期刊
RADIOCARBON
卷 63, 期 4, 页码 1303-1319出版社
UNIV ARIZONA DEPT GEOSCIENCES
DOI: 10.1017/RDC.2021.42
关键词
carbon; mineral soil; molecular sieve; soil respiration
资金
- U.S. NSF OPP [1649664, 1650084]
- Directorate For Geosciences [1649664] Funding Source: National Science Foundation
- Directorate For Geosciences
- Office of Polar Programs (OPP) [1650084] Funding Source: National Science Foundation
- Office of Polar Programs (OPP) [1649664] Funding Source: National Science Foundation
A passive sampler was developed for time-integrated collection and radiocarbon (C-14) analysis of soil respiration. It allows for more continuous investigations of soil C emission sources, particularly suitable for Arctic environments.
We developed a passive sampler for time-integrated collection and radiocarbon (C-14) analysis of soil respiration, a major flux in the global C cycle. It consists of a permanent access well that controls the CO2 uptake rate and an exchangeable molecular sieve CO2 trap. We tested how access well dimensions and environmental conditions affect collected CO2, and optimized cleaning procedures to minimize (CO2)-C-14 memory. We also deployed two generations of the sampler in Arctic tundra for up to two years, collecting CO2 over periods of 3 days-2 months, while monitoring soil temperature, volumetric water content, and CO2 concentration. The sampler collects CO2 at a rate proportional to the length of a silicone tubing inlet (7-26 mu g CO2-C day(-1).m Si-1). With constant sampler dimensions in the field, CO2 recovery is best explained by soil temperature. We retrieved 0.1-5.3 mg C from the 1st and 0.6-13 mg C from the 2nd generation samplers, equivalent to uptake rates of 2-215 (n=17) and 10-247 mu g CO2-C day(-1) (n=20), respectively. The method blank is 8 +/- 6 mu g C (mean +/- sd, n=8), with a radiocarbon content (fraction modern) ranging from 0.5875-0.6013 (n=2). The sampler enables more continuous investigations of soil C emission sources and is suitable for Arctic environments.
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