The American Midland Naturalist
نویسندگان
چکیده
—Defining the trophic position of stream organisms is a first step in understanding the ecology of lotic systems. Whereas trophic positions of stream fishes have been traditionally assigned based on dietary analysis, stable isotope ratios may provide additional information on the validity of this approach and may be used to verify energy acquisition assumed from dietary studies. In this study, we assessed the concordance of literature-based trophic classifications and isotopic dN signatures for small-bodied fishes from four streams in Kansas, Oklahoma and New Mexico. ANOVA results revealed no significant difference (F2,271⁄41.71, P1⁄40.201) in trophic position based on dN values among three broad trophic classifications derived from literature sources (algivores/detritivores, omnivores and invertivores). Both the prevalence of omnivory in stream fishes and potential biases associated with isotope fractionation at different trophic levels poses potential problems when classifying lotic fish into trophic positions.
منابع مشابه
Biomass and Toxicity Responses of Poison Ivy (toxicodendron Radicans) to Elevated Atmospheric Co2: Reply
tailed deer, Odocoileus virginianus, in Martin County, Indiana. American Midland Naturalist 89:281–286. Sperry, J. S., N. M. Holbrook, M. H. Zimmerman, and M. T. Tyree. 1987. Spring filling of xylem vessels in wild grapevine. Plant Physiology 83:414–417. Stiles, E. W. 1982. Fruit flags: two hypotheses. American Naturalist 120:500–509. Walters, M. B., and P. B. Reich. 2000. Seed size, nitrogen s...
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متن کاملThe American Midland Naturalist
—Ascertaining the functions bird song requires information about when and where a song or, for males with multisong repertoires, songs are used. Because the need for and type of communication with mates and conspecifics changes with breeding stage and social context, detailed observations may reveal differential use of song or of different song types. Our objective was to examine the use, and d...
متن کاملThe American Midland Naturalist
—We sampled fishes and aquatic insects monthly ( Jun.–Sept. 2002) from intermittent tributaries of the Alum Fork of the Saline River (Arkansas, U.S.A.) to quantify the response of fish and aquatic insect assemblage properties to seasonal desiccation and habitat fragmentation. We collected a total of 4219 individuals, representing 18 species of fishes and 27 families of aquatic insects. Changes ...
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