Effects of forest harvesting best management practices on surface water quality in the Virginia coastal plain

Three watersheds located in Westmoreland County, Virginia were monitored to evaluate effectiveness of forestry best management practices (BMPs) for minimizing hydrologic and water quality impacts associated with timber harvesting. One watershed was clear-cut without implementation of BMPs, one watershed was clear-cut with the implementation of BMPs and the third watershed was left undisturbed as a control. The 27 months of pre-harvest monitoring data and 17 months of post-harvest monitoring data were compared using the paired watershed regression analysis and the minimum detectable change (MDC) statistic. Analysis of the hydrologic data showed that peak discharge rates were not impacted by harvesting, regardless of whether BMPs were implemented. Harvesting with or without the implementation of BMPs resulted in no statistically significant change in stormflow volume. BMP implementation was found to be effective in minimizing harvesting impacts on stormflow total suspended solids (TSS), ammonia, total Kjeldahl nitrogen (TKN), total nitrogen (TN), sediment-bound nitrogen and total phosphorous (TP) concentrations and total flow TSS and TP concentrations. BMP implementation was also effective in minimizing harvesting impacts on stormflow TSS, TKN, sediment-bound nitrogen, TP and sediment-bound phosphorous loadings and total ammonia loading. The BMPs were not effective in reducing nitrate concentrations and loadings. The BROOK90 forest hydrology model was used to predict the site hydrology. Model predictions compared favorably with streamflow measurements from watersheds QN3 and QN4 until the time of harvest, but did not predict streamflows as accurately for the control watershed, QN5.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Biological Systems Engineering

Department dc:contributor.department

Biological Systems Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1996

Author dc:creator

• Frazee, Joseph W.

Chair dc:contributor.committeechair

• Mostaghimi, Saied

Committee members dc:contributor.committeemember

• Aust, W. Michael
• Heatwole, Conrad D.
• Perumpral, John V.

• best management practices
• paired watershed
• nonpoint source pollution
• forest management
• forest modeling

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-09042008-063552

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/44522