. Does harvest in west slope Douglas-fir increase peak flow in small forest streams?. Logging Environmental aspects; Forest influences; Stream measurements. period of rapid change were omitted from the analysis. By the beginning of the 1965 water year, trees had been felled on over 80 percent of the drainage and logs had been yarded from 70 percent. Logging was completed during the summer of 1966, and the entire drainage was broadcast burned in October of 1966 (fig. 2). Reestab- lishment of vegetative cover was rapid after burning, although there has been almost no accumulation of litter,and b
. Does harvest in west slope Douglas-fir increase peak flow in small forest streams?. Logging Environmental aspects; Forest influences; Stream measurements. period of rapid change were omitted from the analysis. By the beginning of the 1965 water year, trees had been felled on over 80 percent of the drainage and logs had been yarded from 70 percent. Logging was completed during the summer of 1966, and the entire drainage was broadcast burned in October of 1966 (fig. 2). Reestab- lishment of vegetative cover was rapid after burning, although there has been almost no accumulation of litter,and bare soil has remained near 50 percent (table 1). To obtain sufficient data on larger storms after logging, it was necessary to extend analysis over the 1965-69 water years even though logging was not com- pleted until the summer of 1966. These years include a rather wide range of con- ditions changing from 20-percent old-growth. Figure 2.—Clearcut and logged watershed on H. J. Andrews Experimental Forest the first year after burning. Table ~\ .--Total understory vegetation cover and exposed mineral soil after clearoutting of timber and after burning of logging residue on clearcut watershed Year Condition Vegetation cover—^ Bare ground— Percent 1962 Undisturbed 86 4 1963 Being harvested 1964 Being harvested 1965 Being harvested 1966 After logging 54 12 1967 After burning 30 53 1968 Revegetati ng 76 54 1969 Revegetating 75 48 Source: Dyrness 1965, 1967, and unpublished data. — Sum of crown canopy coverage in the understory is the total of all layers. For comparison with postlogging measurements, the 1962 data do not include overstory tree cover. 2/ — Bare ground may occur under vegetative cover. Thus, vegetative cover plus bare ground can add to greater than 100 percent. l. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resembl
Size: 1745px × 1432px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, booksubjectfores, booksubjectstreammeasurements
