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Aerobic composting is a sustainable method for chicken manure recycling, while its unsuitable porosity and carbon to nitrogen ratio (C/N) may result in high nitrogen loss and incomplete composting. With the aim to investigate the effects of carbon-based additives and two ventilation rates on chicken manure composting and microbial community, two series of treatments were set up for chicken manure composting, in order to investigate their effects on the biodegradation process, ammonia (NH 3) emission, nitrogen loss, physiochemical properties and microbial community. The results showed that additives and ventilation rates set in the current study influenced the carbon dioxide (CO 2) production from the 2 nd week and also the physiochemical parameters during the entire process, while no inhibitory effect on the maturity were observed. With woody peat as additive, the NH 3 emission amount and nitrogen loss rate were shown as 15.86 mg and 4.02%, less than those in other treatments, 31.08-80.13 mg and 24.26-34.24%, respectively. The high aeration rate increased the NH 3 emission and nitrogen loss, which were varied when the additives were different. The terminal restriction fragment length polymorphism (T-RFLP) results showed that the additives and the ventilation rates changed the microbial community, while the prominent microbial clones belonged to the class of Bacilli and Clostridia (in the phylum of Firmicutes), and Alphaproteobacteria, Deltaproteobacteria and Gammaproteobacteria (in the phylum of Proteobacteria). Bacillus spp. was observed to be the most dominant bacteria in all the composting stages and treatments. It was concluded that woody peat could improve chicken manure composting more than other additives, especially on reducing nitrogen loss, meanwhile 0.18 L�min-1 �kg-1 DM was suitable for various additives. Therefore, suitable additive and aeration rate could be used in practical application, which could significantly reduce nitrogen loss without influence on the compos maturity process.

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Vegetable waste was aerobically composed using a trough-type system, and the resulting emitted volatile organic compounds were investigated. In addition, the succession pattern of microorganisms was analyzed. Aerobic fermentation was conducted using a tomato stalk-cow dung mix (a water content of 65% and a carbon-to-nitrogen ratio of 25:1). The emitted volatile organic compounds comprised of 58 kinds of compounds, including 2 sulfur-containing compounds, 3 alcohols, 3 esters, 3 aldehydes, 3 ketones, 6 halogenated hydrocarbons, 18 aromatic hydrocarbons, 17 alkanes, and 3 alkenes. The primary volatile organic compounds produced were methyl sulfide, ethyl acetate, ethanol, and acetaldehyde. Clustering and principal coordinate analysis suggested that the community succession changed throughout the composting process in the odor-producing habitat. High-throughput sequencing revealed that the bacterial community was comprised of Firmicutes, Chloroflexi, Proteobacteria, and Actinobacteria, whereas the dominant flora included Ascomycota, Basidiomycota, and Mucoromycota. These findings could aid in the mitigation of volatile organic compounds and odors during vegetable waste composting as well as contribute to the development of deodorizing bacteria.