they are attractive tourist sites. A combination of biotic and abiotic factors creates specific conditions for the development and functioning of biota and the formation of unique ionic composition of brine and bottom sediments, which are used in balneology and the production of spa-products. Sakskoe Lake is among the largest coastal salt lakes of Crimea, located on the southwestern coast of the Black Sea. The effect of climate conditions and biota caused the formation of a specific ecosystem in the lake, which has a peculiar ionic composition of brine, changing within the year, and a brine shrimp population. The concentrations of cations and anions in the brine increased in summer because of active evaporation and decreased in winter and spring because of dilution of atmospheric precipitation and snowmelt water. The dynamics of the brine population also showed characteristic seasonal features: the life cycle begins in April, the maximal number of various life stages is recorded in May–June, and the end, in November–December. The artificial regulation of the water–salt regime of the water body through addition of seawater in summer contributed to maintaining optimal conditions, thus ensuring a high vital activity of the biota. The obtained data can reflect the seasonal dynamics of processes in the salt lake, governed by climatic, seasonal, and anthropogenic factors.

Подходы к снижению негативных последствий использования слабо- и маломинерализованных вод в орошаемом земледелии

Purpose: to identify the most suitable measures aimed at achieving the rational use of brackish and low-mineralized water resources for the Republic of Crimea, based on an analysis of foreign and domestic experience in ensuring the environmental safety of irrigation with limitedly suitable waters. Discussion: during the study, a review of foreign and domestic developments to reduce (prevent) the negative impact of irrigation with limitedly suitable water resources on soil and crops and an analysis of approaches, implemented in the Crimean region, aimed at ensuring environmental safety of using brackish and low-mineralized waters in irrigated agriculture was carried out. It has been found that the main technological solutions aimed at reducing the negative impact of using limitedly suitable water in agriculture include: determining the maximum permissible mineralization of irrigation water from an ecological and economic point of view, reducing irrigation rates, selecting effective agronomic practices, justification the irrigation method and preliminary water treatment, carrying out washing with fresh water, forecasting and modeling of the water-salt regime. The first four approaches are mainly used in the Republic of Crimea. In general, their use makes it possible to prevent a significant decrease in crop yields and the intensive development of soil degradation processes. Conclusions: to ensure the environmental safety of irrigation with limitedly suitable waters, approaches that include the use of water resources with mineralization up to 3 g/l in combination with water-saving irrigation methods, reduction of irrigation rates and the application of chemical ameliorants, it is advisable to supplement with annual water quality and soil condition monitoring, as well as to provide for forecasting the salt regime of the fertile layer in the future.

The influence of fertilisation on the water-salt regime in the conditions of the Mugan-Salyan massif, Azerbaijan

The article presents research data on the amount of salts in the irrigated soils of the Mughan-Salyan massif, their composition, water-salt regime, and their forecast. It was found that the soils on the territory of the massif were saline to varying degrees. In general, the area of non-saline soils in the massif is 125,650 ha, mildly – 272,070 ha, moderately – 210,560 ha, highly – 125,850 ha, very highly – 109,450 ha and saline soils – 27,520 ha. The absorbed bases in the soils of the massif were studied, and it was determined that they change depending on the amount of salts as follows: in mildly saline soils, Ca – 57.82–68.31%, Mg – 25.26–36.28%, Na – 5.49–6.43%; in moderately saline soils – 56.77–65.76%, 27.03–35.58%, 7.12–7.94%, respectively; in highly saline areas – 54.05–64.75%, 24.94–43.67% and 9.19– 14.42%. As you can see, the soils are mildly and moderately saline. The soils in the surveyed areas are saline to varying degrees (i.e., the average value of salts in the 0–100 cm layer of the soil varies between 0.25 and 1.00%). The biological product used in these soils contains a wide range of macro and microelements, humic acids, fulvic acids, amino acids, vitamins and enzymes that do not contain BioEcoGum mineral fertilisers. This biological product was used for the first time and one of the main goals was to study the improvement of water-physical properties of soils after its use. Therefore, the water-salt regime of the soils of the study area was studied on three experimental sites selected for the area, the number of irrigations for different plants, and their norms were determined taking into account the depth of groundwater in the soils and shown in tabular form. They are widely used in farms and these regions, taking into account the proposed irrigation norms and their quantity.

