Physicochemical Characteristics of Animal and Municipal Wastes Decomposed in Arid Soils

Abstract

The application of anaerobically processed animal manure to maintain adequate levels of organic matter in arid soils is becoming a common practice. The purpose of this study was to characterize two farm manure products as compared with municipal waste compost (MWC). The anaerobic processing to obtain a biogas manure (BM) product was much faster (25 d) than the aerobic composting of farmyard manure (FYM) (90 d). Drying by three different methods (solar-drying, vacuum-drying at 45 degrees C, and freeze-drying) did not affect the quality of BM. Based on the chemical characteristics, FYM and BM products were comparable, and, containing less ash (30%) and heavy metals (50 mg Pb kg(-1)), seemed superior to MWC that contained 65% ash and 108 mg Pb kg(-1). On the other hand, MWC had higher C content (69.9%), lower acidity (15.04 mol kg(-1)), and higher exothermic peaks (300-460 degrees C) than BM and FYM (50% C, 20 mol kg(-1), and 275-450 degrees C, respectively), thus showing a greater extent of humification. Also, when the organic materials were incubated with arid soils and monitored for mean residence times (MRT), MWC was slightly more resistant to decomposition (MRT 175-180 d) than BM or FYM (MRT 161-166 d). The observed differences, however, were too small to dismiss any of the products as a valuable material for land applications to improve soil quality. In view of the results obtained, MWC may be considered an adequate substitute for BM or FYM, whenever the latter are in short supply.

Drying Poultry Manure for Pollution Potential Reduction and Production of Organic Fertilizer

“…Poultry manure begins to decompose immediately after excretion giving off ammonia which, in high concentrations, can have adverse effects on the health and productivity of birds as well as the health of the farm workers (Pierson et al, 2001;Zhang and Lau, 2007;Amon et al, 2006). Manure is a source of odor caused by the activity of microorganisms in the manure and can also serve as a breeding ground for pathogenic microorganisms as well as a transmitting medium for diseases among the birds (Berry and Miller, 2005;Fares et al, 2005). Flies and other…”

Drying of Poultry Manure for Use as Animal Feed

“…Flies and other undesirable insects can breed on the manure leading to the health hazards and nuisances associated with them (Lay et al, 2011;Axtell, 1999). Manure is also a source of odor caused by the activity of anaerobic microorganisms in the manure (Berry and Miller, 2005;Fares et al, 2005). It is, therefore, necessary to subject poultry manure to some treatments in order to improve its storage and handling properties and to minimize the risk of disease transmission and environmental pollution.…”

Composting of Calotropis gigantea Leaves In Presence of Sheep Dung

“…Organic carbon is being utilized by microorganisms present in compost as energy source and its reduced amount reveals decomposition of waste by microbial action 20 . A portion of this carbon is assimilated by microbial cells and some part is lost as carbon dioxide [21][22][23][24] .…”