Ozarks Complex: Getting to Know the NEON Domains

The Ozarks Complex (Domain 08) takes its name from the Ozark Mountains and Plateau, but this diverse domain contains more than just mountains. Stretching across the southern U.S. from eastern Oklahoma and Texas to western Georgia, D08 supports a variety of ecosystems ranging from upland hardwood forests to coastal floodplains. The NEON program field sites in Alabama provide a window into watershed dynamics in the southeastern U.S. 

The Ozarks Complex encompasses 609, 928 km2 (235,494 square miles) that includes all of Arkansas as well as large portions of Missouri, Louisiana, Mississippi, Alabama, and Tennessee; the eastern edges of Oklahoma and Texas; and the western edge of Georgia. All six NEON field sites are located in Alabama. 

The Ozarks, which give the domain its name, is a highland region in Arkansas, Missouri, and Oklahoma that includes two mountain ranges, two large plateaus, and regions of gently rolling hills. The area is characterized by temperate hardwood and mixed forests dominated by oak, hickory, shortleaf pine, and eastern red cedar. Abundant streams, rivers, and lakes are found throughout the landscape. Water moving through the limestone and dolomite bedrock has created a karst topography with numerous caves and sinkholes. In some parts of the Ozarks, rocky hilltops support more desert-like ecosystems with grasses and cacti.

In Alabama, where the NEON field sites are located, the landscape ranges from the hills and highlands of the Appalachian and Piedmont Plateaus to the lowlands of the Gulf Coastal Plains. It is one of the most biologically diverse regions in the U.S., with many distinct ecosystems including forests and woodlands, glades and prairies, swamps and wetlands, and riparian and marine ecosystems. Similar diversity can be found in the neighboring states that make up the remainder of D08.

This biological diversity is a result of a warm, wet climate and a rich geologic past that has created regions with distinct topographic and geologic characteristics. Precipitation varies across the domain, but Louisiana, Mississippi, and Alabama rank 2nd, 3rd, and 4th in the U.S. for annual precipitation, behind only Hawaii. Warm, moist waters from the Gulf Coast contribute to this rainfall. Most of the domain also enjoys warm temperatures, plenty of sunlight and a relatively long growing season. As a result, this is one of the most biologically productive areas in the U.S.

The Mississippi River divides the domain as it makes its way down to the Gulf of Mexico. A complicated network of rivers and streams running into the Mississippi or directly into the Gulf creates lush riparian and wetland systems throughout the region.

Domain 08 has three co-located sets of  terrestrial  and  aquatic  field sites. These sites are situated along the same watershed system, creating a unique opportunity to study hydrology, nutrient transport, and biogeochemical cycling through the watershed. 

• Talladega National Forest ( TALL , Core Terrestrial) and Mayfield Creek ( MAYF , Core Aquatic)
• Dead Lake ( DELA , Relocatable Terrestrial) and Black Warrior River Near Dead Lake ( BLWA , Relocatable Aquatic)
• Lenoir Landing ( LENO , Relocatable Terrestrial) and Lower Tombigbee River at Choctaw Refuge ( TOMB , Relocatable Aquatic)

Alabama and neighboring states are expected to get hotter over the next decades. The region is also likely to see both increased flooding and extended periods of drought. Climate change may bring more frequent and severe tropical storms and hurricanes from the Gulf of Mexico, with impacts that extend far inland. The NEON program will provide invaluable data to help scientists monitor these changes and update climate models.