Δ14C level of annual plants and fossil fuel derived CO2 distribution across different regions of China

Abstract The 14 C level in annual plants is a sensitive tracer for monitoring fossil fuel derived CO 2 in the atmosphere. Corn leave samples were selected from different regions of China, including high mountains in the Tibetan Plateau, grassland in Inner Mongolia, and inland and coastal cities during the summer of 2010. The 14 C/ 12 C ratio of the samples was measured with the NEC compact AMS system at the Institute of Heavy Ion Physics, Peking University. The fossil fuel derived CO 2 was estimated by comparing the measured Δ 14 C values of corn leave samples to background atmospheric Δ 14 C level. The influences of topography, meteorological conditions and carbon cycling processes on the fossil fuel derived CO 2 concentration are considered when interpreting the data. Our results show a clear association of the low Δ 14 C values with regions where human activities are intensive.