Carbon Isotopic Composition of Tree Rings as A Tool for Biomonitoring CO2 Level

Response of the nitrogen isotopic composition of tree-rings following tree-clearing and land-use change.

Clear-cutting of forests affects the nitrogen cycle and the nitrogen isotopic composition of bioavailable ammonium and nitrate in the soil. Here, we have used nitrogen isotopic variations of tree-rings in red oak (Quercus rubra) and white oak (Quercus alba) as indicators of changes in the nitrogen cycle on a local scale. The delta15N values of late-wood from trees at two remnant forest stands i...

Carbon isotopic composition of individual Precambrian microfossils.

Ion microprobe measurements of carbon isotope ratios were made in 30 specimens representing six fossil genera of microorganisms petrified in stromatolitic chert from the approximately 850 Ma Bitter Springs Formation, Australia, and the approximately 2100 Ma Gunflint Formation, Canada. The delta 13C(PDB) values from individual microfossils of the Bitter Springs Formation ranged from -21.3 +/- 1....

Tracing carbon uptake from a natural CO2 spring into tree rings: an isotope approach.

We analyzed 14C, 13C and 18O isotope variations over a 50-year period in tree rings of Quercus ilex L. trees growing at a natural CO2 spring in a Mediterranean ecosystem. We compared trees from two sites, one with high and one with low exposure to CO2 from the spring. The spring CO2 is free of 14C. Thus, this carbon can be traced in the wood, and the amount originating from the spring calculate...

Interpreting the Carbon Isotopic Composition of Ureilites

Ureilites and carbonaceous chondrites: The origin of ureilite meteorites has been consistently regarded as problematic [1]. A distinctive feature of ureilites is that they contain carbonaceous matter up to 6 wt. %, particularly in the form of graphite in veinlets between silicate (mostly olivine) crystals, and along their cleavage planes. The carbonaceous matter within them suggests a relations...

Meiofauna as a Tool for Marine Ecosystem Biomonitoring