Greenhouse gas emissions during co-composting of cattle mortalities with manure |
| |
Authors: | Shanwei Xu Xiying Hao Kim Stanford Tim McAllister Francis J Larney Jingguo Wang |
| |
Affiliation: | (1) Agriculture and Agri-Food Canada Lethbridge Research Centre, 5403 1st Ave S., Lethbridge, AB, Canada, T1J 4B1;(2) Alberta Agriculture, Food and Rural Development, 5401 1st Ave S., Lethbridge, AB, Canada, T1J 4C7;(3) College of Resource and Environment, China Agricultural University, Beijing, 100094, People’s Republic of China |
| |
Abstract: | Following outbreaks of bovine spongiform encephalopathy (BSE), fewer cattle mortalities are being rendered. Composting may
be a viable on-farm alternative for disposal of cattle carcasses. A study was conducted to assess feasibility and greenhouse
gas (GHG) emissions during co-composting of cattle mortalities and manure. Using a tractor-mounted front-end loader, windrows
were constructed containing manure + straw (control; CK) or manure + straw + cattle mortalities (cattle mortality; CM). The
composting process lasted 310 d. The windrows were turned twice, at days 93 and 211, using either a tractor-mounted front-end
loader or a specialized shredder bucket. Maximum windrow temperatures were >50 °C for 36 out of 92 d (before first turning)
and 142 out of 208 d (after first turning) for the CM treatment and cattle mortalities were completely decomposed except for
a few large bones. The cumulative CO2 and CH4 emissions were significantly affected by the mortality treatment, but not by the turning technology or their interactions.
Significantly higher CO2 (53.6 g d−1 m−2) and CH4 (2.204 g d−1m−2) emissions were observed during the co-composting of cattle mortalities than manure composted with straw (23.0 and 0.742 g
d−1m−2 for CO2 and CH4, respectively). Similarly, N2O emissions were higher with mortalities than without and, for the CM treatment only, higher with shredder bucket than front-end
loader turning. In the final compost, CM had higher TN and NH4+-N contents than CK while TC and the C/N ratio were higher with compost turned with the front-end loader than with the shredder
bucket. In conclusion, composting was an effective means of disposing of cattle mortalities, but did increase GHG emissions
and the N content in the final compost. It is not known if GHG emissions are different than those that would be released from
natural decomposition of carcasses. The higher N content in compost containing mortalities would increase its agronomic value. |
| |
Keywords: | Greenhouse gas emissions Cattle mortality Compost windrow technology Beef feedlot manure Compost quality |
本文献已被 SpringerLink 等数据库收录! |
|