Mercury is a pervasive environmental contaminant, the anthropogenic portion of which is increasing globally, and in northeastern North America in particular. Seabirds frequently are used as indicators of the marine environment, including mercury contamination. We analysed paired samples for total mercury (Hg) concentrations in feathers and blood from adult and chick, albumen, and lipid-free yol...

[1] Previous work suggests that the relationship between the carbon isotope composition of air (dCa) and plant leaf tissue (dCp) can be used to track changes in the carbon isotope composition of paleo-atmospheric CO2. Here we test this assertion in a series of experiments using the model plant Arabidopsis thaliana grown under a range of atmospheric CO2 concentrations relevant to geologic time (...

In this study, stable carbon isotope ratios in the glucose samples were extracted from annual pine tree rings as bio-indicators of contemporary environmental changes in heavily urbanized areas. The sampling sites were located in close proximity to point source pollution emitters, such as a heat and power plant "Łaziska" and steelworks "Huta Katowice" in Silesia (Poland). The analysed samples co...

Stable carbon isotope measurements of the organic matter associated with the carbonate globules and the bulk matrix material in the ALH84001 Martian meteorite indicate that two distinct sources are present in the sample. The delta 13C values for the organic matter associated with the carbonate globules averaged -26% and is attributed to terrestrial contamination. In contrast, the delta 13C valu...

Seasonal and inter-annual dynamics of growth, non-structural carbohydrates (NSC) and carbon isotope composition (δ(13)C) of NSC were studied in a beech forest of Central Italy over a 2-year period characterized by different environmental conditions. The net C assimilated by forest trees was mainly used to sustain growth early in the season and to accumulate storage carbohydrates in trunk and ro...

The ratio of l*C : 13C was measured for Emiliania huxleyi cells grown under a range of irradiances in batch culture. Based on the assumption that HCO, was the carbon source, the maximum discrimination against 13C in the decalcified E. huxleyi cells was 24.6?& at 4.8 mol photons m-* d-l and the minimum discrimination was 17.9?& at 0.5 mol photons m-* d-l. In calcified cells, the range of 13C iso...

Negative carbon isotope excursions measured in marine and terrestrial substrates indicate large-scale changes in the global carbon cycle, yet terrestrial substrates characteristically record a larger-amplitude carbon isotope excursion than marine substrates for a single event. Here we reconcile this difference by accounting for the fundamental increase in carbon isotope fractionation by land pl...

tolerant cultivars showing less growth reduction than sensitive cultivars under saline conditions (Qian et al., We evaluated leaf C isotope discrimination as affected by salinity 2001; Suplick-Ploense et al., 2002). Growth reduction among three Kentucky bluegrass (Poa pratensis L.) cultivars that differ in their salt tolerance. ‘Moonlight’, ‘NorthStar’, and ‘P-105’ under salt stress could be at...

Heliconius and Laparus butterflies exhibit a unique pollen-collecting behaviour that enhances lifespan and fecundity. The specific nutritional contribution of pollen, however, had not been previously demonstrated. We used stable isotope variation to trace the carbon flow into eggs from corn pollen provided experimentally to ovipositing female Heliconius charitonia, and to evaluate the use of is...