Evaluating the relationship between competition and productivity within a native grassland.

Ideas about how plant competition varies with productivity are rooted in classic theories that predict either increasing (Grime) or invariant (Tilman) competition with increasing productivity. Both predictions have received experimental support, although a decade-old meta-analysis supports neither....

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Jonathan A Bennett, James F Cahill
Formato: article
Lenguaje:EN
Publicado: Public Library of Science (PLoS) 2012
Materias:
R
Q
Acceso en línea:https://doaj.org/article/d31466b7ab8743e7b66062a8375d13bf
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:doaj.org-article:d31466b7ab8743e7b66062a8375d13bf
record_format dspace
spelling oai:doaj.org-article:d31466b7ab8743e7b66062a8375d13bf2021-11-18T07:08:04ZEvaluating the relationship between competition and productivity within a native grassland.1932-620310.1371/journal.pone.0043703https://doaj.org/article/d31466b7ab8743e7b66062a8375d13bf2012-01-01T00:00:00Zhttps://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22928021/pdf/?tool=EBIhttps://doaj.org/toc/1932-6203Ideas about how plant competition varies with productivity are rooted in classic theories that predict either increasing (Grime) or invariant (Tilman) competition with increasing productivity. Both predictions have received experimental support, although a decade-old meta-analysis supports neither. Attempts to reconcile the conflicting predictions and evidence include: expanding the theory to include other conditions (e.g. stress gradient hypothesis), development of indices to differentiate either the 'intensity' or 'importance' of competition, a focus on resource supply and demand, and explicit recognition that both growth and survival may exhibit different relationships with productivity. To determine which of these theories accurately predict how competition varies with productivity within a native grassland site, we estimated competitive intensity and relative competitive importance using 22 species across the range of productivity naturally occurring within that site. Plant performance was measured as survival and size with and without neighbours and the local environment was quantified according to variability in standing crop, gross water supply, and net water supply. On average, neighbours weakly facilitated seedling survival, but strongly reduced seedling growth. For both seedling survival and growth, relative competitive importance and competitive intensity declined with some measure of productivity; neighbour effects on survival declined with standing crop, while effects on growth declined with gross water supply. These results add to the growing evidence that plant-plant interactions vary among life history components with different life history components contingent upon separate environmental factors. Although the range of productivity measured in this study was not large, our results do not support the theories of Grime or Tilman. However, our results are consistent with the meta-analysis and parts of other theories, although no single theory is capable of explaining the entirety of these results. This suggests that, at least in moderately productive grasslands, new theory needs to be developed.Jonathan A BennettJames F CahillPublic Library of Science (PLoS)articleMedicineRScienceQENPLoS ONE, Vol 7, Iss 8, p e43703 (2012)
institution DOAJ
collection DOAJ
language EN
topic Medicine
R
Science
Q
spellingShingle Medicine
R
Science
Q
Jonathan A Bennett
James F Cahill
Evaluating the relationship between competition and productivity within a native grassland.
description Ideas about how plant competition varies with productivity are rooted in classic theories that predict either increasing (Grime) or invariant (Tilman) competition with increasing productivity. Both predictions have received experimental support, although a decade-old meta-analysis supports neither. Attempts to reconcile the conflicting predictions and evidence include: expanding the theory to include other conditions (e.g. stress gradient hypothesis), development of indices to differentiate either the 'intensity' or 'importance' of competition, a focus on resource supply and demand, and explicit recognition that both growth and survival may exhibit different relationships with productivity. To determine which of these theories accurately predict how competition varies with productivity within a native grassland site, we estimated competitive intensity and relative competitive importance using 22 species across the range of productivity naturally occurring within that site. Plant performance was measured as survival and size with and without neighbours and the local environment was quantified according to variability in standing crop, gross water supply, and net water supply. On average, neighbours weakly facilitated seedling survival, but strongly reduced seedling growth. For both seedling survival and growth, relative competitive importance and competitive intensity declined with some measure of productivity; neighbour effects on survival declined with standing crop, while effects on growth declined with gross water supply. These results add to the growing evidence that plant-plant interactions vary among life history components with different life history components contingent upon separate environmental factors. Although the range of productivity measured in this study was not large, our results do not support the theories of Grime or Tilman. However, our results are consistent with the meta-analysis and parts of other theories, although no single theory is capable of explaining the entirety of these results. This suggests that, at least in moderately productive grasslands, new theory needs to be developed.
format article
author Jonathan A Bennett
James F Cahill
author_facet Jonathan A Bennett
James F Cahill
author_sort Jonathan A Bennett
title Evaluating the relationship between competition and productivity within a native grassland.
title_short Evaluating the relationship between competition and productivity within a native grassland.
title_full Evaluating the relationship between competition and productivity within a native grassland.
title_fullStr Evaluating the relationship between competition and productivity within a native grassland.
title_full_unstemmed Evaluating the relationship between competition and productivity within a native grassland.
title_sort evaluating the relationship between competition and productivity within a native grassland.
publisher Public Library of Science (PLoS)
publishDate 2012
url https://doaj.org/article/d31466b7ab8743e7b66062a8375d13bf
work_keys_str_mv AT jonathanabennett evaluatingtherelationshipbetweencompetitionandproductivitywithinanativegrassland
AT jamesfcahill evaluatingtherelationshipbetweencompetitionandproductivitywithinanativegrassland
_version_ 1718423945821028352