A comparison of radiocarbon ages derived from bulk peat and selected plant macrofossils in basal peat cores from circum-arctic peatlands

摘要: Abstract Databases of basal radiocarbon (14C) ages from peatlands have been used extensively at regional and global scales to examine peatland initiation, land-cover change carbon cycle dynamics. Many dates collected analyzed before the 1990s are bulk peat samples organic-rich sediments, such might either too young or old due inclusion non-contemporary via translocation higher horizons. However, there is rarely a systematic assessment this problem, especially for large datasets. Here we AMS 14C dating both individual macrofossils same horizon each 40 cores across North America Siberia evaluate differences between two sample types. Our results show that no significant difference derived material plant macrofossils. We find greatest age overlap 2σ calibrated distributions occurred aboveground as moss fragments, seeds, herbaceous leaves, suggesting contemporaneous with biomass active uptake. Dates including wood fragments showed wider divergence compared leaves. evidence statistically consistent bias introduced by peat.