Basins In Central Asia Research Articles

Trend analysis of temperature and precipitation in the Syr Darya Basin in Central Asia

By investigating temperature and precipitation data from eight meteorological stations in the Syr Darya Basin (SDB) during 1881–2011 and 1891–2011, we analyzed trends using the Mann-Kendall (MK) test. Our results indicated that there was a notable increasing trend in annual temperature of 0.14 °C/decade (P < 0.05) and step change points in 1989 (P < 0.05). Similarly, annual precipitation showed a significant rising trend (P < 0.001) at a rate of 4.44 mm/decade and step change points in 1991 (P < 0.05). Overall, temperature and precipitation increases were more rapid in the plains than in the mountain areas. Furthermore, we found that temperature in the SDB region is strongly associated with the Asian Polar Vortex Area Index (APVAI, correlation coefficient: R = −0.701, P < 0.01) rather than with carbon dioxide emissions, especially in the plains area. For precipitation, the correlation coefficient is strongly associated with the Tibet Plateau Index (TPI, R = 0.490, P < 0.01), followed by the Antarctic Oscillation Index (AAOI, R = 0.343, P < 0.01), and the correlations in the plains are higher than those in the mountains. It is anticipated that the results of this study will further the understanding surrounding climate change in the SDB.

What Makes India such a Good Indenter

Since about 50 Ma, the ongoing continental collision of India and Asia has led to widespread deformation within Central Asia. A similar pattern results when a rigid indenter pushes into a deformable medium. Therefore, for simplicity, many models have assumed that continental India is rigid. However, in reality, its northern margin has deformed, producing the Himalayan arc and syntaxes. To account for these, we have made physical models containing continental or oceanic plates. For realistic plate configurations and boundary conditions, our models have reproduced the Himalayan arc and syntaxes, as well as the asymmetric distribution of mountain ranges, high plateaus and basins in Central Asia. On this basis, we suggest that two features make India a good indenter. First, the Indian continental crust is buoyant and so resists subduction. Second, the surrounding oceanic crust is mechanically strong. The result is a V-shaped indenter, buoyant in the middle and strong at the sides.

Coping with changing water resources: The case of the Syr Darya river basin in Central Asia

a b s t r a c t This paper discusses how climatic-hydrological and socio-political developments will affect water allocation in the Syr Darya river basin and which adaptation measures will be needed to cope with changing water resources. In view of the geo-political complexity, climate-driven changes in water availability are of particular importance in this region. Water shortages during summer will become more frequent as precipitation is expected to further decrease and glacial meltwater releases will decrease in the long-term due to reduced glacier volume. Being the main valve to the entire Syr Darya river system, the Toktogul reservoir in Kyrgyzstan could take over, at least partly, the role of glaciers as seasonal water redistributors, thus allowing the generation of energy in winter – benefiting upstream countries – and irrigation for large-scale agriculture in summer – benefiting downstream countries. To date, however, there is no regional consensus on a balanced reservoir management, which currently favours irrigation according to past Soviet priorities. Moreover, the perception of water as a ‘national concern’ in Central Asia discourages efforts towards cooperation between states at the regional level. So far, climate change adaptation has focused on technical rather than institutional solutions. We suggest that policy-relevant adaptation measures should include consistent data collection and dissemination, cross-sectoral collaboration, promotion of national responsibility and initiative, and agreeing on a regional strategy.

Estimation of daily average temperature using multisource spatial data in data sparse regions of Central Asia

The distribution of the daily average air temperature with high spatial resolution is vital for hydro-ecological applications. The air temperature usually recorded at fixed-point stations provides little distribution information and easily suffers from the scarce amount and uneven distribution of the stations in the data sparse regions. In this study, a method based on multisource spatial data was developed to estimate the spatial distribution of daily average temperature, especially for data sparse regions. In this method, the instantaneous temperature was retrieved first using the moderate resolution imaging spectroradiometer data, which was then transformed to a daily value using transformation equations. Second, the global land data assimilation system air temperature data were spatially downscaled and used to improve the data accuracy from step 1 at low temperatures. This method was applied in the Ili River basin in Central Asia, and the results were evaluated against data from two stations’ observations and in situ data from a field test site. The results showed the correlation coefficient varies from 0.90 to 0.94 and the root mean square deviation is ∼3°C , indicating the generated temperature matched the observations well. This suggests the method is an alternative for data sparse regions.

