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The Burd
Run watershed is an ideal setting for an environmental laboratory due
to its proximity to SU (the stream flows through campus), its manageable
scale, and its diverse physical characteristics. Burd Run at the SU campus
drains a watershed of 51.8 km2.
Burd Run heads atop South Mountain, the local name given to the northern
part of the Blue Ridge, at an elevation of 591m. There, two mountain tributaries
flow through the Michaux State Forest, an area of sandy soils developed
on Cambrian quartzite. Near the base of South Mountain, these tributaries
combine and flow across thick Pleistocene colluvial deposits that support
mixed forestry and agriculture eventually emerging into the Cumberland
Valley. As the colluvium thins with distance from the base of the mountain,
several units of Ordovician and Cambrian limestone are exposed (Root 1965),
some of which include solution cavities and other karst features (Shirk
1980). Agriculture is the primary land use on the silt loam and clay loam
limestone soils until the stream flows into the Borough of Shippensburg.
Urban land uses dominate the lower watershed, where the stream eventually
flows across the SU campus at an elevation of 189m.
Water quality varies considerably with geology and land use. For example,
pH readings in the forest/quartzite environment are acidic (pH = 4.5),
whereas water flowing through the limestone terrain of the Cumberland
Valley is buffered (pH = 7.5). Temperature, turbidity, dissolved oxygen,
and other water quality parameters also vary considerably in the different
watershed environments. This variability among topography, geology, land
use, and water quality provides an excellent field laboratory for a wide
range of course projects and investigations.
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