Total volume (TV) and volume increase (VI) expressed as cubic feet per linear foot of compost windrow of sawdust and yard waste compost during the in-house composting trial. Logarithmic regressions of sawdust compost volume on day of trial (TV = − 2.98 + 2.16 ln(day), R 2 = 0.98; VI = − 5.71 + 2.16 ln(day), R 2 

Contexts in source publication

Context 1

... If long-term composting with a large initial volume of carbon source is desired, and it is intended to use the process to control fly production, it would be important to amend the carbon source with sufficient nitrogen and moisture to promote activity of thermophilic microbes and heat the compost as quickly as possible. This amendment could be manure or in-house compost left behind from the previous clean-out. Total compost volume and volume accumulation of the sawdust compost rose relatively rapidly until about 84 d, after which the rate of volume increase was lower until the end of the study ( Figure 1). This trend in volume increase was a little less evident for the yard waste compost (Figure 1), wherein the logarithmic regression of volume growth over time had less pre- dictive value than was the case for sawdust compost (R 2 = 0.88 vs. 0.98, respectively). By the end of the study at 331 d, the volume (volume increase) of the sawdust compost was estimated to be 9.2 ft 3 /ft (6.5 ft 3 /ft) and that of the yard waste compost 10.2 ft 3 /ft (5.6 ft 3 /ft). The undisturbed manure in house 1 had an average volume exceeding 13 ft 3 /ft at the end of the study, so that despite the added carbon sources, the final volumes of the composts were 22 to 29% reduced by comparison. These volume reductions are somewhat less than the 34% relative volume reduction reported for in-house compost in a naturally ventilated, curtain-sided, high-rise house [1]. The higher rate of increase of compost volume at the beginning of the trial reflects a slow start to the composting process. A similar pattern of volume growth was noticed during an in-house composting study in a naturally ventilated, curtain-sided, high-rise house [1]. It is unlikely that starting windrow volume in itself played much of a role in the slow initiation of compost action because this was larger than needed to develop peak compost heating [4]. The slow startup of composting probably was due to the initially low supply of nutrients necessary for composting to occur. These nutrients evidently did not reach concentrations sufficient to support high activity of thermophilic microor- ganisms throughout the compost until weeks into the trial. Miner et al. [4] were able to achieve active in-house composting in less than 10 d after forming compost windrows in which the manure content was high enough to reduce the C/N ratio to less than 20. After d 47, when compost weight measurement began, bulk density increased similarly for both sawdust and yard waste compost in a linear fashion on a DM basis (Figure 2). The final bulk densities of the 2 compost types were close, being 29 lb of DM/ft 3 and 28 lb of DM/ft 3 for the sawdust and yard waste composts, respectively. In studies by Thompson et al. [1] and Webster et al. [9], final DM mass of ...

Context 2

... If long-term composting with a large initial volume of carbon source is desired, and it is intended to use the process to control fly production, it would be important to amend the carbon source with sufficient nitrogen and moisture to promote activity of thermophilic microbes and heat the compost as quickly as possible. This amendment could be manure or in-house compost left behind from the previous clean-out. Total compost volume and volume accumulation of the sawdust compost rose relatively rapidly until about 84 d, after which the rate of volume increase was lower until the end of the study ( Figure 1). This trend in volume increase was a little less evident for the yard waste compost (Figure 1), wherein the logarithmic regression of volume growth over time had less pre- dictive value than was the case for sawdust compost (R 2 = 0.88 vs. 0.98, respectively). By the end of the study at 331 d, the volume (volume increase) of the sawdust compost was estimated to be 9.2 ft 3 /ft (6.5 ft 3 /ft) and that of the yard waste compost 10.2 ft 3 /ft (5.6 ft 3 /ft). The undisturbed manure in house 1 had an average volume exceeding 13 ft 3 /ft at the end of the study, so that despite the added carbon sources, the final volumes of the composts were 22 to 29% reduced by comparison. These volume reductions are somewhat less than the 34% relative volume reduction reported for in-house compost in a naturally ventilated, curtain-sided, high-rise house [1]. The higher rate of increase of compost volume at the beginning of the trial reflects a slow start to the composting process. A similar pattern of volume growth was noticed during an in-house composting study in a naturally ventilated, curtain-sided, high-rise house [1]. It is unlikely that starting windrow volume in itself played much of a role in the slow initiation of compost action because this was larger than needed to develop peak compost heating [4]. The slow startup of composting probably was due to the initially low supply of nutrients necessary for composting to occur. These nutrients evidently did not reach concentrations sufficient to support high activity of thermophilic microor- ganisms throughout the compost until weeks into the trial. Miner et al. [4] were able to achieve active in-house composting in less than 10 d after forming compost windrows in which the manure content was high enough to reduce the C/N ratio to less than 20. After d 47, when compost weight measurement began, bulk density increased similarly for both sawdust and yard waste compost in a linear fashion on a DM basis (Figure 2). The final bulk densities of the 2 compost types were close, being 29 lb of DM/ft 3 and 28 lb of DM/ft 3 for the sawdust and yard waste composts, respectively. In studies by Thompson et al. [1] and Webster et al. [9], final DM mass of ...