본문 바로가기
HOME> 논문 > 논문 검색상세

논문 상세정보

Ecological Indicators v.75, 2017년, pp.234 - 241   SCIE SCOPUS
본 등재정보는 저널의 등재정보를 참고하여 보여주는 베타서비스로 정확한 논문의 등재여부는 등재기관에 확인하시기 바랍니다.

Are you what you eat? Effects of trophic discrimination factors on estimates of food assimilation and trophic position with a new estimation method

Bastos, Rodrigo F. (Programa de Pós Graduação em Biociências (Zoologia), Faculdade de Biociências − ); Corrêa, Fabiano (FABIO, Pontifícia Universidade Católica do Rio Grande do Sul − ); Winemiller, Kirk O. (PUCRS, Porto Alegre, RS, Brazil ); Garcia, Alexandre M. (Laboratório de Ictiologia, Instituto de Oceanografia − );
  • 초록  

    Abstract A key factor for estimates of assimilation of resources and trophic position based on stable isotope data is the trophic discrimination factor (TDF). TDFs are assumed based on literature reviews, but may vary depending on a variety of factors, including the type of diet. We analyzed effects of alternative TDFs on estimates of assimilated resources and trophic positions for an omnivorous fish, Jenynsia multidentata , that reveals dietary variation among locations across a salinity gradient of a coastal lagoon in southern Brazil. We also compared estimates of foods ingested vs. foods assimilated. Food assimilation was estimated using carbon ( δ 13 C) and nitrogen ( δ 15 N) stable isotope ratios of food sources and consumer muscle tissue and an isotopic mixing model (SIAR); consumer trophic position (TP) was estimated from consumer and production source δ 15 N values. Diet was estimated using an index of relative importance based on frequency of occurrence and volumetric and numeric proportions of food items from stomach contents. The effect of variation in TDF on food assimilation and TP was tested using three alternative TDFs reported in review papers. We then created a new method that used food source-specific TDFs (reported separately for herbivores and carnivores) weighted in proportion to estimated assimilation of resources according to mixing model estimates to estimate TP (hereafter TP WAR ). We found that plant material was not assimilated in a proportion similar to its importance in the diet of fish at a freshwater site, and the new method yielded best assimilation estimates. Animal material made greatest contributions to fish biomass irrespective of TDFs used in the mixing model. The new method produced TP estimates consistent with differences in estimated food assimilation along the salinity gradient. Our findings support the idea that food source-specific TDFs should be used in trophic studies of omnivores, since the method improved our ability to estimate trophic position and resource assimilation, two important ecological indicators. Highlights A new method to estimate trophic position of omnivores is proposed. The method is based on the differential trophic discrimination of each source. Mixing models results are used to construct the trophic discrimination factor. The new method reflected the differential assimilation of plant and animal sources.


  • 주제어

    Carnivory .   Diet shift .   Herbivory .   Isotopic fractionation .   Omnivory .   Trophic enrichment.  

 활용도 분석

  • 상세보기

    amChart 영역
  • 원문보기

    amChart 영역

원문보기

무료다운로드
  • 원문이 없습니다.

유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.

원문복사신청을 하시면, 일부 해외 인쇄학술지의 경우 외국학술지지원센터(FRIC)에서
무료 원문복사 서비스를 제공합니다.

NDSL에서는 해당 원문을 복사서비스하고 있습니다. 위의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.

이 논문과 함께 출판된 논문 + 더보기