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Lower Mississippi-Gulf Water Science Center - Tennessee
ABOUT THE Tennessee WSC
USGS IN YOUR STATE
USGS Water Science Centers are located in each state.
Environmental Flow Research in the Tennessee River Basin
More about … Place is more important than land use for influencing streamflow
Ecoregions are areas with characteristic and generally unique ecosystems. A variety of physical and biological factors such as geology, geography, vegetation, climate, soils, land use, wildlife and hydrology influence and define these broadly-defined ecosystems. Ecoregion classifications range from Level I (coarsest level with 15 ecoregions) to Level IV (finest level). We used Level III ecoregions in our study.
The Interior Plateau Level 3 ecoregion extends from southern Indian and Ohio to northern Alabama. Geology within the Interior Plateau consists of Mississippian to Ordovician-age sedimentary rocks such as limestone, chert, sandstone, siltstone and shale. Landforms include hills, irregular plains and tablelands; elevations in this ecoregion are lower than elevations further east in the Appalachian ecoregions (i.e. Blue Ridge). Vegetation in the area is mainly oak-hickory forest with some prairie and cedar glades. The Interior Plateau has a diversity of fish species.
The Blue Ridge extends from southern Pennsylvania to northern Georgia. The Blue Ridge is mountainous with narrow ridges, hilly plateaus and some peaks greater than 6,600 feet. Geology in the Blue Ridge consists mainly of metamorphic rocks with some small areas of igneous and sedimentary geology. Annual precipitation is highly variable, ranging from over 100 inches to 40 inches in particular areas. The southern portion of the Blue Ridge has some of the highest biodiversity in the eastern United States.
Further descriptions of Level 3 ecoregions can be found at USEPA Western Ecology Division:
Omernik, J.M., 1987, Ecoregions of the conterminous United States. Map (scale 1:7,500,000). Annals of the Association of American Geographers, v. 77, no. 1, p. 118-125.
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