Accounting for socioeconomic constraints in sustainable irrigation expansion assessments

Abstract

Sustainable irrigation expansion over water limited croplands is an important measure to enhance agricultural yields and increase the resilience of crop production to global warming. While existing global assessments of irrigation expansion mainly illustrate the biophysical potential for irrigation, socioeconomic factors such as weak governance or low income, that demonstrably impede the successful implementation of sustainable irrigation, remain largely underexplored. Here we provide five scenarios of sustainable irrigation deployment in the 21st century integrated into the framework of Shared Socioeconomic Pathways, which account for biophysical irrigation limits and socioeconomic constraints. We find that the potential for sustainable irrigation expansion implied by biophysical limits alone is considerably reduced when socioeconomic factors are considered. Even under an optimistic scenario of socio-economic development, we find that additional calories produced via sustainable irrigation by 2100 might reach only half of the maximum biophysical potential. Regions with currently modest socioeconomic development such as Sub-Saharan Africa are found to have the highest potential for improvements. In a scenario of sustainable development, Sub-Saharan Africa would be able to almost double food production and feed an additional 70 million people compared to 2020, whereas in a scenario where regional rivalry prevails, this potential would be halved. Increasing sustainable irrigation will be key for countries to meet the projected food demands, tackle malnutrition and rural poverty in the context of increasing impacts of anthropogenic climate change on food systems. Our results suggest that improving governance levels for example through enhancing the effectiveness of institutions will constitute an important leverage to increase adaptive capacity in the agricultural sector.

Solutions to agricultural green water scarcity under climate change

“…2 ). Expanding irrigation might not be a feasible solution over these croplands considering socioeconomic trade-offs between increased agricultural productivity and capital and operational costs of new irrigation systems ( 46 ). However, adopting nature-based agricultural practices with appropriate low-cost land and water management can help retain more green water in the soil by reducing soil evaporation ( 30 , 47 ).…”

“…However, in areas with physically available renewable blue water resources, irrigation can be blocked by a variety of socioeconomic and political factors that cause the so-called agricultural economic water scarcity ( 6 ). These regions tend to lack the capacity to afford the costs to develop irrigation infrastructure using the available renewable blue water resources ( 6 , 46 ).…”

Representation of adaptation in quantitative climate assessments

“…This framework can capture socioeconomic dimensions related to adaptive capacity, such as gross domestic product per capita, education and governance (M.A., manuscript in preparation). Representation of adaptive capacity within the SSPs has been demonstrated by developing projections for adaptation options in different sectors, such as air-conditioning 15 and sustainable irrigation 16 . However, sectoral applications are limited and do not provide a comprehensive cross-sectoral assessment of adaptation.…”

Future Food Security in Africa Under Climate Change

“…Additionally, improving socio‐economic conditions (i.e., empowering women, reducing the gender gap), investing in infrastructure, and sustainably intensifying food production are essential interventions to improve availability and demand ratios (FAO, ECA and AUC, 2021; Graves et al., 2019; van Maanen et al., 2022). The intensification of food production, however, may strongly affect rural livelihoods, as small‐holder farmers have more limited access to credit and financial resources to invest in high yield technology (e.g., irrigation, fertilizers, mechanization, concentrated livestock systems) and are therefore more likely to be displaced by agribusiness corporations.…”