Soil water-salt regime as a factor in improving the reclamation state of irrigated lands

The paper considers improvements in the irrigation regime of the saz zone of the Ferghana Valley by developing reclamation regimes for irrigated lands. As a result of the research, the inflow of groundwater to the massif, the amount of unproductive evaporation of groundwater, the efficiency of drainage and the main factors determining the favorable reclamation state of meadow soils during irrigation were established. The relationship between the hydromorphic regime of soils and the consumption of water resources has been studied. In this work, a quantitative analysis of the processes of transfer of various ions in soils was carried out and a justification was given for the calculation models of salt transfer for meadow soils; It has been shown that under the conditions under consideration, the assessment of the salt regime of irrigated lands must be performed for not only Cl, but also Na, Ca, and Mg ions.

АКТУАЛЬНОСТЬ ПРИМЕНЕНИЯ ДОЖДЕВАЛЬНЫХ МАШИН В ЗОНАХ РИСКОВАННОГО ЗЕМЛЕДЕЛИЯ НА ПРИМЕРЕ САРАТОВСКОЙ ОБЛАСТИ

The Russian Federation has enormous potential for the development of agriculture. In addition, Russia has significant water resources, which are unevenly distributed throughout the country, which hinders the optimal development of agriculture. According to statistics, in 2022, about 50% of the agricultural land available in the Russian Federation is irrigated, and irrigated areas continue to grow. Irrigation of agricultural land is the most common and promising method of reclamation, aimed at providing plants with the required amount of nutrients, moisture and maintaining the optimal thermal and water-salt regime of soils. At the same time, it should be noted that a significant percentage of domestic agricultural land is located in the zone of risky farming, while the predominant part of fresh water resources suitable for irrigation is concentrated in non-agricultural areas, which entails a shortage of water for irrigation in agricultural regions. The presence of such a disproportion necessitates the saving of water resources during irrigation, which is achieved through the use of sprinklers. Irrigation with sprinkling machines is the most relevant for a number of other reasons: high productivity and quality of sprinkling; the possibility of full automation of the irrigation process; the ability to adapt to various soil and climatic conditions; the possibility of reverse movement during operation and movement without irrigation at idle; no need for a special field layout. The aim of the work was to analyze the climatic features of the Saratov region and the yield dynamics from 1987 to 2020 to justify the feasibility of using sprinklers to increase soil productivity. In the presented study, it was revealed that there is a direct relationship between the level of productivity of fodder, grain and vegetable melon crops and the number of sprinkler equipment, which indicates the need to develop a fleet of irrigation machines.

Regulation of the water-salt regime of irrigated lands in the lowerof the Syrdarya River

In general, the salinity of the water of the Syrdarya river, the current soil-reclamation state of the irrigated lands located in the lower reaches of the Syrdarya river are very poor. Soil salinity and salinity of collector-drainage waters are very high. For example, the average annual salinity of river water at the Tomenaryk gauging station is 2.0-2.5 g / l, and at the Kazalinsky gauging station - 3.0-3.5 g / l. Moreover, the process of soil salinization took place practically throughout the entire territory of the region. For example, according to the latest data, the area of ​​saline irrigated land in the Kyzylorda region is about 225 940 hectares, of which slightly saline - 87 574 hectares, moderately saline - 73 302 hectares, strongly and very strongly saline - 65 064 hectares. The Kyzylorda region is mainly engaged in the cultivation of rice (as well as alfalfa, corn for silage, sunflower, etc.). Considering this, secondary salinization was observed in rice fields due to poor performance of collector-drainage systems. After all, all of this is known to have a negative impact on crop yields. Therefore, we can get the best results only with the right watering with the right measures and capabilities. To optimize this issue, the article presents the current state of irrigated lands in the lower reaches of the Syrdarya river in the Kyzylorda region, as well as the results of work on regulating the water-salt regime. For this purpose, research work was carried out on 71.15 hectares of agricultural land Bidaikol (formerly Gigant), belonging to the Zhanakorgan-Shieli irrigation massif. It provides for the analysis of the amount of salts entering the soil with irrigation water and the release of salts from the soil by collector-drainage waters, measures to improve the ecological-reclamation state of the soil. And also the positive results of studies carried out on the site to improve the water-salt regime of the soil are presented. According to the research results, it was optimal to provide the fields with water through a specially prepared biofield planted with dense reed plants. It has been proven that purified irrigation water from the biofield is effective for irrigating forage crops. In addition, the reed itself is widely used in the republic as a fodder crop. Young reeds collected in August (at this time the reeds will be soft, and the leaves are green) are finely chopped and stored using a press using a special technology. Due to the growing importance of winter forage, the price of cane has increased significantly in the southern and southwestern regions of the country. For example, this year the price of 1 cane press fluctuated within 650-850 tenge. In addition, this spring there was a shortage of feed in the western regions (Aktau, Mangistau). Considering all these problems, the technology of water supply for irrigation through the biofield is more efficient.

