This study examines stable isotope ratios of carbon and nitrogen in bone collagen and the elemental concentrations of strontium in the bone mineral of terrestrial vertebrates fi'om a variety of ecosystems. Documentation of the separation oftrophic levels by these indices is essential for the assessment of the trophic position of prehistoric humans. Particular emphasis is given to carnivores in ...

Interpretation of nematode community indices requires a reference to a relatively undisturbed community. Maturity and trophic diversity index values were compared for five pairs of certified organically and conventionally managed soils in the Piedmont region of North Carolina. Available nitrogen (nitrate, ammonium) was estimated at various lag periods relative to times of sampling for nematode ...

Comparative analysis of trophic networks was carried out to evaluate environmental management actions aimed at countering an environmental crisis in Orbetello Lagoon, Italy. Two mass-balance models of this shallow water coastal system were constructed, for 1995 and 1996. During this period, there was an observed change in the composition of the submerged vegetation that indicated a significant ...

Using recent indices developed, in part, for use under the European Water Framework Directive (AMBI, BENTIX, BOPA, BQI, I2EC and the trophic index ITI), the ecological quality status of two highly contaminated environments--the Bay of Seine and the Seine estuary (Eastern English Channel)--was determined on several spatial and temporal scales. Data from 604 observations gathered over a 14-year p...

The feeding habits and trophic level of Himantura gerrardi were studied according to sex and size classes utilizing 80 individuals obtained using bottom trawl between May and December 2014 from Oman Sea. Collected specimens were divided in three size classes (small 58 cm) based on disk width (DW). Preys were identified in seven main zoological categories, where crustacean and polychaetes were t...

the parameters used to determine the trophic state of a water body are: total phosphorus (tp),transparency (secchi disk depth) and chlorophyll a. however, these parameters show strong seasonalfluctuations which may hinder the estimation of trophic state. some authors have proposed that sediments be used as an additional tool to evaluate the trophic state of a water body. the aim of this study w...