Data from: Dynamics of deep soil carbon - insights from 14C time series across a climatic gradient

Quantitative constraints on soil organic matter (SOM) dynamics are
essential for comprehensive understanding of the terrestrial carbon cycle.
Deep soil carbon is of particular interest, as it represents large stocks
and its turnover times remain highly uncertain. In this study, SOM
dynamics in both the top and deep soil across a climatic (average
temperature ~1-9 °C) gradient are determined using time-series (~20 years)
14C data from bulk soil and water-extractable organic carbon (WEOC).
Analytical measurements reveal enrichment of bomb-derived radiocarbon in
the deep soil layers on the bulk level during the last two decades. The
WEOC pool is strongly enriched in bomb-derived carbon, indicating that it
is a dynamic pool. Turnover time estimates of both the bulk and WEOC pool
show that the latter cycles up to a magnitude faster than the former. The
presence of bomb-derived carbon in the deep soil, as well as the rapidly
turning WEOC pool across the climatic gradient implies that there likely
is a dynamic component of carbon in the deep soil. Precipitation and
bedrock type appear to exert a stronger influence on soil C turnover time
and stocks as compared to temperature.