Do pre-fire disturbances influence post-fire nitrogen cycling and regeneration?
Rumbaitis-del Rio, Cristina *,1, 2, Wessman, Carol 1, 1 University of Colorado, Boulder, CO2 Columbia Univerisity Earth Institute, New York, NY ABSTRACT- This study evaluates the hypothesis that prior disturbance conditions modify the initial effects of a stand-replacing wildfire on soil nitrogen (N) availability, net N mineralization rates, vegetation cover, and seedling density. The study area is a northern Colorado coniferous subalpine forest that was disturbed by catastrophic windthrow in 1997, salvage-logging in 1999, and wildfire in 2002. In the first two growing seasons after the wildfire, newly established conifer seedlings were found in previously undisturbed burned areas, but not in burned blowdown or burned salvage-logged areas, possibly reflecting the lack of seed trees as a result of pre-fire disturbances. A greater abundance of invasive species were found in previously disturbed burned areas relative to previously undisturbed burned areas. Fire increased inorganic N avail
