نتایج جستجو برای: carbon isotope discrimination delta
تعداد نتایج: 423589 فیلتر نتایج به سال:
We examined 6I3C and 6 " ~ in needle (current and 1-year-old) and soil samples collected on two occasions (July and September 1999) from a 15-year-old loblolly pine (Pinus taeda L.) stand in an irrigation and fertilization experiment to investigate whether these treatments leave specific isotope signals in the samples and thus to infer the effects of treatments on C and N cycling. Irrespective ...
The Florida manatee (Trichechus manatus latirostris) is a herbivorous marine mammal that occupies freshwater, estuarine and marine habitats. Despite being considered endangered, relatively little is known about its feeding ecology. The present study expands on previous work on manatee feeding ecology by providing critical baseline parameters for accurate isotopic data interpretation. Stable car...
Abstract Understanding carbon incorporation rates and diet-to-tissue discrimination (Δ(13)C(tissue-diet)) in animals is necessary to interpret stable isotope data collected from animals in the field. Our current understanding of the carbon dynamics in terrestrial ectotherms such as snakes, lizards, and turtles is poorly developed. Here we use a diet switch experiment to estimate carbon incorpor...
About 0.3 g of freeze-dried and powdered sediment sample was decalcified using HCl. Subsequently Total Organic Carbon (TOC) and δ 13 Corg concentrations were measured using a Fisons Instruments CNS NA 1500 analyzer coupled to a Thermo Delta Plus isotope ratio spectrometer. Results were normalized to international standards. Average analytical uncertainty based on duplicate analyses of sediment ...
Abstract Stable hydrogen, carbon, nitrogen, oxygen and sulfur (HCNOS) isotope compositions expressed as isotope-delta values are typically reported relative to international standards such Vienna Standard Mean Ocean Water (VSMOW), Peedee belemnite (VPDB) or Cañon Diablo Troilite (VCDT). These chosen by convention the calibration methods used realise them in practice undergo occasional changes. ...
The carbon isotope ratios (delta(13)C) of 160 beers from around the world ranged from -27.3 to -14.9 per thousand, primarily due to variation in the percentage of C(3) or C(4) plant carbon in the final product. Thirty-one percent of beers had a carbon signature of C(3) plants (barley, rice, etc.), whereas the remaining 69% contained some C(3)-C(4) mixture (mean of mixtures, 39 +/- 11% C(4) carb...
[1] Photosynthesis and respiration impart distinct isotopic signatures to the atmosphere that are used to constrain global carbon source/sink estimates and partition ecosystem fluxes. Increasingly, the ‘‘Keeling plot’’ method is being used to determine the carbon isotope composition of ecosystem respiration (dCR) in order to better understand the processes controlling ecosystem isotope discrimi...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید