Improved Irrigation Efficiency as a Tool for Climate Change Adaptation in Arid Environments

摘要

Potential changes in irrigation efficiency were investigated to assess their impact on agricultural and urban water demand in the Rio Grande basin in Jujuy province, Argentina, over the 50-year period from 2010 to 2060 within the context of three climate change scenarios derived from the Fourth Assessment of the Intergovernmental Panel on Climate Change and applied to two Global Circulation Models. The basin is an arid region that suffers from water scarcity, seasonal shortages and competition amongwater users, including urban, agriculture, food processing, and hydropower. The case-study evaluated feasible improvements in the efficiency of irrigation water systems to determine whether water savings from such improvements would be sufficient to off-set anticipated growth in water demand. This study is an attempt to contribute to the broader assessment of applying the principles of 'climate-smart agriculture' to arid, water scarce environments, and correlates the improvement in water efficiency to two other objectives: achieving equal or greater agricultural yields of current crops; and mitigating the ecological damage caused by traditional, extensive agricultural regimes . This paper focuses on two potential irrigation interventions providing irrigation efficiency greater or equal to 60% and the baseline ('no-intervention') option using reference transpiration derived from CROPWAT calculations based on five decadal climate projections for sugar cane and tobacco and suggests that improved irrigation efficiency is a critical intervention for climate change adaptation. Irrigation efficiency is one of the major component tools of 'climate-smart agriculture'