Air Quality Related Values: Linville Gorge Wilderness

The Linville Gorge Wilderness, located in the mountains of western North Carolina, is part of the Pisgah National Forest. It was first designated a wilderness area in 1951. In 1964, with the signing of the Wilderness Act, Linville Gorge became one of the original components of the National Wilderness system and ecompassed 7,575 acres. The gorge is formed by Jonas Ridge on the east and Linville Mountain on the west and is bisected by the Linville River which drops 2,000 feet into the valley below. Elevations range from 1,300 feet on the Linville River to 4,120 feet on Gingercake Mountain. The terrain is extremely steep and rugged with numerous rock formations. It is covered by a dense hardwood/pine forest and a wide variety of smaller trees and other plants.

The Linville Gorge Wilderness has been designated as Class I air quality under the Clean Air Act Ammendments of 1977 and recent additions to the Wilderness has increased the size to 12,002 acres.

Air Quality Related Values (AQRV)

Visibility

The scenic beauty of the landscape is an important characteristic of the wilderness and the attribute most highly valued by visitors. The visual resource includes the Gorge, and the Linville River, rock formations, old growth forests, and flowering vegetation. The Linville River has carved out one of the most rugged gorges in Eastern America. Cliffs and rock outcrops flank both sides of the steep narrow gorge. A chain of curious rock formations - Sitting Bear, Hawksbill, Table Rock, The Chimneys, and Shortoff Mountain create a distinctive profile along the eastern rim of the gorge. A variety of flowering plants, herbaceous and shrubs, occur around these rock formations. The Gorge is covered with an old growth forest dominated by large hemlocks and white pines that are impressive, even at a distance.

Flora

The wilderness vegetation is dominated by the majestic overstory of huge eastern hemlock and eastern white pine. These old growth trees dwarf and humble the visitor. Another important component of the vegetation is the variety of unusual plants that occur around the rock cliffs along the rims of the Gorge. Table Mountain pine, Carolina hemlock, Carolina and purple rhododerons, and sand myrtle are the most noticeable species. The Federally listed , threatened Hudsonia montana is found in only one other place besides the Linville Gorge Wilderness. Vegetation varies with elevation, exposure, soil type and moisture. The wilderness provides the unique opportunity of observing this variation as one travels down into the Gorge and back out again. Depending on which area of the wilderness you are in, you can explore the dark and humid recessses of the hemlock forest or the dry, pine forests with sweet smelling laurel, rhododendron and sand myrtle.

Fauna

The Peregrin falcon, a State of North Carolina endangered species, can be seen hunting and soaring around the rock cliffs in the wilderness. The cliffs provide nesting sites for the falcon in an area where food is abundant.

Air Quality Related Values (AQRV) and Sensitive Receptor Indicators

AQRV Type: FLORA
Sensitive Receptor Sensitive Receptor
Indicator
Concern
Thresholds
Upper
Limit
Lower
Limit
Units Comments
Ozone Sensitive Species Foliar Symptoms Visible Symptoms 30   Percent observed from 6 feet away

AQRV Type: VISIBILITY
Sensitive Receptor Sensitive Receptor
Indicator
Concern
Thresholds
Upper
Limit
Lower
Limit
Units Comments
Representative Site Haziness Change 0.5   Deciviews from natural background

 

Pollutant Exposures

Pollutant Exposures Level Name Comments Upper Limit Lower Limit Units Pollutant Averaging AQRV Sensitive Receptor Sensitive Receptor Indicator
Nitrogen Deposition MODELED CHANGE 0.01   Kilograms Per Hectare - Year Annual Flora Soils Soil Chemistry
Nitrogen Deposition SCREENING VALUES 10 3 Kilograms Per Hectare - Year Annual Flora Soils Soil Chemistry
Ozone N100 Number of hours greater than or equal to 0.100 ppm. 4   Hours April-September Flora Ozone Sensitive Species Biomass Reduction
Ozone W126 Weighting of ozone concentrations in a biologically meaningful way 14.5   Parts per Million-Hours April-September Flora Ozone Sensitive Species Biomass Reduction
Sulfur Deposition MODELED CHANGE 0.01   Kilograms Per Hectare - Year Annual Flora Soils Soil Chemistry
Sulfur Deposition SCREENING VALUES 20 5 Kilograms Per Hectare - Year Annual Flora Soils Soil Chemistry

updated: 9/26/2006

 

 

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