Ecoregion

For each site in Trek Birmingham, you’ll see we identify its ecoregion. An ecoregion is part of a mapping system based not on cities and counties, but on ecology. Plants and animals don’t pay much attention to human boundaries – a tree doesn’t know if it’s Alabama or Georgia and a bird flits easily across state or county lines — but biologists rely on maps to document species distribution, so they use to ecoregions to show where plants and animals can be found.

Although most commonly used by scientists, the ecoregion concept can help us all understand the landscape in which we live, work and play.

Ecoregions point out patterns in the landscape that determine not just where plants and animals make their homes, but where we do, too. That’s especially the case in Birmingham, where the region’s initial growth was spurred by nearby natural resources for industry and the proximity to rich farmlands to feed its population.

Ecoregions are sorted into four levels, from the very large to the detailed. Each marks a geographic area with a shared climate, geology, topography and similar water and soil throughout. When those things are the same, the ecosystems found there will look alike, too.

Each ecoregion gets a roman numeral depending on its size. In Level I, all of North America, from the Maine coast to the Louisiana swamps to the California desert, is divided into just 15 ecological regions. Each level then has more divisions, culminating in several hundred Level IV ecoregions.

Alabama has 29 Level IV ecoregions, which is one of the reasons the state has such rich biodiversity and can claim more species than any other state east of the Mississippi River. At level III, where Alabama has six, they align with the physiographic regions used by geologists, another demonstration of how geology shapes our state’s terrain.

Curious how Birmingham’s ecoregions vary?

Here in the Birmingham metropolitan area, there are two Level III ecoregions: the Ridge and Valley and the Southwest Appalachians. This is how they break down:

The Ridge and Valley (Level III) Ecoregion

is made up of parallel ridges and valleys formed by geological folding and faulting. The ridges and valleys come in a variety of widths, heights and stone, including limestone, dolomite, shale, siltstone, sandstone, chert and mudstone. About half of the region is covered with forests; there are plenty of springs and caves; and the streams and rivers support a huge number of fish and other animals. The Ridge and Valley Ecoregion has three Level IV ecoregions within it in our area:

The Southern Limestone/Dolomite Valleys and Low Rolling Hills Ecoregion

which we’ll call the Limestone Valleys and Hills – is mostly broad valleys and rounded hills with many caves and springs. There are forests of oak and pine or oak and hickory, plus agricultural, industrial and urban lands.

The Southern Shale Valleys Ecoregion

also consists of broad valleys, but with fewer, smaller hills mainly dominated by shale. The soils here tend to be deep, acidic, moderately well-drained and slowly permeable. Many of the steeper slopes are used for pasture or have gone back to forest.

The Southern Sandstone Ridges Ecoregion

is mostly sandstone but also has shale, siltstone and conglomerate. The ridges are steep and forested with stony, sandy soils that aren’t very fertile. Elsewhere, most of the ridges are narrow, but in Alabama, the Coosa and Cahaba ridges are broader. A good example of how the sandstone bedrock affects the look of the ecoregion can be found at Moss Rock Preserve.

The Southwestern Appalachians (Level III) Ecoregion

stretches from Alabama north to Kentucky as a patchwork of forests, woodlands and croplands over low mountains. Here, the planet’s crust was forced steeply upwards when the continents collided to form the Appalachian Mountains. This region includes some of Alabama’s most dramatic mountain scenery, including Sand Mountain, Lookout Mountain and the Jackson County Mountains. Within it, there is one level IV ecoregion in our area:

The Shale Hills Ecoregion

also called the Warrior Coal Field – which covers most of Walker County to the west of Birmingham — has the lowest elevation in the Southwest Appalachians but is still very hilly. The bedrock is mostly shale, silt and sandstone that are hard for water to flow through, making for smaller streams. The land is mostly forested, but extensive coal mining has left open-pit mines that have changed the landscape.

To read more about ecoregions, go to the Environmental Protection Agency’s map here.

 

Ecoregion of Homewood Forest Preserve

The steep mountain slopes of the Homewood Forest Preserve and Shades Creek’s valley are diagnostic features of the Southern Sandstone Ridges level IV ecoregion of the Southern Appalachian Mountains. This ecoregion is known for its long, sandstone-capped ridges, which loom … Continue reading

Watershed of Homewood Forest Preserve

The waters flowing from Homewood Forest Preserve feed Shades Creek, which flows past the base of the preserve. Shades Creek is one of the most important tributaries to the Cahaba River, and the Cahaba is one of the world’s most … Continue reading

Ecoregion George Ward Park

George Ward Park, like much of Jones Valley, falls within the Southern Limestone/Dolomite Valleys and Low Rolling Hills level IV ecoregion. This is a landscape where dolostone and limestone lie just below the surface. These rock formations yield numerous springs, … Continue reading

Ecoregion of Cahaba River Walk

Alabama’s longest free flowing river, the Cahaba  is approximately 194 miles long with two distinct biological areas – above the fall line (upper Cahaba River) and below the fall line (lower Cahaba River).  The headwaters form in St Clair County. … Continue reading

Ecoregion of Avondale Park

Avondale Park, like much of Jones Valley, falls within the Southern Limestone/Dolomite Valleys and Low Rolling Hills level IV ecoregion. This is a landscape where dolostone and limestone lie just below the surface. These rock formations yield numerous springs, sinkholes, … Continue reading

