Prediction of atmospheric δ13CO2 using fossil plant tissues Export

@article{citeulike:6099482, abstract = {Reconstruction of the carbon isotope composition of atmospheric CO2 is critical to the understanding of long-term global carbon cycling. We have suggested that the δ 13C value of land plant carbon (δ 13C p ) preserved in the geologic record should reflect the δ 13CO2 at the time during which the plants grew (δ 13C a ), based on a meta-analysis of modern plant data. Here we present the results of laboratory experiments designed to quantify the relationship between plant tissue δ 13C and δ 13CO2 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 δ 13C a (≈24‰) and pCO2 (≈740 ppmv) we observed a consistent correlation between δ 13C a and δ 13C p (p < 0.001). We show an average isotopic depletion of −25.4‰ for aboveground tissue and −23.2‰ for belowground tissue of Raphanus sativus L. relative to the composition of the atmosphere under which it formed. For aboveground and belowground tissue, grown at both ∼23°C and ∼29°C, correlation was strong and significant (r 2 ≥ 0.98 and p < 0.001); variation in pCO2 level had little or no effect on this relationship. These results validate our initial conclusion that in the absence of environmental stress, plant δ 13C primarily reflects atmospheric δ 13CO2 linearly across pCO2 levels; the demonstrated excellent correlation in δ 13C a and δ 13C p suggests a high level of predictive power across varying environmental conditions. }, author = {Jahren, A. Hope and Arens, Nan C. and Harbeson, Stephanie A.}, citeulike-article-id = {6099482}, citeulike-linkout-0 = {http://www.agu.org/pubs/crossref/2008/2006RG000219.shtml}, citeulike-linkout-1 = {http://dx.doi.org/10.1029/2006RG000219}, day = {11}, doi = {10.1029/2006RG000219}, issn = {8755-1209}, journal = {Reviews of Geophysics}, keywords = {carbon, climate, co2, correlation, fossil, isotope, paleoclimate, proxy, vegetation}, month = {January}, number = {1}, pages = {RG1002+}, posted-at = {2009-11-11 20:56:30}, priority = {2}, title = {Prediction of atmospheric δ13CO2 using fossil plant tissues}, url = {http://dx.doi.org/10.1029/2006RG000219}, volume = {46}, year = {2008} }

TY - JOUR ID - citeulike:6099482 L3 - citeulike-article-id:6099482 N2 - Reconstruction of the carbon isotope composition of atmospheric CO2 is critical to the understanding of long-term global carbon cycling. We have suggested that the δ 13C value of land plant carbon (δ 13C p ) preserved in the geologic record should reflect the δ 13CO2 at the time during which the plants grew (δ 13C a ), based on a meta-analysis of modern plant data. Here we present the results of laboratory experiments designed to quantify the relationship between plant tissue δ 13C and δ 13CO2 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 δ 13C a (≈24‰) and pCO2 (≈740 ppmv) we observed a consistent correlation between δ 13C a and δ 13C p (p < 0.001). We show an average isotopic depletion of −25.4‰ for aboveground tissue and −23.2‰ for belowground tissue of Raphanus sativus L. relative to the composition of the atmosphere under which it formed. For aboveground and belowground tissue, grown at both ∼23°C and ∼29°C, correlation was strong and significant (r 2 ≥ 0.98 and p < 0.001); variation in pCO2 level had little or no effect on this relationship. These results validate our initial conclusion that in the absence of environmental stress, plant δ 13C primarily reflects atmospheric δ 13CO2 linearly across pCO2 levels; the demonstrated excellent correlation in δ 13C a and δ 13C p suggests a high level of predictive power across varying environmental conditions. IS - 1 JF - Reviews of Geophysics SN - 8755-1209 TI - Prediction of atmospheric δ13CO2 using fossil plant tissues VL - 46 SP - RG1002 KW - carbon KW - climate KW - co2 KW - correlation KW - fossil KW - isotope KW - paleoclimate KW - proxy KW - vegetation AU - Jahren, Hope AU - Arens, Nan AU - Harbeson, Stephanie PY - 2008/01/11/ UR - http://dx.doi.org/10.1029/2006RG000219 ER -