SOIL NUTRIENT AND VEGETATION RESPONSE TO PATCH CLEAR-CUTTING OF AN ASPEN FOREST NEAR MEADOW LAKE, SASKATCHEWAN

Alternate silviculture systems, such as small patch clearcuts, may bec ome important in the development of sustainable forest management stra tegies in aspen forests. A study was initiated in a 64-yr-old tremblin g aspen (Populus tremuloides Michx.) stand in Meadow Lake Provincial P ark, Saskatchewan to determine changes in nutrient dynamics and second ary succession following patch clear-cutting. One hectare replicated p atch cuts were logged in the winter of 1993-1994. There was no site pr eparation following harvest. Annual vegetation, regeneration and soil and plant nutrient data were collected annually, 1 yr prior to, and 3 yr following harvest. Aspen regeneration was 48 375 stems ha(-1) 2 yr after treatment. Stand (alpha) diversity of the understory was not aff ected by harvesting, although annual species turnover (beta diversity) increased slightly after harvest. There was an increase in aspen foli ar nitrogen (N) for 2 yr following harvest. Soil nutrient concentratio ns did not differ between patch cut and unharvested plots except total potassium (18% lower in the LFH of the harvested treatments 3 yr afte r harvesting). Small patch cuts with the litter horizon kept intact ma y be appropriate for aspen-dominated stands in the boreal mixed wood t o minimize ecological disturbance while maintaining aesthetics within a park setting.