Document Type
Article
Publication Date
4-2022
Keywords
prairie; grassland; nitrogen cycle; soil bacterial community
Abstract
The quantity of grass-root exudates varies by season, suggesting temporal shifts in soil microbial community composition and activity across a growing season. We hypothesized that bacterial community and nitrogen cycle-associated prokaryotic gene expressions shift across three phases of the growing season. To test this hypothesis, we quantified gene and transcript copy number of nitrogen fixation (nifH), ammonia oxidation (amoA, hao, nxrB), denitrification (narG, napA, nirK, nirS, norB, nosZ), dissimilatory nitrate reduction to ammonia (nrfA), and anaerobic ammonium oxidation (hzs, hdh) using the pre-optimized Nitrogen Cycle Evaluation (NiCE) chip. Bacterial community composition was characterized using V3-V4 of the 16S rRNA gene, and PICRUSt2 was used to draw out functional inferences. Surprisingly, the nitrogen cycle genes and transcript quantities were largely stable and unresponsive to seasonal changes. We found that genes and transcripts related to ammonia oxidation and denitrification were different for only one or two time points across the seasons (p < 0.05). However, overall, the nitrogen cycling genes did not show drastic variations. Similarly, the bacterial community also did not vary across the seasons. In contrast, the predicted functional potential was slightly low for May and remained constant for other months. Moreover, soil chemical properties showed a seasonal pattern only for nitrate and ammonium concentrations, while ammonia oxidation and denitrification transcripts were strongly correlated with each other. Hence, the results refuted our assumptions, showing stability in N cycling and bacterial community across growing seasons in a natural grassland.
Publication Title
Microorganisms
Volume
10
Issue
5
First Page
923
DOI of Published Version
10.3390/microorganisms10050923
Publisher
MDPI
Rights
Copyright © 2022 The Authors
Recommended Citation
Das, Bikram Kumar; Ishii, Satoshi; Antony, Linto; Smart, Alexander; Scaria, Joy; and Brozel, Volker, "The Microbial Nitrogen Cycling, Bacterial Community Composition, and Functional Potential in a Natural Grassland Are Stable from Breaking Dormancy to Being Dormant Again" (2022). Native Plant Focused Publications. 31.
https://openprairie.sdstate.edu/nativeplant_pubs/31
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.