Composition variability of spent mushroom compost in Ireland

Abstract

Spent mushroom compost (SMC) has proven to be an attractive material for improving soil structure in tilled soils and increasing dry matter production in grassland soils, owing to its high organic matter content and availability of essential plant nutrients. Because of this, it is important to identify the variability in composition of SMC in order to evaluate its merit as a fertilizer/soil conditioner. For this reason, a study was carried out involving the analysis of SMC samples obtained from five mushroom growers using compost from each of the 13 mushroom composting yards currently operating in both Northern Ireland (5 yd) and the Republic of Ireland (8 yd). The selected parameters measured include dry matter, organic matter, total N, P and K, C/N ratio; plant-available P and K, pH, EC, total Ca, Mg, Na, Cu, Zn, Fe, Mn, Cd, Cr, Ni, Pb; and cellulose, hemicellulose and lignin constituents. Yield of mushroom data were also collected from the selected growers. There were significant differences (P<0.05) within two compost production yards for some parameters, therefore, for the most part, the uniformity of SMC within each yard is relatively consistent. However, significant differences (P<0.05) were evident when comparing SMC obtained from growers supplied with compost from Northern Ireland and the Republic of Ireland independently, particularly among total and available phosphorus and potassium values. The results obtained show that, while SMC has fertilizer merit, its variability of composition must be taken into account when assessing this value. The variability of composition is also of particular interest in the context of recent emphasis on plant nutrient management in agriculture.

Spent Mushroom Substrate as a Transplant Media Replacement for Commercial Peat in Tomato Seedling Production

“…This feature is mostly responsible for limiting the use of SMS as a potting substrate, soil amendment and fertilizer source. Similar to Jordan et al (2008) the high salinity is related to high levels of available K. Medina et al (2009) also related high EC of SMS based media to increase ion concentrations, which they inferred was the result of addition of manures, CaSO 4 etc. during compost preparation for mushrooms.…”

“…However, only the PM media showed EC values comparative to an ideal substrate. The SMS media was highly saline (Maher et al, 2000, Jordan et al, 2008. This feature is mostly responsible for limiting the use of SMS as a potting substrate, soil amendment and fertilizer source.…”

Humusica 2, article 16: Techno humus systems and recycling of waste

“…It is used for the culture of Agaricus bisporus and 5 kg of mushroom substrate are needed to obtain 1 kg of mushroom (Williams et al, 2001;Rasib et al, 2015). The farming amendment, at the end of the mushroom cultivation cycle, is an organic substrate rich in nutrients (Jordan et al, 2008), especially nitrogen, which has a considerable agronomic value when used as a fertilizer or soil improver (Curtin and Mullen, 2007;Medina et al, 2009;Zhang et al, 2012).…”

The role that lignocellulosic feedstocks and various biorefining technologies can play in meeting Ireland's biofuel targets

“…Unfortunately, reliable lignocellulosic compositional data for Irish SMC are lacking and variations in conditions and substrate-feedstocks between countries (for example, most mushroom facilities in The Netherlands use horse manure rather than poultry litter [109]) make the use of foreign data inappropriate. The data that do exist in Ireland and Northern Ireland [72,110] utilise gravimetric methods [111] for approximating cellulose, hemicellulose and lignin but such methods may be very inaccurate in such a heterogeneous feedstock that will contain a lot of carbohydrate degradation products and lignoproteins.…”

“…The total carbohydrate (57%) [112] assumed in this study for this feedstock is attractive for such a low cost feedstock. Further consideration of the particular chemistry of the material suggests that the polysaccharides could be particularly attractive substrates for hydrolysis given that the production of SMC can be considered to represent a form of pre-treatment.…”