Evaluation of areal precipitation estimates based on downscaled reanalysis and station data by hydrological modelling

Abstract. In data sparse mountainous regions it is difficult to derive areal precipitation estimates. In addition, their evaluation by cross validation can be misleading if the precipitation gauges are not in representative locations in the catchment. This study aims at the evaluation of precipitation estimates in data sparse mountainous catchments. In particular, it is first tested whether monthly precipitation fields from downscaled reanalysis data can be used for interpolating gauge observations. Secondly, precipitation estimates from this and other methods are evaluated by comparing simulated and observed discharge, which has the advantage that the data are evaluated at the catchment scale. This approach is extended here in order to differentiate between errors in the overall bias and the temporal dynamics, and by taking into account different sources of uncertainties. The study area includes six headwater catchments of the Karadarya Basin in Central Asia. Generally the precipitation estimate based on monthly precipitation fields from downscaled reanalysis data showed an acceptable performance, comparable to another interpolation method using monthly precipitation fields from multi-linear regression against topographical variables. Poor performance was observed in only one catchment, probably due to mountain ridges not resolved in the model orography of the regional climate model. Using two performance criteria for the evaluation by hydrological modelling allowed a more informed differentiation between the precipitation data and showed that the precipitation data sets mostly differed in their overall bias, while the performance with respect to the temporal dynamics was similar. Our precipitation estimates in these catchments are considerably higher than those from continental- or global-scale gridded data sets. The study demonstrates large uncertainties in areal precipitation estimates in these data sparse mountainous catchments. In such regions with only very few precipitation gauges but high spatial variability of precipitation, important information for evaluating precipitation estimates may be gained by hydrological modelling and a comparison to observed discharge.

Geochemical characteristics and environmental significance of Talede loess–paleosol sequences of Ili Basin in Central Asia

The loess–paleosol deposit in Central Asia is a sensitive indicator of the evolution of the quaternary paleoclimate in the Westerlies, providing insight into the quaternary climate history and its relationship with global climatic changes. Based on the geochemical analysis of elemental composition of densely sampled strata from Talede loess–paleosol sequence in the Ili Basin, the results showed that SiO2 had the highest major elements content, followed by Al2O3. The order of compositional abundance of major elements was generally as follows: SiO2 > Al2O3 > CaO > Fe2O3 > MgO > Na2O > K2O. Trace elements (i.e. Rb, Sr, Sc, Ni, Cu, Ga, Mo, Y, Pb, Th) in the paleosol layers (i.e. S 0, S m, S 1) and the loess layer of L 1 were enriched relative to underlain loess (L 2) horizons, except for the contents of Zr, Cs, Nd, and La in paleosol layers. All of geochemical proxies, such as enrichment factor, Rb/Sr ratio, eluvial coefficient (K i ) and chemical weathering index, display no obvious differentiation in the Talede loess–paleosol deposit. The results indicate that the weak chemical weathering, greater evaporation and low effective moisture in Ili Basin, are to a degree weaker than those in the China Loess Plateau and the climate was warm–dry during the interglacial period. In addition, the loess of Ili area is rich in schistose minerals and implies that the loess may come from the deserts of Central Asia and it may be closely related to the widespread aridification of Central Asia.

Irrigation Effects on Hydro-Climatic Change: Basin-Wise Water Balance-Constrained Quantification and Cross-Regional Comparison

Hydro-climatic changes driven by human land and water use, including water use for irrigation, may be difficult to distinguish from the effects of global, natural and anthropogenic climate change. This paper quantifies and compares the hydro-climatic change effects of irrigation using a data-driven, basin-wise quantification approach in two different irrigated world regions: the Aral Sea drainage basin in Central Asia and the Indian Mahanadi River Basin draining into the Bay of Bengal. Results show that irrigation-driven changes in evapotranspiration and latent heat fluxes and associated temperature changes at the land surface may be greater in regions with small relative irrigation impacts on water availability in the landscape (here represented by the Mahanadi River Basin) than in regions with severe such impacts (here represented by the Aral region). Different perspectives on the continental part of Earth’s hydrological cycle may thus imply different importance assessments of various drivers and impacts of hydro-climatic change. Regardless of perspective, however, actual basin-wise water balance constraints should be accounted to realistically understand and accurately quantify continental water change.

