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Phytoremediation is an environmentally friendly and effective method of reducing contaminating ions to very low levels. In this study, the effects of different concentrations of cadmium (Cd), copper (Cu), and lead (Pb) on vegetative growth and the chemical and biochemical compositions of Salix mucronata as well as the potential for phytoextraction of these metals by plant organs were investigated. S. mucronata had the highest survival percentage (100%) in the presence of CdCl₂, CuCl₂, and Pb acetate up to 80, 200, and 850 mg·kg⁻¹ in soil, respectively. A negative influence of these metals on vegetative and chemical parameters was observed relative to the control plants. The potential role of antioxidant enzymes in protecting plants from oxidative injury was examined by analyzing the antioxidant enzyme activities of plants grown in contaminated and control soils. Enzymatic activities and electrolyte leakage were higher in the plants grown in soil with increasing heavy metals than in the control plants. The bioconcentrating efficiency of Cd, Cu, and Pb in plant organs was estimated to be medium [bioconcentration factor (BCF) of 1–0.1]; an exception was the BCF of Cu in the roots, which was estimated to be intensive (BCF < 1). Concentrations of 60 mg·kg⁻¹ CdCl₂, 50 mg·kg⁻¹ CuCl₂, and 650 mg·kg⁻¹ Pb acetate caused significantly higher translocation compared with other levels of each pollutant. The biomass tolerance index was less than 1. Additionally, S. mucronata accumulated Cd, Cu, and Pb in the following order: roots > stems > leaves. Therefore, the risk of contamination through leaf fall can be minimized. Therefore, S. mucronata could be a good candidate for phytoremediation of Cd-, Cu-, and Pb-contaminated soil.

Urea cocrystal materials are a potential fertilizer source that has shown to decrease environmental nitrogen losses. Novel nitrogen (N)-containing urea cocrystal fertilizers, CaSO₄·4urea (UC1) and Ca(H₂PO₄)₂·4urea (UC2), were synthesized using the mechanochemical method to form stable urea cocrystals to be tested as a fertilizer source for turfgrass. The objectives of this study were to 1) evaluate the response of ‘Tifway’ hybrid bermudagrass (Cynodon dactylon × C. traansvalensis Burt Davy) to N fertilization by urea cocrystals and traditional coated urea products (MU·PCU, methylene urea, urea, polymer-coated urea; PCU, polymer-coated urea, urea) supplied at two rates at the beginning of two, 10-week study periods conducted under a greenhouse setting and 2) investigate N release behavior of urea and two cocrystal products using a rapid water release test. In the turfgrass response study conducted in the greenhouse, improved turfgrass quality above the minimum quality threshold was observed when averaging across all products. For normalized difference vegetation index (NDVI), cocrystal outperformed all other products in the summer study and both cocrystal products outperformed the traditional product (MU·PCU) in the winter study. Further, both cocrystal products showed favorable growth responses compared with the commercial products provided by positive clipping production and vertical extension rates. In the nitrogen release experiment, a rapid water release test revealed the N release peak of urea was significantly higher than both UC1 and UC2. Furthermore, significantly higher N was leached from urea (15% loss) compared with both UC1 and UC2 (≈8% loss). Results from both studies provide evidence supporting suitability of urea cocrystal application on bermudagrass and potential as a slow-release fertilizer source through sustained turfgrass vigor, growth, decreased N release peak, and decreased leaching losses.