The role of composting in recycling manure nutrients

Abstract

. 2006. The role of composting in recycling manure nutrients. Can. J. Soil Sci. 86: 597-611. Recently, composting has been gaining increased attention as an alternative means of handling manure generated by the livestock industry. Composting is not a new technology, it merely controls what is a natural decomposition process. A major advantage of composting is reduced mass, volume and water content compared with fresh manure which in turn reduces transportation requirements. Concomitant benefits include elimination of pathogens, parasites, weed seeds and odour emissions on land application. However, carbon (C) and nitrogen (N) losses and greenhouse gas (GHG) emissions are associated with composting. Nutrients are stabilized during composting which slows their release once soil-applied. Compost also enhances soil physical and biological properties and has a disease suppression effect. Where the supply of manure currently exceeds land availability for application, or in some future scenario, if producers need to comply with stricter manure application rate regulations, composting may be an option to encourage nutrient export from high-loading watersheds to soils that may benefit from nutrient and organic matter inputs. Composting may be seen as a means of maximizing the potential for recycling manure nutrients by soils and crops while protecting surface and groundwater resources from manure-related contamination.Key words: Manure, compost, nutrients, cropping systems, soil quality Larney, F. J., Sullivan, D. M., Buckley, K. E. et Eghball, B. 2006. Rôle du compostage dans le recyclage des éléments nutritifs du fumier. Can. J. Soil Sci. 86: 597-611. Depuis peu, le compostage retient de plus en plus l'attention comme solution de rechange à la manutention du fumier venant de l'élevage. Le compostage n'est pas une nouvelle technologie. Cette technique ne fait que réguler le processus naturel de décomposition. Un de ses atouts majeurs est de réduire la masse, le volume et la teneur en eau du fumier frais, avec les économies que cela suppose au niveau du transport. Les avantages concomitants comprennent l'élim-ination des microorganismes pathogènes, des parasites, des semences de mauvaises herbes et des odeurs au moment de l'épandage sur les terres. Toutefois, on associe au compostage des pertes en carbone (C), en azote (N) et en gaz à effet de serre (GES). Le compostage stabilise les éléments nutritifs, ce qui en ralentit la libération après application au sol. Le compost rehausse également les propriétés physiques et biologiques du sol, et a tendance à combattre la maladie. Quand la quantité de fumier dépasse la superficie des terres sur lesquelles on pourrait l'étendre et que l'agriculteur doit composer avec des règlements plus sévères quant aux taux d'application, le compostage pourrait favoriser le transfert des éléments nutritifs des bassins hydrographiques surchargés vers les sols susceptibles de profiter d'un apport d'éléments nutritifs et de matière organique. On pourrait voir dans le compostage un moyen pour max...

Winter and growing season nitrogen mineralization from fall-applied composted or stockpiled solid dairy manure

“…Properties of the compost and manure applied each fall are shown in Table 2. Since dry matter (DM) contents are typically greater for compost than manure (Larney et al 2006;Lehrsch and Kincaid 2007), the identical DM between amendments in 2003 is somewhat surprising. The manure in 2003 may have been collected from an older or smaller stockpile, one that had lost more water to evaporation.…”

“…While the composting of dairy cattle manure reduces the material's weight and volume to ease handling, transport, and field application (Draycott and Christenson 2003;Larney et al 2006), the composting process also emits NH 3 and the greenhouse gases CO 2 , CH 4 , and N 2 O to the atmosphere (Larney et al 2006). Composting also requires inputs of energy, land, equipment, and labor, and decreases the organic sources' N availability by increasing the stability of the remaining organic compounds (Eghball 2000;Eghball et al 2002;Gutser et al 2005).…”

Windrow temperatures and chemical properties during active and passive aeration composting of beef cattle feedlot manure

“…None of the locations in the passive treatment exceeded 55°C. This is a concern since one of the main objectives of composting is to reduce or eliminate pathogens so that they are not spread to a wider environment on land application (Larney et al 2006b). However, reported that >99.9% of total coliforms and E. coli were eliminated in the first 7 d of an active aeration composting study when mean windrow temperatures were 33.5 to 41.5°C, substantially lower than the guideline value of 55°C.…”

“…Recently, there has been increased interest in manure composting as an alternative handling practice (Larney et al 2006b). Composting is a natural aerobic process that changes fresh organic materials, such as livestock manure, to more stable products similar to humus (Rynk 1992;DeLuca and DeLuca 1997).…”

Nutrient and trace element changes during manure composting at four southern Alberta feedlots

“…Several southern Alberta feedlots have embraced manure composting as an alternative to land spreading of fresh manure (Larney et al 2006b;Larney and Hao 2007). Composting decreases manure volume (Larney et al 2000), and eliminates pathogenic bacteria , human parasites (Van Herk et al 2004) and weed seed viability (Larney and Blackshaw 2003).…”