Zhenli He’s research addresses issues related to sustainable agriculture and surface water quality, including development of best management practices to enhance nutrient use efficiency while minimizing environmental impact, phytoremediation of eutrophic storm waters, remediation of heavy metal contaminated soils, and water quality and produce safety. He’s studies identified a number of soil amendments that have potential to hold nutrients in soil. Calcium-water treatment residues have been demonstrated in fields to effectively reduce nutrient and metal loads to surface runoff waters (SRW) and improve crop yield and quality. This finding not only provides potential solution to remediation of contaminated soils, but also benefits to the water industry by reducing disposal costs of the waste. Water quality throughout south Florida has been a major concern for many years. Phosphorus (P) is commonly considered the responsible element for algal blooms. However, He’s study discovered that it is nitrogen (N), not P, that has contributed to water quality degradation in some water bodies in South Florida. This finding will have significant implications in watershed management. Microbial contamination of surface water affects food safety and human health. He conducted a 3-year monitoring study in the St. Lucie watershed, determining that both bacteria concentration and occurrence of Salmonella in SRW were affected by rainfall, water temperature, and concentration of organic matter and nutrients in the water. His research findings have improved the understanding of hyperaccumulating mechanisms of heavy metals in plants and biogeochemical processes of soil/water contamination and remediation, and provided scientific data to support sustainable agriculture and food safety in Florida and elsewhere in the world.