File
Using three pairs of competitive indices to test for changes in plant competition under different resource and disturbance levels
Digital Document
Content type |
Content type
|
---|---|
Collection(s) |
Collection(s)
|
Resource Type |
Resource Type
|
Genre |
Genre
|
Peer Review Status |
Peer Review Status
Peer Reviewed
|
Origin Information |
|
---|
Persons |
---|
Abstract |
Abstract
Questions: How do different resource and disturbance levels interact to affect competition? How do different indices of competition change the interpretation of how competition changes under different resource and disturbance conditions? Location: Greenhouse, Thompson Rivers University, Kamloops, British Columbia, Canada. Methods: Three pairs of indices that have been used to differentiate the predictions of Grime (CSR) and Tilman’s (R*) theories were used to assess competition on two species of temperate bunchgrass, (Pseudorogeneria spicata and Festuca campestris) grown in a greenhouse on stress and disturbance gradients. Stress was created by manipulating the amount of water (high, low) and concentration of nutrient solution (high, low) added to pots, while disturbance was created by clipping (clipped, unclipped) in a fully factorial design. Plants were grown individually or with a single neighbour. The three pairs of indices were: (1) absolute and relative competition; (2) competitive effect and response; and, (3) competitive importance and intensity. Results: Absolute competition and competitive importance were the only indices responsive to the resource gradient, which supports CSR theory, and also the only ones to record an effect of disturbance on the strength of competition – under high resource conditions. The other indices showed few responses along the gradients, which supports R* theory. Measures of competitive effect and response did not differentiate the two theories. Conclusion: We show that some indices of competition show a decline with increased stress and disturbance, while other indices do not. Therefore, it is necessary to choose a competition index appropriate to the question being asked. Competitive importance and absolute competition were responsive to changes in stress and disturbance, while the other indices were not. |
---|---|
Language |
Language
|
Publication Title |
Publication Title
|
---|---|
Publication Number |
Publication Number
Volume 21
|
DOI |
DOI
10.1111/j.1654-1103.2010.01207.x
|
---|---|
Handle |
Handle
Handle placeholder
|
Use and Reproduction |
Use and Reproduction
author
|
---|
Keywords |
Keywords
Absolute and relative competition
Clipping
Competitive effect and response
CSR strategy theory
Drought
Festuca campestris
Importance and intensity of competition
Nutrient availability
Pseudoroegneria spicata
R* theory
|
---|---|
Subject Topic |
tru_60.pdf175.68 KB
126-Extracted Text.txt44.54 KB