We recently attended a talk by the botanist-ecologist Dr. Spira, sponsored by the Asheville Mushroom Club. It was a great overall introduction to the geophysical-fauna-flora interactions of our new home. Some interesting tidbits I learned:
The southern Appalachians have a very high level of flora diversity. With 3000 species of fungi, 2500 flowering plants, 130 trees, and 400 mosses it is one of the most species-rich temperate forests in the world.
A variety of factors contribute to the region’s diversity. There are 3 National Parks and 6 National Forests creating the highest concentration of public land in the eastern US. While extensively logged in the early 1900s due to railroads linking the region to the export market, the terrain makes large scale agriculture and urban development difficult.
Geography, geology, and precipitation levels vary widely in the southern Apps. Pockets of temperate rain forest created by altitude changes can receive 90 inches of rain a year, while the Asheville basin averages only 45 inches. Topsoil can be virtually nonexistent on rocky outcrops to deep in rich coves. Soil pH ranges from acidic, like in heath bald communities (mountain laurel & rhododendron) to basic for shrub-limited hardwood habitats coves with high amounts of limestone or dolomite.
During the last ice age (Pleistocene) there was a lack of glaciation in the region resulting in less species loss. The northern Appalachians like Europe lost many species during this period due to glaciation. However, glaciers did gouge natural depressions for swamps and lakes, which are noticeably absent from the southern Apps.