Research of individual components of hydrological and hydrochemical regimes of the Danube River within the Ukrainian interval from Reni to Izmail

Introduction. This investigation aims at studying the individual components of the hydrological and hydrochemical regimes of the Danube River (within Ukraine) in connection with the widespread use of the river's water for water supply and irrigation in the southern region, as well as to ensure more effective regulation of water-salt regime of the Danube lakes using the Danube River as a main source for their water renewal. One of important aspects includes the study of the regime of the Danube River's suspended sediments brought to its delta due to their impact on the formation of the delta at the river's mouth of as well as due to the impact on siltation of deltaic and pre-delta lakes and canals connecting the lakes with the Danube River.
 Purpose. The purpose of the work is to study long-term and current trends related to changes in hydrological (water levels and discharges, suspended sediments runoff) and hydrochemical (mineralization) regimes of the Danube River within the Ukrainian interval from Reni to Izmail, internal annual distribution of water runoff, as well as suspended sediments runoff and mineralization during the years of varying water content.
 Results. The statistical analysis of long-term series of observations over the Danube River within the interval from Reni to Izmail resulted in discovering that time trends of average, maximum and minimum water levels (1921-2015) and discharges (1840-2015) indicate the presence of a weak increase in their growth over time, with a more pronounced increase in maximum water levels or discharges. The annual distribution shows the general synchronicity of fluctuations in runoff characteristics, and the maximum monthly values of water discharge differ have more pronounced seasonal fluctuations.
 The study shows the presence of a pronounced trend to reduction of suspended sediments runoff of the Danube River at Reni (for the period of 1840-2015), with their most intensive decrease over the period of 1990-2015. Annual distribution of average monthly suspended sediments runoff of the Danube River for the years with typical water content (for the period of 1978-2015) showed that they have seasonal fluctuations. At the same time, there is a decrease in the suspended sediments runoff along the length of the river from Reni to Izmail.
 The long-term course of average annual mineralization values of the Danube River at Izmail (1981-2015) is characterized by their decrease against the background of a small increase in average annual discharges. As per the annual distribution of mineralization values associated with all water content groups there are the periods related to the phases of the river's yearly water regime during and the economic use of water.
 Conclusion. Thus, the increase in the long-term period of the Danube River runoff within the interval from Reni to Izmail will contribute to the development of the region's economy and water supply, irrigated farming, regulation of the Danube Lakes filling with weakly mineralized river water. At the same time, the reduction of the suspended sediments runoff will restrain the siltation of the inlet canals connecting the lakes with the Danube River, which will improve the water renewal of the lakes with the river's fresh waters.

Evaluation of the effectiveness of drainage systems within the Desantne Village Council in Kiliya district of Odessa region

