Advantages of compound-specific stable isotope measurements over bulk measurements in studies on plant uptake of intact amino acids

2009 ◽  
Vol 23 (20) ◽  
pp. 3333-3342 ◽  
Author(s):  
Leopold Sauheitl ◽  
Bruno Glaser ◽  
Alexandra Weigelt
Keyword(s):  
Amino Acids ◽  
Stable Isotope ◽  
Plant Uptake ◽  
Isotope Measurements

scholarly journals Quantifying capital versus income breeding: New promise with stable isotope measurements of individual amino acids

2020 ◽  
Author(s):  
John P. Whiteman ◽  
Seth D. Newsome ◽  
Paco Bustamante ◽  
Yves Cherel ◽  
Keith A. Hobson
Keyword(s):  
Amino Acids ◽  
Stable Isotope ◽  
Income Breeding ◽  
Isotope Measurements

Manipulation experiments to infer the age and tracer composition of hydrologic fluxes

2020 ◽  
Author(s):  
Mitra Asadollahi ◽  
Paolo Benettin ◽  
Magali Nehemy ◽  
Andrea Rinaldo ◽  
Jeffrey McDonnell
Keyword(s):  
Stable Isotope ◽  
Boundary Conditions ◽  
Water Samples ◽  
Plant Uptake ◽  
Ground Truth ◽  
Root Water Uptake ◽  
Controlled Experiments ◽  
Soil Horizons ◽  
Isotope Measurements ◽  
Water Uptake Patterns

<p>Several ecohydrological problems such as when and where precipitation becomes the source of plant uptake are usually tackled through stable isotope measurements. Our ability to go after these questions is often limited by field conditions that cannot be controlled, but targeted manipulation experiments can go beyond some of these limitations by imposing known boundary conditions and allowing the experimental closure of the isotope balance. This contribution presents examples from existing experiments that aim to understand which water, in terms of age and tracer composition, is uptaken by vegetation or drained to deeper soil horizons. In particular, we illustrate the Spike II experiment, which was carried out on a large vegetated lysimeter within the EPFL campus (CH) in 2018. This experiment featured the application of 40 mm of isotopically-enriched water on top of the lysimeter and its tracking for 40 days through the soil water, the lysimeter bottom drainage and the plant xylem. A total of more than 900 water samples were collected to reconstruct the “story” of the labeled precipitation. The detailed results from such controlled experiments represent a fundamental “ground truth” for our understanding of root water uptake patterns in large and diverse landscapes.</p>

Hydrothermal Sr contamination of the Dippin sill, Isle of Arran, Western Scotland

1984 ◽  
Vol 48 (348) ◽  
pp. 311-322 ◽  
Author(s):  
A. P. Dickin ◽  
C. M. B. Henderson ◽  
F. G. F. Gibb
Keyword(s):  
Stable Isotope ◽  
Hydrothermal Alteration ◽  
Closed System ◽  
Hydrothermal Systems ◽  
Hydrothermal Fluids ◽  
Drill Core ◽  
Sr Isotope ◽  
Core Section ◽  
High Silica ◽  
Isotope Measurements

Abstract The Dippin sill, which is emplaced into the Triassic sediments of SE Arran, is an alkaline basic sheet which displays pronounced hydrothermal alteration. The 40-m-thick sill has suffered pervasive contamination with radiogenic Sr, introduced from the Triassic sediments by hydrothermal fluids. Stable isotope measurements suggest that fluids were of meteoric origin, but were restricted to a small closed-system circulation. Initial 87Sr/86Sr ratios in the sill were raised from an original value of 0.7032 to a maximum of 0.7091, contamination being especially pronounced near the contacts at Dippin Head itself (localities 12 and 14) and in a drill core section through the sill above Dippin. Hydrothermal Sr was incorporated into an early-formed high-CaO, high-Sr analcime, which replaced unstable high-silica nepheline in interstitial patches. However, this high-CaO analcime, along with plagioclase, was later replaced by a low-CaO, low-Sr analcime, allowing Sr leaching from the margins of the sill. Hydrothermal fluids are thought to have migrated up to 1 km laterally, up the dip of the sill, mainly via tension joints forming in the cooling intrusion. Pooling of hot fluids at the upper end of the sill probably raised water/rock ratios in this region and allowed greater Sr contamination during mineralogical alteration. The undersaturated mineralogy of the sill accounts for its pervasive hydrothermal Sr contamination, which contrasts markedly with the relatively undisturbed Sr isotope compositions of Hebridean granites involved in hydrothermal systems.

scholarly journals Intercellular Transfer of Proteins as Identified by Stable Isotope Labeling of Amino Acids in Cell Culture

2009 ◽  
Vol 285 (9) ◽  
pp. 6285-6297 ◽  
Author(s):  
Ming Li ◽  
Jason M. Aliotta ◽  
John M. Asara ◽  
Qian Wu ◽  
Mark S. Dooner ◽  
...  
Keyword(s):  
Amino Acids ◽  
Cell Culture ◽  
Stable Isotope ◽  
Isotope Labeling ◽  
Stable Isotope Labeling ◽  
Intercellular Transfer

Stable isotope measurements and modeling to verify the authenticity of dairy products

2017 ◽  
pp. 239-256
Author(s):  
Emad Ehtesham ◽  
Federica Camin ◽  
Luana Bontempo ◽  
Russell D. Frew
Keyword(s):  
Stable Isotope ◽  
Dairy Products ◽  
Isotope Measurements
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