Limits...
Distinct soil bacterial communities along a small-scale elevational gradient in alpine tundra.

Shen C, Ni Y, Liang W, Wang J, Chu H - Front Microbiol (2015)

Bottom Line: Bacterial communities were more phylogenetically clustered than expected by chance at all elevations based on the standardized effect size of MNTD metric.Taken together, this is the first time that a significant bacterial diversity pattern has been observed across a small-scale elevational gradient.Our results indicated that soil carbon and nitrogen contents were the critical environmental factors affecting bacterial elevational distribution in Changbai Mountain tundra.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing China ; University of Chinese Academy of Sciences, Beijing China.

ABSTRACT
The elevational diversity pattern for microorganisms has received great attention recently but is still understudied, and phylogenetic relatedness is rarely studied for microbial elevational distributions. Using a bar-coded pyrosequencing technique, we examined the biodiversity patterns for soil bacterial communities of tundra ecosystem along 2000-2500 m elevations on Changbai Mountain in China. Bacterial taxonomic richness displayed a linear decreasing trend with increasing elevation. Phylogenetic diversity and mean nearest taxon distance (MNTD) exhibited a unimodal pattern with elevation. Bacterial communities were more phylogenetically clustered than expected by chance at all elevations based on the standardized effect size of MNTD metric. The bacterial communities differed dramatically among elevations, and the community composition was significantly correlated with soil total carbon (TC), total nitrogen, C:N ratio, and dissolved organic carbon. Multiple ordinary least squares regression analysis showed that the observed biodiversity patterns strongly correlated with soil TC and C:N ratio. Taken together, this is the first time that a significant bacterial diversity pattern has been observed across a small-scale elevational gradient. Our results indicated that soil carbon and nitrogen contents were the critical environmental factors affecting bacterial elevational distribution in Changbai Mountain tundra. This suggested that ecological niche-based environmental filtering processes related to soil carbon and nitrogen contents could play a dominant role in structuring bacterial communities along the elevational gradient.

No MeSH data available.


Related in: MedlinePlus

The relative abundances of the dominant bacterial phyla at each elevation in relation to soil total carbon (TC). The strength of each relationship given is based on the linear regression equation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493907&req=5

Figure 3: The relative abundances of the dominant bacterial phyla at each elevation in relation to soil total carbon (TC). The strength of each relationship given is based on the linear regression equation.

Mentions: Canonical correspondence analysis showed that elevation had the strongest effect (longer arrow) on bacterial community composition (Figure 2B). Of all the environmental variables tested, elevation was the most highly correlated with community composition (r = 0.64, P = 0.001, Table 2). These results suggest that elevation could be a good predictor of variation in bacterial community composition. Other factors such as TC, TN, C:N ratio, and DOC, also showed a high correlation with bacterial community composition based on Mantel test (Table 2). Specifically, significant relationships were found between the relative abundance of each taxonomic group and soil carbon and nitrogen contents (Supplementary Table S5). For example, the relative abundance of Alphaproteobacteria, Actinobacteria increased with TC, whereas the relative abundance of Betaproteobacteria, Gammaproteobacteria, and Bacteroidetes showed the opposite pattern. Even Verrucomicrobia, which had relatively low abundances, were significantly correlated with TC (Figure 3). Surprisingly, the relative abundance of Acidobacteria was significantly correlated with soil pH, despite the narrow pH ranges in these soils (Figure 1; Supplementary Table S5).


Distinct soil bacterial communities along a small-scale elevational gradient in alpine tundra.

Shen C, Ni Y, Liang W, Wang J, Chu H - Front Microbiol (2015)

The relative abundances of the dominant bacterial phyla at each elevation in relation to soil total carbon (TC). The strength of each relationship given is based on the linear regression equation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493907&req=5

Figure 3: The relative abundances of the dominant bacterial phyla at each elevation in relation to soil total carbon (TC). The strength of each relationship given is based on the linear regression equation.
Mentions: Canonical correspondence analysis showed that elevation had the strongest effect (longer arrow) on bacterial community composition (Figure 2B). Of all the environmental variables tested, elevation was the most highly correlated with community composition (r = 0.64, P = 0.001, Table 2). These results suggest that elevation could be a good predictor of variation in bacterial community composition. Other factors such as TC, TN, C:N ratio, and DOC, also showed a high correlation with bacterial community composition based on Mantel test (Table 2). Specifically, significant relationships were found between the relative abundance of each taxonomic group and soil carbon and nitrogen contents (Supplementary Table S5). For example, the relative abundance of Alphaproteobacteria, Actinobacteria increased with TC, whereas the relative abundance of Betaproteobacteria, Gammaproteobacteria, and Bacteroidetes showed the opposite pattern. Even Verrucomicrobia, which had relatively low abundances, were significantly correlated with TC (Figure 3). Surprisingly, the relative abundance of Acidobacteria was significantly correlated with soil pH, despite the narrow pH ranges in these soils (Figure 1; Supplementary Table S5).

Bottom Line: Bacterial communities were more phylogenetically clustered than expected by chance at all elevations based on the standardized effect size of MNTD metric.Taken together, this is the first time that a significant bacterial diversity pattern has been observed across a small-scale elevational gradient.Our results indicated that soil carbon and nitrogen contents were the critical environmental factors affecting bacterial elevational distribution in Changbai Mountain tundra.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing China ; University of Chinese Academy of Sciences, Beijing China.

ABSTRACT
The elevational diversity pattern for microorganisms has received great attention recently but is still understudied, and phylogenetic relatedness is rarely studied for microbial elevational distributions. Using a bar-coded pyrosequencing technique, we examined the biodiversity patterns for soil bacterial communities of tundra ecosystem along 2000-2500 m elevations on Changbai Mountain in China. Bacterial taxonomic richness displayed a linear decreasing trend with increasing elevation. Phylogenetic diversity and mean nearest taxon distance (MNTD) exhibited a unimodal pattern with elevation. Bacterial communities were more phylogenetically clustered than expected by chance at all elevations based on the standardized effect size of MNTD metric. The bacterial communities differed dramatically among elevations, and the community composition was significantly correlated with soil total carbon (TC), total nitrogen, C:N ratio, and dissolved organic carbon. Multiple ordinary least squares regression analysis showed that the observed biodiversity patterns strongly correlated with soil TC and C:N ratio. Taken together, this is the first time that a significant bacterial diversity pattern has been observed across a small-scale elevational gradient. Our results indicated that soil carbon and nitrogen contents were the critical environmental factors affecting bacterial elevational distribution in Changbai Mountain tundra. This suggested that ecological niche-based environmental filtering processes related to soil carbon and nitrogen contents could play a dominant role in structuring bacterial communities along the elevational gradient.

No MeSH data available.


Related in: MedlinePlus