380-6 Effects of Restoration Burning On Soil Nutrients In Pinus Echinata Sites of Eastern Tennessee.



Wednesday, October 19, 2011
Henry Gonzalez Convention Center, Hall C, Street Level

Jennifer Knoepp, Katherine Elliott and James Vose, USDA Forest Service (FS), Otto, NC
 We examined the effects of restoration methods on degraded shortleaf pine-hardwood forests impacted by southern pine beetle (SPB) induced tree mortality. Restoration methods included, cutting SPB killed pines and thinning fire-intolerant hardwoods followed by prescribed fire on dry (DCB) and sub-mesic (MCB) sites; prescribed fire only (BURN); and no treatment (REF).  We examined restoration treatment impacts on ecosystem structure and function.  We hypothesized that these treatments would result in a range of fire intensity and severity and consequently produce a gradient in soil carbon and nutrient responses.  We estimated fire severity (as a function of fire temperature + duration, forest floor loss, and fine fuel consumed) and measured soil C, N, and P, soil solution inorganic N and P, and soil available N and P before and after restoration treatments.  We found the greatest fire intensity and severity on DCB, however all burn treatments resulted in significant loss of down wood and forest floor mass.  Total soil C and N decreased significantly following the DCB treatment.  BRN and DCB treatments resulted in increased available soil N and P the first growing season.  Following treatment, soil solution NH4- and NO3-N and PO4-P at 60 cm depth increased on DCB only suggesting nutrient losses from these sites through leaching.
See more from this Division: S07 Forest, Range & Wildland Soils
See more from this Session: General Forest, Range and Wildland Soils: II