Minimizing irrigation water demand: An evaluation of shifting planting dates in Sri Lanka
Climate change coupled with increasing demands for water necessitates an improved understanding of the water–food nexus at a scale local enough to inform farmer adaptations. Such assessments are particularly important for nations with significant small-scale farming and high spatial variability in climate, such as Sri Lanka. By comparing historical patterns of irrigation water requirements (IWRs) to rice planting records, we estimate that shifting rice planting dates to earlier in the season could yield water savings of up to 6%. Our findings demonstrate the potential of low-cost adaptation strategies to help meet crop production demands in water-scarce environments. This local-scale assessment of IWRs in Sri Lanka highlights the value of using historical data to inform agricultural management of water resources when high-skilled forecasts are not available. Given national policies prioritizing in-country production and farmers’ sensitivities to water stress, decision-makers should consider local degrees of climate variability in institutional design of irrigation management structures.
KeywordsClimate change adaptation Crop production Food security Irrigation water requirements Planting dates Water resources management
This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program [Grant No. DGE-0909667] and by the Water, Sustainability, and Climate program [Grant No. NSF-EAR 1204685]. These funding sources had no impact on research design, data interpretation, or in the writing of the report.
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