Relevance of research. Irrigated agriculture in the steppe regions of the southern Ukraine was naturally accompanied by negative phenomena. Among the most significant of them is flooding on agricultural land as a result water imbalance of the active water exchange zone when using irrigation. A significant part of this water as filtration losses from the irrigation network and directly when watering land goes to the aeration zone and reaches the surface of groundwater, increasing its supply. As a result, the groundwater level increases, the amplitude of which increases depending on the depth of groundwater, the intensity of irrigation, the distance from the irrigation network, the method of irrigation and other factors. In recent years, the number of actually irrigated areas located on irrigated lands is significantly reduced and at the same time the area of "dry" drainage is increasing. Therefore, one of the most pressing problems for today is the analysis of the condition of drainage and discharge network throughout Ukraine. Thus, the purpose of the research is to study the drainage and discharge network of the south-west of Odesa region to determine the current condition and prospects for its further use. The objectives of the research include monitoring of groundwater levels for the period of 1991 - 2019, determining the condition of the drainage and discharge network within the Desantne village council in Kiliya district of Odessa region. Theoretical methods of scientific research were used: monitoring, observation, analysis, survey, evaluation, comparison, generalization. The results of the study of closed drainage systems in the Desantne village council in Kiliya district of Odessa region showed that their effectiveness is insufficient. Recently, due to the cessation of irrigation at the research and production sites, groundwater level has fallen below the drains, the drainage has stopped operating and has been in a dry condition for a long time. The groundwater level in the drainage areas was at the depths of mainly 3.5-4.3 m. 24% of the inspection wells were destroyed, and 38.6% of them had no reinforced concrete cover rings. For a long time the closed horizontal drainage has been in unsatisfactory technical condition.
 Main conclusions: Drainage on irrigated lands should optimize the water-salt regime of soils, while moisture and salt reserves during the growing season in the root zone should be strictly dosed and ensure high crop yields as well as suitable hydrogeological and reclamation conditions on irrigated lands and adjacent areas. Introduction of large-scale parcellation of land and the land of reclamation funds as well as paid water use should not lead to the deterioration of the technical condition of the collector-drainage network.
 Drainage systems, as a means of groundwater level reducing, are especially relevant in land reclamation and flood protection of rural settlements. In the southern regions of Ukraine this problem was dealt with by Bayer R., Zelenin I., Lyutaev B., Miedviediev O., Miedviedieva O., Romashchenko M., Savchuk D. and others. Most systems were built on irrigation arrays in the Soviet times, ie 30-50 or more years ago. Redistribution and parcellation of agricultural land have led to the decline of the systems and the deterioration of their efficiency. Such works allow to analyze the operation of each drainage systems and make reasonable conclusions about their further use in terms of economic and environmental feasibility.

Water resources management in rice irrigation systems and improvement of ecological situation in rice growing river basins

Water resources management in the rice irrigation systems in Kazakhstan as well as water conservation and its efficient use are associated with technological processes control factors such as irrigation efficiency, layout of rice bays and their terracing. Managing technological processes in rice systems is complex, since there are significant deviations in the technological parameters of rice systems from the optimal. Therefore, in order to properly manage these processes, it is necessary to know the impact, its direction, assess the results of these impacts and develop an appropriate scientific and information base. The paper considers the impact of rice bays layout quality and terrace on the water-salt regime of soils, rice productivity and irrigation rate. Also, it proposes improvements to parameters of rice systems, water conservation, environmental situation in areas of rice cultivation and water resources management in rice systems.

Model of water-salt balance in the new irrigation territory of the karshin steppe

The article presents a methodology for the development of a model of salt transfer in the conditions of a stationary water-salt regime of soil-grounds, caused by furrow irrigation of cotton.

ФОРМУВАННЯ ГІДРОГЕОЛОГО-МЕЛІОРАТИВНОЇ ОБСТАНОВКИ НА РИСОВИХ ЗРОШУВАЛЬНИХ СИСТЕМАХ ПРИДУНАВ'Я ТА ШЛЯХИ ПІДВИЩЕННЯ ЇХНЬОЇ ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ З УРАХУВАННЯМ ПОГОДНО-КЛІМАТИЧНИХ РИЗИКІВ

