There is much current scientific and political interest in the possibility of sequestering organic carbon in agricultural soils as a means of mitigating the threat of global warming. Increasing soil organic matter is also critical to enhancing soil quality and soil fertility. Thus government action agencies, farmers, environmental groups, and commodity brokers are all interested in the development of new agricultural practices that enhance sequestration of organic carbon in agricultural soils. Much of the current research in this area is focused on evaluating the impact of various agricultural management practices on soil carbon sequestration and in developing verifiable means of quantifying soil organic carbon sequestration. Relatively little attention has been paid to the physical, chemical, and biological processes that are responsible for the formation and stabilization of organic carbon in soils. Soil clay minerals are believed to play a critical role in these processes. The workshop will help fill a critical gap and position the participants to play a larger role in future scientific discussion of the topic. Note that a special technical session "Carbon Stabilization by Clays" will be held during the general meeting in Santa Fe.

• The nature of clay-humic complexes and their ultrastructure, Michael Thompson and David Laird
• Microbes, clays, and humic interactions, Javiera Cervini-Silva and Rebecca Sutton
• Metal-humic interactions and stabilization, Yona Chen
• Clay surface catalysis, Javier Gonzalez
• Clay size and organo-mineral complexes, Claire Chenu
• The nature of humic materials: Physical vs chemical fractionation of humic materials and their significance, Michael Hayes
• NMR spectroscopy of natural organic matter, Robert Wershaw

Javiera Cervini-Silva
Institute of Geophysics
UNAM, Mexico City
javiera@eps.berkeley.edu

David A. Laird
National Soil Tilth Laboratory
Iowa State University
laird@nstl.gov