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Size of Dominant Diatom Species Can Alter Their Evenness.

Sugie K, Suzuki K - PLoS ONE (2015)

Bottom Line: We found that the two most useful evenness indices increased in most cases where small species were numerically dominant when calculations were based on biomass compared with those on abundance.The results suggest that the size of the dominant species is a crucial factor in determining the role of diatoms in the ecosystem functioning.Because such size variability can also be observed in other organisms, we need to pay attention to the effect of size structures on biodiversity.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido, Japan; CREST, Japan Science and Technology Agency, Sapporo, Hokkaido, Japan.

ABSTRACT
Traditionally, biodiversity has often been estimated on the basis of abundance partly due to the need for complicated measurements of biomass. Here, we conducted robust measurements of the community composition and of the size structure of diatoms in the North Pacific to evaluate the importance of biomass on the biodiversity. We found that the two most useful evenness indices increased in most cases where small species were numerically dominant when calculations were based on biomass compared with those on abundance. Size-abundance spectra of diatoms revealed that numerically dominant small species rarely dominated in terms of biomass. On the other hand, intermediate to large diatom species generally played a dominant role in terms of biomass in diatom community. The results suggest that the size of the dominant species is a crucial factor in determining the role of diatoms in the ecosystem functioning. Because such size variability can also be observed in other organisms, we need to pay attention to the effect of size structures on biodiversity.

No MeSH data available.


Sampling stations (circles) in the North Pacific with the cruise names.White circle: R/V Hakuho-maru, KH11-10 cruise; Black circle: R/V Hakuho-maru, KH12-3 cruise; Light gray circle: R/V Tansei-maru, KT12-5 cruise; Dark gray circle: R/V Tansei-maru, KT12-31 cruise. Arrows with a #number represent the sample IDs shown in Fig 2.
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pone.0131454.g001: Sampling stations (circles) in the North Pacific with the cruise names.White circle: R/V Hakuho-maru, KH11-10 cruise; Black circle: R/V Hakuho-maru, KH12-3 cruise; Light gray circle: R/V Tansei-maru, KT12-5 cruise; Dark gray circle: R/V Tansei-maru, KT12-31 cruise. Arrows with a #number represent the sample IDs shown in Fig 2.

Mentions: Samples were collected from the North Pacific region (Fig 1). Twenty samples were collected during the R/V Hakuho-maru KH11-10 cruise on December 2011; 34 during the KH12-3 cruise on July–August 2012; 12 during the R/V Tansei-maru KT12-5 cruise on April 2012; 10 during the KT12-31 cruise November 2012; 5 during the T/S Oshoro-maru OS255 cruise on June 2013 (S1 Table). Seawater was collected from the surface (0, 5 or 10 m) and from subsurface chlorophyll maximum layers. For inverted light microscope analysis, acid Lugol’s iodine solution was added to 500 mL of seawater at a final concentration of 4% and 500 mL of seawater was analyzed according to the method of Hasle [30]. For scanning electron microscope analysis, samples were fixed with 10% paraformaldehyde (pH 7.4) at a final concentration of 0.1%. These samples were stored in a refrigerator until on land analysis. Diatom species were identified according to Round et al. [31], and Hasle and Syvertsen [20] and their references. The cell volume of diatom species was measured using the geometric shapes described by Hillebrand et al. [32], and the cell volume was converted to carbon biomass using the allometry reported by Menden-Deuer and Lessard [21]. Because diatoms have large, carbon-poor vacuoles [33], biomass rather than cell volume was used to explore the importance of diatom to the marine ecosystem, such as in their trophic interactions.


Size of Dominant Diatom Species Can Alter Their Evenness.

Sugie K, Suzuki K - PLoS ONE (2015)

Sampling stations (circles) in the North Pacific with the cruise names.White circle: R/V Hakuho-maru, KH11-10 cruise; Black circle: R/V Hakuho-maru, KH12-3 cruise; Light gray circle: R/V Tansei-maru, KT12-5 cruise; Dark gray circle: R/V Tansei-maru, KT12-31 cruise. Arrows with a #number represent the sample IDs shown in Fig 2.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4476557&req=5

pone.0131454.g001: Sampling stations (circles) in the North Pacific with the cruise names.White circle: R/V Hakuho-maru, KH11-10 cruise; Black circle: R/V Hakuho-maru, KH12-3 cruise; Light gray circle: R/V Tansei-maru, KT12-5 cruise; Dark gray circle: R/V Tansei-maru, KT12-31 cruise. Arrows with a #number represent the sample IDs shown in Fig 2.
Mentions: Samples were collected from the North Pacific region (Fig 1). Twenty samples were collected during the R/V Hakuho-maru KH11-10 cruise on December 2011; 34 during the KH12-3 cruise on July–August 2012; 12 during the R/V Tansei-maru KT12-5 cruise on April 2012; 10 during the KT12-31 cruise November 2012; 5 during the T/S Oshoro-maru OS255 cruise on June 2013 (S1 Table). Seawater was collected from the surface (0, 5 or 10 m) and from subsurface chlorophyll maximum layers. For inverted light microscope analysis, acid Lugol’s iodine solution was added to 500 mL of seawater at a final concentration of 4% and 500 mL of seawater was analyzed according to the method of Hasle [30]. For scanning electron microscope analysis, samples were fixed with 10% paraformaldehyde (pH 7.4) at a final concentration of 0.1%. These samples were stored in a refrigerator until on land analysis. Diatom species were identified according to Round et al. [31], and Hasle and Syvertsen [20] and their references. The cell volume of diatom species was measured using the geometric shapes described by Hillebrand et al. [32], and the cell volume was converted to carbon biomass using the allometry reported by Menden-Deuer and Lessard [21]. Because diatoms have large, carbon-poor vacuoles [33], biomass rather than cell volume was used to explore the importance of diatom to the marine ecosystem, such as in their trophic interactions.

Bottom Line: We found that the two most useful evenness indices increased in most cases where small species were numerically dominant when calculations were based on biomass compared with those on abundance.The results suggest that the size of the dominant species is a crucial factor in determining the role of diatoms in the ecosystem functioning.Because such size variability can also be observed in other organisms, we need to pay attention to the effect of size structures on biodiversity.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido, Japan; CREST, Japan Science and Technology Agency, Sapporo, Hokkaido, Japan.

ABSTRACT
Traditionally, biodiversity has often been estimated on the basis of abundance partly due to the need for complicated measurements of biomass. Here, we conducted robust measurements of the community composition and of the size structure of diatoms in the North Pacific to evaluate the importance of biomass on the biodiversity. We found that the two most useful evenness indices increased in most cases where small species were numerically dominant when calculations were based on biomass compared with those on abundance. Size-abundance spectra of diatoms revealed that numerically dominant small species rarely dominated in terms of biomass. On the other hand, intermediate to large diatom species generally played a dominant role in terms of biomass in diatom community. The results suggest that the size of the dominant species is a crucial factor in determining the role of diatoms in the ecosystem functioning. Because such size variability can also be observed in other organisms, we need to pay attention to the effect of size structures on biodiversity.

No MeSH data available.