Recovering the lost nutrients from subsurface drainage systems towards agricultural sustainability

View the project final report

Commodities

• Agronomic: corn, radish (oilseed, daikon, forage)

Practices

• Crop Production: application rate management, drainage systems, fertilizers, nutrient cycling, nutrient management
• Education and Training: decision support system, extension, farmer to farmer, mentoring, on-farm/ranch research, technical assistance
• Energy: bioenergy and biofuels, byproduct utilization

Farmers today are under multiple attacks. Supply chain disruptions have pushed global fertilizer prices to unprecedented heights, making it harder for  farmers to make a profit. In the North Central Region, the widely adopted artificial agricultural drainage systems benefit crop growth, but also discharge excess nutrients into waterways, decreasing nutrients use efficiency and leading to eutrophication. In this context, the intensification of agricultural food production in the United States faces daunting challenges in achieving agricultural sustainability.

In response to achieving more circular and sustainable food production systems in North Central Region, our project is dedicated to recovering the lost nutrients from the agricultural drainage systems that can reduce reliance on nutrients imports, increase nutrient-use efficiency, and release environmental pressures. We consider that subsurface drainage systems can be redesigned and treated as nutrient recovery systems rather than the primary cause of nutrients loss from intensive agricultural systems. This requires a shift of traditional conservation practices from nutrient loss reduction to nutrients recovery.

To achieve this goal, this project aims to design next-generation agricultural drainage systems that combine novel end-of-tile nutrients removal-to-recovery (R2) systems. The specific objectives are to: 1) develop sustainable and low-cost adsorbents (agricultural and industrial wastes as feedstocks) that can be used to adsorb and recover nutrients from drainage water; 2) design fillable modules that can easily place the adsorbents and be installed at the existing end-of-tile drainage systems; 3) reuse the spent adsorbents from the modules into the agricultural field as slow- releasing fertilizer and soil amendment. This project examines the feasibility of addressing multiple dimensions of sustainability and exploring agroecosystems potential by keeping nutrients in the closed agricultural loop if lost nutrients can be recovered and reused. The outcome of this project will directly benefit farmers and ranchers through addressing the most pressing issues they encounter: surging fertilizer prices, nutrients loss from croplands, and nutrient-induced water pollution.

We plan to conduct a series of lab and field-scale experiments to evaluate each objective across the entire project in the Agricultural Engineering Research and Training Farm, IL. The graduate student (Hongxu Zhou) will lead the project and meet with the advising professor and farm managers at least once a month to monitor progress and the team will guide the project in a coordinated manner.

This project is designed to improve agricultural sustainability by closing the nutrients cycle in the agricultural systems. The learning outcomes are expected to deliver a strong message to farmers, ranchers, and all participants: increasing the use of recycled nutrients and protecting the natural environment are of vital importance to achieving sustainable agriculture. In this project, the traditional best management practices in reducing nutrients loads will be further improved via recovering the lost nutrients from agricultural tile-drainage systems. By doing so, farmers can realize that agricultural practices, even a small step forward, can make a huge contribution to the circular economy and sustainable development. This project will also increase the farmers' motivation and initiative in participating in the Nutrients Reduction Strategy program, as they can receive financial benefits from recovered nutrients without spending extra money on additional fertilizers. Throughout the project, we recognize that farmers are at the forefront of global efforts to protect and regenerate nature. The project requires a series of laboratory and localized field experiments in close collaboration with farmers. The action outcomes of this project are expected to change farmers’ agricultural practices in a more sustainable production manner. That is, farmers will enable to apply the end-of-tile nutrients removal-to-recovery (R2) systems in their croplands and then learn how to reuse the recovered nutrients from the systems for crop growth.