Saving Water from Field to Fork: Sustainable Agriculture Through Conservation
Water scarcity poses a significant challenge globally. With excessive water usage and increasing demands from various sectors, freshwater availability for human consumption and agricultural purposes is dwindling. This severely threatens food security and economic stability in numerous regions.
The agriculture industry has a crucial role in promoting sustainability amidst growing environmental concerns. One area where agriculture can have a significant impact is water conservation. With the world’s population increasing and climate change threatening water availability, it becomes essential for the agricultural sector to adopt efficient water management practices. By implementing water conservation methods, the industry can contribute to preserving this precious resource, ensuring long-term sustainability, and reducing the effects of water scarcity. This article explores the significance of water conservation in agriculture, provides insightful examples, and highlights the benefits of adopting these practices.
The Urgent Need for Water Conservation
Agriculture is the biggest consumer of the world’s freshwater resources, accounting for approximately 70% of global water withdrawals. As the global population expands exponentially, water demand for agriculture will only intensify. This makes adopting sustainable water management in the agricultural sector critical to maintaining productivity and, more importantly, conserving this precious shared resource.
The overexploitation of surface and groundwater for irrigation is already creating a severe strain on water supplies in many parts of the world. Aquifer and well depletion, the drying up of lakes and rivers, and the salinization of soils from intensive irrigation are significant problems we face today. Climate change is also altering precipitation and evapotranspiration patterns, causing extreme weather events like droughts and floods that threaten rain-fed agriculture. We need urgent efforts to optimize water usage to avoid endangering world food security.
The good news is that sustainable water management in agriculture is achievable through various techniques and technologies. The incentive for farmers to adopt these methods is also greater today, with water conservation increasingly tied to farm subsidies, insurance rates, and pricing in water-stressed regions.
Water Conservation Methods in Agriculture
Drip and sprinkler irrigation methods deliver water and nutrients directly to plant roots, reducing agricultural water usage by 30%-60% compared to conventional flood irrigation while still maintaining high crop growth. This method has been successfully implemented in various crops, including fruits, vegetables, and row crops, leading to significant water savings without compromising crop yields. As per a recent study, converting just 50% of flood-irrigated land worldwide can save enough water to supply the whole of Africa’s domestic needs. Israel’s drip irrigation revolution transformed its agriculture sector in arid environments. India, China, and other developing nations are also pushing towards using sprinklers and micro-irrigation with government subsidies.
Precision farming, or precision agriculture, utilizes advanced technologies such as GPS, sensors, and data analytics to optimize agricultural practices. Moisture sensors coupled with automatic valves in drip systems restrict irrigation to requirements. NASA’s satellite imaging can map soil moisture levels across landscapes to help optimize water applications. By collecting real-time data on soil moisture, weather conditions, and crop needs, farmers can precisely determine when and how much water to apply. This approach allows for targeted irrigation, reducing water waste, and ensuring optimal crop growth.
Simple gravity flow techniques like guzzlers, contour bunds, and field bunding to capture rain runoff have been successfully used for centuries in Africa, the Middle East, and Asia. Traditional water harvesting structures like johads, khadins, and village tanks in India collect monsoon rains for subsequent irrigation and groundwater recharge. Laser land leveling, which measures fields and slopes them precisely to avoid water pooling or runoff, can improve field-level irrigation efficiency by up to 15–30%.
Alternate wetting and drying techniques for rice cultivation cut water demands by 30% with no yield reductions. Keeping fields intermittently flooded rather than continuously flooded reduces percolation losses while preserving crop yield. Crop diversification from water-intensive crops to pulses, horticulture, and agroforestry also optimizes agricultural water productivity.
Improved soil management is another crucial water conservation strategy — techniques like no-till farming, cover cropping, and controlled grazing help soils better retain moisture. A study revealed that implementing cover crops could lead to a 50% reduction in water runoff compared to using bare soils.
Because of the water and energy savings they generate for farmers, these measures frequently have a short payback period; however, individual small and marginal farmers may need more access to capital, technical knowledge, and economies of scale. For example, installing more efficient irrigation systems or implementing no-till farming requires some upfront investment, but these practices can reduce water usage and pumping costs over the long-term. California farmers can save $1 billion annually by reducing agricultural water use by 25%, but governments and external agencies need to provide planning, infrastructure, subsidies, and service expansion to promote sustainable water management.
Corporate agribusiness players also have a significant role to play. Major beverage companies like Anheuser-Busch InBev and Coca-Cola are working with GAIN, WWF, and other NGOs to sustainably manage watersheds shared by their facilities and smallholder farmers in critical regions like Africa, Brazil, and India. Unilever is training thousands of tea farmers in precision water management in order to secure supplies for its global tea brands.
Overall, water conservation enables a more resilient, sustainable agricultural system. Everyone must come to the table and play their part to truly mainstream water stewardship in agriculture. Farmers need access to technology and training; regulators must direct policy; agribusiness must assist their contracted growers; and consumers should support sustainable products. The time has come for all stakeholders to join hands to usher in a Blue Revolution in agriculture for our collective water security.
Recommended Readings
Cooley, H., Donnelly, K., Soqo, S., & Bailey, C. (2015). Drought and agriculture in California. Oakland, CA: Pacific Institute.
Food and Agriculture Organisation. (2022). Water management in agriculture. United Nations FAO. https://www.fao.org/3/i7959e/i7959e.pdf
Grafton, R., Williams, J., Perry, C., Molle, F., Ringler, C., Steduto, P., Udall, B., Wheeler, S., Wang, Y., Garrick, D. & Allen, R. (2018). The paradox of irrigation efficiency. Science, 361(6404), 748–750.
Jägermeyr, J., Pastor, A., Biemans, H. & Gerten, D. (2017). Reconciling irrigated food production with environmental flows for Sustainable Development Goals implementation. Nature communications, 8(1), 1–9.
Prathapar, S., Jamrah, A., Ahmed, M., Al Adawi, S., Al Sidairi, S. & Al Harassi, A. (2006). Overcoming constraints in treated greywater reuse in Oman. Desalination, 186(1–3), 177–186.
Rockström, J. & Falkenmark, M. (2015). Agriculture: Increase water harvesting in Africa. Nature, 519(7543), 283–285.
Smith, J. (2021). Advances in precision irrigation systems. Irrigation Science, 39(6), 523–540.
Wang, G., Ngouajio, M., & Warncke, D. (2019). Nutrient loss and water quality under cover crop in field plots. Journal of Environmental Quality, 48(2), 318–324.