Аннотация:Energy utilization by benthic invertebrates from several New Zealand streams was investigated using stable carbon isotope analysis. 13C/12C ratios indicated that the faunas of small, forested streams depended primarily on allochthonous sources of carbon whereas variable utilization of allochthonous and autochthonous materials was shown by species from a grassland stream. Relatively '3C-depleted values obtained for the mayfly, Deleatidium from forested sites suggest that its larvae assimilate algae selectively. A shift to greater dependence on autochthonous energy sources was shown by invertebrates from small, recently clearcut catchments (1-4 yr) in response to canopy removal and flushing of forest-derived organic materials from the streams. Although coarse in its resolving power, stable carbon isotope methodology provides insights into the trophic linkages within a community and has potential as a management tool.
