The water-energy-food nexus (“nexus”) is promoted as an approach to look at the linkages between water, energy and food. The articles of Water’s Special Issue “Water-Energy-Food Nexus in Large Asian River Basins” look at the applicability of the nexus approach in different regions and rivers basins in Asia. The articles provide practical examples of the various roles and importance of water-energy-food linkages, but also discuss the theoretical aspects related to the nexus. While it is evident that any application of the nexus must be case-specific, some general lessons can be learnt as well. Firstly, there are a variety of interpretations for the nexus. These include three complementary perspectives that see nexus as an analytical approach, governance framework and emerging discourse. Secondly, nexus is—despite its name—a predominantly water-sector driven and water-centered concept. While this brings some benefits by, e.g., setting systemic boundaries, it is also the nexus’ biggest challenge: If the nexus is not able to ensure buy-in from food and energy sector actors, its added value will stay limited. Ultimately, however, what really matters is not the approach itself but the processes it helps to establish and outcomes it helps to create. Through its focus on water-energy-food linkages—rather than on those themes separately—the nexus is well positioned to help us to take a more systemic view on water, energy and food and, hence, to advance sustainable development.

This article examines impacts of infrastructure development and climate variability on economic outcomes for the Amu Darya Basin in Central Asia. It aims to identify the most economically productive mix of expanded reservoir storage for economic benefit sharing to occur, in which economic welfare of all riparians is improved. Policies examined include four combinations of storage infrastructure for each of two climate futures. An empirical optimization model is developed and applied to identify opportunities for improving the welfare of Tajikistan, Uzbekistan, Afghanistan, and Turkmenistan. The analysis 1) characterizes politically constrained and economically optimized water-use patterns for these combinations of expanded reservoir storage capacity, 2) describes Pareto-Improving packages of expanded storage capacity that could raise economic welfare for all four riparians, and accounts for impacts for each of two climate scenarios. Results indicate that a combination of targeted water storage infrastructure and efficient water allocation could produce outcomes for which the discounted net present value of benefits are favorable for each riparian. Results identify a framework to provide economic motivation for all riparians to cooperate through development of water storage infrastructure. Our findings illustrate the principle that development of water infrastructure can expand the negotiation space by which all communities can gain economic benefits in the face of limited water supply. Still, despite our optimistic findings, patient and deliberate negotiation will be required to transform potential improvements into actual gains.

The excessive water use in Central Asian countries has caused an environmental disaster in the Aral Sea. In this regard, they need to improve the efficiency of the use of shared water resources to overcome their environmental and economic difficulties. Accordingly, the twin objectives of this study were firstly to analyse the challenges for the use of water resources in the Aral Sea Basin and secondly to estimate the agricultural water use efficiency according to the crop types and irrigation methods. The results showed that the economic efficiency of water use in Central Asian countries was lower than that of other Asian countries. Finally, this study illustrated that the selection of crop types and irrigation methods can improve the quantitative and economic efficiency of water use. However, a clear preliminary outline of interactions is necessary to avoid failure of coordination and collaboration for a regional win-win approach. In such an outline, this study will deliver valuable information on water efficiency in the Aral Sea basin.

According to the UN, the population of Central Asia will increase from its current approximately 65million people to a well over 90million by the end of this century. Taking this increasing population into consideration, it is impossible to project development strategies without considering three key factors in meeting the demands of a growing population: water, food and energy. Societies will have to choose, for instance, between using land and fertilizer for food production or for bio-based or renewable energy production, and between using fresh water for energy production or for irrigating crops. Thus water, food and energy are inextricably linked and must be considered together as a system. Recently, tensions among the Central Asian countries over the use of water for energy and energy production have increased with the building of Rogun Dam on the Vakhsh River, a tributary of the Amu Darya River. The dam will provide upstream Tajikistan with hydropower, while downstream countries fear it could negatively impact their irrigated agriculture. Despite recent peer reviewed literature on water resources management in Amu Darya Basin, none to date have addressed the interconnection and mutual impacts within water–energy–food systems in face of constructing the Rogun Dam. We examine two potential operation modes of the dam: Energy Mode (ensuring Tajikistan’s hydropower needs) and Irrigation Mode (ensuring water for agriculture downstream). Results show that the Energy Mode could ensure more than double Tajikistan’s energy capacity, but would reduce water availability during the growing season, resulting in an average 37% decline in agricultural benefits in downstream countries. The Irrigation Mode could bring a surplus in agricultural benefits to Tajikistan and Uzbekistan in addition an increasing energy benefits in Tajikistan by two fold. However, energy production in the Irrigation Mode would be non-optimally distributed over the seasons resulting in the most of hydropower being produced during the growing season. Neither operation mode provides optimal benefits for all the countries, emphasizing how difficult it is to actually reach a win–win scenario across the water–energy–food security nexus in transboundary river basins.