『エーテルの道』から『ジャン』へ

It is well known that the style of Andrei Platonov (1899–1951) underwent a notable change during the first half of the 1930s. This article aims to concretely analyze how his writing evolved during this period by comparing two of his novellas: Efirnyi trakt, written in 1927, and Dzhan, written in 1935. These works were written, respectively, before and after Platonov altered his style. However, there is another reason to compare these two works in particular. These novellas have entirely different themes; however, they contain similar elements in their plots. Therefore, they are relatively easy to compare in order to show how the author’s style underwent a transformation. Efirnyi trakt is about physicists who explore a way to increase or decrease materials at will. In contrast, Dzhan is about a youth who is sent from Moscow to rescue an ethnic group that is facing almost certain destruction in the Sary-Kamysh basin in Central Asia. Despite the apparent differences between these two works, each has a protagonist with a high level of education, and who, while eager to accomplish his mission, suffers a setback. A closer look at these works makes it clear that the position of the protagonist in relation to the natural environment undergoes a critical change. In other words, the relationship is turned upside down. In Efirnyi Trakt, the physicists are active agents dealing with the natural environment, and they exploit it for their own gains. In Dzhan, the young man is vulnerable to predation by eagles, and is therefore relatively passive to nature. In Europe after World War I, Platonov was not unique in characterizing the man by putting emphasis on his passiveness. However, Platonov was original in expressing the passivity of man with respect to the natural environment, not only through the expression of feelings and reflections of the protagonists but also by inverting the relationship between his protagonists and the natural environment. A comparison of these two novellas makes this clear. It is well known that since the mid 1930s, Platonov attempted to write works that faithfully accorded with the principles of socialist realism. Yet, despite his efforts, as seen in Dzhan, his own literary cosmos kept evolving.

Water Quantity and Quality in the Zerafshan River Basin: Only an Upstream Riparian Problem?

In discussing the 1997 UN Watercourses Convention, McCaffrey (1998) gave a theoretical example of the late-developer problem. This paper complements that theoretical example with a real case study of the Zerafshan basin in Central Asia. While McCaffrey addressed the water quantity issue in his example, the focus here also includes water pollution. The aim of the paper is to analyze some of the provisions of the mechanisms in the field of international water law—the Helsinki Rules and the UN Watercourses Convention—for water quantity and quality aspects, as well as to provide an insight into the basin regarding these two aspects.

The Mineral Dust Cycle in EMAC 2.40: sensitivity to the spectral resolution and the dust emission scheme

Abstract. This first detailed analysis of the mineral dust cycle in the ECHAM5/MESSy Atmospheric Chemistry (EMAC) model system investigates the performance of two dust emission schemes, following the approach of Balkanski et al. (2004) and Tegen et al. (2002), respectively, and the influence of the horizontal model resolution. Here the spectral resolutions T42, T63, T85, and T106 are investigated. A basic sulphur chemistry, enabling the coating of insoluble dust particles to make them soluble, is employed in order to realistically describe the ageing and wet deposition of mineral dust. Independent of the dust emission scheme the five-year simulations with the horizontal resolutions T42 and T63 produce unrealistically high emissions at some grid points in the Tarim Basin in Central Asia, leading to very high dust loads in polar regions. With these coarse resolutions, dust source grid points in the basin and elevated grid points of the Himalayas with high wind speeds cannot be distinguished, causing this overestimation. In T85 and T106 these regions are well separated and considerably less dust is emitted there. With the chosen model setup, the dust emission scheme by Balkanski et al. (2004) places the global maximum of emissions in the Thar Desert in India. This is unrealistic as the Sahara Desert is known to be the largest dust source in the world. This is the main deficiency of this scheme compared to the one by Tegen et al. (2002), which, based on a qualitative comparison to AEROCOM data, produces a very reasonable distribution of emissions and dust loads in simulations with resolutions T85 and T106. For future climate simulations with EMAC focusing on mineral dust, we recommend to use the dust emission scheme by Tegen et al. (2002) and a model resolution of at least T85. Simulations of two selected episodes and comparison to observational data sets show that in this model configuration EMAC is able to realistically simulate also intense, episodic events of dust emission and long-range transport.

