Argonne Terrestrial Ecosystem Science SFA Research sponsored by the DOE Office of Biological and Environmental Research

  • We need your help to map soil organic matter quality across the permafrost-region

    Contribute to a spectroscopy database: 1. send us your samples, 2. we'll give you spectra, and 3. in return, let us add your spectra to the database. More »

    Sample graph

  • Studying the heterogeneity of soil organic carbon in the permafrost-region

    Through intensive sampling (trenching and coring) across flat-, low-, and high-centered ice-wedge polygons, we are investigating the appropriate scale for generalizing the heterogeneity of soil carbon stocks and reducing the uncertainty in regional estimates.

    Photos of activities related to soil sampling

  • Cryogenic processes contribute to the formation and characteristics of permafrost-region soils

    Cryoturbation of organic matter leads to deep burial of high carbon stocks in permafrost-region soils. Cryoturbated organic matter is highlighted in yellow.

    Photo of permafrost-region soil with cryoturbated organic matter highlighted

  • Soil data inform process-based models

    Explicit modeling of oxygen transport in soil pore-water systems improves model simulations of greenhouse gas emissions from peatlands. More »

    Sample graphs

  • Evaluating the intrinsic lability of permafrost-region soils

    Laboratory incubations are being used to assess the decomposability of organic matter stored in permafrost-region soils. These data will help to identify and calibrate biogeochemical indicators of decomposability derived from infrared spectroscopy.

    Photos of equipment related to measurement of carbon dioxide and methane production

  • Geospatial modeling and analysis are used to produce high-resolution maps of soil organic carbon

    Mapping the quantity and quality of soil organic carbon stored in permafrost-region soils will serve as benchmarks for Earth-system and regional-scale models.

    Sample geospatial modeling and analysis data

Soil Carbon Response to Environmental Change

One of the greatest environmental challenges of the 21st century lies in predicting the impacts of climatic change and other environmental perturbations on Earth's biogeochemical cycles. Soil is a significant component of global biogeochemical cycles because it contains two-thirds of the world's terrestrial carbon (C) stocks and serves as the reservoir for nutrients that support ecosystem productivity.

Although soil organic C stocks were built over thousands of years, these C stores can be susceptible to far more rapid release back to the atmosphere. There are clear regional and local differences in how soils function and in the amount, distribution, and stability of soil organic C stocks. These differences must be accounted for to predict the responses of soils and their C stocks to environmental change and subsequent C feedbacks to the atmosphere.

The Argonne TES SFA conducts fundamental research to quantify and characterize the C stored in soils and evaluate its potential responses to environmental change. Our research

  • focuses on regions that are critically sensitive to environmental forcing factors or for which modeling uncertainties are high and
  • addresses region-specific factors and processes controlling soil C distributions, their potential responses to environmental forcing, and key knowledge gaps.
Figure 1. Inconsistencies between circumpolar estimates of soil organic C (SOC) stocks (to 1 m depth) derived from observations (Northern Circumpolar Soil Carbon Database; www.bbcc.su.se/data/ncscd/) and baseline Earth system model simulations (calculated from the mean values of four CMIP5 models: BCC-CSM1.1, CanESM2, MIROC-ESM, and GFDL-ESM2M). From Mishra et al., 2013, Environ. Res. Lett. 8:035020 (doi:10.1088/1748-9326/8/3/035020).
Figure 1. Inconsistencies between circumpolar estimates of soil organic C (SOC) stocks (to 1 m depth) derived from observations (Northern Circumpolar Soil Carbon Database; http://bolin.su.se/data/ncscd/) and baseline Earth system model simulations (calculated from the mean values of four CMIP5 models: BCC-CSM1.1, CanESM2, MIROC-ESM, and GFDL-ESM2M). From Mishra et al., 2013, Environ. Res. Lett. 8:035020 (doi:10.1088/1748-9326/8/3/035020).

At present, our SFA is focusing on soils of the northern circumpolar permafrost region, where huge organic C stocks are preserved mostly by the cold and often wet conditions. Climatic change is already causing widespread permafrost thawing and is likely to increase the decomposition rate of the region's soil C stocks. Return of this C to the atmosphere as the greenhouse gases, carbon dioxide and methane, could feed back to accelerate the rate of global warming. But current observation-based and model estimates of regional soil organic C stocks are both highly uncertain and not in agreement (Figure 1). Even less is known about the potential vulnerability of these C stocks to changing environmental conditions.

Our goal is to quantify the C currently preserved in permafrost-region soils, determine its spatial and vertical distributions, and assess how susceptible this C is to decomposition and release to the atmosphere. We have two major objectives:

  1. Provide reliable assessments of the spatial and vertical distributions of soil C stocks in permafrost regions. More »
  2. Develop empirical tools for predicting the potential decomposability of C stored in permafrost-region soils. More »