To meet the food demand of a growing global population, agricultural production will have to more than double in this century. Agricultural land expansion combined with yield increases will therefore be required. This thesis investigates whether enough water resources will be available to sustain the future food production. Using a global scale hydrology and crop growth model, the combined effect of climate change and socio economic changes on water scarcity and food production were quantified. The first thing to explore was where water for agriculture is currently extracted. Reservoirs behind large dams are found to be very important for agriculture and contribute around 18% of the total irrigation water today. It is shown however that with current reservoir capacities and irrigation efficiencies, not enough water can be supplied to sustain an increased food production. Irrigation water shortage can lead to a loss of 20% of the irrigated crop production globally, but with important regional differences. Regions particularly at risk include basins in Southern Africa and South Asia, where production losses on irrigated cropland can become over 50%. This means that unless major investments are made towards improving irrigation efficiency and increasing storage capacity, water shortage will put a serious constraint on future food production.

This is a discussion of the issues surrounding water resource development and management in South Asia, namely, which innovative approaches and methodologies can help resolve the deadlock in water resources development and management?

To meet the food demand of a growing global population, agricultural production will have to more than double in this century. Agricultural land expansion combined with yield increases will therefore be required. This thesis investigates whether enough water resources will be available to sustain the future food production. Using a global scale hydrology and crop growth model, the combined effect of climate change and socio economic changes on water scarcity and food production were quantified. The first thing to explore was where water for agriculture is currently extracted. Reservoirs behind large dams are found to be very important for agriculture and contribute around 18% of the total irrigation water today. It is shown however that with current reservoir capacities and irrigation efficiencies, not enough water can be supplied to sustain an increased food production. Irrigation water shortage can lead to a loss of 20% of the irrigated crop production globally, but with important regional differences. Regions particularly at risk include basins in Southern Africa and South Asia, where production losses on irrigated cropland can become over 50%. This means that unless major investments are made towards improving irrigation efficiency and increasing storage capacity, water shortage will put a serious constraint on future food production.

Afghanistan is a headwater state that contributes supplies to several countries in Central and South Asia. However, despite being a water source, it faces the challenge of establishing its own storage infrastructure and water-sharing methods to protect its food security. This article investigates impacts on the Afghan agricultural sector resulting from enhanced reservoir storage capacity and better-performing water-sharing methods. An integrated systems analysis is formulated to analyze the economic performance of both interventions. Results reveal that both interventions show the highest capacity to improve food security in conditions where water supply shows the greatest natural fluctuations.

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.

With the increasing population and accelerated urbanization, demands for water are rising for different sectors around the world, including in South Asia. Integrated water resource management (IWRM) offers a promising potential to address multifaceted water demands. This study therefore aimed to address this issue by (i) reviewing key issues related to water, land, and food in South Asian countries, (ii) exploring the prevalent irrigation management strategies in those countries, and (iii) examining the IWRM situation based on a Nepalese case study, and it proposes some options to support effective implementation of IWRM. South Asia, the home to 24% of the world's population with only 15% and 7% of the world's arable and permanent crop land and water resources, respectively, is the worst‐affected region in the world from undernourishment. Surface irrigation is the dominant irrigation application method in the region, which incurs high water losses due to the lack of flexible water control structures in canal networks. The Nepalese case study revealed a lack of clear institutional arrangements to implement IWRM and disparate and conflicting views about IWRM. Creation and strengthening of basin‐level water user organizations, technological improvements, and awareness‐raising activities are some potential ways forward to implement IWRM.

PR | IFPRI3; ISI; Environment and Natural Resource Management | EPTD | Journal article