A water accounting procedure to determine the water savings potential of the Fergana Valley

The Syrdarya River basin in Central Asia exhibits symptoms of scarcity because of growing competition between hydropower upstream and environment, cities and agriculture downstream. Different approaches to water management, based on water savings in agriculture could relieve the stress of competition, yet keep alive a vibrant agriculture. The Fergana Valley, a highly productive area within the upstream of the Syrdarya River, was analyzed to determine the water savings potential of agriculture. This paper used a water accounting procedure to identify both the scope for savings and the strategies to realize those gains. Significant nonproductive depletion of water at 2681–4164millionm3 (Mm3) was identified in the form of evaporation, flows to sinks and pollution. The water-saving potential is estimated at 2823Mm3 annually, which is about 10% of the total inflow into the area, through a range of practical approaches. This strategy would bring regional benefits by reallocation of surplus winter flow from the upstream for summer use in the downstream.

Of transboundary basins, integrated water resources management (IWRM) and second best solutions: the case of groundwater banking in Central Asia

This paper tells the story of trade-off between hydropower and irrigation and its implications for groundwater use in Syrdarya basin in Central Asia. With the independence of the central Asian republics, this trade-off has become a transboundary issue. Efforts to coordinate bilateral action using integrated water resources management (IWRM) principles of basin-wide cooperation have not yet yielded the hoped for results. This paper shows that there could be a ‘second best’ option of solving at least part of this transboundary problem by ‘banking’ winter flows released for hydropower production in Kyrgyzstan in the underground aquifers of Uzbekistan's Fergana Valley and extracting it for irrigation in the summer months.

Triassic-Jurassic biodiversity, ecosystems, and climate in the Junggar Basin, Xinjiang, Northwest China

The Junggar Basin, one of the largest continental basins in Central Asia, represents a landlocked sedimentary environment that has been cut off from marine influence since the late Palaeozoic (Hendrix et al. 1992). The basin contains a largely fossiliferous sedimentary succession from the Permian to the Late Cretaceous (Dong 1992). Throughout the Mesozoic, the Junggar Basin maintained a mid-latitude position, making it particularly interesting for palaeoecologic and palaeoclimatic studies (e.g., Eberth et al. 2001). The focus of this issue is on the Late Triassic and Jurassic fluvio-lacustrine strata in the southern Junggar Basin that have yielded a wealth of continental biota in the last decade (e.g., Maisch et al. 2003), but other areas of the basin are also considered. The nine articles of the Special Issue report on the palaeontological and sedimentological research that has been conducted by the “Sino-German Joint Group of Palaeontology and Geosciences” funded between 2005 and 2009 by the Sino-German Center for Research Promotion (Beijing). The topics addressed are basin development, sedimentology, reconstruction of the Jurassic forest, palaeoclimate, and the palaeobiogeographic and palaeoecologic implications of aquatic and terrestrial organisms such as hybodontid sharks, turtles, crocodiles, squamates, mammals, and plants. In its multidisciplinary approach, the Special Issue provides the first comprehensive overview of the evolution of the Late Triassic to the Late Jurassic ecosystems in the Junggar Basin with an emphasis on its southern part. Bian et al. provide an overview on the geological evolution of the Junggar Basin from the Early Permian onward when the sea regressed to the southeast and the basin became landlocked. The Lower to Middle Triassic is characterised by alluvial fan and delta systems that are overlain by lacustrine deposits of the Upper Triassic. In the Lower and Middle Jurassic, coal-bearing braid delta systems developed while the Upper Jurassic was widely eroded except for a depocentre along the southern part of the Junggar Basin between the cities Manas and Urumqi. The Cretaceous is characterised by continuous and homogeneous lacustrine conditions with the depocentre located in the basin centre. During the Paleogene, braid delta systems developed, whereas with the early Neogene, sedimentation was restricted to the southern part of the basin, when the north Tianshan experienced a rapid uplift and northward over-trust. Ashraf et al. present a review and new data on the Triassic and Jurassic palaeoclimate development in the Junggar Basin. New lithological data mainly derive from the southern part of the basin and cover a period from the Late Triassic (Norian) to the latest Jurassic (Tithonian). Based on new palynological data, the authors convincingly demonstrate that the base of the Middle Jurassic does not coincide with the lithostratigraphical formation boundaries. T. Martin (*) Steinmann-Institut fur Geologie, Mineralogie und Palaontologie, Universitat Bonn, Nussallee 8, 53115 Bonn, Germany e-mail: tmartin@uni-bonn.de

