Decomposition of organic matter is an important ecosystem process governed in part by 33 bacteria. The process of decomposition is expected to benefit from interspecific bacterial 34 interactions... Show moreDecomposition of organic matter is an important ecosystem process governed in part by 33 bacteria. The process of decomposition is expected to benefit from interspecific bacterial 34 interactions such as resource partitioning and facilitation. However, the relative 35 importance of resource niche breadth (metabolic diversity) and resource niche overlap 36 (functional redundancy) on decomposition and the temporal stability of ecosystem 37 processes received little scientific attention. Therefore, this study aims to evaluate the 38 effect of an increase in bacterial community resemblance on both decomposition and the 39 stability of bacterial metabolism in aquatic sediments. To this end, we performed 40 laboratory microcosm experiments in which we examined the influence of bacterial 41 consortia differing in number and composition of species on bacterial activity (Electron 42 Transport System Activity, ETSA), dissolved organic carbon production and wavelet 43 transformed measurements of redox potential (Eh). Single substrate affinities of the 44 individual bacterial species in order to calculate the metabolic diversity of the microbial 45 community. Results presented here indicate that bacterial activity and organic matter 46 decomposition increase with widening of the resource niche breadth, and that metabolic 47 stability increases with increasing overlap in bacterial resource niches, hinting that 48 resource niche overlap can promote the stability of bacterial community metabolism. Show less
