Looking beyond the trees for carbon storage.

About one-third of the carbon dioxide (CO2) emitted by human activities is absorbed by terrestrial ecosystems. These carbon sinks, along with the oceans, slow the buildup of atmospheric CO2 and the pace of global warming. The locations where the absorbed emissions are stored govern the long-term stability and management of carbon pools—those places in Earth's biosphere that can accumulate, store, and release carbon. Nonetheless, how carbon is dispersed across different pools on land remains unclear. On page 1291 of this issue, Bar-On et al. (1) report an unexpectedly large distribution of terrestrial carbon in pools of nonliving organic matter that are natural or human made. Carbon sequestration beyond the more vulnerable components, such as trees, could imply greater carbon stability on land than previously thought. This finding highlights the growing complexity of the future evolution and management of carbon sinks and reservoirs. [ABSTRACT FROM AUTHOR]