| Title |
Symbiotic N2-Fixer Community Composition, but Not Diversity, Shifts in Nodules of a Single Host Legume Across a 2-Million-Year Dune Chronosequence
|
|---|---|
| Published in |
Microbial Ecology, April 2018
|
| DOI | 10.1007/s00248-018-1185-1 |
| Pubmed ID | |
| Authors |
Christina Birnbaum, Andrew Bissett, Francois P. Teste, Etienne Laliberté |
| Abstract |
Long-term soil age gradients are useful model systems to study how changes in nutrient limitation shape communities of plant root mutualists because they represent strong natural gradients of nutrient availability, particularly of nitrogen (N) and phosphorus (P). Here, we investigated changes in the dinitrogen (N2)-fixing bacterial community composition and diversity in nodules of a single host legume (Acacia rostellifera) across the Jurien Bay chronosequence, a retrogressive 2 million-year-old sequence of coastal dunes representing an exceptionally strong natural soil fertility gradient. We collected nodules from plants grown in soils from five chronosequence stages ranging from very young (10s of years; associated with strong N limitation for plant growth) to very old (> 2,000,000 years; associated with strong P limitation), and sequenced the nifH gene in root nodules to determine the composition and diversity of N2-fixing bacterial symbionts. A total of 335 unique nifH gene operational taxonomic units (OTUs) were identified. Community composition of N2-fixing bacteria within nodules, but not diversity, changed with increasing soil age. These changes were attributed to pedogenesis-driven shifts in edaphic conditions, specifically pH, exchangeable manganese, resin-extractable phosphate, nitrate and nitrification rate. A large number of common N2-fixing bacteria genera (e.g. Bradyrhizobium, Ensifer, Mesorhizobium and Rhizobium) belonging to the Rhizobiaceae family (α-proteobacteria) comprised 70% of all raw sequences and were present in all nodules. However, the oldest soils, which show some of the lowest soil P availability ever recorded, harboured the largest proportion of unclassified OTUs, suggesting a unique set of N2-fixing bacteria adapted to extreme P limitation. Our results show that N2-fixing bacterial composition varies strongly during long-term ecosystem development, even within the same host, and therefore rhizobia show strong edaphic preferences. |
X Demographics
The data shown below were collected from the profiles of 8 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Australia | 3 | 38% |
| Germany | 1 | 13% |
| United States | 1 | 13% |
| New Zealand | 1 | 13% |
| Unknown | 2 | 25% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 5 | 63% |
| Scientists | 3 | 38% |
Mendeley readers
The data shown below were compiled from readership statistics for 24 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 24 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 6 | 25% |
| Student > Bachelor | 2 | 8% |
| Researcher | 2 | 8% |
| Student > Doctoral Student | 1 | 4% |
| Other | 1 | 4% |
| Other | 4 | 17% |
| Unknown | 8 | 33% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 9 | 38% |
| Environmental Science | 3 | 13% |
| Computer Science | 1 | 4% |
| Immunology and Microbiology | 1 | 4% |
| Medicine and Dentistry | 1 | 4% |
| Other | 0 | 0% |
| Unknown | 9 | 38% |
Attention Score in Context
This research output has an Altmetric Attention Score of 5. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 04 July 2018.
All research outputs
#6,285,277
of 23,043,346 outputs
Outputs from Microbial Ecology
#657
of 2,069 outputs
Outputs of similar age
#100,419
of 296,868 outputs
Outputs of similar age from Microbial Ecology
#18
of 37 outputs
Altmetric has tracked 23,043,346 research outputs across all sources so far. This one has received more attention than most of these and is in the 72nd percentile.
So far Altmetric has tracked 2,069 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 5.4. This one has gotten more attention than average, scoring higher than 68% of its peers.
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We're also able to compare this research output to 37 others from the same source and published within six weeks on either side of this one. This one has gotten more attention than average, scoring higher than 51% of its contemporaries.