Introduction to the Appalachian Region
Characterized by its mountainous geography rich in biodiversity and unique culture, the chain of mountains can be divided along geographic and ecological lines into three sections - Northern, Central and Southern. The Central and Southern Appalachians and associated landforms serve as the focal point of the Appalachian Landscape Conservation Cooperative stretching from New York to Alabama .
The region’s diverse topography with long broad ridges, steep slopes, deep gorges and wide intermountain valleys, and geologic stability over long periods of evolutionary history has resulted in a broad range of microhabitats and the presence of numerous relict species and communities. A host of plants, invertebrates, salamanders, crayfish, freshwater mussels and fish are restricted to single watersheds or peaks due to millions of years of isolation and favorable conditions. Over 6,300 plant species are known from the region.
The Appalachian Mountains are among the richest of temperate areas, providing habitat for over 250 birds, 78 mammals, 58 reptiles and 76 amphibians (Pickering et al. 2002). One-third of the known salamander species are found in North America; the highest concentration of these is found in the Appalachian Mountains region. The Southern Appalachians are a global hotspot for aquatic species. Mussel, fish and crayfish richness is unparalleled, in part because streams and rivers drain toward the south, allowing aquatic species to persist during successive glaciations. As a measure of aquatic species richness, 290 fish species are known from Tennessee, more than all of Europe (Stein et al. 2000).
The mountains in the region play a critical role safeguarding and buffering the headwaters of key watersheds that serve the heavily populated regions of the North Atlantic, South Atlantic, and Great Lakes.
The Central Hardwoods The Central Hardwood Forest (CHF) refers to the area where deciduous hardwood species overwhelmingly, but not exclusively, dominate the stands and cover types that occur as repeating units across the landscape. Transition zones where Central Hardwood species mix with species from adjacent regions identify boundaries of the region. These regions are the Northern Hardwood-Conifer Forest along the northern border the Southeastern-Pine Forest along the eastern and southern borders, and the Tall Grass Prairie region to the west. There is a distinctness and cohesiveness to the CHF as its boundaries frequently cut across geographic features. The 18 oak and 10 hickory species that dominate stands from Missouri to West Virginia, and Wisconsin to Alabama unify the region. The more important species such as white, black, and chestnut oak may form essentially climax communities on dry sites or successional communities on moist sites. These species may be regarded as obligate xerophytes and facultative pioneers. Such a successional/stability pattern/process is either absent or difficult to identify in other forested regions. Geographically, the region is also diverse. Physiographic provinces include the unglaciated Blue Ridge Mountains, Appalachian Plateaus, Interior Low Plateaus, and Ozark Plateaus, and the glaciated Central Lowlands. The Mississippi floodplain and Gulf Coastal Plain extend into the region. Bedrock, surface deposits, topography, and the soil mosaic vary from province to province and with subregions within provinces.
Land Cover
Land use patterns vary widely within the Appalachian LCC, depending on climate, topography, soils and human population distribution. General land area cover estimates based on the National Land Cover Dataset indicate that approximately 62% of the Appalachian LCC is forested while agricultural lands represent 26% (pasture/hay/grassland 18% and cropland 8%) of land use.
Conservation and Federal Lands
Federal ownership is approximately 12% in the Appalachian Region, with National Parks and Forests being the primary land holders of the Federal community, at 1,800 and 24,750 square miles respectively. The Department of Defense owns approximately 1,500 square miles, Tennessee Valley Authority 1,190 square miles, and Fish and Wildlife Service approximately 327 square miles.
Historic and Cultural Resources
Human communities across the region are heavily reliant on nature-based industries. Timber, agriculture, mining, and manufacturing were the traditional mainstays of the Appalachian economy into the mid-20th century. More recently other industries such as new energy development have replaced agriculture and mining as more important economic forces. But the region also continues to support many historic traditions such as sport hunting, fishing and outdoor recreation, as part of the area’s cultural heritage.
A Biological “Hotspot” – Habitat and Priority Species
The Appalachian LCC contains the most significant biodiversity “hotspot” east of the Rocky Mountains and is the largest contiguous hot spot area in the nation. The Central and Southern Appalachians are unrivaled in the U.S. for aquatic species diversity and comparable only to China for forest diversity.
Approximately 198 species in this proposed LCC are federally listed as threatened or endangered; of these 108 or 54% are aquatic species (primarily mussels and fish). Numerous invertebrates, salamanders, crayfish, freshwater mussels and fish are restricted to single watersheds or peaks due to millions of years of isolation and favorable conditions. The Southern Appalachians are a global hotspot for aquatic species diversity in part because streams and rivers drain toward the south, which allowed aquatic species to persist during successive glaciations.
The mountain region and drainage system along the Cumberland Plateau represents the richest of temperate areas in North America in terms of biodiversity that evolved due to the Appalachian region’s diverse topography with long broad ridges, steep slopes, deep gorges and wide intermountain valleys and geologic stability over long evolutionary time-scale periods. This unique combination of physical characteristics and history has resulted in a broad range of micro-habitats, and the presence of numerous species and communities that at one time existed in abundance but now only survive in particular places in the region. Significant continuing threats to the endemic biological diversity, as well as the environmental services and benefits to society these provide, include the complete loss, fragmentation, or disturbance to terrestrial and aquatic systems due to expanding energy development, urban and suburban expansion with its attendant pollution and roadways, and changes to hydrologic cycles due to extreme levels of water consumption, withdrawal, and increased variability in climate conditions.
