Each diversity index is associated with the specific biases. The Shannon index takes into account consistency of species abundance in OTUs, while the RG7420 chemical structure Simpson’s index is sensitive to abundant OTUs [36]. Chao richness is based on singletons and doubletons [37], while ACE is based on the distribution of abundant (≥10) and rare (≤10) species. A higher bacterial diversity was observed in the

agricultural soil in comparison to the saline barren soils as revealed by Shannon and Simpson diversity indices and other non parametric indices (Table 2). This suggests that the autotrophic bacterial distribution is likely to respond to different environmental variables such as pH, salinity, organic carbon and nitrogen concentrations A-1210477 supplier etc. and the dominant populations are selected in response to changes in these variables. The soil carbon and sulphur content appears to be the major determinants

of microbial community structure and function in the soil samples. But it is XAV-939 cell line difficult to ascertain which particular environmental variables are driving the observed pattern of biological diversity as many of the soil and environmental characteristics are interrelated. Environmental stability is important to the development and maintenance of biodiversity [38]. Stable environments are thought to support a higher degree of organisation, more complex food webs, more niches, and ultimately more species [39]. Our data is in agreement with these assumptions

as barren coastal saline soil ecosystem does not remain stable because of tidal influx thus representing less diverse ecosystem as compared to more stable agroecosystem. LIBSHUFF analysis of cbbL and 16S rRNA clone libraries verified a large degree of variability in agricultural and saline soils in all pairs of reciprocal comparisons. The differential community structure and membership in agricultural soil as compared to the saline soils were in agreement with our expectations. A change in the community composition with increase in salinity was evident at the phylum level. Microorganisms adapt to the altered salinity or they are replaced Thalidomide by microorganisms adapted to the changed conditions [40]. The replacement mechanism appears to operate at the phylum level, as changes of major groups were observed with increased salinity. However, at micro diversity level the gradual evolution and adaptation might take place (Figure 3) [41]. The analysis of OTUs shared between three soils revealed that bacterial communities from both the saline soils were more similar than that of agriculture soil as depicted by the overlap in Venn diagram of cbbL and 16S rRNA gene clone libraries between the communities at species level cut-off (Additional file 8: Figure S6).