Biosolids generally contain high concentrations of macronutrients including N, P, S, Ca, and Mg embedded in the organic matter62 (Table 3). Biosolids also contain many micronutrients essential for plant growth in varying amounts, including Mn, Cu, Zn, and Mo,62 but K concentrations in biosolids are generally low63 and supplemental K fertilizer may be necessary to maintain productivity in soils receiving biosolids.64 Biosolids may contain 1%–11% N and 0.7%–7.5% P on a dry-weight basis, wh...
