Food chain efficiency ( We conducted a large‐scale, 6‐week mesocosm experiment in which we manipulated light and nutrient (nitrogen and phosphorus) supply and the identity of the carnivore in a 2 × 2 × 2 factorial design. We quantified the response of We predicted that bluegill would be more likely to experience P‐limitation due to higher P requirements, and hence that Carnivore identity mediated the effects of light and nutrients on Comparison of our results with those from previous experiments showed that
Dissolved organic matter ( The effects of experimental additions of terrestrially derived The increase in zooplankton biomass during the experiment was similar in magnitude to the total amount of dissolved organic carbon ( The role of nutrients needs to be considered when examining the response of pelagic ecosystems to inputs of terrestrial
- NSF-PAR ID:
- 10031398
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Freshwater Biology
- Volume:
- 62
- Issue:
- 1
- ISSN:
- 0046-5070
- Page Range / eLocation ID:
- p. 40-51
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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DOC sources were evaluated separately, decomposition rates were higher in treatments with algalDOC only than with fenDOC only, indicating that the quality of the organic matter influenced degradability. A mixture of substrates (½ algalDOC + ½ fenDOC ) exceeded the expected level of biodegradation (i.e. the average of the individual substrate responses) by as much as 10%, and the magnitude of this effect increased to more than 15% with warming.Specific ultraviolet absorbance at 254 nm (SUVA254), a proxy for aromatic content, was also significantly higher (i.e. more humic) in the mixture treatment than expected from SUVA254values in single substrate treatments.
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Summary Autotrophic respiration is a major driver of the global C cycle and may contribute a positive climate warming feedback through increased atmospheric concentrations of
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