Limits...
Effects of Spartina alterniflora invasion on the communities of methanogens and sulfate-reducing bacteria in estuarine marsh sediments.

Zeleke J, Sheng Q, Wang JG, Huang MY, Xia F, Wu JH, Quan ZX - Front Microbiol (2013)

Bottom Line: Similar trends were observed for SRB, and they were up to two orders of magnitude higher than the methanogens.Diversity indices indicated a lower diversity of methanogens in the S. alterniflora stands than the P. australis stands.The results showed that in the sediments of tidal salt marsh where S. alterniflora displaced P. australis, the abundances of methanogens and SRB increased, but the community composition of methanogens appeared to be influenced more than did the SRB.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University Shanghai, China.

ABSTRACT
The effect of plant invasion on the microorganisms of soil sediments is very important for estuary ecology. The community structures of methanogens and sulfate-reducing bacteria (SRB) as a function of Spartina alterniflora invasion in Phragmites australis-vegetated sediments of the Dongtan wetland in the Yangtze River estuary, China, were investigated using 454 pyrosequencing and quantitative real-time PCR (qPCR) of the methyl coenzyme M reductase A (mcrA) and dissimilatory sulfite-reductase (dsrB) genes. Sediment samples were collected from two replicate locations, and each location included three sampling stands each covered by monocultures of P. australis, S. alterniflora and both plants (transition stands), respectively. qPCR analysis revealed higher copy numbers of mcrA genes in sediments from S. alterniflora stands than P. australis stands (5- and 7.5-fold more in the spring and summer, respectively), which is consistent with the higher methane flux rates measured in the S. alterniflora stands (up to 8.01 ± 5.61 mg m(-2) h(-1)). Similar trends were observed for SRB, and they were up to two orders of magnitude higher than the methanogens. Diversity indices indicated a lower diversity of methanogens in the S. alterniflora stands than the P. australis stands. In contrast, insignificant variations were observed in the diversity of SRB with the invasion. Although Methanomicrobiales and Methanococcales, the hydrogenotrophic methanogens, dominated in the salt marsh, Methanomicrobiales displayed a slight increase with the invasion and growth of S. alterniflora, whereas the later responded differently. Methanosarcina, the metabolically diverse methanogens, did not vary with the invasion of, but Methanosaeta, the exclusive acetate utilizers, appeared to increase with S. alterniflora invasion. In SRB, sequences closely related to the families Desulfobacteraceae and Desulfobulbaceae dominated in the salt marsh, although they displayed minimal changes with the S. alterniflora invasion. Approximately 11.3 ± 5.1% of the dsrB gene sequences formed a novel cluster that was reduced upon the invasion. The results showed that in the sediments of tidal salt marsh where S. alterniflora displaced P. australis, the abundances of methanogens and SRB increased, but the community composition of methanogens appeared to be influenced more than did the SRB.

No MeSH data available.


Related in: MedlinePlus

Methane and carbon dioxide flux rates in the P. australis (P), S. alterniflora (S) and transition (T) stands in the Dongtan salt marsh located in the Yangtze River estuary. In the sample names, I and II represent the spring and summer samples, respectively, whereas “a” and “b” indicate the replicate locations.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3750361&req=5

Figure 1: Methane and carbon dioxide flux rates in the P. australis (P), S. alterniflora (S) and transition (T) stands in the Dongtan salt marsh located in the Yangtze River estuary. In the sample names, I and II represent the spring and summer samples, respectively, whereas “a” and “b” indicate the replicate locations.

Mentions: Methane flux rates differed both with the invasion and growth of S. alterniflora (Figure 1). In spring, the mean flux rates in the P. australis, transition, and S. alterniflora stands were approximately 0.51 ± 0.31, 0.93 ± 0.37, and 0.99 ± 0.35 mg m−2 h−1, respectively. This indicates an approximately 97% increase of flux rate with S. alterniflora invasion. When the plants were fully grown, these flux rates were increased to 1.63 ± 0.34, 4.11 ± 2.49, and 8.01 ± 5.61 mg m−2 h−1, respectively, in the P. australis, transition and S. alterniflora stands and the impact of S. alterniflora was significant in the summer (152 and 391% higher in the transition and S. alterniflora strands, respectively, than in P. australis stands). The gas flux rates also displayed significant increases in the summer (225, 343, and 709% in the P. australis, transition and S. alterniflora stands, respectively). These increases were positively correlated with the change in temperatures (R2 = 0.2, α = 0.05), although not significant. Similarly, carbon dioxide flux rates were relatively high in the S. alterniflora stands. When the mean flux ratios of methane to carbon dioxide were compared, higher values were observed in the S. alterniflora stands than in the P. australis stands. In spring, the ratios were approximately 9 × 10−4 and 3 × 10−3, in the P. australis and S. alterniflora stands, respectively, representing an approximate 3.5-fold increase in the S. alterniflora stands (Figure 1). In summer, these ratios were approximately 1.74 × 10−3 and 3.6 × 10−3, in the P. australis and S. alterniflora stands, respectively, representing an increase of approximately 2.1-fold in the S. alterniflora stands.


Effects of Spartina alterniflora invasion on the communities of methanogens and sulfate-reducing bacteria in estuarine marsh sediments.

Zeleke J, Sheng Q, Wang JG, Huang MY, Xia F, Wu JH, Quan ZX - Front Microbiol (2013)

Methane and carbon dioxide flux rates in the P. australis (P), S. alterniflora (S) and transition (T) stands in the Dongtan salt marsh located in the Yangtze River estuary. In the sample names, I and II represent the spring and summer samples, respectively, whereas “a” and “b” indicate the replicate locations.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3750361&req=5

Figure 1: Methane and carbon dioxide flux rates in the P. australis (P), S. alterniflora (S) and transition (T) stands in the Dongtan salt marsh located in the Yangtze River estuary. In the sample names, I and II represent the spring and summer samples, respectively, whereas “a” and “b” indicate the replicate locations.
Mentions: Methane flux rates differed both with the invasion and growth of S. alterniflora (Figure 1). In spring, the mean flux rates in the P. australis, transition, and S. alterniflora stands were approximately 0.51 ± 0.31, 0.93 ± 0.37, and 0.99 ± 0.35 mg m−2 h−1, respectively. This indicates an approximately 97% increase of flux rate with S. alterniflora invasion. When the plants were fully grown, these flux rates were increased to 1.63 ± 0.34, 4.11 ± 2.49, and 8.01 ± 5.61 mg m−2 h−1, respectively, in the P. australis, transition and S. alterniflora stands and the impact of S. alterniflora was significant in the summer (152 and 391% higher in the transition and S. alterniflora strands, respectively, than in P. australis stands). The gas flux rates also displayed significant increases in the summer (225, 343, and 709% in the P. australis, transition and S. alterniflora stands, respectively). These increases were positively correlated with the change in temperatures (R2 = 0.2, α = 0.05), although not significant. Similarly, carbon dioxide flux rates were relatively high in the S. alterniflora stands. When the mean flux ratios of methane to carbon dioxide were compared, higher values were observed in the S. alterniflora stands than in the P. australis stands. In spring, the ratios were approximately 9 × 10−4 and 3 × 10−3, in the P. australis and S. alterniflora stands, respectively, representing an approximate 3.5-fold increase in the S. alterniflora stands (Figure 1). In summer, these ratios were approximately 1.74 × 10−3 and 3.6 × 10−3, in the P. australis and S. alterniflora stands, respectively, representing an increase of approximately 2.1-fold in the S. alterniflora stands.

Bottom Line: Similar trends were observed for SRB, and they were up to two orders of magnitude higher than the methanogens.Diversity indices indicated a lower diversity of methanogens in the S. alterniflora stands than the P. australis stands.The results showed that in the sediments of tidal salt marsh where S. alterniflora displaced P. australis, the abundances of methanogens and SRB increased, but the community composition of methanogens appeared to be influenced more than did the SRB.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University Shanghai, China.

ABSTRACT
The effect of plant invasion on the microorganisms of soil sediments is very important for estuary ecology. The community structures of methanogens and sulfate-reducing bacteria (SRB) as a function of Spartina alterniflora invasion in Phragmites australis-vegetated sediments of the Dongtan wetland in the Yangtze River estuary, China, were investigated using 454 pyrosequencing and quantitative real-time PCR (qPCR) of the methyl coenzyme M reductase A (mcrA) and dissimilatory sulfite-reductase (dsrB) genes. Sediment samples were collected from two replicate locations, and each location included three sampling stands each covered by monocultures of P. australis, S. alterniflora and both plants (transition stands), respectively. qPCR analysis revealed higher copy numbers of mcrA genes in sediments from S. alterniflora stands than P. australis stands (5- and 7.5-fold more in the spring and summer, respectively), which is consistent with the higher methane flux rates measured in the S. alterniflora stands (up to 8.01 ± 5.61 mg m(-2) h(-1)). Similar trends were observed for SRB, and they were up to two orders of magnitude higher than the methanogens. Diversity indices indicated a lower diversity of methanogens in the S. alterniflora stands than the P. australis stands. In contrast, insignificant variations were observed in the diversity of SRB with the invasion. Although Methanomicrobiales and Methanococcales, the hydrogenotrophic methanogens, dominated in the salt marsh, Methanomicrobiales displayed a slight increase with the invasion and growth of S. alterniflora, whereas the later responded differently. Methanosarcina, the metabolically diverse methanogens, did not vary with the invasion of, but Methanosaeta, the exclusive acetate utilizers, appeared to increase with S. alterniflora invasion. In SRB, sequences closely related to the families Desulfobacteraceae and Desulfobulbaceae dominated in the salt marsh, although they displayed minimal changes with the S. alterniflora invasion. Approximately 11.3 ± 5.1% of the dsrB gene sequences formed a novel cluster that was reduced upon the invasion. The results showed that in the sediments of tidal salt marsh where S. alterniflora displaced P. australis, the abundances of methanogens and SRB increased, but the community composition of methanogens appeared to be influenced more than did the SRB.

No MeSH data available.


Related in: MedlinePlus