One of agriculture’s biggest environmental challenges may have a surprisingly practical solution: changing the type of sprinkler used in the field. A new UF/IFAS-led study examines how to maintain crop productivity while dramatically reducing water use and Florida groundwater contamination. The paper focuses on strawberry production, but its implications extend far beyond the industry.

Josue St Fort, a postdoctoral associate in the UF/IFAS Department of Soil, Water, and Ecosystem Sciences (SWES), is the lead author. The work grew out of his doctoral dissertation research. St Fort and colleagues evaluated five irrigation systems used during strawberry transplant establishment in Florida. They compared the conventional high-volume impact sprinkler system with four micro-sprinkler alternatives.

Using the HYDRUS-1D water-flow simulation model, the researchers quantified:

• Water infiltration
• Deep percolation below the root zone
• Potential leaching of nutrients and agrochemicals
• Relative groundwater contamination risk
• Irrigation efficiency

The work is especially important because Florida strawberries are grown on extremely sandy soils with plastic mulch systems. This combination intensifies water movement and contamination risks.

Rethinking Irrigation

The researchers found that changing sprinkler design, without altering fertilizer programs or crop varieties, could dramatically reduce groundwater contamination risk. Among the systems evaluated, the Jain Mini Revolver micro-sprinkler stood out. Compared with the impact sprinklers strawberry growers commonly use, the Mini Revolver reduced infiltration and deep percolation by about 89%.

That finding matters because deep percolation allows nutrients and agrichemicals to move rapidly beyond the crop root zone and into groundwater. That includes nitrate nitrogen, phosphorus, fungicides and pesticides that can eventually reach aquifers serving as major drinking water sources.

“What surprised us most was the scale of the difference,” said St Fort. “We expected the micro-sprinklers to improve efficiency, but seeing nearly a 90% reduction in deep percolation showed just how powerful irrigation design can be as an environmental management tool.”

The researchers estimate that switching from conventional impact sprinklers to the Mini Revolver system could prevent about 5,570 cubic meters of deep percolation per hectare during transplant establishment alone. That translates to almost 600,000 U.S. gallons of water per acre prevented from leaching downward. It is nearly enough water to fill an Olympic-sized swimming pool.

Co-author Davie Kadyampakeni, SWES associate professor and St Fort’s postdoctoral advisor, said irrigation modernization can improve efficiency while helping protect Florida groundwater resources.

“This research shows that water conservation and crop performance do not have to be competing goals,” Kadyampakeni said. “With the right irrigation technology, growers can improve efficiency while also reducing environmental risk.”

Looking Beyond Strawberries

Beyond strawberries, the study may help researchers and growers improve irrigation management across many agricultural systems. It also highlights the growing importance of data-driven agricultural management.

Using the HYDRUS-1D simulation model, the team developed a validated framework to predict infiltration, drainage, runoff and leaching behavior under different irrigation systems. That modeling approach could eventually be adapted for other cropping systems, including citrus, vegetables, blueberries, nursery crops and ornamental production systems.

“Many agricultural systems around the world rely on plasticulture, overhead irrigation and production on sandy or highly permeable soils,” St Fort said. “The principles we demonstrated could apply to arid-zone irrigation systems and tropical agriculture.”

“These are the kinds of practical solutions sustainable agriculture research is designed to deliver,” Kadyampakeni added.

The research article, “Modeling of infiltration dynamics using HYDRUS-1D: Optimizing micro-sprinkler selection for reduced groundwater contamination risk in strawberry production in Florida, USA,” was recently published in Agricultural Water Management. Other co-authors of this paper include Department of Horticultural Sciences Associate Professor Carlene Chase, who served as St Fort’s PhD advisor, and Associate Professor Shinsuke Agehara, and Department of Agricultural and Biological Engineering Assistant Professor Vivek Sharma and Professor Michael Dukes.

Read the full research article at ScienceDirect.

Featured image by Josue St Fort, Ph.D.

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