A Terrain-Attribute Based Approach to Assessing Soil Carbon Sequestration in the Oregon Coast Range Mountains.

Determining how to best mitigate Global Climate Change through the sequestration of atmosphereic CO₂ requires developing an understanding of potential ecosystem C sinks and the rates at which C can be sequestered in soils and vegetation under a variety of land uses.  The largest global terrestrial C pool is soil, but actual total pool sizes as affected by anthropogenic influences across regional and watershed scales is not precisely documented.  Shallow soil sampling, temporal and spatial variability, failure to precisely measure soil bulk density and account for coarse fragments have contributed to uncertainties in soil C pool estimates.  The “bundled value” of soil C as an ecosystem service is largely speculative as well.  Precise data bases with large sample sizes across terrain and biomass components do not currently allow the kinds of robust multivariate analyses required to establish strong correlations among soil C and other important variables.  We outline a hierarchical approach that will be used in complex, highly dissected and intensely leached forested terrain.  The goals will be to examine relationships among soil C, soil-landscape attributes and forest stand density and age with sufficient precision and certainty to allow extrapolation to other basins within the region.