In Central Asia, more than 90 % of annually renewable water resources are consumptively utilized in irrigation, and allocation conflicts between large-scale hydropower in the upstream and irrigation in the downstream occur regularly and mostly across complex international borders, especially during water scarce years and low storage conditions. With increasing attention on climate-neutral hydropower solutions, including on small-scale hydropower. An abstract submitted to the EGU General Assembly 2022.

This paper focuses on regional integration through the lenses of the Water–Food–Energy (WEF) nexus, a concept putting strong emphasis on cross-sectoral and multi-level interactions as well as on resource interdependencies. There is an extensive amount of published research focusing on the Aral Sea basin. In this paper, the authors build upon these different contributions and provide a meta-analysis of the literature of WEF nexus opportunities in Central Asia (CA) countries. This paper contributes to ongoing discussions regarding how the WEF Nexus can represent an opportunity for reinforced collaboration regarding resources management. To do so, focusing on existing literature, this paper first (1) explores how the nexus can be a relevant instrument for regional integration. Second (2), it provides an overview of water, food, energy conditions and challenges in the Aral Sea basin in particular. Third (3), synthesizing existing research, the authors identify critical variables to be considered as hurdles or leverage points for WEF nexus implementation in the Aral Sea basin. Finally (4), we go back to our initial set of questions and identify some possible avenues for future research.

In Central Asia, more than 90 % of annually renewable water resources are consumptively utilized in irrigation, and allocation conflicts between large-scale hydropower in the upstream and irrigation in the downstream occur regularly and mostly across complex international borders, especially during water scarce years and low storage conditions. With increasing attention on climate-neutral hydropower solutions, including on small-scale hydropower. An abstract submitted to the EGU General Assembly 2022.

The water-energy-food nexus is a topical subject for research and practice, reflecting the importance of these sectors for humankind and the complexity and magnitude of the challenges they are facing. While the nexus as a concept is not yet mature or fully tested in practice, it has already encouraged a range of approaches in a variety of contexts. This article provides a set of definitions recognizing three perspectives that see the nexus as an analytical tool, governance framework and as an emerging discourse. It discusses the implications that an international transboundary context brings to the nexus and vice versa. Based on a comparative analysis of three Asian regions—Central Asia, South Asia and the Mekong Region—and their related transboundary river basins, we propose that the transboundary context has three major implications: diversity of scales and perspectives, importance of state actors and importance of politics. Similarly, introducing the nexus as an approach in a transboundary context has a potential to provide new resources and approaches, alter existing actor dynamics and portray a richer picture of relationships. Overall, the significance of water-energy-food linkages and their direct impacts on water allocation mean that the nexus has the potential to complement existing approaches also in the transboundary river basins.

The water-energy-food nexus is a topical subject for research and practice, reflecting the importance of these sectors for humankind and the complexity and magnitude of the challenges they are facing. While the nexus as a concept is not yet mature or fully tested in practice, it has already encouraged a range of approaches in a variety of contexts. This article provides a set of definitions recognizing three perspectives that see the nexus as an analytical tool, governance framework and as an emerging discourse. It discusses the implications that an international transboundary context brings to the nexus and vice versa. Based on a comparative analysis of three Asian regions—Central Asia, South Asia and the Mekong Region—and their related transboundary river basins, we propose that the transboundary context has three major implications: diversity of scales and perspectives, importance of state actors and importance of politics. Similarly, introducing the nexus as an approach in a transboundary context has a potential to provide new resources and approaches, alter existing actor dynamics and portray a richer picture of relationships. Overall, the significance of water-energy-food linkages and their direct impacts on water allocation mean that the nexus has the potential to complement existing approaches also in the transboundary river basins.