Changes in Forest Floor and Water Quality Following Thinning and Clearcutting of 20‐Year‐Old Pine

Abstract

Effects of timber cutting on forest floor, sediment movement, and chemical quality of percolating water and of plot runoff are reported for pole‐size loblolly pine (Pinus taeda L.) plantations on fragile soils of the upper Coastal Plain. Treatments were clearcut, thin, and nocut. Water quality measurements were derived for runoff samples from 0.002‐ha plots and for percolating water from zero‐tension lysimeters at a 15‐cm depth. Forest floor on clearcut plots was reduced to near the minimum regarded as necessary for site protection within two years. Regardless of cutting treatment, more N and P were coming into the plots via precipitation than were leaving via plot runoff and percolation combined. More K appeared to be leaving the sites than was coming in via rainfall, regardless of cutting treatment. Sediment concentrations in plot runoff tended to be proportional to cutting intensity. Nutrient content in percolation waters was unrelated to cutting intensity. Nutrient concentrations in plot runoff were high compared to concentrations reported in stormflows from local, small catchments with similar characteristics, but plot runoff was <3% of annual rainfall.

Soil erosion and overland flow in forested areas with pine plantations at coastal mountain range, central chile

“…The annual average value of the concentrations of the plots without and with residues were 9.5 and 5.8 times higher than the control plots during the first measurement year, whereas in the second year they were 4.8 and 1.9 times higher (Table 11). The average concentrations of 59 and 83 mg 1-' of the control plots are similar to the levels of 25-79 mg I-' found by McClurkin et al (1987) in Pinus tadea plantations and to 71 mg 1-' reported by IroumC (1990), measured as suspended sediments in a watershed partially forested with Pinus radiata in the south of Chile.…”

Changes in stream chemistry and nutrient export following a partial harvest in the Catskill Mountains, New York, USA

“…Although partial cutting is more common than clearcutting (Nyland, 1992), relatively few studies have examined the effects of partial harvests on stream quality. Some studies indicate that partial cutting, whether in the form of tending (McClurkin et al, 1987;Steele et al, 1991) or regeneration cuts (Patric, 1980;Messina et al, 1997;Wheeler et al, 2000) or selective cutting (i.e., high-grading) (Bäumler and Zech, 1999), may have less impact on stream chemistry than clearcutting.…”

Soil and Economic Loss Evaluation on Small Hillside Farms in the Central Mountains of Honduras

“…In terms of management implications, these results showed that runoff volume will increase as the rainfall increases, regardless of management practices or land uses, as stated by McClurkin et al (1987). In contrast, sediment production does not have a tight association with the amount of precipitation and it can be reduced mainly by the land uses and/or the conservation measures associated with it.…”

“…Smaller plots with rainfall simulators and larger plots with natural rainfall presented some inaccuracies (Rivera, 2004). Plots were delineated by driving strips of thin-gauge sheet metal (25-cm width) into the ground (7 cm), and a metal collector was dug into the lower end (Wischmeier & Smith, 1978;McClurkin, Duffy, & Nelson, 1987;Figueroa Orozco, Cortez, & Pimentel, 1991). Dimensions of the metal collector were determined by calculating the maximum runoff volume for a storm recurrence interval of 5 yr. A recording rain gauge was installed at the site.…”