Yang Wang

TL;DR: It is proposed that the global expansion of C4 biomass may be related to lower atmospheric carbon dioxide levels because C4 photosynthesis is favoured over C3 photosynthesis when there are low concentrations of carbon dioxide in the atmosphere.

TL;DR: In this article, the relationship between the carbon isotopic composition of modern soil carbonate and coexisting organic matter was investigated and it was shown that the two systematically differ by 14-16% in undisturbed modern soils.

TL;DR: In this article, structural carbonate in biogenic apatite in the postmortem environment is modeled as a process of watermineral interaction, and closed-and open-system model calculations suggest that δ 13 C is much more resistant to diagenetic modification than δ 18 O. Application of the model to teeth, and carbonate cement in sediments from the Badlands, South Dakota, illustrates that these values represent varying extents of diagenesis.

TL;DR: The isotopic composition of soil CO 2 has been investigated for the past three decades by earth scientists in a variety of disciplines as discussed by the authors, and it is recognized that most soils are at quasi-steady state, and that the C isotope composition of respired CO 2 is the same as that of the biological sources in the soil.

TL;DR: In this paper, a relationship between speleothem stable isotopes (δ 13 C δ 18 O) and in situ cave forcing mechanisms is found. But the relationship between calcite and cave air ventilation was not investigated.