Role of Thermophilic Micro flora in Composting

Abstract

Composting is a process that converts organic waste to a humus-like end product and is not only a waste treatment technique but also a recycling method as the end product can be used in agriculture as fertiliser, in gardening or in landscaping. Microbes play a key role as degraders during the composting process; mesophilic microflora constitutes the pioneer component, while thermophilic microflora, the climax and also the dominant component contributes significantly to the quality of compost. The dynamics of microbial community in different compost ecosystems change in context with qualitative and quantitative changes in physico-chemical conditions of compost. Optimisation of compost quality is directly linked to composition and succession of microbial communities in compost ecosystem. This necessitates the monitoring and characterisation of the microbial community composition, patterns and dynamics of species diversity at spatial scales. The biasedness and time-consuming nature of cultivation-based approaches severely limits spatial and temporal intensity of sampling, but with the advent of culture-independent molecular techniques, new insights into the composition of uncultivable communities have been gained. It has also been now possible to define the causes of time-dependent changes in the health of microbial community on the basis of observed 16S and 18S rDNA diversity. The genomic information represented by such a "community genome" offers a tremendous resource for examining the extent and patterns of microbial genetic diversity and metabolic capabilities in the natural ecosystem. These studies also provide basic knowledge on mechanisms that control species coexistence, which have fundamental applications since they offer the framework that serves in maintaining, restoring and manipulating the diversity in natural compost ecosystem and hastening the process of composting besides improving the quality of compost.