Soil microbial community at Takahe Valley (NZ) based on 16S rRNA and nifH amplicon analysis. soil metagenome

In New Zealand indigenous grasslands, legume populations are small and infrequent compared with rangelands worldwide, thus nitrogen fixation by legume-associated microbes is not likely to be significant; as a result non-symbiotic microbes, including cyanobacteria, may make significant contributions to nitrogen fixation. In this study, we examined the diversity of bacteria including free-living nitrogen-fixing communities in indigenous grassland soils. Samples were collected from a long-term study site along a nitrogen gradient in Takahe Valley, situated in South Island, New Zealand. Due to topographic position and soil age, grasslands of Chionochloa snow tussock species form distinct communities that are dominated by individual species. Strong edaphic segregation of Chionochloa species is related to variation in soil nutrients, whereby C. teretifolia and C. pallens are located on sites with low and high total nitrogen availability, respectively. We used metabarcoding to compare the bacterial communities in soil of C. teretifolia- and C. pallens-dominated grasslands.