The water-energy-food (WEF) nexus is a holistic concept used to understand the synergies and trade-offs of interdependent water, energy, and food resources. Despite its widespread use, this concept often overlooks environmental concerns. In addition, the lack of a systemic approach in the Aral Sea Basin (ASB) has resulted in serious environmental degradation. For instance, the Aral Sea, situated at the terminus of the basin, is steadily shrinking, yet researchers studying the WEF nexus tend to overlook the upstream tributaries of the basin. This study aims to determine the extent to which research on the WEF nexus in the ASB in Central Asia has considered the environment through a systematic review of the literature published between 2012 and 2022. The results indicate that the number of WEF publications regarding the ASB has seen an upward trend, with a primary focus on the transboundary level and less research available on the local and national levels. This confirms the strong reliance of Central Asian states on one another for food, energy, and water resources. Furthermore, the results show that the majority of published studies either do not consider environmental concerns in their analyses at all or do so with little precision. Therefore, to achieve precise and sustainable outcomes, this study recommends the inclusion of environmental concerns along with basin-wide coverage in future WEF analyses. Finally, the WEF concept should be downscaled to the national and local levels in order to facilitate its implementation.

The water-energy-food (WEF) nexus is a holistic concept used to understand the synergies and trade-offs of interdependent water, energy, and food resources. Despite its widespread use, this concept often overlooks environmental concerns. In addition, the lack of a systemic approach in the Aral Sea Basin (ASB) has resulted in serious environmental degradation. For instance, the Aral Sea, situated at the terminus of the basin, is steadily shrinking, yet researchers studying the WEF nexus tend to overlook the upstream tributaries of the basin. This study aims to determine the extent to which research on the WEF nexus in the ASB in Central Asia has considered the environment through a systematic review of the literature published between 2012 and 2022. The results indicate that the number of WEF publications regarding the ASB has seen an upward trend, with a primary focus on the transboundary level and less research available on the local and national levels. This confirms the strong reliance of Central Asian states on one another for food, energy, and water resources. Furthermore, the results show that the majority of published studies either do not consider environmental concerns in their analyses at all or do so with little precision. Therefore, to achieve precise and sustainable outcomes, this study recommends the inclusion of environmental concerns along with basin-wide coverage in future WEF analyses. Finally, the WEF concept should be downscaled to the national and local levels in order to facilitate its implementation.

The widespread uncertainty regarding future changes in climate, socioeconomic conditions, and population growth have increased interest in water-energy-food-ecology nexus-based frameworks in relation to the analysis of water resources. A challenge for modeling the water-energy-food-ecology nexus is how to reduce the multidimensional and codependent uncertainties and measure the complicated casual relationships effectively. We propose a methodological solution to the problem, and this solution is demonstrated in this case as an extension to the previous water resource optimization framework. We coupled the water-energy-food-ecology nexus into the Bayesian network, which provides a formal representation of the joint probabilistic behavior of the system, and the method was applied to water resource use analysis and management in the Syr Darya River basin, a transboundary and endorheic basin that has contributed to the Aral Sea ecological crisis as a result of unreasonable water use. The annual scale data of four periods, 1970–1980, 1980–1991, 1991–2005, and 2005–2015, were introduced into the Bayesian network. Before the disintegration of the Soviet Union, the amount of water inflow into the Aral Sea was sensitive to increases in irrigation for agricultural development, increases in water storage of the upstream reservoirs and stochastic runoff. After the disintegration of the Soviet Union, the amount of water inflow into the Aral Sea was sensitive to the inefficient irrigation water use in the downstream areas of Uzbekistan and Kazakhstan and the water storage of the reservoir located upstream of Kyrgyzstan. The change resulted from unresolvable disputes between water use for power generation in the upstream area and irrigation in the downstream area. Comprehensive scenario analysis shows that, in the short term, it would be useful to improve the proportion of food crops, improve the efficiency of water use in relation to salt leaching and irrigation, and prevent drought damage. In the long term, based on the increased use of advanced drip irrigation technology from 50% to 80%, the annual inflow into the Aral Sea will increase significantly, reaching 6.4 km³ and 9.6 km³, respectively, and this technology is capable of ameliorating the ecological crisis within the basin.

