Despite having a distinctive isotopic signature, S derived from ammonium sulfate fertilizer is difficult to detect in soil profiles or runoff because other sources of S are relatively large and vary in S concentration and S isotope composition. Concentrations of dissolved sulfate in S5 runoff are elevated compared to runoff from unimproved pasture W4, primarily because drainage improvements and land use practices at S5 increase the leaching efficiency of sulfate.

Organic-bearing soils at the study site efficiently retain historically added U, and by inference, also retain at least some added P. Efforts to limit P in runoff from similar soils in central Florida are well served by management techniques that preserve soil organic matter and that minimize transport of suspended (colloidal or particulate) organic matter in runoff.