Prediction of atmospheric δ13CO2 using fossil plant tissues

[摘要] To summarize the content: we presented the results of laboratory experiments designed to quantify the relationship between plant tissue δ¹³C and δ¹³CO₂ values under varying environmental conditions, including differential pCO₂ ranging from 1 to 3 times today’s levels. As predicted, plants grown under elevated pCO2 showed increased average biomass compared to controls grown at the same temperature. Across a very large range in δ¹³Ca (≈ 24 ‰) and pCO₂ (≈ 740 ppmv) we observed a consistent correlation between δ13Ca and δ¹³Cp (p<0.001). We show an average isotopic depletion of -25.4 ‰ for above-ground tissue and -23.2 ‰ for below-ground tissue of Raphanus sativus L. relative to the composition of the atmosphere under which it formed. For both above- and below-ground tissue, grown at both ~23 °C and ~29 °C, correlation was strong and significant (r2 ≥ 0.98, p<0.001); variation in pCO₂ level had little or no effect on this relationship.

[发布日期] 2008-06-30

[学科分类] 地球科学(综合)

[关键词] BIOMASS;FORECASTING;GEOPHYSICS;PLANT TISSUES isotope;carbon