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Lydia R O'Halloran,
Elizabeth T Borer,
Eric W Seabloom,
Andrew S Macdougall,
Elsa E Cleland,
Rebecca L McCulley,
Sarah Hobbie,
W Stan Harpole,
Nicole M Decrappeo,
Chengjin Chu, [......],
Jennifer Firn,
Nicole Hagenah,
Kirsten S Hofmockel,
Johannes M H Knops,
Wei Li,
Brett A Melbourne,
John W Morgan,
John L Orrock,
Suzanne M Prober, Carly J Stevens
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ABSTRACT: Based on regional-scale studies, aboveground production and litter decomposition are thought to positively covary, because they are driven by shared biotic and climatic factors. Until now we have been unable to test whether production and decomposition are generally coupled across climatically dissimilar regions, because we lacked replicated data collected within a single vegetation type across multiple regions, obfuscating the drivers and generality of the association between production and decomposition. Furthermore, our understanding of the relationships between production and decomposition rests heavily on separate meta-analyses of each response, because no studies have simultaneously measured production and the accumulation or decomposition of litter using consistent methods at globally relevant scales. Here, we use a multi-country grassland dataset collected using a standardized protocol to show that live plant biomass (an estimate of aboveground net primary production) and litter disappearance (represented by mass loss of aboveground litter) do not strongly covary. Live biomass and litter disappearance varied at different spatial scales. There was substantial variation in live biomass among continents, sites and plots whereas among continent differences accounted for most of the variation in litter disappearance rates. Although there were strong associations among aboveground biomass, litter disappearance and climatic factors in some regions (e.g. U.S. Great Plains), these relationships were inconsistent within and among the regions represented by this study. These results highlight the importance of replication among regions and continents when characterizing the correlations between ecosystem processes and interpreting their global-scale implications for carbon flux. We must exercise caution in parameterizing litter decomposition and aboveground production in future regional and global carbon models as their relationship is complex.
PLoS ONE 01/2013; 8(2):e54988. · 4.09 Impact Factor
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James B Grace,
Peter B Adler,
Eric W Seabloom,
Elizabeth T Borer,
Helmut Hillebrand,
Yann Hautier,
Andy Hector,
W Stanley Harpole,
Lydia R O'Halloran,
T Michael Anderson, [......],
John G Lambrinos,
Brett A Melbourne,
Charles E Mitchell,
Joslin L Moore,
John W Morgan,
John L Orrock,
Suzanne M Prober, Carly J Stevens,
Peter D Wragg,
Louie H Yang
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ABSTRACT: Pan et al. claim that our results actually support a strong linear positive relationship between productivity and richness, whereas Fridley et al. contend that the data support a strong humped relationship. These responses illustrate how preoccupation with bivariate patterns distracts from a deeper understanding of the multivariate mechanisms that control these important ecosystem properties.
Science 03/2012; 335(6075):1441. · 31.20 Impact Factor
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Peter B Adler,
Eric W Seabloom,
Elizabeth T Borer,
Helmut Hillebrand,
Yann Hautier,
Andy Hector,
W Stanley Harpole,
Lydia R O'Halloran,
James B Grace,
T Michael Anderson, [......],
David A Pyke,
Anita C Risch,
Martin Schuetz,
Melinda D Smith, Carly J Stevens,
Lauren L Sullivan,
Gang Wang,
Peter D Wragg,
Justin P Wright,
Louie H Yang
[show abstract]
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ABSTRACT: For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the generality of hump-shaped patterns, these syntheses have been criticized for failing to account for methodological differences among studies. We addressed such concerns by conducting standardized sampling in 48 herbaceous-dominated plant communities on five continents. We found no clear relationship between productivity and fine-scale (meters(-2)) richness within sites, within regions, or across the globe. Ecologists should focus on fresh, mechanistic approaches to understanding the multivariate links between productivity and richness.
Science 09/2011; 333(6050):1750-3. · 31.20 Impact Factor
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Jennifer Firn,
Joslin L Moore,
Andrew S MacDougall,
Elizabeth T Borer,
Eric W Seabloom,
Janneke HilleRisLambers,
W Stanley Harpole,
Elsa E Cleland,
Cynthia S Brown,
Johannes M H Knops, [......],
Rebecca McCulley,
Kendi F Davies, Carly J Stevens,
Cheng-Jin Chu,
Karen D Holl,
Julia A Klein,
Philip A Fay,
Nicole Hagenah,
Kevin P Kirkman,
Yvonne M Buckley
[show abstract]
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ABSTRACT: Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites - grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.
Ecology Letters 03/2011; 14(3):274-81. · 17.56 Impact Factor
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Jennifer Firn,
Joslin L. Moore,
Andrew S. MacDougall,
Elizabeth T. Borer,
Eric W. Seabloom,
Janneke HilleRisLambers,
W. Stanley Harpole,
Elsa E. Cleland,
Cynthia S. Brown,
Johannes M. H. Knops, [......],
Rebecca McCulley,
Kendi F. Davies, Carly J. Stevens,
Cheng-Jin Chu,
Karen D. Holl,
Julia A. Klein,
Philip A. Fay,
Nicole Hagenah,
Kevin P. Kirkman,
Yvonne M. Buckley
[show abstract]
[hide abstract]
ABSTRACT: Ecology letters (2011) 14: 274–281AbstractMany ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites – grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.
Ecology Letters 02/2011; 14(3):274 - 281. · 17.56 Impact Factor
