Global ETD Search
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Showing 1 to 19 of 19 for “"stream crossings"”.
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Soil Erosion from Forest Haul Roads at Stream Crossings as Influenced by Road Attributes
Forest roads and stream crossings can be important sources of sediment in forested watersheds. The purpose of this research was to compare trapped sediment and forestry best management practice (BMP) effectiveness from haul road stream crossing approaches and ditches. The three studies in this …
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The Effects of Stream Crossings and Associated Road Approaches on Water Quality in the Virginia Piedmont
Stream crossings are an integral component of forest road systems that provide access for timber harvesting and silvicultural activities. Stream crossings and their associated approaches are often the most critical point of concern for water quality along forest roads. Several types of crossings …
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Sediment Delivery from Reopened Forest Roads at Stream Crossings in the Virginia Piedmont Physiographic Region, USA
… surface runoff and erosion from forest roads at stream crossings are critical for the protection of aquatic ecosystems in forests. In this research, annual and event-based sediment delivery rates were estimated for reopened legacy roads at forest stream crossings in the Virginia Piedmont …
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Effects of Stream Crossings on Macroinvertebrate Assemblages of the Upper Current River, Ozark National Scenic Riverways, Missouri
This study examined the impact of road crossings on benthic macroinvertebrate communities in a wadeable Ozark river. I collected macroinvertebrates during winter and summer from four riffle locations (upstream, at crossing, downstream, and farther downstream) at each of five sites in the upper …
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Efficacy of operational stream crossing best management practices on truck roads and skid trails in the Mountains, Piedmont, and Coastal Plain of Virginia
… goals are to compare BMP implementation at stream crossings by region and road type in Virginia and to quantify effectiveness of BMPs by developing hypothetical upgrades and determining upgrade costs. Stream crossings (75 truck, 79 skidder) sampled for BMP implementation were on operational …
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Effectiveness, cost, and implications of forest haul road stream crossing structures and best management practices in Virginia
Forest roads and stream crossings have the potential to be sources of sediment from forest operations. Recent litigation has renewed interest in furthering research related to forest road Best Management Practices (BMPs). Three legacy (100 year old) forest road stream crossings were monitored for …
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Sediment Delivery Ratios and Areas of Forest Operational Features by Physiographic Groupings in the Southeastern U.S.
… harvest areas, haul roads, decks/landings and stream crossings, all of which have the potential to influence erosion and sediment deposition in streams. Forestry best management practices (BMPs) were created to minimize the effects of harvesting operations on sedimentation and are implemented …
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Forest Disturbances: Occurrences and Impacts of Recreational, Hydrogeomorphic, and Climatic Disturbances
… riding) recreational trail approaches to stream crossings were found to be 13 times greater than rates for undisturbed forests. Downstream changes in macroinvertebrate-based indices indicated water quality was negatively affected downstream from culvert and ford crossings. These findings …
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Potential Effects of Forestry Best Management Practices and Implementation Rates on Soil and Water Resources in the Southeastern United States
… erosion and potential sediment delivery to streams. Skid trails, stream crossings, forest roads, decks, and harvest areas are major forest operational features that have the potential to erode and deliver sediment to streams. These five features are also common BMP categories evaluated by …
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Fish Passage at UDOT Culverts: Prioritization and Assessment
… providing Aquatic Organism Passage (AOP) at road-stream crossings. Department of Transportation (DOT) emphasis on AOP has been driven largely in response to endangered species listings, other agencies' initiatives, and the desire to restore ecosystem connectivity to watercourses. UDOT is currently …
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Loggers' perceptions of the costs of best management practices on timber harvesting operations in Virginia
… broad base dips, water turn-outs, water bars, streamside management zones, stream crossings, and site stabilization. Loggers provided an estimate of the cost or expense for constructing each BMP. They gave an indication of how costly these practices were to implement. The responses for each BMP …
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Up an Urban Creek: The Role of Development Patterns in Stream Health
… sub-urban areas imposes increasing pressure on stream ecosystems. The "Urban Stream Syndrome" explains the observed negative trends in stream conditions associated with increasingly urbanized watersheds. Urban planners are challenged with addressing increased growth and development while also …
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Assessing Efforts To Reduce Sediment Impacts In Cottonwood Creek, Blackfoot Basin, Montana
… The first objective evaluated trade-offs in stream crossing improvements regarding short-term sediment impacts versus long-term reductions in sediment load from road surface erosion and possible culvert failures. Suspended sediment and turbidity measurements were taken during spring snowmelt …
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Assessing Efforts To Reduce Sediment Impacts In Cottonwood Creek, Blackfoot Basin, Montana
… The first objective evaluated trade-offs in stream crossing improvements regarding short-term sediment impacts versus long-term reductions in sediment load from road surface erosion and possible culvert failures. Suspended sediment and turbidity measurements were taken during spring snowmelt …
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Effectiveness of State Developed and Implemented Forestry Best Management Practices in the United States
… forest roads, skid trails, log landings, stream crossings, and streamside management zones) and physiographic region (Mountains, Piedmont, Gulf Coastal Plain, and Atlantic Coastal Plain). There were numerous research gaps regarding erosion rates from forest operations for all the regions …
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Hydraulic modeling and performance evaluation of low water crossings in Illinois
… old and aging bridges, culverts, and low water crossings on rural low-volume roads that need to be replaced. Low water crossings (LWCs) have been used as an economical alternative to culverts and bridges, designed without overtopping, on low-volume roads where there is a low number of floods. …
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Post Harvest Evaluation of Best Management Practices for the Prevention of Soil Erosion in Virginia
… skid trails, access roads, harvest areas, and stream crossings within each of Virginia's physiographic regions. A secondary objective was to provide a greater level of decision support for VDOF field staff, through the identified key factors which would indicate potential problem areas of …
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Horizontal and vertical structure of velocity, potential vorticity and energy in the Gulf Stream
… was deployed for the first time in the Gulf Stream at 68°W. The temperatures, pressures, and velocities at the uppermost instrument indicate the Gulf Stream moved back and forth across the mooring site, so that the entire Stream was sampled in time; hence the data may be used to examine …
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Skid Trail Stream Crossing Closure Techniques for Protecting Water Quality
The impact of forest roads and skid trails on stream health is being increasingly scrutinized. Forest roads and skid trails have repeatedly been identified as forest operations having the greatest potential to produce sediment by way of non-point source pollution. The stream crossing portion of a …