In today’s intrinsically connected world, the Water–Food–Energy–Climate Nexus (WFEC Nexus) concept provides a starting point for informed and transparent decision-making based on the trade-offs and synergies between different sectors, including aquatic ecosystems, food security, energy production, and climate neutrality. The WFEC Nexus approach is particularly applicable in regions requiring transboundary water management, such as Central Asia. Unfortunately, this region with unevenly distributed water resources—consisting of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan—is characterized by data scarcity, which limits informed decision-making. However, open-source geodata is becoming increasingly available. This paper aims to fill Central Asia’s WFEC Nexus data gap by providing an overview of key data. We collected geodata through an integrated survey of stakeholders and researchers, stakeholder consultation, and literature screening. Sixty unique datasets were identified, belonging to one of six thematic categories: (1) climate, (2) hydrology, (3) geography and topography, (4) geomorphology, (5) ecology, and (6) anthropogenic uses. For each dataset, a succinct description, including a link to the online source, is provided. We also provide possible applications of using the presented datasets, demonstrating how they can assist in conducting various studies linked to the WFEC Nexus in Central Asia and worldwide.

A copula bi-level fractional programming (CBFP) method is developed for planning the water–food–energy–ecology (WFEE) nexus system. CBFP has advantages in (i) dealing with ratio-objective problems, (ii) balancing the conflicts between hierarchical decision levels, and (iii) reflecting joint risks of correlated uncertain variables. Then, a CBFP–WFEE model is formulated to the Ili-Balkhash basin in Central Asia, in which 108 scenarios associated with different irrigation efficiencies, ecological-flow demands (EBW), and water–land resources have been examined. Solutions of water allocation, hydropower generation, and land-use pattern are obtained. Our major findings are as follows: (i) from 2021 to 2050, water allocation to livestock in East Kazakhstan would remarkably increase (by 40.9%) when water allocation to food is satisfied; (ii) hydropower generation would increase with the rising ecological flows and arable land resources; (iii) EBW is the key factor influencing the water inflow to the Balkhash Lake; (iv) the share of ecosystem water allocation would exceed 17.5% by 2050, and grassland area would rank in the first place of the ecosystem. Compared with conventional bi-level stochastic programming and single-level fractional programming models, the CBFP–WFEE model can achieve a higher ecosystem service value and higher efficiency of water–land resources, which can provide more feasible and sustainable alternatives for the WFEE nexus system. The obtained results can help balance the contradictions among water shortage, economic development, and ecology protection, as well as provide synergic management strategies for regional sustainability.

Thoroughly understanding the security of water, energy and food (WEF) and the factors that influence them is essential for sustainable development management in any region. This study proposed a new analytical framework for WEF security evaluation in both individual sectors and the whole system, using the technique for order preference by similarity to an ideal solution (TOPSIS) and four dimensions of security indicators: availability, self-sufficiency, productivity and accessibility. The internal relationships among the three sectors and the main factors influencing WEF security were analysed by Spearman’s rank correlation and radar graphs, respectively. The five countries in Central Asia (CA), which are experiencing WEF crises and facing great challenges in achieving their sustainable development goals (SDGs), were chosen as a case study in this paper. Our results showed that Kazakhstan attained the highest WEF security level, followed by Kyrgyzstan, Turkmenistan and Uzbekistan; Tajikistan exhibited the lowest security level from 2000 to 2014. Three types of internal relationships among the three sectors were identified: synergies, trade-offs and unclassified. The unclassified relationship type accounted for the largest share of 54% in CA, suggesting great potential for synergetic improvement among the three sectors. Approaches for improving the country WEF security based on our research are as follows: Kazakhstan should prioritize food allocation and supply, Kyrgyzstan and Tajikistan should increase energy and food production and raise the supply level and usage efficiency of water and food, Turkmenistan should increase the available water resources and food production and improve the supply level and usage efficiency of water and energy, and Uzbekistan should both increase the available amount and enhance the WEF management performance.