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Aboveground herbivory shapes the biomass distribution and flux of soil invertebrates.

Mulder C, Den Hollander HA, Hendriks AJ - PLoS ONE (2008)

Bottom Line: Overall higher biomasses of invertebrates occur in grasslands, and all larger soil organisms differed remarkably.Strong statistical evidence supports a hypothesis explaining from an allometric perspective how the faunal biomass distribution and the energetic flux are affected by livestock, nutrient availability and land use.Our aim is to propose faunal biomass flux and biomass distribution as quantitative descriptors of soil community composition and function, and to illustrate the application of these allometric indicators to soil systems.

View Article: PubMed Central - PubMed

Affiliation: Department of Ecology, National Institute for Public Health and the Environment, RIVM-LER, Bilthoven, The Netherlands. Christian.Mulder@rivm.nl

ABSTRACT

Background: Living soil invertebrates provide a universal currency for quality that integrates physical and chemical variables with biogeography as the invertebrates reflect their habitat and most ecological changes occurring therein. The specific goal was the identification of "reference" states for soil sustainability and ecosystem functioning in grazed vs. ungrazed sites.

Methodology/principal findings: Bacterial cells were counted by fluorescent staining and combined direct microscopy and automatic image analysis; invertebrates (nematodes, mites, insects, oligochaetes) were sampled and their body size measured individually to allow allometric scaling. Numerical allometry analyses food webs by a direct comparison of weight averages of components and thus might characterize the detrital soil food webs of our 135 sites regardless of taxonomy. Sharp differences in the frequency distributions are shown. Overall higher biomasses of invertebrates occur in grasslands, and all larger soil organisms differed remarkably.

Conclusions/significance: Strong statistical evidence supports a hypothesis explaining from an allometric perspective how the faunal biomass distribution and the energetic flux are affected by livestock, nutrient availability and land use. Our aim is to propose faunal biomass flux and biomass distribution as quantitative descriptors of soil community composition and function, and to illustrate the application of these allometric indicators to soil systems.

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Related in: MedlinePlus

Linear binning and classic allometry are closely correlated.The arbitrary class interval of the log(M) bins for our 135 real webs is 0.2 with constant linear width. In contrast to the simulation results of White et al. [43], who generated power-law distributed random numbers using inverse transformation for the Pareto distribution [8], [43], the linear binning performed very well in our empirical study.
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pone-0003573-g001: Linear binning and classic allometry are closely correlated.The arbitrary class interval of the log(M) bins for our 135 real webs is 0.2 with constant linear width. In contrast to the simulation results of White et al. [43], who generated power-law distributed random numbers using inverse transformation for the Pareto distribution [8], [43], the linear binning performed very well in our empirical study.

Mentions: The allometric analyses showed that log(N), log(M), and log(B) are strictly correlated in our soil systems, as theoretically expected from lakes [8], [27]. The allometric size-abundance slopes (NMS, i.e. Numerical abundance as function of dry Mass averages) were always negative, whereas the faunal biomass–size slopes (FBS) were always positive in the investigated body-size range of our 135 soil systems. Merging the classic allometric formula log(N) = a×log(M)+b [25], [27] with log(B) = log(M)+log(N), we obtain log(B) = log(M)+a×log(M)+b = (1+a)×log(M)+b. Thus, both allometric slopes, NMS and FBS, are closely correlated (Figure 1, R2 = 74%, p<10−43).


Aboveground herbivory shapes the biomass distribution and flux of soil invertebrates.

Mulder C, Den Hollander HA, Hendriks AJ - PLoS ONE (2008)

Linear binning and classic allometry are closely correlated.The arbitrary class interval of the log(M) bins for our 135 real webs is 0.2 with constant linear width. In contrast to the simulation results of White et al. [43], who generated power-law distributed random numbers using inverse transformation for the Pareto distribution [8], [43], the linear binning performed very well in our empirical study.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2570614&req=5

pone-0003573-g001: Linear binning and classic allometry are closely correlated.The arbitrary class interval of the log(M) bins for our 135 real webs is 0.2 with constant linear width. In contrast to the simulation results of White et al. [43], who generated power-law distributed random numbers using inverse transformation for the Pareto distribution [8], [43], the linear binning performed very well in our empirical study.
Mentions: The allometric analyses showed that log(N), log(M), and log(B) are strictly correlated in our soil systems, as theoretically expected from lakes [8], [27]. The allometric size-abundance slopes (NMS, i.e. Numerical abundance as function of dry Mass averages) were always negative, whereas the faunal biomass–size slopes (FBS) were always positive in the investigated body-size range of our 135 soil systems. Merging the classic allometric formula log(N) = a×log(M)+b [25], [27] with log(B) = log(M)+log(N), we obtain log(B) = log(M)+a×log(M)+b = (1+a)×log(M)+b. Thus, both allometric slopes, NMS and FBS, are closely correlated (Figure 1, R2 = 74%, p<10−43).

Bottom Line: Overall higher biomasses of invertebrates occur in grasslands, and all larger soil organisms differed remarkably.Strong statistical evidence supports a hypothesis explaining from an allometric perspective how the faunal biomass distribution and the energetic flux are affected by livestock, nutrient availability and land use.Our aim is to propose faunal biomass flux and biomass distribution as quantitative descriptors of soil community composition and function, and to illustrate the application of these allometric indicators to soil systems.

View Article: PubMed Central - PubMed

Affiliation: Department of Ecology, National Institute for Public Health and the Environment, RIVM-LER, Bilthoven, The Netherlands. Christian.Mulder@rivm.nl

ABSTRACT

Background: Living soil invertebrates provide a universal currency for quality that integrates physical and chemical variables with biogeography as the invertebrates reflect their habitat and most ecological changes occurring therein. The specific goal was the identification of "reference" states for soil sustainability and ecosystem functioning in grazed vs. ungrazed sites.

Methodology/principal findings: Bacterial cells were counted by fluorescent staining and combined direct microscopy and automatic image analysis; invertebrates (nematodes, mites, insects, oligochaetes) were sampled and their body size measured individually to allow allometric scaling. Numerical allometry analyses food webs by a direct comparison of weight averages of components and thus might characterize the detrital soil food webs of our 135 sites regardless of taxonomy. Sharp differences in the frequency distributions are shown. Overall higher biomasses of invertebrates occur in grasslands, and all larger soil organisms differed remarkably.

Conclusions/significance: Strong statistical evidence supports a hypothesis explaining from an allometric perspective how the faunal biomass distribution and the energetic flux are affected by livestock, nutrient availability and land use. Our aim is to propose faunal biomass flux and biomass distribution as quantitative descriptors of soil community composition and function, and to illustrate the application of these allometric indicators to soil systems.

Show MeSH
Related in: MedlinePlus