Agricultural Adaptation to Reconcile Food Security and Water Sustainability Under Climate Change: The Case of Cereals in Iran

• Published in: Earth's future Vol. 10; no. 9; pp. e2021EF002095 - n/a
• Main Authors: Karandish, Fatemeh, Nouri, Hamideh, Schyns, Joep F.
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01-09-2022; John Wiley and Sons Inc
• Subjects: Abrupt/Rapid Climate Change; Adaptation; Agricultural land; Agricultural production; Agricultural Systems; Agriculture; Air/Sea Constituent Fluxes; Air/Sea Interactions; Arid regions; Arid zones; Atmospheric; Atmospheric Composition and Structure; Atmospheric Effects; Atmospheric Processes; Avalanches; Barley; Benefit‐cost Analysis; Biogeosciences; Cereals; climate adaptation; Climate and Interannual Variability; Climate change; Climate Change and Variability; Climate Dynamics; Climate Impact; Climate Impacts; Climate Variability; Climatology; Computational Geophysics; Corn; Crop yield; Crops; Cryosphere; Decadal Ocean Variability; Disaster Risk Analysis and Assessment; Drought; Earth System Modeling; Earthquake Ground Motions and Engineering Seismology; Effusive Volcanism; Explosive Volcanism; Food security; Food supply; Freshwater resources; Future climates; General Circulation; Geodesy and Gravity; Geological; Global Change; Global Change from Geodesy; Gravity and Isostasy; Hydrological Cycles and Budgets; Hydrology; Impacts of Global Change; Informatics; Land/Atmosphere Interactions; Marine Geology and Geophysics; Mass Balance; Modeling; Mud Volcanism; Natural Hazards; Numerical Modeling; Numerical Solutions; Ocean influence of Earth rotation; Ocean Monitoring with Geodetic Techniques; Ocean/Atmosphere Interactions; Ocean/Earth/atmosphere/hydrosphere/cryosphere interactions; Oceanic; Oceanography: General; Oceanography: Physical; Oceans; Paleoceanography; Physical Modeling; Policy Sciences; Precipitation; Preparedness and Planning; Productivity; Provinces; Radio Oceanography; Radio Science; Regional Climate Change; Regional Modeling; Regional Planning; Rice; Risk; Sea Level Change; Sea Level: Variations and Mean; Seasons; Seismology; Solid Earth; Surface Waves and Tides; Theoretical Modeling; Tsunamis and Storm Surges; Volcanic Effects; Volcanic Hazards and Risks; Volcano Monitoring; Volcano Seismology; Volcano/Climate Interactions; Volcanology; Water consumption; Water Cycles; water footprint; Water Management; water productivity; Water resources; Water scarcity; Water Supply; Water use; Wheat; Iran; water scarcity; water footprint; water productivity; climate adaptation; food security; climate change
• ISSN: 2328-4277; 2328-4277
• DOI: 10.1029/2021EF002095

In this study, we simulate the crop yield and water footprint (WF) of major food crops of Iran on irrigated and rainfed croplands for the historical and the future climate. We assess the effects of three agricultural adaptation strategies to climate change in terms of potential blue water savings. We then evaluate to what extent these savings can reduce unsustainable blue WF. We find that cereal production increases under climate change in both irrigated and rainfed croplands (by 2.6–3.1 and 1.4–2.3 million t yr−1, respectively) due to increased yields (6.6%–78.7%). Simultaneously, the unit WF (m3 t−1) tends to decrease in most scenarios. However, the annual consumptive water use increases in both irrigated and rainfed croplands (by 0.3–1.8 and 0.5–1.7 billion m3 yr−1, respectively). This is most noticeable in the arid regions, where consumptive water use increases by roughly 70% under climate change. Off‐season cultivation is the most effective adaptation strategy to alleviate additional pressure on blue water resources with blue water savings of 14–15 billion m3 yr−1. The second most effective is WF benchmarking, which results in blue water savings of 1.1–3.5 billion m3 yr−1. The early planting strategy is less effective but still leads to blue water savings of 1.7–1.9 billion m3 yr−1. In the same order of effectiveness, these three strategies can reduce blue water scarcity and unsustainable blue water use in Iran under current conditions. However, we find that these strategies do not mitigate water scarcity in all provinces per se, nor all months of the year.
Key Points
Replacing irrigated by rainfed cereals has the highest potential in saving blue water
Benchmarking water footprints and early‐planting have promising, but lower effects
The adaptation strategies cannot mitigate water scarcity in all provinces/months