Importance of methane-derived carbon as a basal resource for two benthic consumers in arctic lakes

Autor: Anne E. Hershey, Cassandra A. Medvedeff
Rok vydání: 2012
Předmět:
Zdroj: Hydrobiologia. 700:221-230
ISSN: 1573-5117
0018-8158
DOI: 10.1007/s10750-012-1232-8
Popis: Microbial processing of detritus is known to be important to benthic invertebrate nutrition, but the role of dissolved (DOC) versus particulate organic carbon (POC), and pathways by which those resources are obtained, are poorly understood. We used stable isotopes to determine the importance of DOC, POC, and CH4-derived carbon to benthic invertebrate consumers from arctic Alaskan Lakes. Intact sediment cores from Lake GTH 112 were enriched with 13C-labeled organic matter, including algal detritus, algal-derived DOC, methyl-labeled acetate, and carboxyl-labeled acetate, and incubated for 1 month with either caddisflies (Grensia praeterita ) or fingernail clams (Sphaerium nitidum), two invertebrate species that are important to fish nutrition. Both species used basal resources derived from POC and DOC. Results generally suggest greater reliance on POC. Differential assimilation from acetate treatments suggests Sphaerium assimilated CH4-derived carbon, which likely occurred through deposit-feeding. Grensia assimilated some microbially processed acetate, although its survivorship was poor in acetate treatments. Our data extend previous studies reporting use of CH4-derived carbon by Chironomidae and oligochaetes. Taken together, these results suggest that the use of CH4-derived carbon is common among deposit-feeding benthic invertebrates.
Databáze: OpenAIRE
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