Effects of forest clear-cutting on abundances of oxygen and organic compounds in a mountain stream of the Marmot Creek basin

Refractory compounds in the waters of streams draining the Marmot Creek basin in the east slopes of the Rocky Mountains appeared to increase as a result of forest clear-cutting. The vegetation of the basin is dominated by spruce – subalpine fir forests. Clear-cutting was done at six selected sites, each about 10 ha in size. The saleable wood was harvested and the slash was left on the ground. The effect of clear-cutting was most pronounced in the case of tannins and lignins, with concentrations being increased by as much as a factor of four. The effect appeared to persist for several years, from the onset (and completion) of the clear-cutting in 1974 to near the end of the decade. Humic substances were increased to a much lesser degree (from 790 to 900 μg/L) and the effect died out in less than 2 years. Forest clear-cutting appeared to have no effect on the abundances of oxygen and labile organic compounds.Direct data were not available for the refractory and labile compounds in the mountain stream prior ...