Abstract
Demographic growth, changes in diet, and reliance on first-generation biofuels are increasing the human demand for agricultural products, thereby enhancing the human pressure on global freshwater resources. Recent research on the food-water nexus has highlighted how some major agricultural regions of the world lack the water resources required to sustain current growth trends in crop production. To meet the increasing need for agricultural commodities with limited water resources, the water use efficiency of the agricultural sector must be improved. In this regard, recent work indicates that the often overlooked strategy of changing the crop distribution within presently cultivated areas offers promise. Here we investigate the extent to which water in the United States could be saved while improving yields simply by replacing the existing crops with more suitable ones. We propose crop replacement criteria that achieve this goal while preserving crop diversity, economic value, nitrogen fixation, and food protein production. We find that in the United States, these criteria would greatly improve calorie (+46%) and protein (+34%) production and economic value (+208%), with 5% water savings with respect to the present crop distribution. Interestingly, greater water savings could be achieved in water-stressed agricultural regions of the US such as California (56% water savings), and other western states.
Highlights
The increasing demand for agricultural commodities resulting from demographic growth, economic development, urbanization, and the use of first-generation biofuels is placing an unprecedented pressure on global water resources (e.g., [1,2,3,4])
Despite only modest improvements at the national scale, our results showed that certain water-scarce agricultural regions have the potential to achieve substantial reductions in water use by optimizing cropping patterns (Figure 2).at
Previous studies have highlighted the possible existence of strong inefficiencies in water use by agriculture
Summary
The increasing demand for agricultural commodities resulting from demographic growth, economic development, urbanization, and the use of first-generation biofuels is placing an unprecedented pressure on global water resources (e.g., [1,2,3,4]). With many areas around the world facing chronic water stress because of excessive withdrawals from surface and groundwater bodies [4], there is a widespread concern that in the few decades, hydrologic conditions will severely limit food production [5]. These concerns arise after decades of sustained increase in global crop production afforded by the technological innovations of the industrial and green revolutions, such as modern machinery, industrial fertilizers, irrigation pumps, and new cultivars (e.g., [6,7]). Other approaches to agricultural intensification do not necessarily aim at yield gap closure but use multiple growing seasons (“harvest gap closure”) in regions with suitable climate conditions to increase the annually harvested cropland [18]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
