Monday, November 13, 2006
83-1
Computed Tomographic Characterization of Soil Pores as Influenced by Restoration of Prairie Ecosystems.
Ranjith P. Udawatta, Center for Agroforestry, 203 Anheuser Busch Natural Resources Building, University of Missouri, Columbia, MO 65211, Stephen H. Anderson, University of Missouri, Dept. of Soil, Environmental & Atmospheric Sciences, 302 ABNR Building, Columbia, MO 65211, Clark Gantzer, Univ. of Missouri, 330 AB Natural Resources, 330 AB Natural Resources, Columbia, MO 65211, United States of America, and Harold Garrett, University of Missouri-Columbia, 203 ABNR, Columbia, MO 65211.
Prairie ecosystem restoration is believed to improve water infiltration and reduce runoff. It is hypothesized that one reason for these changes is increased soil porosity, especially soil macroporosity. Soil cores were collected to a 50-cm depth in 10 cm increments with six replicates from a mature prairie (MP), a restored prairie (RP), a conservation reserve program (CRP) treatment, and a corn field to evaluate distribution of computed tomography (CT)-measured macropores (>1000 micro-m diam.) and coarse mesopores (60 to 1000 micro-m diam.) as influenced by prairie restoration. Computed tomographic images of soil cores were acquired using a medical x-ray CT scanner. Morphological features and pore characteristics (number of pores, porosity, pore diameter, and circularity) were evaluated by public domain software Image-J to compare differences among treatments. Soil bulk density and saturated hydraulic conductivity were determined and correlated with CT measured pore parameters. Results of this study indicate that mature prairie systems had the highest CT-measured number of pores, macroporosity, and mesoporosity. In contrast, soils from the crop field had the lowest values for these properties. Soil properties evaluated on the restored prairie were second to the MP and better than the CRP treatment. The CRP treatment was better than the crop treatment in terms of CT-measured soil parameters and soil physical properties. The results of the study demonstrated that restoration of prairies improves soil physical properties. Therefore, it could be speculated that use of native grasses and forbs adjacent to agricultural land under row crop management could be of assistance in improving water quality for water resources.
Handout (.pdf format, 154.0 kb)