Associate Professor of Soil and Water Science
Institute of Food and Agricultural Sciences
“Harmonic development of agriculture with the environment” is the past five-year research goal for Zhenli He. Eutrophication of surface water such as Lake Okeechobee and Indian River Lagoon, and degradation of native ecosystems, like Everglades National Park, have become an increasing public concern in South Florida. Agriculture is suspected to be one of the major non-point pollution sources. Fertilizer applications and irrigation are used to achieve desired crop yield and optimal fruit quality on these soils, but any unused nutrients or chemicals are subjected to leaching and/or surface runoff losses.
Therefore, research is needed to develop scientifically sustainable agriculture practices while simultaneously protecting our environment. It is essential that we minimize the transport of nutrients, heavy metals, and pesticides from land to waters, using phytoremediation integrated with natural and man-made wetland to filter nutrients or contaminants in stormwater before it is discharged to surface water systems. He has worked closely with Federal and State agencies and industry to develop such technologies. The phosphorus slow release fertilizers he developed by combining dolomite phosphate rock, a waste from phosphate mining, with sewage sludge (biosolids) can meet phosphorus (P) requirements for crops while significantly reduce P loss in surface runoff.
He’s studies also demonstrate that Ca-water treatment residuals (Ca-WTR) are useful in acidic soils to reduce P loading in surface runoff while improving crop yield and quality. By using Ca-WTR, which is clean and safe, instead of limestone, growers can reduce production costs, simultaneously water plants, and minimize disposal costs.
He’s research has also developed new phytoremediation technologies for water detention systems and stormwater treatment areas. Results indicate that water lettuce can be useful in remediating eutrophic water in a confined environment, such as a detention system, as it can remove both nutrients (N, P) and contaminants such as heavy metals and pesticides.