Biosolids from Treated Swine Manure and Papermill Residues Affect Corn Fertilizer Value

Abstract

Biosolids derived from treatment of animal manure or industrial effluents can be used on farms, but their fertilizer value must be assessed. A 3‐yr field study was conducted on a clay soil in Quebec, Canada, to evaluate the effect of several biosolids on silage corn dry matter (DM) yield; N‐use efficiency; and soil N, P, Cu, and Zn availability. Raw liquid swine (Sus scrofa) manure (LSM), biosolids from four swine manure treatments (aerobic digestion [AER], anaerobic digestion [DIG], filtration [FIL], anaerobic digestion followed by chemical flocculation [DIG+FLO]), combined papermill biosolids (CPB), de‐inking paper biosolids (DPB), and mineral N fertilizer (MIN) were applied before corn planting at a targeted rate of 150 kg total N ha−1. The DIG and DIG+FLO biosolids resulted in silage corn DM yield, N accumulation, and early season soil N availability comparable to LSM with an N‐use efficiency about 70% of that for MIN. The AER biosolid resulted in low DM yield with an N‐use efficiency only 10% of that for MIN; FIL and CPB had an N‐use efficiency almost 40% of that for MIN, whereas DPB caused a decline in DM yield compared to a no‐N control. The LSM‐derived biosolids increased availability of soil P (0.34 kg kg−1 excess P) and, to some extent, Cu and Zn. The CPB and DPB biosolids had little impact on soil P, but DPB markedly increased Zn availability. Manure‐derived biosolids and CPB were satisfactory N sources for silage corn while manure‐derived biosolids caused soil P enrichment when applied based on crop N requirement.