Ecoregion of Red Mountain Cut

Ecoregions of AWC

The Alabama Wildlife Center in Oak Mountain State Park falls within the Southern Sandstone Ridges (level IV) ecoregion of the Ridge and Valley (level III) ecoregion.  This level IV ecoregion includes both the sandstone-capped ridges and the intervening valleys that … Continue reading

EcoRegion of Railroad Park

Railroad Park rests on the floor of Jones Valley and is part of the Southern Limestone/Dolomite Valleys and Low Rolling Hills (level IV) ecoregion.  Bedrock of limestone and dolomite has shaped the topography and ecology of this and other valleys … Continue reading

WDNWR Ecoregion

 The Southern Limestone/Dolomite Valleys and Low Rolling Hills level IV ecoregion is karst topography – a landscape dominated by limestone and dolostone. Hills throughout are made of chert and sandstone. The karst provides springs, caves, and alkaline soils that in … Continue reading

Ecoregions of Roebuck Spring

The Southern Limestone/Dolomite Valleys and Low Rolling Hills level IV ecoregion is karst topography – a landscape dominated by limestone and dolostone. Because most of the ecoregion is valley, the karst provides numerous springs and sinkholes. Caverns are found beneath … Continue reading

Ecoregion of Shades Creek Greenway

From any open spot along the Greenway, you will see steep hills and mountain slopes on either side of the valley. This is classic terrain of the Southern Sandstone Ridges level IV ecoregion of the Southern Appalachian Mountains. This ecoregion … Continue reading

Ecoregion East Lake Park

East Lake Park lies within the Southern Limestone/Dolomite Valleys and Low Rolling Hills level IV ecoregion. Known as karst topography, this is alandscape dominated by limestone and dolostone. Because most of the ecoregion is valley, the karst provides numerous springs … Continue reading

Red Mountain Park Ecoregion

Red Mountain is something of a misfit within its ecoregion. Ecoregions are geographic areas sharing a similar ecology, geology, and climate. They are sorted into four nested levels, from very inclusive to very precise. Red Mountain, all of Alabama, and … Continue reading

Ecoregion of McWane Science Center

The McWane Science Center rests on the floor of Jones Valley and is within the Southern Limestone/Dolomite Valleys and Low Rolling Hills level IV ecoregion. This ecoregion is one of karst topography – a landscape dominated by limestone and dolostone … Continue reading

Ecoregions of Turkey Creek Nature Preserve

Turkey Creek Nature Preserve is one of the few public outdoor areas in the metro area where you can walk across the boundary of two Level III Ecoregions.  Turkey Creek flows out of the Level III: Ridge and Valley │ Level IV: … Continue reading

Ecoregion of the Birmingham Botanical Gardens

The Birmingham Botanical Gardens span two level IV ecoregions within the Ridge and Valley level III ecoregion.  The slightly hilly southern portion of The Gardens is within a pocket of the Southern Shale Valleys level IV ecoregion, which itself is … Continue reading

Ecoregions of the Birmingham Zoo

Most of the Birmingham Zoo is within the Southern Shale Valleys level IV ecoregion, which itself is nested within the Ridge and Valley level III ecoregion, one of the major level III ecoregions of the Southern Appalachian Mountains.  The terrain … Continue reading

Ecoregions of Sloss

Sloss Furnaces rests on the floor of Jones Valley and is part of the Southern Limestone/Dolomite Valleys and Low Rolling Hills (level IV) ecoregion.  Bedrock of limestone and dolomite has shaped the topography and ecology of this and other valleys … Continue reading

Ecoregions of SEC and Hugh Kaul Ecoscape

Perched on a hill of Copper Ridge Dolomite, the Southern Environmental Center, the Hugh Kaul Ecoscape and Birmingham-Southern College are situated within the Southern Limestone/Dolomite Valleys and Low Rolling Hills (level IV) ecoregion of the Ridge and Valley (level III) … Continue reading

Ecoregions of Moss Rock

Moss Rock Preserve falls squarely within the mountains of the Southern Sandstone Ridges (level IV) ecoregion of the Ridge and Valley (level III) ecoregion.   The massive boulders and the sunny glades at the preserve formed from sandstones of the Pottsville … Continue reading

Ecoregions of Oak Mountain State Park

Oak Mountain State Park falls within the Southern Sandstone Ridges (level IV) ecoregion of the Ridge and Valley (level III) ecoregion.  This level IV ecoregion includes both the sandstone-capped ridges and the intervening valleys that comprise the southern portions of … Continue reading

Ecoregions of Ruffner

Occupying a portion of Red Mountain, Ruffner Mountain Nature Preserve is located within the Southern Limestone/Dolomite Valleys and Low Rolling Hills (level IV) ecoregion of the Ridge and Valley (level III) ecoregion.  Red Mountain’s unique geology sets it apart from … Continue reading

Ecoregions of Vulcan Park

Though Vulcan stands high on a ridgeline above downtown Birmingham, he and the museum belong to the Southern Limestone/Dolomite Valleys and Low Rolling Hills (level IV) ecoregion of the Ridge and Valley (level III) ecoregion. As it turns out, Red … Continue reading