Microbial Anaerobic Digestion (Bio-Digesters) as an Approach to the Decontamination of Animal Wastes in Pollution Control and the Generation of Renewable Energy

Abstract

Compost production is a critical component of organic waste handling, and compost applications to soil are increasingly important to crop production. However, we know surprisingly little about the microbial communities involved in the composting process and the factors shaping compost microbial dynamics. Here, we used high-throughput sequencing approaches to assess the diversity and composition of both bacterial and fungal communities in compost produced at a commercial-scale. Bacterial and fungal communities responded to both compost recipe and composting method. Specifically, bacterial communities in manure and hay recipes contained greater relative abundances of Firmicutes than hardwood recipes with hay recipes containing relatively more Actinobacteria and Gemmatimonadetes. In contrast, hardwood recipes contained a large relative abundance of Acidobacteria and Chloroflexi. Fungal communities of compost from a mixture of dairy manure and silage-based bedding were distinguished by a greater relative abundance of Pezizomycetes and Microascales. Hay recipes uniquely contained abundant Epicoccum, Thermomyces, Eurotium, Arthrobotrys, and Myriococcum. Hardwood recipes contained relatively abundant Sordariomycetes. Holding recipe constant, there were significantly different bacterial and fungal communities when the composting process was managed by windrow, aerated static pile, or vermicompost. Temporal dynamics of the composting process followed known patterns of degradative succession in herbivore manure. The initial community was dominated by Phycomycetes, followed by Ascomycota and finally Basidiomycota. Zygomycota were associated more with manure-silage and hay than hardwood composts. Most commercial composters focus on the thermophilic phase as an economic means to insure sanitation of compost from pathogens. However, the community succeeding the thermophilic phase begs further investigation to determine how the microbial dynamics observed here can be best managed to generate compost with the desired properties.

Bacterial community changes during composting of municipal crop waste using low technology methods as revealed by 16S rRNA

“…Temperatures are usually high in the tropics, which increases evaporation of moisture from compost when it is not covered. Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria and Planctomycetes which were the dominant phyla have been reported in other composting studies (Takaku et al, 2006;Danon et al, 2008;Székely et al, 2008;Vivas et al, 2009;Neher et al 2013;Karadag et al, 2013;Song et al, 2014;Manyl-loh et al. 2016).…”

“…Bacillus, Streptomycetes and Pseudomonas in addition to faecal coliforms, Seratia and Proteus were the dominant microbial community isolates from pit method composted urban organic wastes (Taiwo and Oso, 2004). Other studies to establish bacteria community during composting process used kitchen waste, sewage sludge and source-separated municipal solid or household wastes mainly in temperate climate (Kowalchuk et al, 1999;Peters et al, 2000;Ryckeboer et al, 2003;Connon et al, 2005;Neher et al, 2013;Song et al, 2014). Some studies have concentrated on microbial succession within one phase of the compost process.…”

Biogeographic patterns in below-ground diversity in New York City's Central Park are similar to those observed globally

“…Candidatus, Nitrososphaera, Sphingobacterium sp. and Rhodospirillaceae) that are probably associated with the compost added to the Park's soils [47]. Of the most abundant eukaryotic phylotypes from the two sample sets 73% of the 2342 phylotypes were shared between Central Park and the global soils, 9% were found only in Central Park and rspb.royalsocietypublishing.org Proc.…”

Responses of Soil Fungi to Logging and Oil Palm Agriculture in Southeast Asian Tropical Forests

“…The most abundant identified order of these shared OTUs, the Mortierellales, is globally ubiquitous, and has been found in diverse environments such as in snow mats [77], compost [78], and urban soils [52]. They have also been documented as both saprotrophs and endophytes [79,80], demonstrating their metabolic flexibility.…”