Effects of four additives in pig manure composting on greenhouse gas emission reduction and bacterial community change

Abstract

Four different additives of Medical stone (MS), Zeolite (ZL), Bamboo biochar (BC), and Wood vinegar (WV) were investigated in pig manure composting. The four additives reduced the peak CH₄ emission from 54% to 74%, while reduced N₂O loss from 36% to 69%, compared with control (CK). WV and ZL showed better ability in N₂O loss reduction, yet MS with the efficient inhibition both on CH₄ and NH₃ emissions. The bacterial community analysis indicated that bacterial diversity in the maturity phase was higher than that in the thermophilic phase, especially with treatments of ZL, BC and WV. The selected factors of pH, temperature, TOC and DOC could influence the thermophilic phase, while EC and TKN related closely with maturity phase in pig manure composting.

Keywords: Additive; Bacterial diversity; Composting; Gaseous emission; Wood vinegar.