The Neogene Xiyu Formation, a diachronous prograding gravel wedge at front of the Tianshan: Climatic and tectonic implications

The Tarim and Junggar basins in central Asia are capped by a thick pile of conglomerates, called the Xiyu Formation, that are commonly linked to a change in climate and/or accelerated uplift near the Plio-Pleistocene boundary. In order to better understand their origin and significance, we carried out a combined structural and magnetostratigraphic study in the Quilitage syncline (southern Tianshan), where the base of the Xiyu conglomerates is observed at both sides of the syncline. A balanced cross-section shows that, even at a local-scale, the base of the Xiyu conglomerates cannot be regarded as a single continuous stratigraphic layer. On the southern flank of the Quilitage syncline, we collected 172 samples collected for magnetostratigraphic dating identify 17 polarity chrons that date the new section from 5.2 to ~ 1.7 Ma and constrain the base of the Xiyu conglomerate here at ~ 1.7 Ma. This is 4.2 Ma younger than the age of the Xiyu previously found on the northern limb of the same syncline. Together with other magnetostratigraphic studies carried out around the Tianshan, our study unambiguously demonstrates that the onset of deposition of the Xiyu conglomerates is diachronous, and that the conglomerates are systematically younger toward the basin. Consequently, the Xiyu Formation should not be considered as a chronostratigraphic marker related to any particular tectonic or climatic event, but is instead a prograding gravel wedge that has prograded over the underthrusting forelands. A synthesis of chronologic and structural results yields progradation rates over the last 10 Ma on the order of ~ 2.0 mm/yr and ~ 3.9 mm/yr south and north of the Tianshan Mountains respectively. These rates are comparable to the shortening rate across the Tianshan range, suggesting that underthrusting is the main factor governing the progradation rate of the Xiyu Formation.

Managing water‐use trade‐offs in a semi‐arid river delta to sustain multiple ecosystem services: a modeling approach

AbstractManaging trade‐offs among water uses in a river basin to sustain multiple ecosystem services is crucial for adaptation to changing river flow regimes. Here we analyze the trade‐off between irrigation and fisheries in the Amudarya, a semi‐arid river basin in Central Asia, using an optimal control and an agent‐based modeling approach. With the optimal control approach (OCA), we identify the economic and ecological conditions for water sharing in a regime where a social manager controls water withdrawals and fish harvesting. With the agent‐based model (ABM), we relax some of the assumptions of the OCA to investigate how localized, individual agents with varied water use histories adapt their water use activities to local resource conditions. Variation in the farmers’ initial labor allocations to the two activities results in regimes with only one activity or both. Global returns and income equality are highest in a mixed regime. The mixed regimes also are more robust to water variability because fishing activities can compensate for decreased agricultural performance in the midstream regions. Thus, allowing for multiple uses can improve the coupled social‐ecological system's performance and its resilience. We also observe a lock‐in effect similar to the current situation in the Amudarya, where agriculture is the dominant water use and transition to a more balanced allocation has proven to be extremely difficult. As in the ABM, this can to some extent be attributed to the difficulties of achieving sufficient revenues from fishing when agricultural activities upstream are high. Regulations or incentives are needed to overcome those barriers, and to facilitate progress towards integrated water management.