The analysis of the main reasons for the unsatisfactory hydrogeological-reclamation state of the Danubian rice irrigation systems was carried out and the ways of its improvement due to the increase of drainage ability of irrigated lands of rice systems were considered. On the saline lands of the rice systems of the Danube delta drainage network is the main means of active and directed influence on the water-salt regime of the reclaimed area, formation of the regime of groundwater level, both in the growing season and in the not irrigated period for rice and attendant crops. Drainage network is essentially a determining factor in the formation of productivity of agricultural lands. An analysis of the efficiency of the drainage operation on the rice systems of the Danube Delta has shown that drainage built in accordance with the design standards that were in force at the time of construction does not provide uniform drainage ability in the area and the soil profile of rice fields. This is one of the main reasons for their unsatisfactory hydrogeological-reclamation state and reducing the yield of rice and attendant crops. By conducting optimization calculations according to the expense indicator, taking into account that optimal vertical filtration rate for the Danubian rice irrigation systems is at the level of 6...8 mm/day the optimal distance between the drains – 100 m was determined. Constructive improvement of existing rice systems with the drainage network in the form of open drains and distances between them – 250...500 m can be accomplished through the installation of additional separate closed drain-collectors. These drain-collectors are appropriate to arrange along the checks, with the set distance. For reducing the value of the vertical filtration rate in the drainage zone where it reaches 25 mm/day it is advisable to practice maintaining of water levels in the drainage network. Consequently, it is possible to achieve a reduction of the filtration rate to 4…5 mm/day. Developed measures and corresponding reconstruction of rice systems will enable to maintenance of satisfactory hydrological and hydrogeological regimes,ensure uniform salinity of soils during the cultivation of flooded rice, create favorable conditions for oxidation-reducing processes and maintenance of favorable ecological-reclamation state on the system.

Water-salt regime in the meliorated soils of the Shirvan Plain and their influence on agricultural plants productivity (Ujar Support Station)

Water-salt regime in the meliorated soils of the Shirvan Plain and their influence on agricultural plants productivity (Ujar Support Station)

ВОДНИЙ ТА СОЛЬОВИЙ БАЛАНСИ ОЗЕРА КАТЛАБУХ ЗА РІЗНИХ УМОВ ЕКСПЛУАТАЦІЇ ВОДОЙМИ

Katlabukh Lake is a part of the Danube Lakes system and is one of the surface water sources for water supply, for agricultural needs and irrigation of the region. Changing the conditions of operation and regulation of the reservoir led to a decrease of water levels and an increase of salinity, which makes it impossible to use water for different management needs. Calculations of the water and salt regimes of the lake based on the solution of the equation of balance said that in the water balance of Katlabukh Lake the main volume of the revenue part for the period 1980-2018 was precipitation (36.1%) and water inflow from the Danube River (38%), and the expenditure part – evaporation together with transpiration (50.5%). Salt flow into the lake is mainly due to surface inflow (53.4%) and water of the Danube River (25.5%), and loss of irrigation (45.1%) and water discharges to the Danube River (31.9%). Simulation modeling of the water-salt regime of the Katlabukh lake under different conditions of exploitation of the reservoir showed that corrective management measures are needed to improve the qualitative indicators of the water in the reservoir. They consist in the fact that for three summer months it is necessary to carry out forced pumping of poorly mineralized water from the Danube River to compensate for evaporation from the water surface (on average in volumes of the order of 55 million m3) or to carry out fences of water from the lake for irrigation in 60 million m3. This will allow to reach the design values of water mineralization in the lake equal to 1.0-1.5 g/dm3. Thus, addressing a range of problems to conserve and restore the rational use of the natural resources of Katlabukh Lake requires effective managerial water management activities that require additional feasibility studies.

BOUNDARY VALUE PROBLEM FOR THE ALLER — LYKOV MOISTURE TRANSPORT GENERALIZED EQUATION WITH CONCENTRATED HEAT CAPACITY

The article considers the Aller Lykov equation with a Riemann Liouville fractional time derivative, boundary conditions of the third kind and with the concentrated specific heat capacity on the boundary of the domain. Similar conditions arise in the case with a material of a higher thermal conductivity when solving a temperature problem for restricted environment with a heater as a concentrated heat capacity. Analogous conditions also arise in practices for regulating the water-salt regime of soils, when desalination of the upper layer is achieved by draining of a surface of the flooded for a while area. Using energy inequality methods, we obtained an a priori estimate in terms of the Riemann Liouville fractional derivative, which revealed the uniqueness of the solution to the problem under consideration.

