Comparison of source-separated municipal solid waste compost and solid manure

Composting of source-separated municipal solid waste (SSMSW) is an option c urrently being used to divert refuse from landfills in Nova Scotia. Only ag ricultural lands can accept the volume of compost that will be produced. Th e purpose of this project was: 1) to compare the availability of nutrients from SSMSW compost and semi-solid beef manure, and 2) to determine the envi ronmental consequences of using SSMSW compost on agricultural lands. A field experiment was established where the main plots were semi-solid man ure (M) and SSMSW compost (C) applied at 0, 50, 100, and 150 kg of plant av ailable N (PAN) per hectare. PAN was assumed to be 15% and 50% of the total N of compost and manure, respectively. Compost, manure and fertilizer were also applied in 1997 to give similar PAN as applied in 1996. The rate of m anure addition was decreased since 15% of the total N in the manure applied in 1996 was assumed to be available in 1997. Compost was assumed to have n egligible residual N availability. Barley was seeded in 1996 and wheat was seeded in 1997 Cereal boot-stage N, K, and Mn concentrations were higher in plots amended with manure than those amended with compost in 1996 (barley) and 1997 (whea t). However, boot-stage Na, Mg and Cu concentrations, tended to be higher i n the compost-amended plots. As manure addition increased, the concentratio ns of N (barley and wheat), K (barley and wheat), Ca (wheat), Mn (barley), Cu (wheat), and Na (barley), increased. As the rate of compost addition inc reased, the concentration of Mg (barley and wheat) decreased, while that of Cu (barley) and Na (barley) increased. Although compost and manure additio ns both increased grain yields, manure-amended plots had a higher grain yie lds than plots amended with compost. When applied at similar rates of assumed plant-available N, soil organic ma tter content, pH, and Ca, Mg, Cu and Zn and B content was higher where comp ost rather than manure had been applied. Soil K content, however, was highe r where manure had been applied. The soil physical parameters, bulk density and resistance to penetration we re lower where compost rather than manure had been applied.