Water is an essential resource for agriculture and food production, which plays a critical role in global food security. Agriculture is the largest consumer of freshwater resources globally, accounting for 72% of total annual freshwater withdrawals, according to the World Bank (2019a). The share of agricultural water use varies significantly across regions and countries, with South Asia having the largest share of agricultural water use (91%), while the European Union has the smallest (31%). Among countries with the largest agricultural production, the share of agricultural water use is highest in India (90%), followed by China (64%), Brazil (61%), and the United States (40%) (World Bank, 2019b).
The absolute demand for water will remain much higher in agriculture in the next two decades due to the necessity of satisfying food demand for the rising global population, which is projected to increase from over 7 billion people in 2017 to around 10 billion people in 2050 (United Nations, 2022). With higher economic growth in developing countries, per capita food demand growth is more likely to be a driving factor behind food demand in 2050 compared to population growth alone. To meet the extra food demand in 2050, global production of crops and livestock is estimated to be at least 60% higher than it was in 2006 (van Dijk et al., 2021). However, the impacts of climate change on water resource availability and its spatial distributions pose significant challenges to the global food supply, despite new advancements in farming practices and innovations in agricultural systems.
The major challenges in agricultural water resource management include the unsustainable use of water in irrigation, unsustainable consumption of water in food systems, climate change, and inadequate institutional policies. These challenges have severe implications for future food and water security. For example, irrigated agriculture is highly unsustainable, with almost 52% of global irrigation considered unsustainable, and the depletion of freshwater stocks and environmental flows leading to unsustainable use of water (Rosa et al., 2019). Increases in the purchasing power associated with economic growth and urbanization have also led to an increase in the production of livestock in many countries, thereby increasing pressure on water resources (Rahut et al., 2022). Climate change has considerably affected the available water for agriculture and contributed to water-related hazards such as floods and droughts, limiting the agriculture sector's capacity to ensure food security unless water management issues are addressed. Existing institutional policies, both at the national and international levels, cannot adequately address agricultural water management to secure future water and food security (FAO, 2017a).
There are opportunities to address the challenges and ensure future food and water security through various interventions. These interventions include improving water use efficiency in agriculture, such as by promoting precision irrigation and water-saving technologies, improving the sustainability of food production systems, such as by reducing food waste and shifting towards more sustainable and diversified diets, and enhancing institutional policies and governance for sustainable water management. For example, the adoption of modern irrigation technologies and practices such as drip irrigation, fertigation, and mulching can significantly reduce water use in agriculture and increase water use efficiency (FAO, 2021a). Similarly, reducing food waste and shifting towards more plant-based diets can reduce the overall demand for water in food production and promote sustainable use of water resources (Springmann et al., 2018).
In conclusion, agriculture accounts for the largest share of global freshwater withdrawals, with significant regional and country-level variations. The absolute demand for water in agriculture is expected to remain high due to the rising global population and increasing per capita food demand, leading to challenges in agricultural water resource management that have implications for future food and water security. However, there are also opportunities to improve water resource management in agriculture, such as promoting sustainable practices and increasing collaboration between different stakeholders. Addressing these challenges and embracing these opportunities will be essential for ensuring a sustainable and secure future for food and water resources globally.
References
Boretti, A., & Rosa, L. (2019). Water, food, and population dynamics. Journal of environmental management, 232, 858-868.
Food and Agriculture Organization. (2017a). The future of food and agriculture: Trends and challenges. Retrieved from http://www.fao.org/3/a-i6583e.pdf
Food and Agriculture Organization. (2023). AQUASTAT: Agriculture water use. Retrieved from http://www.fao.org/aquastat/en/data-analysis/irrigation-water-use/agricultural-water-withdrawals-by-region/
Gruère, G. P., & Shigemitsu, M. (2021). Food demand projections to 2050: Implications for agricultural water demand. Water Resources and Economics, 37, 100182.
Rahut, D. B., Aragie, E. M., Marenya, P. P., & Kassie, M. (2022). Assessing household water access, use, and management for agriculture and human consumption in rural Ethiopia. Journal of Environmental Management, 308, 114389.
Rosa, L., Boretti, A., & Guerrini, A. (2019). Water and food security: Analysis of intersectoral relations. Water, 11(8), 1633.
Sans, P., & Combris, P. (2015). World food security and food safety: A review of the literature. Public Health Reviews, 36(1), 1-29.
United Nations. (2022). The world's cities in 2022. Retrieved from https://population.un.org/wup/Publications/Files/WUP2022-Report.pdf
van Dijk, A. I., Wada, Y., & Tielens, E. T. (2021). The global hydrological cycle under future climate change. Nature, 596(7870), 379-385.
World Bank. (2019a). Agricultural water withdrawal (% of total freshwater withdrawal). Retrieved from https://data.worldbank.org/indicator/ER.H2O.IRRG.ZS
World Bank. (2019b). Water withdrawal and sanitation indicators. Retrieved from https://data.worldbank.org/topic/water