On Achieving Fairness in the Allocation of Scarce Resources: Measurable Principles and Multiple Objective Optimization Approaches

Equity principles are embedded within a multiple objective framework for obtaining optimal solutions to a generic allocation problem, such as the fair distribution of water, energy, or other types of key resources among users in society. Because of the great import of fresh water as a scarce and diminishing resource within and among many nations of the world, the equity concepts are used in the allocation of water rights and subsequent water transfers or trades among users to improve the economic efficiency of water utilization. More specifically, water allocation is formulated as a generalized multiple objective problem and then the measurable fairness principles are used in the development of two approaches for equitable water rights allocation. In particular, the proposed priority-based maximal multiperiod network flow programming method has a social aggregation function satisfying the monotonicity and priority principles, and thus is a priority equitable allocation approach. The lexicographic minimax water shortage ratios method, which satisfies the principles of monotonicity, impartiality, and equitability, generates perfectly equitable solutions. The priority ranks and weights used in the two proposed approaches, respectively, are designed to achieve fair treatment of all the competitors for access to limited water resources and constitute important parameters. The capabilities of the approaches are tested and demonstrated in applications to the Aral Sea Basin in Central Asia and the South Saskatchewan River Basin in Western Canada.

Simulation of Processes Involved in Soil Salinization to Guide Soil Remediation

The man-made development of lands for irrigated agriculture has provided benefits, but in some schemes has resulted in catastrophic problems arising from soil salinization including those in the Aral Sea Basin in central Asia and the Murray-Darling Basin in Australia. Soil salinization is a gradual process and the impact of salt intrusion is noticeable after several years of development, typically ranging from 10to30years. In central Asia salt water management has historically been based on rules of thumb with mixed results. A coupled surface and ground water model, HYDRO-GW, has been developed with the facilities to model the processes in the root zone and in the unsaturated and saturated subsurface system. The model is applied to the Kashkadarya irrigation area in Uzbekistan to assess the impact of various changes in land and water management practices on reducing salinity levels. Simplified equations have been presented which have potential application for assessing the salinization process and can be used as precursors to detailed assessment using a coupled surface and ground water model.

Decrease of river runoff in the Lake Balkhash basin in Central Asia

AbstractThe decrease of river runoff draining into Lake Balkhash in Central Asia was investigated using hydrological and meteorological data over a long‐term period. The data from the difference integral curves of the annual runoff from 1911 to 1986 suggested that a low‐flow period began in 1970 in the River Ili, and in 1973 in the east rivers, continuing until 1986. Compared with the runoff before 1969, the decrease of runoff in the upper reaches of the River Ili was less than those in the middle and lower reaches. The decrease in the upper reaches resulted from natural variability, whereas those of the middle and lower reaches were due to a combination of the effects of climate and human activity. There are two reasons for this. First, after 1970, precipitation did not decrease uniformly across the entire basin. Second, in 1970, the Kapchagay dam started operating. As a result, the annual inflow into Lake Balkhash from the River Ili after 1970 decreased to 77% of the pre‐1969 mean. Similarly, after 1973, the inflow from the east rivers was 75% of the pre‐1972 mean.The characteristics of the runoff in the growing season (April to September) and those in the non‐growing season (October to March) were investigated for the upper, middle, and lower reaches of the River Ili. In all reaches, the runoff in the non‐growing season remained unchanged both before and after 1969. However, from 1970 to 1986, decreases of river flow in the growing season were 2·0 to 2·5 times greater in the middle and lower reaches than in the upper reaches. This was primarily due to the impacts of human activity. In conclusion, it can be deduced that the decrease in runoff after 1970 in the middle and lower reaches was the result of human activity during the low‐flow period. Copyright © 2006 John Wiley &amp; Sons, Ltd.

