TY - JOUR
T1 - Below-ground process responses to elevated CO2 and temperature
T2 - A discussion of observations, measurement methods, and models
AU - Pendall, Elise
AU - Bridgham, Scott
AU - Hanson, Paul J.
AU - Hungate, Bruce
AU - Kicklighter, David W.
AU - Johnson, Dale W.
AU - Law, Beverly E.
AU - Luo, Yiqi
AU - Megonigal, J. Patrick
AU - Olsrud, Maria
AU - Ryan, Michael G.
AU - Wan, Shiqiang
PY - 2004/5
Y1 - 2004/5
N2 - Rising atmospheric CO2 and temperatures are probably altering ecosystem carbon cycling, causing both positive and negative feedbacks to climate. Below-ground processes play a key role in the global carbon (C) cycle because they regulate storage of large quantities of C, and are potentially very sensitive to direct and indirect effects of elevated CO2 and temperature. Soil organic matter pools, roots and associated rhizosphere organisms all have distinct responses to environmental change drivers, although availability of C substrates will regulate all the responses. Elevated CO 2 increases C supply below-ground, whereas warming is likely to increase respiration and decomposition rates, leading to speculation that these effects will moderate one another. However, indirect effects on soil moisture availability and nutrient supply may alter processes in unexpected directions. Detailed, mechanistic understanding and modelling of below-ground flux components, pool sizes and turnover rates is needed to adequately predict long-term, net C storage in ecosystems. In this synthesis, we discuss the current status of below-ground responses to elevated CO2 and temperature and potential feedback effects, methodological challenges, and approaches to integrating models and measurements.
AB - Rising atmospheric CO2 and temperatures are probably altering ecosystem carbon cycling, causing both positive and negative feedbacks to climate. Below-ground processes play a key role in the global carbon (C) cycle because they regulate storage of large quantities of C, and are potentially very sensitive to direct and indirect effects of elevated CO2 and temperature. Soil organic matter pools, roots and associated rhizosphere organisms all have distinct responses to environmental change drivers, although availability of C substrates will regulate all the responses. Elevated CO 2 increases C supply below-ground, whereas warming is likely to increase respiration and decomposition rates, leading to speculation that these effects will moderate one another. However, indirect effects on soil moisture availability and nutrient supply may alter processes in unexpected directions. Detailed, mechanistic understanding and modelling of below-ground flux components, pool sizes and turnover rates is needed to adequately predict long-term, net C storage in ecosystems. In this synthesis, we discuss the current status of below-ground responses to elevated CO2 and temperature and potential feedback effects, methodological challenges, and approaches to integrating models and measurements.
KW - CO fertilization
KW - Carbon sequestration
KW - Mycorrhizas
KW - Nutrient cycling
KW - Rhizosphere
KW - Soil carbon
KW - Soil respiration
KW - Soil warming
UR - http://www.scopus.com/inward/record.url?scp=11144353702&partnerID=8YFLogxK
U2 - 10.1111/j.1469-8137.2004.01053.x
DO - 10.1111/j.1469-8137.2004.01053.x
M3 - Review article
AN - SCOPUS:11144353702
SN - 0028-646X
VL - 162
SP - 311
EP - 322
JO - New Phytologist
JF - New Phytologist
IS - 2
ER -