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Israeli team (Ben-Gurion University of the Negev): Dr. Alexander Yakirevich Principal Investigator, Dr. Eilon Adar co-Principal Investigator, Dr. Anil Mishra Postdoc (Nepal), Irina Aidarov M.Sc. student, Dr. Ludmila Katz chemist, Natalia Bondarenko technician.
Kazakhstan team (Institute of Hydrogeology and Hydrophysics MOS RK): Academician Vassily Vesselov co-Principal Investigator, Doctor of technical sciences Vladimir Panichkin co-Principal Investigator, Dr. Nonna Zakharova senior researcher, Dr. Ludmila Trushel senior researcher, Dr. Tamara Vinnikova senior researcher, Dr. Oxana Miroshnichenko senior researcher, Mr. Vladimir Ostanin leading engineer, Dr. Alexander Engels leading engineer.
Many years of excessive irrigation and massive exploitation of local water resources in the Akdalinsky sand dune terrain of the Ily river basin have caused considerable deterioration of soil and water in the area. Extensive flood irrigation over sandy soils, leading to leaching of nutrients from the root zone, soil swamping, alkalization and secondary salinization, have resulted in pollution of surface and underground water, associated with significant decreases in crop yield and quality of life of the local population. This project allowed quantitative characterization of the complex hydrological and hydrochemical features in the Akdalinsky agricultural land. Based on this characterization, recommendations were drawn up to decrease the negative impacts of anthropogenic activities on the soil and water environment in the cultivated sand dunes area. The approach used for this study was based on analyses and integration of field data, and detailed numerical simulations of different agricultural production and water management strategies.
The innovative aspects of the project lie in further development of the methodology to determine appropriate ecological water demand for irrigation in drylands. We demonstrate that crop pattern changes will reduce the water consumption for irrigation and return flow of drainage water to the Ily River. Results indicate that increasing the area of rice fields will further lead to land swamping and deteriorating hydro-ecological conditions. Leachate of polluted water from the irrigated area returns into the Ily River via seepage and surface drainage, affecting the water quality of the Ily delta. Alternatively, decreasing the proportion of rice fields in the area will lead to lowering of the groundwater level to 3-5 m below surface and secondary salinization of a significant part of this land. Application of models to simulate different water management scenarios enabled us to find the optimal relation between areas of rice and other crops. For example, keeping an area of 4200-4500 ha for rice fields out of 15,200 ha in the Bakhbakhty region is the most rational solution for this region.
The results of this research have been used for planning water and agricultural activities in the region in the framework of a project for reconstructing irrigation and drainage systems. Specifically, the GIS-based database and developed model of hydrological and hydrochemical conditions are being included as part of the automated information system for monitoring ecological conditions in the study area. The Kazakhstan Institute of Hydrogeology and Hydrophysics (IHH) participates in transfer of the developed technology and training of water authority professionals. The model will enable estimation of the efficiency of planned activities regarding reconstruction of the Akdalinsky irrigation system, in order to predict their effect on conditions in the study area for different crop rotation scenarios.
As a result of this project, the computing facilities in the Laboratory of Modeling and Hydrodynamics of the IHH were strengthened. The Kazakh researchers were trained in using the Groundwater Modeling System, geo-information system MapInfo and database management system FOXPRO.
In many parts of the world, significant portions of irrigated land are subject to degradation, salinization and contamination, making irrigation unsustainable [Scherr, S. J. and S. Yadav, 1996. Land degradation in the developing world: Implications for food, agriculture, and the environment in 2020. Food, Agriculture, and the Environment Discussion. Paper 14. Washington, D.C.: International Food Policy Research Institute]. Due to excessive irrigation and consequent rising groundwater levels, the installation of expensive drainage systems is required, increasing the cost of crop production. This also induces the problem of disposal of drainage effluent, which is usually loaded with salts and, when thrown into the river, contaminates the river downstream. The problem is therefore how to use water more efficiently in order to prevent environmental damage and to get a better return for the cost of supplied water [D. Hillel, in Fresh Water resources in Arid Lands, 1997].
