Soil Properties as Influenced by Phosphorus‐ and Nitrogen‐Based Manure and Compost Applications

TLDR

Manure or compost applied to meet corn nitrogen needs can cause soil accumulation of phosphorus, nitrogen, and other ions because the manure N/P ratio is typically lower than the crop’s uptake ratio. The study evaluated the effects of annual or biennial application of N‑ and P‑based composted and non‑composted beef cattle manure on soil properties. The experiment included fertilized and unfertilized control plots to compare against the manure and compost treatments. After four years, N‑based manure and compost raised surface soil pH, increased carbon and nitrogen concentrations relative to P‑based treatments, and sequestered more carbon (25 % of manure C and 36 % of compost C remained), while bulk density, total C and N, and deeper‑soil properties were largely unchanged except for higher residual nitrate under inorganic fertilizer and greater electrical conductivity changes.

Abstract

Manure or compost application based on N needs of corn ( Zea mays L.) may result in soil accumulation of P, N, and other ions, since the manure or compost N/P ratio is usually smaller than the corn N/P uptake ratio. This study was conducted from 1992 to 1996 to evaluate the effects of annual or biennial application of N‐ and P‐based composted and noncomposted beef cattle ( Bos taurus ) feedlot manure on soil properties. Fertilized and unfertilized checks were also included. Soil surface (0–15 cm) pH significantly increased with N‐based manure (MN) or compost application (CN), but decreased with NH 4 –N fertilizer application as compared with the check. Soil bulk density was unaffected by manure or compost application. After 4 yr of manure and compost applications, soil surface (0–15 cm) C and N concentrations and quantities were greater for N‐ than P‐based management systems. About 25% of applied manure C and 36% of applied compost C remained in the soil after 4 yr of application, indicating greater C sequestration with composted than noncomposted manure. No significant difference was observed between fertilizer and check plots for soil total C or N. Soil properties in the 15‐ to 30‐cm increment were unaffected by the applied treatments except soil electrical conductivity (EC). Residual soil NO 3 to a depth of 1.2 m was greater for inorganic fertilizer than manure and compost treatments in drier years. Soil property changes were greater for the annual or biennial N‐based than P‐based manure or compost applications, reflecting the differences in application amounts.