Interrogating trees for isotopic archives of atmospheric sulphur deposition and comparison to speleothem records.
Palaeorecords which depict changes in sulphur dynamics form an invaluable resource for recording atmospheric pollution. Tree rings constitute an archive that are ubiquitously available and can be absolutely dated, providing the potential to explore local- to regional-scale trends in sulphur availability. Rapid isotopic analysis by a novel "on-line" method using elemental analyser isotope ratio mass spectrometry (EA-IRMS) is developed, achieving sample precision of <0.4‰ using sample sizes of 40 mg wood powder. Tree cores from NE Italy show trends in pollution, evidenced through increasing concentrations of sulphur towards the youngest growth, and inverse trends in sulphur isotopes differentiating modern growth with light sulphur isotopes (+0.7‰) from pre-industrial growth (+7.5‰) influenced by bedrock composition. Comparison with speleothem records from the same location demonstrate replication, albeit offset in isotopic value due to groundwater storage. Using EA-IRMS, tree ring archives form a valuable resource for understanding local- to regional-scale sulphur pollution dynamics.
Lancaster Environment Centre, University of Lancaster, Lancaster LA1 4YQ, UK. Electronic address: p.wynn@lancaster.ac.uk.
P M
PM
Wynn
Department of Geography, Swansea University, Swansea SA2 8PP, UK.
N J
NJ
Loader
School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, Edgbaston, B15 2TT, UK.
I J
IJ
Fairchild
D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data; D001272:Atmosphere / Q000737:chemistry; D004784:Environmental Monitoring / Q000379:methods*; D007554:Isotopes; D007558:Italy; D013455:Sulfur / Q000032:analysis*; D013460:Sulfur Isotopes / Q000032:analysis; D014197:Trees / Q000737:chemistry*; D014934:Wood / Q000737:chemistry*
D000393:Air Pollutants; D007554:Isotopes; D013460:Sulfur Isotopes; D013455:Sulfur
Biogeochemistry; Isotopes; Pollution; Speleothems; Sulphur; Tree rings