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Published on: March 13, 2014
Species-specific traits rather than resource partitioning mediate diversity effects on resource use.
Jasmin A Godbold1, Rutger Rosenberg, Martin Solan
1Oceanlab, University of Aberdeen, Newburgh, Aberdeenshire, United Kingdom. j.a.godbold@abdn.ac.uk
Plos One
|October 16, 2009
Summary
Marine echinoderms do not partition food resources at the biochemical level. Increased total resource use in diverse treatments was driven by selection effects and species dominance, not resource partitioning.
Area of Science:
- Marine Ecology
- Biodiversity and Ecosystem Function
- Benthic Ecology
Background:
- The relationship between biodiversity and ecosystem processes is well-established, but underlying mechanisms remain unclear.
- Previous research often focused on terrestrial systems, with limited resolution to detect biochemical-level resource partitioning.
- Species-specific nutritional niches at the biochemical level may influence diversity effects on resource use.
Purpose of the Study:
- To investigate if resource partitioning is the primary mechanism driving diversity effects on resource use in marine benthic echinoderms.
- To determine if three co-occurring echinoderm species (Brissopsis lyrifera, Mesothuria intestinalis, Parastichopus tremulus) partition phytodetrital food resources at the biochemical level.
- To analyze the use of phytodetrital pigments (chlorophylls and carotenoids) as indicators of resource partitioning.
Main Methods:
- Analysis of three co-occurring marine benthic echinoderms feeding on the same phytodetrital source.
- Quantification of phytodetrital pigments using reverse-phase high-performance liquid chromatography (HPLC).
- Statistical analysis combining extended linear regression with generalized least squares (GLS) estimation and multivariate techniques.
Main Results:
- No species-specific selectivity for particular algal pigments was observed, indicating no resource partitioning at the biochemical level.
- Pigment composition was similar across individuals, suggesting plentiful food availability.
- Increased total resource use in diverse treatments was observed, attributed to selection effects and the dominance of Brissopsis lyrifera.
Conclusions:
- Resource partitioning at the biochemical level was not supported for the studied echinoderm species.
- Selection effects and species dominance, particularly by B. lyrifera, explained increased resource use in mixed-species treatments.
- Reduced intra-specific competition, enhanced adsorption efficiency, and differing feeding behaviors likely contributed to B. lyrifera's resource dominance.
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