Seasonal Runoff Forecasting Using Precipitation from Meteorological Data Assimilation Systems

In semiarid mountainous regions such as central Asia, runoff from snowmelt often represents the dominant contribution to river flow and freshwater supply during the dry season. The estimation of snow accumulation during the preceding seasons then provides a key to seasonal runoff forecasting with lead times of a few months, and it requires appropriate coverage with surface precipitation and/or snow water equivalent observations. This study tests whether the lack of conventional precipitation and snow observations can be overcome by using model-based precipitation estimates from meteorological data assimilation systems. To this end, a detailed examination is undertaken of the ability of model-assimilated precipitation data to represent the interannual (year-to-year) variations of observed runoff in the Aral Sea basin in central Asia. Precipitation from the 15-yr Re-Analysis (ERA-15) of the European Centre for Medium-Range Weather Forecasts (ECMWF) for the period 1979‐93 is compared against precipitation estimates derived from rain gauge networks, and against the observed natural runoff in the Syrdarya (166 400 km 2) and Amudarya (320 520 km2) basins. It is demonstrated that the ERA-15 dataset is able—despite its low spatial resolution—to describe the seasonal cycle and the larger-scale geographical distribution of precipitation in central Asia. For the Syrdarya basin, it is found that December‐April ERA-15 precipitation correlates well with observed May‐September natural discharge. The correlation coefficient between the two time series amounts to r 5 0.92. It is also demonstrated that ERA-15 precipitation is a better predictor for subsequent runoff than rain gauge‐based precipitation analyses, presumably because of the poor coverage with rain gauge stations. The high correlations suggest that a reliable seasonal runoff forecasting system can be constructed from the statistical relationship between model-assimilated precipitation and subsequent runoff. Cross-validation hindcasting techniques are used to confirm this conclusion. A real runoff forecasting system would, however, require using a real-time precipitation product from an operational data assimilation system. For the Amudarya basin, the correlation between precipitation and subsequent runoff is substantially lower, presumably because of a lower quality of ERA-15 precipitation estimates within the tropical weather system, and/or due to a lower quality of the withdrawal-corrected runoff figures.

Institutional Aspects of Water Management in Central Asia Water Users Associations

The way water resources in the former Soviet Union (FSU) were managed in the second half of the past century had both positive and negative effects and contributed to the existing situation. On the one hand, extensive development of water resources led to the transformation of millions of hectares of virgin lands into agricultural production, providing millions of people with food and livelihoods. On the other hand, the over-exploitation of water resources led to drastic changes of the environment: many water bodies, such as lakes, small rivers, and delta wetlands dried up. The Aral Sea basin is one of the dramatic examples of the negative impacts of large-scale irrigation interventions. The state-controlled era of development in the Soviet period has a legacy of standardized procedures and rules formulated at the top. The shortcomings of such a water management included fragmentation, duplication, and a highly administrative approach without considering the needs of the environment and input of water users into planning, allocating, and managing of water resources. This paper presents an analytical view of the role and importance of water users organizations/associations (WUOs/WUAs) in the irrigated agriculture and under irrigation management transfer (IMT) in Central Asia region. International Water Management Institute (IWMI) and the Scientific Information Center of Interstate Coordination Water Commission (SIC ICWC) conducted the “Best Practices.” Projects including activities covered Syr Darya and Amu Darya basins of Central Asia. During the first stage of the project (01.04.1002-31.03.2002), the monitoring objects were: 30 district water management organizations (DWMO), eight WUAs, 58 collective farms (CCF), and 61 private farms (PPF) from eight provinces Central Asia) project for conserving water resources by involving water users into water savings. The primary strategy was to propagate application of inexpensive technical and managerial methods and measures to save water by users themselves. The project is a joint project of IWMI and SIC ICWC aimed to monitor and disseminate the best practices of water conservation initiated by water users. The first year of the “Best Practices” project accomplished a broader involvement of water users into the water conserving methods, therefore continuing the beneficial good water management practices. It also continued to involve the water supplying organizations and various groups of water users (collective farms, farmers, and water users' associations). The major interest was to analyze the impacts of the different water conservation and management practices on productivity of water use.