期刊
GLOBAL CHANGE BIOLOGY
卷 15, 期 9, 页码 2295-2310出版社
WILEY
DOI: 10.1111/j.1365-2486.2009.01903.x
关键词
carbon quality; Q(10); radiocarbon; SOC decomposition; SOC fractionation; stable C; temperate forests
资金
- Northern, Southern and Pacific Southwest Research Stations of USDA Forest Service
We investigated mean residence time (MRT) for soil organic carbon (SOC) sampled from paired hardwood and pine forests located along a 22 degrees C mean annual temperature (MAT) gradient in North America. We used acid hydrolysis fractionation, radiocarbon analyses, long-term laboratory incubations (525-d), and a three-pool model to describe the size and kinetics of the acid insoluble C (AIC), active and slow SOC fractions in soil. We found that active SOC was 2 +/- 0.2% (mean +/- SE) of total SOC, with an MRT of 33 +/- 6 days that decreased strongly with increasing MAT. In contrast, MRT for slow SOC and AIC (70 +/- 6% and 27 +/- 6% of total SOC, respectively) ranged from decades to thousands of years, and neither was significantly related to MAT. The accumulation of AIC (as a percent of total SOC) was greater in hardwood than pine stands (36% and 21%, respectively) although the MRT for AIC was longer in pine stands. Based on these results, we suggest that the responsiveness of most SOC decomposition in upland forests to global warming will be less than currently modeled, but any shifts in vegetation from hardwood to pine may alter the size and MRT of SOC fractions.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据