Determining the dynamics of agricultural water use: cases from Asia and Africa

Across Africa and Asia water resources are being affected by a complex mixture of social, economic, and environmental factors. These include climate change and population growth, food prices,oil prices, financial disruptions, and political fluctuations. The need to produce more food will have one of the largest impacts on water and will continue to re-shape the patterns of agricultural water use in major food-growing regions.With this increasing demand on water for agriculture, from large-scale irrigation to intensification of rainfed systems, it is becoming increasingly important to ensure that water resources decision-making has access to information that captures the spectrum of water uses, across seasons, and over time. Furthermore, the major sectors that place demands on water and otherwise affect the resource need water-related information to inform their decisions. In this paper we consider two cases where the range of agricultural water management uses have been examined. We examine the methodologies and approaches used, the utility of this information to decision-making in the water and agricultural sectors, and the limitations of the information gathered.