Alabama is home to 6 different soil areas. The areas are divided based on soils with similar parent materials, or geological material. Although there are 6 major soil areas, each area includes hundreds of different soil series, or named soils. Generally, series names come from a geographical location near where a similar soil was first described.
The band of dark-colored soils extending through Central Alabama and curving upward in to northeastern Mississippi is known as the Black Belt or Blackland Prairie. This region gets its name from the prairie-like vegetation that is common in the area. The Black Belt is part of the Coastal Plain, but these soils formed from clayey deposits laid over a soft limestone, known as Selma chalk.
The Black Belt is the only region in Alabama with extensive regions of alkaline soils (soil pH> 7.0). Early settlers discovered these clayey soils held more nutrients and were generally more productive than the sandier Coastal Plain soils. For this reason, many of the large, antebellum cotton plantations were located in the Black Belt region of Alabama and Mississippi. Black Belt soil color is dark because of the humus, or decomposed organic matter, that often coats the clay particles. However, severe erosion due to intensive farming practices removed much of the dark, rich topsoil.
Though the soils are clayey and can become sticky when wet, they soil can still be worked by hand. Many soils in this region are now low in fertility due to historic erosion of topsoil. Because most of these soils are high in clay, they have poor internal drainage (water doesn’t freely move through them), and B horizons are often not clearly evident. Water escapes through evaporation. Ponds are easy to construct in these clayey soils, therefore aquaculture is a prominent business in the Black Belt. Livestock also thrive on prairie-like grasslands in the region.