Phylogenetic and functional potential links pH and N2O emissions in pasture soils
Author
Samad, SainurBiswas, Ambarish
Bakken, Lars R.
Clough, Timothy J.
de Klein, Cecile A.M.
Richards, Karl G.
Lanigan, Gary
Morales, Sergio E.
Keyword
Soil analysispH
Denitrification
N2O emission ratio
community diversity
total denitrification gene (nir & nos)
microbial diversity
Date
26/10/2016
Metadata
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Samad MS, Biswas A, Bakken LR, Clough TJ, de Klein CAM, Richards KG, Lanigan GJ, Morales SE. Phylogenetic and functional potential links pH and N2O emissions in pasture soils. 2016;6:35990; doi 10.1038/srep35990Abstract
Denitrification is mediated by microbial, and physicochemical, processes leading to nitrogen loss via N2O and N2 emissions. Soil pH regulates the reduction of N2O to N2, however, it can also affect microbial community composition and functional potential. Here we simultaneously test the link between pH, community composition, and the N2O emission ratio (N2O/(NO + N2O + N2)) in 13 temperate pasture soils. Physicochemical analysis, gas kinetics, 16S rRNA amplicon sequencing, metagenomic and quantitative PCR (of denitrifier genes: nirS, nirK, nosZI and nosZII) analysis were carried out to characterize each soil. We found strong evidence linking pH to both N2O emission ratio and community changes. Soil pH was negatively associated with N2O emission ratio, while being positively associated with both community diversity and total denitrification gene (nir & nos) abundance. Abundance of nosZII was positively linked to pH, and negatively linked to N2O emissions. Our results confirm that pH imposes a general selective pressure on the entire community and that this results in changes in emission potential. Our data also support the general model that with increased microbial diversity efficiency increases, demonstrated in this study with lowered N2O emission ratio through more efficient conversion of N2O to N2.Funder
New Zealand Fund for Global Partnerships in Livestock Emissions Researchae974a485f413a2113503eed53cd6c53
http://dx.doi.org/10.1038/srep35990