Sediment is one of the leading non-point source pollutants in the U.S and has detrimental effects on biological communities such as aquatic communities; human use such as recreation; and natural processes such as flood water storage. For silvicultural operations, the majority of sediment is produced from erosion on highly disturbed areas, such as skid trails, haul roads, and log landings. Erosion from silvicultural activities not only has the potential to introduce sediment into waterways but can also decrease site productivity through the removal of topsoil. In order to minimize erosion from silvicultural operations, forestry Best Management Practices (BMPs) have been developed, but efficacies of various BMP options are not well documented. This study evaluated five closure and cover BMPs for the control of erosion on bladed skid trails through both field based measurements with sediment traps and soil erosion modeling. The erosion models used were the Universal Soil Loss Equation for Forestry (USLE – Forest), the Revised Universal Soil Loss Equation version 2 (RUSLE2), and the Water Erosion Prediction Project for Forest Roads (WEPP – Forest Roads). Erosion model predictions were also regressed against field based results to determine accuracy. The bladed skid trail BMP treatments evaluated were: 1) water bar only (Control); 2) water bar and grass seed (Seed); 3) water bar, grass seed, and straw mulch (Mulch); 4) water bar and piled hardwood slash (Hardwood Slash); and 5) water bar and piled pine slash (Pine Slash). Field based results show that the Control treatment was the most erosive (137.7 tonnes/ha/yr), followed by the Seed treatment (31.5 tonnes/ha/yr), Hardwood Slash treatment (8.9 tonnes/ha/yr), Pine Slash treatment (5.9 tonnes/ha/yr), and finally the Mulch treatment was the most effective erosion control technique (3.0 tonnes/ha/yr). Model accuracy results show that RUSLE2 performed the best overall. Both USLE – Forest and WEPP – Forest Roads under predicted values on the Control treatment, where erosion rates were very high. WEPP – Forest Roads under predicted these values the most. All models generally show that the Control was the most erosive followed by the Seed, Hardwood Slash, Pine Slash, and Mulch treatments. / Master of Science
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/35714 |
| Date | 08 December 2010 |
| Creators | Wade, Charles Robert |
| Contributors | Forestry, Lakel, William A. III, Aust, W. Michael, Bolding, M. Chad |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | Wade_CR_T_2010.pdf |
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