AI Article Synopsis
- The study investigates sulfur isotopic ratios (sigma 34S) in tree rings, which are often too low for traditional analysis methods.
- The researchers measured sigma 34S values in both water-soluble and organically bound sulfur in coniferous tree rings from Japan using advanced techniques.
- The findings indicate that the sigma 34S values in tree rings reflect past atmospheric sulfur sources, suggesting they can serve as a valuable tool for understanding historical sulfur pollution levels.
Article Abstract
Little is understood about the usefulness of sulfur isotopic ratios (sigma 34S) in tree rings because the sulfur content in rings is generally insufficient for analysis using conventional methods. We present sigma 34S values of the water-soluble and the organically bound sulfur fractions in rings of coniferous trees grown in Japan, analyzed using a large-volume oxygen bomb. Comparing the sigma 34S values of the organically bound fraction in tree rings with past atmospheric sulfur concentrations and with those of their sources, we find clear evidence that the sigma 34S values of the organically bound fraction in the rings are dependent upon the values of the atmospheric sulfur sources. The evidence suggests that the sigma 34S values in tree rings are a useful chronological proxy for evaluating possible causes of past atmospheric sulfur pollution.
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| http://dx.doi.org/10.1021/es060321w | DOI Listing |
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Article Synopsis
- The study investigates sulfur isotopic ratios (sigma 34S) in tree rings, which are often too low for traditional analysis methods.
- The researchers measured sigma 34S values in both water-soluble and organically bound sulfur in coniferous tree rings from Japan using advanced techniques.
- The findings indicate that the sigma 34S values in tree rings reflect past atmospheric sulfur sources, suggesting they can serve as a valuable tool for understanding historical sulfur pollution levels.
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