Impact of Composting Methods on Nitrogen Retention and Losses during Dairy Manure Composting

• Published in: International journal of environmental research and public health 2019-09, Vol.16 (18), p.3324
• Main Authors: Yang, Xiao, Liu, Enke, Zhu, Xinmeng, Wang, Hongyuan, Liu, Hongbin, Liu, Xiu, Dong, Wenyi
• Format: Article
• Language: English
• Subjects: Ammonia - analysis; Animal manures; Animal wastes; China; Composting; Composting - methods; Composts; Dairy wastes; Dairying; Environmental conditions; Fertilizers; Gases; Groundwater; Groundwater pollution; Leachates; Leaching; Livestock; Manure - analysis; Manures; Methods; Moisture content; Nitrogen; Nitrogen - analysis; Nitrous Oxide - analysis; Pathogens; Pollutants; Reactors; Sediment pollution; Sensors; Soil pollution; Soil water; Studies; Surface water; Surface-groundwater relations; Water pollution
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph16183324

Currently, composting is one of the most effective methods for treating fecal waste on large-scale livestock and poultry farms, but the quality effects of different composting methods are different. In this study, we implemented four composting methods, including farmer compost (FC), anaerobic compost (AnC), mixed compost (MC), and aerobic compost (AC), to study the effects of different composting methods on nitrogen (N) losses while composting dairy manure. Our results showed that the germination indexes (GIs) of three of the composting treatments (AnC, MC, and AC) exceeded 80%, which met the maturity requirements for composted products. Ammonia (NH ) emissions were the main contributor to nitrogen losses, while accumulated nitrous oxide (N O) emissions accounted for the lowest proportion of nitrogen losses. The cumulative N losses via the leachate of the AC treatment were the lowest and accounted for 0.38% of the initial total nitrogen (TN). The accumulated N losses of the AC, FC, AnC, and MC treatments accounted for 13.13% 15.98%, 15.08%, and 19.75%, respectively, of the initial TN. Overall, the AC method significantly reduced N losses via leachates, further reducing TN losses. This observation suggests that AC might be an appropriate method for highly efficient nitrogen management during dairy manure composting.