Kp. Timoney et G. Peterson, FAILURE OF NATURAL REGENERATION AFTER CLEAR-CUT LOGGING IN WOOD BUFFALO NATIONAL-PARK, CANADA, Forest ecology and management, 87(1-3), 1996, pp. 89-105
Logging of boreal riparian old-growth white spruce took place in Wood
Buffalo National Park from 1951 to 1991. In this study we focus on one
of the areas, Timber Berth 408, logged from 1966 to 1991, Regeneratio
n surveys of white spruce were conducted in clearcuts and undisturbed
vegetation during June 1994. The age of a clearcut is unrelated to eit
her white spruce stocking or density over a 25 year period. Post-loggi
ng natural regeneration in clearcuts has failed: median stocking (% fr
equency in 10 m(2) plots) and density (stems ha(-1)) of seedlings are
18.2% and 300 ha(-1), and of transgressives are 14.3% and 200 ha(-1).
Median stocking and density of spruce (including residual growth) in t
he cutover areas are 36.4% and 848 ha(-1). In order to achieve the lev
el of stocking found prior to logging, approximate to 93% of the logge
d area, or 9300 ha, would require planting. There is a clear relations
hip between spruce stocking rates and densities in clearcuts and the d
istance to the nearest white spruce seed tree. White spruce seed tree
distance is important in determining the ability of a clearcut to rege
nerate naturally, Failure of post-logging natural regeneration in Wood
Buffalo National Park is attributable primarily to two factors: (1) l
arge size of the clearcuts, placing most of any area logged beyond the
effective dispersal distance of white spruce seed; (2) destruction of
advance growth and lack of residual growth. Clearcutting and site pre
paration are shown to degrade boreal riparian ecosystem structure and
function. Recommendations are provided whose goals are to maintain bio
diversity and healthy ecological structure and function in boreal ripa
rian ecosystems.