The conditions of water and soil resources in Kazakhstan are in many ways determined by the influence of past water-related technological development and agricultural activities. During the Soviet period, Kazakhstan implemented many poorly designed and constructed land reclamation projects, associated with the diversion of water from far basins. The processes of environmental deterioration can be observed in the Ily-Balkhash region, where a big industrial-agricultural complex was established over sand dune terrain based on water diversion from the Ily river. A total area of 30,000 ha were irrigated for growing rice, wheat, corn, tobacco, sugar beet, vegetables and fruit. Previous research revealed that many years of excessive irrigation and unsustainable exploitation of local water resources in the Akdalinsky land of the Ily River basin caused considerable deterioration of soil and water, including leaching of nutrients from the root zone, soil swamping, alkalization and secondary salinization, and pollution of surface and underground water [Vesselov, V.V., Panichkin, V.Yu., Adar, E., Yakirevich, A., Zakharova, N.M., Miroshnichenko, O.L, Trushel, L.Yu. and Shakibaev, I.I. 2005. Geoinformation-mathematical modeling of hydrogeological conditions of the Akdalinsky irrigated land. Proc. of National Academy of Science of Kazakhstan, ser. Geology, 1, 2005, 86-95], [Vesselov, V., A.G. Begaliev, N.M. Zaharova and I. N. Gale, 1996. Water Resources of the Ily-Balkhash Basin, Kazakhstan. Technical Report WD/96/52, British Geological Survey, Nottingham, UK, 48p.]. Observations show significant levels of pesticides and biogenic contaminants in drainage water. The latter is recharged back into the Ily and Karatal Rivers, which, despite their poor water quality, are used by the local downstream population for domestic purposes. A decrease in discharge of the rivers in the basin was detected, together with a lowering of the water level in the Balkhash Lake. Desertification features have been observed during the last 15 years over the entire area, associated with qualitative and quantitative changes in groundwater, which is the central component of the ecological system. Therefore, an assessment of rational strategies for exploitation of water resources and prevention of contamination of the soil and water environment is a primary task. Investigation of these problems can be done by developing a physical and hydrochemical database and by applying mathematical model analyses. For example, applying a global water and food analysis model [Cai, X., 2004. Optional water development strategies for the Yellow River Basin: Balancing agricultural and ecological water demands. Water Resour. Res., 40] demonstrated that there is little hope of resolving the conflict between agricultural water demand and ecological water demand in the Yellow River Basin.
The aim of this research was quantitative elaboration of a complex of hydrological features in order to decrease the negative effects of anthropogenic activities on the soil and water environment in the agricultural area of the Ily River basin. This is based on: 1) Assessing the extent of pollution and salinization of surface and underground water; 2) Adapting and implementing models for predicting the path and rates of pollutant migration and for simulating scenarios under various types of water resources exploitation; 3) Analyzing the results of hydrological simulations to determine measures for decreasing the risks of environmental pollution; 4) Assessing suitable scenarios for sustainable development of water resources in the study area.
The innovative aspects of the project involve further development of the methodology to determine appropriate ecological water demand for irrigation in drylands. The aim was to examine how changes in crop pattern will affect the water consumption for irrigation and return flow of drainage water to the Ily River. The results of simulations for different agricultural and water application scenarios will help planners in protecting the local environment and establishing sustainable cultivation in this area. The "Jetisuss" hydrogeological-reclamation expedition by the Kazakhstan Ministry of Agriculture has started using the results of this research. This organization is responsible for water management in the area, participating in activities concerning re-design and reconstruction of the Akdalinsky irrigation system. The staff of this expedition helped in organizing field trips by Kazakhstan and Israeli investigators to the research site, and supplied data from field observations.
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