Improving water use efficiency in agronomic crop production

Abstract

Food and agriculture are the largest consumers of water, requiring one hundred times more than we use for personal needs. Agricultural water is used to grow fresh produce and sustain livestock. Agriculture is expected to face increasing water risks that will impact production, markets, trade, and food security - risks that can be mitigated with targeted policy. Water resource management is the activity of planning, developing, distributing, and managing the optimum use of water resources. Water use efficiency (WUE) refers to the ratio of water used in plant metabolism to water lost by the plant transpiration. WUE can also be improved through different methods such as irrigation scheduling and on-farm water management. Irrigation scheduling is the decision of when and how much water to apply to a field. Its purpose is to maximize irrigation efficiencies by applying the exact amount of water needed to replenish the soil moisture to the desired level. It enables the farmers to schedule water rotation among the various fields to minimize crop water stress and maximize yields. It reduces the farmer’s cost of water and labor through less irrigation, thereby making maximum use of soil moisture storage. This chapter reviews the main linkages between climate change, water, and agriculture as a means to identifying and discussing adaptation strategies for better use and conservation of water resources.