Monday, November 2, 2009
Convention Center, Exhibit Hall BC, Second Floor
Soil aggregates play an important role in many soil processes, including solution transport, storage of various nutrients and organic matters, and microbial activity. Past research indicates that microbial activities within soil matrix are highly spatially heterogeneous due to complex pore structure of soil aggregates. X-ray microtomography is a great tool that allows quantitatively describing and comparing aggregate structure and internal organization in aggregates from different soil types, agricultural practices and land uses. In this study, we compared quantitative 3D pore/solid geometry of naturally air-dry aggregates from conventional row-crop agriculture (T1) and native successive vegetation (T7) from LTER main site, KBS, MI.The features we quantified includes several fluid flow related properties, i.e., burn number distribution, pore size distribution, throat area distribution, effective throat/pore radii ratio. Our preliminary results show that comparing to aggregates from T1, T7 aggregates have significantly greater number of larger pores with pore networks in favor of fluid flow.