期刊
BIOGEOSCIENCES
卷 11, 期 16, 页码 4477-4491出版社
COPERNICUS GESELLSCHAFT MBH
DOI: 10.5194/bg-11-4477-2014
关键词
-
资金
- NSF [DEB-0919331, NSF-0630319]
- NASA [NASA-NNX09AI26G]
- Department of Energy [DE-FG02-08ER64599]
- NSF Division of Information and Intelligent Systems [NSF-1028291]
- Bonanza Creek Long-Term Ecological Research program - NSF the USDA Forest Service
- Division Of Environmental Biology
- Direct For Biological Sciences [1026415] Funding Source: National Science Foundation
- Division Of Environmental Biology
- Direct For Biological Sciences [1355081] Funding Source: National Science Foundation
- Div Of Information & Intelligent Systems
- Direct For Computer & Info Scie & Enginr [1028291] Funding Source: National Science Foundation
The large amount of soil carbon in boreal forest ecosystems has the potential to influence the climate system if released in large quantities in response to warming. Thus, there is a need to better understand and represent the environmental sensitivity of soil carbon decomposition. Most soil carbon decomposition models rely on empirical relationships omitting key biogeochemical mechanisms and their response to climate change is highly uncertain. In this study, we developed a multi-layer microbial explicit soil decomposition model framework for boreal forest ecosystems. A thorough sensitivity analysis was conducted to identify dominating biogeochemical processes and to highlight structural limitations. Our results indicate that substrate availability (limited by soil water diffusion and substrate quality) is likely to be a major constraint on soil decomposition in the fibrous horizon (40-60% of soil organic carbon (SOC) pool size variation), while energy limited microbial activity in the amorphous horizon exerts a predominant control on soil decomposition (> 70% of SOC pool size variation). Elevated temperature alleviated the energy constraint of microbial activity most notably in amorphous soils, whereas moisture only exhibited a marginal effect on dissolved substrate supply and microbial activity. Our study highlights the different decomposition properties and underlying mechanisms of soil dynamics between fibrous and amorphous soil horizons. Soil decomposition models should consider explicitly representing different boreal soil horizons and soil-microbial interactions to better characterize biogeochemical processes in boreal forest ecosystems. A more comprehensive representation of critical biogeochemical mechanisms of soil moisture effects may be required to improve the performance of the soil model we analyzed in this study.
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