Results 211 to 220 of about 28,193 (230)
Some of the next articles are maybe not open access.
Incorporating indirect pathways in body size–trophic position relationships
Oecologia, 2020Body size, trophic position (TP), and trophic niche width are important elements of food webs; however, there is still debate regarding their interrelationships. Most studies have tested these correlations using datasets restricted to carnivores and bivariate models that disregard potential indirect effects of other factors, their interactions, and ...
Friedrich Wolfgang Keppeler +1 more
openaire +2 more sources
Trophic Structure, Effective Trophic Position, and Connectivity in Food Webs
The American Naturalist, 1975A new measure of distance from the food source to any member of a food web is introduced. This measure is referred to as effective tropic position. Effective trophic position is defined as a function of energy ingested per unit time by a population and the production of the autotrophs necessary to maintain that population. Trophic position thus defined
J. R. Kercher, H. H. Shugart,
openaire +1 more source
Trophic Consequences of a Positive Plant Interaction
The American Naturalist, 1996Positive interactions (mutualisms and commensalisms) are becoming more widely known as important processes in natural and agricultural communities. They can have strong and direct effects on associated species by creating hospitable environments for organisms lacking the morphological and/or physiological ability to cope without neighbors.
Sally D. Hacker, Mark D. Bertness
openaire +1 more source
Effective trophic positions in ecological acyclic networks
Ecological Modelling, 2006In the tropho-dynamic analysis of ecosystems the heuristic, discrete concept of trophic level has been replaced by the more realistic, continuous definition of trophic position. In ecological network analysis (ENA) the suite of matrix manipulations called canonical trophic aggregation (CTA) apportions each species’ feeding activity to a series of ...
Scotti, M. +4 more
openaire +2 more sources
Consumer trophic positions respond variably to seasonally fluctuating environments
Ecology, 2019AbstractThe effects of environmental seasonality on food web structure have been notoriously understudied in empirical ecology. Here, we focus on seasonal changes in one key attribute of a food web, consumer trophic position. We ask whether fishes inhabiting tropical river–floodplain ecosystems behave as seasonal omnivores, by shifting their trophic ...
Mcmeans, Bailey C. +10 more
openaire +3 more sources
Estuaries and Coasts, 2009
Stable isotope ratios of carbon and sulfur were used to assess organic matter utilization of numerically abundant consumers present in Apalachicola Bay, FL, USA. These results were used to infer nitrogen isotopic enrichment of organic matter sources in an effort to establish baseline δ15N enrichment for trophic evaluations.
Rachel Marie Wilson +3 more
openaire +1 more source
Stable isotope ratios of carbon and sulfur were used to assess organic matter utilization of numerically abundant consumers present in Apalachicola Bay, FL, USA. These results were used to infer nitrogen isotopic enrichment of organic matter sources in an effort to establish baseline δ15N enrichment for trophic evaluations.
Rachel Marie Wilson +3 more
openaire +1 more source
Nitrogen isotopes in otoliths reconstruct ancient trophic position
Environmental Biology of Fishes, 2010The ratio of 15 N/ 14 N( δ 15 N) from consumer and prey tissue is commonly used in ecological studies to determine trophic level, food web structure, and mean trophic level in aquatic ecosystems. There is a predictable positive relationship between the δ 15 N values in tissue and trophic level, caused by the bioaccumulation of 15 N in tissues of ...
Kirsten Rowell +2 more
openaire +1 more source
Limitations in Radiotracer Determination of Consumer Trophic Positions
Ecology, 1970Tropic transfer studies on wild radish (Raphanus raphanistrum) and ragweed (Ambrosia artemisiifolia) both indicated variations in the time of P32 uptake by herbivore species. This variation resulted from rapid temporal changes in plant organ availability with subsequent changes in consumer feeding patterns.
openaire +1 more source
Differences in trophic position among sympatric sea urchin species
Estuarine, Coastal and Shelf Science, 2006Abstract Three species of sea urchin regularly co-occur in high abundances on subtidal rocky reefs in south-western Australia. We used two lines of evidence (stable isotope analysis and gut contents analysis), to test whether these species occupy different trophic positions.
Mathew A. Vanderklift +2 more
openaire +1 more source