FORMATION OF WATER REGIME AND SALT BALANCE OF A RICE CARD-CHECK UNDER THE INFLUENCE OF THE IRRIGATION-DRAIN

The effectiveness of card-checking of the wide front of flooding and discharging of water (KCD) in comparison with Krasnodar type maps (CCT) has been investigated. On the basis of long-term field research, the role of irrigation-discharger in the formation of water and salt regime on irrigation rice maps has been defined. The research was conducted on two experimental plots each consisting of two card-checks and maps of the Krasnodar type. In both areas during all years of research, a shortened regime of rice flooding under the condition of application of anti-herbicide herbicides was maintained. We have revealed that on the cards of checks of the wide front of flooding and discharging with different parameters a more favourable water-salt regime during irrigation was created in comparison with Krasnodar type maps. At KCD in the best possible terms there is an initial flood, which cannot be said about control CCT. Thanks to the drainage action of the irrigation system, the card was washed more intensively after the discharge of water. The presence on the KCD of the irrigation canal allows operatively, evenly throughout the length of the card to submit and dispose of water, as well as to play the role of shallow drains, due to which more intense drying and distilled soils on the KCD. The advantage of card-checks of the wide front of flooding and discharging at the technological discharges of water from rice cards is explained by the fact that the discharge of water into the irrigation channel is carried out along its entire length (about 900 m) there, while on the control CCT with the help of four check water discharges with low bandwidth. As a result of the balance-sheet research, it was found that at a mitigation distance of 200 m on card-checks, the salinity of the upper 1.2 m layer of soil on average during the research was 4 % higher than on control CCT, and at a short distance of 250 m, a decrease in salt reserves at KCD was 8 % higher than on control CCT. It has been established that on map-checks of the broad front flooding and discharging of rice yield on average by 4-5 centner/ha was higher than on the CCT of the corresponding parameters.

Change of hydrological and morphometric characteristics of Kuyalnik Liman after inflow of seawater

The water level of the liman, volume and area of surface reduced to record low values as a result of intensification of evaporation process in 2014. By the autumn of 2014 the liman was on the verge of extinction. Entry of seawater in the liman through the pipeline began in December of 2014 to prevent environmental degradation of the liman.
 Purpose of this publication consists in analyzing the changes of hydrological and morphometric characteristics of Kuyalnik liman in 2014-2016 associated inflow of sea water.
 Methods of study. Hydrological and morphometric characteristics of the liman were calculated on the basis of: field studies, bathygraphic curves, data of satellite images «Landsat».
 Results. There was dynamics of change of water surface area, volume, level and salinity of liman’s water during the driest periods, at the time and after the inflow of seawater into the liman. The results of measurements of discharge of seawater and coastal watercourses. The effect of evaporative processes taking into account temperature conditions (Odessa, Lyubashevka) on liman’s hydraulicity after the cessation of seawater supply was analyzed.
 Conclusion. Inflow of seawater into the liman after the first entry of seawater allowed to temporarily stabilize water-salt regime of the liman, however, hydrological and morphometric characteristics of the liman in autumn of 2015 almost returned to the values of early autumn of 2014. During subsequent inflows of seawater into the liman it is desirable to maintain the regime observed during the inflow of water in 2014-2016.

Modeling of the water-salt regime dynamics of the Aral sea and its coastal zone

Modeling of the water-salt regime dynamics of the Aral sea and its coastal zone

Changes in the Composition and Properties of Meadow Solonchaks of the Ili Alatau Foothill Plain in the Republic of Kazakhstan during a Long Postmeliorative Period

The optimal depth of the groundwater table and the water-salt regime is of importance in the postmeliorative period. The scope of these studies is to provide scientifically grounded assessment of previously reclaimed soils (water irrigation with a total norm of 5000 m3/ha under conditions of deep horizontal drainage, 1986-1989) in the postmeliorative period of 2015-2016 and to develop parameters for forecasting their meliorative regime. This work was conducted with the use of traditional ground-based methods of soil research. As a result of the research, data were obtained that allow assessing the water-salt regime, groundwater levels, their mineralization, as well as changes in the physical and hydrophysical properties of the previously reclaimed meadow solonchaks under natural conditions and under alfalfa in the background of deep, horizontal drainage and developing soil biota control techniques, including improvement of the meliorative state of the soil and indicators of their effective fertility.