PT - JOURNAL ARTICLE AU - Weixin Zhang AU - Yuanqi Chen AU - Leilei Shi AU - Xiaoli Wang AU - Yongwen Liu AU - Xingquan Rao AU - Yongbiao Lin AU - Yuanhu Shao AU - Xiaobo Li AU - Shengjie Liu AU - Shilong Piao AU - Weixing Zhu AU - Xiaoming Zou AU - Shenglei Fu TI - Faster carbon accumulation in global forest soils AID - 10.1101/149393 DP - 2017 Jan 01 TA - bioRxiv PG - 149393 4099 - http://biorxiv.org/content/early/2017/06/13/149393.short 4100 - http://biorxiv.org/content/early/2017/06/13/149393.full AB - Comparing soil organic carbon (SOC) stocks across space and time is a fundamental issue in global ecology. However, the conventional approach fails to determine SOC stock in an equivalent volume of mineral-soil, and therefore, SOC stock changes can be under- or overestimates if soils swell or shrink during forest development or degradation. Here, we propose to estimate SOC stock as the product of mineral-soil mass in an equivalent mineral-soil volume and SOC concentration expressed as g C Kg-1 mineral-soil. This method enables researchers to compare SOC stocks across space and time. Our results show an unaccounted SOC accumulation of 2.4 - 10.1 g C m-2 year-1 in the 1m surface mineral-soils in global forests. This unaccounted SOC amounts to an additional C sink of 0.12 – 0.25 Pg C year-1, which equals 30 – 62% of the previously estimated annual SOC accumulation in global forests. This finding suggests that forest soils are stronger C sinks than previously recognized.