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At Fort Knox, we used habitat and population models to address three conservation issues. Cerulean warblers (Dendroica cerulea) and Henslow's sparrow (Ammodramus henslowii) are territorial migrant birds that were formerly candidates for federal listing. Cedar barrens (sometimes called slope glades) are unique plant communities that support a number of rare plants and invertebrates.

We developed GIS-based habitat models to predict the locations of habitat for the two bird species and for cedar barrens. These models allow land managers to focus monitoring and management actions in areas most likely to actually contain the species or communities of concern.

We coupled a population demographic model of Henslow's sparrow with the habitat model for Henslow's sparrow so that the persistence of the Fort Knox population of Henslow's sparrows could be evaluated.

The Fort Knox reservation is a 44,595-ha U.S. Army installation in north central Kentucky, covering parts of Bullitt, Hardin, and Meade counties. The reservation adjoins the Ohio River, and is drained by the Salt River and its tributary, the Rolling Fork. Many smaller streams are present in the hilly terrain. Most of Fort Knox is second-growth deciduous forest. Non-forested areas include the cantonment area of the base, and the towns of Radcliff, Muldraugh, and West Point, KY, are also within or adjacent to the reservation. The western third of the reservation has good road accessibility, but there is only limited gravel road access to the northern and southern training areas.

There are 18 training areas just inside the perimeter of Fort Knox where the Army conducts both vehicle-based and on-foot training. Half of the reservation, about 21,332 ha, is an impact area for ordnance where only Army personnel are permitted. Almost all of the floodplains surrounding the Salt River and Rolling Fork lie within this central impact area.

The basic geologic structure at Fort Knox is Devonian shale, overlain by layers of limestone interspersed with layers of dolomite and silty shale. Most of the Fort Knox is underlain by St. Louis Limestone and Salem Limestone, with karst features throughout (KGS 1985). Most soils are Alfisols with some Inceptisols in complex patterns on steep hillsides (Arns et al. 1979, Whitaker and Waters 1986). A few small areas of Mollisols are also present.


REFERENCES

Arns, F. S., M. J. Mitchell, F. C. Watts, and B. L. Wilson. 1979. Soil survey of Hardin and Larue Counties, Kentucky. Soil Conservation Service, USDA, Washington, D.C.

KGS (Kentucky Geological Survey). 1985. Caves and Karst of Kentucky.

Whittaker, O. J., and B. A. Waters. 1986. Soil survey of Bullitt and Spencer Counties, Kentucky. Soil Conservation Service, USDA, Washington, D.C.


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