Impacts of climate change on agricultural water management: a review

This study provides an overview on the impacts of climate change on agricultural water management, including agricultural water requirement, water availability and water quality, and the transition of those impacts to crop yield, agricultural land suitability and livestock production systems, considering both long-term trends of climate and extreme climatic events. A synthesis of findings from local, regional, and global studies guides this article's discussion of scientifically based information, implications for managing the risk of water scarcity and food insecurity, and future research. Negative and positive climate change impacts occurring at the local scale may counteract each other at the global scale (e.g., those on irrigation requirement and arable land availability); the impacts from the various factors can be counter-balanced too (e.g., CO2 and water deficit impact on crop yield). Meanwhile, the shocks at the local and regional levels have been or will be caused by water quantity and quality problems and are pressing concerns for decision making. Although uncertainty in climate change predictions remains a critical issue for decision making, certain knowledge about the impact on crop production has been obtained from historical data. Finally, future research needs to focus on gaining a more detailed understanding of climate change (especially extreme events), climate change impacts, both natural and social response mechanisms, and adaptation measures of agricultural water management. More focus should be laid on improving impact assessment via the various methods such as retrospective analysis, monitoring, prediction, and strategic risk management. Moreover, planned adaptations in agricultural water management will be needed to facilitate more consistent and more effective responses to climate change, with consideration of the linkage with nonagricultural water uses. (C) 2015 Wiley Periodicals, Inc.