Exploring Tennessee’s Wetlands

big-Tennessee-Wetland-Reelfoot-National-Wildlife-Refuge-2048x1365

Wetlands are among the most dynamic and diverse ecosystems on Earth. These areas, often found where water meets land, provide critical environmental, economic, and recreational benefits. In Tennessee, wetlands are a vital part of our state’s natural landscape, offering habitat to countless species, improving water quality, and playing a crucial role in flood mitigation. But what exactly are wetlands, and what types can be found in Tennessee? Let’s explore!

What Are Wetlands?

According to the U.S. Environmental Protection Agency (EPA), wetlands are areas where water covers the soil or is present either at or near the surface of the soil all year or for varying periods during the year, including during the growing season. These areas can support a unique variety of plant and animal life adapted to water-saturated conditions.

Basically, ALL wetlands have three common characteristics:

  1. Hydrology
  2. Hydrophytic Plants
  3. Hydric Soils

Those may sound complicated, so let’s break it down.

HYDROLOGY

Water presence in wetlands can be permanent, frequent, or seasonal.
The water may be above, below, near, or at the soil surface, with water coming from groundwater flow, surface flow, or precipitation.

HYDROPHYTIC
PLANTS

Hydrophytic means “water-loving” and these plants have evolved to survive in water and the low-oxygen environments typical of waterlogged soils that are unique to each type of wetland ecosystem.

HYDRIC SOILS

Hydric soils are saturated, flooded, or ponded long enough during the growing season to create low oxygen in the upper part. The presence of water and low soil oxygen levels lead to gradual changes in soil properties.

Because of this unique combination of water + plant + soil makeup in the ecosystem, wetlands are “engineered” to do some amazing things. Wetlands are often referred to as “nature’s kidneys” due to their ability to filter pollutants and improve water quality. They also serve as “sponges,” absorbing excess water and reducing the impact of floods. But more on that later!

Types of Wetlands in Tennessee

Tennessee’s varied landscape—from its Great Smoky Mountains in the East to Memphis along the Mississippi River—hosts a wide range of wetland types. Here are the primary types you’ll find in our state:

Reelfoot Lake
© Jeremy Atherton, 2001

Bottomland Hardwood Forests

Bottomland hardwood forests are seasonally flooded woodlands typically found along rivers and streams. These wetlands are characterized by trees such as oaks, cypress, and tupelos. In Tennessee, they are often located in the western part of the state near the Mississippi River.

Where To Find In Tennessee:
Duck River Wildlife Refuge
© Angie Tabb

Scrub-Shrub

Scrub-shrub wetlands, dominated by dense woody vegetation under 20 feet tall like buttonbush, willow, and cottonwood, are frequently flooded habitats in shallow slackwater areas that offer vital nesting and cover for waterfowl and wading birds during the breeding season.

Where To Find In Tennessee:
Morrison Meadows
Photo: TDEC

Wet Meadows

Wet meadows, common in eastern and central Tennessee, are marshes in lake basins and poorly drained flats that periodically flood after heavy rain, reducing downstream flooding while supporting diverse grasses, sedges, and wildflowers that provide habitat and food for insects, amphibians, and songbirds.

Where To Find In Tennessee:
Schoolyard Springs
© Paul Kingsbury

Mountain Bogs

Mountain bogs, rare wetlands in East Tennessee’s low-lying mountain areas, feature acidic, nutrient-poor soils that support unique habitats for rare species like the American cranberry and southern bog turtle.

Where To Find In Tennessee:
Isolated Wetlands
Photo: UT/Matt Grey

Isolated Wetlands

Isolated wetlands are small, scattered wetlands not connected to larger water systems, often found in low-lying areas where water collects. These wetlands, which can vary widely in size and duration of flooding, provide critical habitat for amphibians, insects, and other wildlife, while also helping to recharge groundwater and filter pollutants.

Why they matter:

Isolated wetlands are vital ecosystems that provide the same support and functions as larger wetlands. Despite their small size and apparent isolation, they are connected to the waterways surrounding them via groundwater and they play a crucial role in maintaining ecological balance.

Benefits of Wetlands

Despite their importance, wetlands are one of the most threatened ecosystems globally and in Tennessee. Tennessee has lost up to 60% of our state’s wetlands, we cannot afford to lose any more of these wonderful and productive ecosystems. Protecting these areas is critical not only for wildlife but also for the health and safety of human communities. Let’s look at some of the benefits they provide for us:

Water Quality Improvement

Wetlands act as natural filters, trapping pollutants, excess nutrients, and sediments before they reach larger water bodies. This process not only maintains healthier ecosystems but also reduces water treatment costs for nearby communities.

Flood Mitigation

By absorbing and storing excess water during heavy rains, wetlands help mitigate flooding in surrounding areas. This is particularly valuable in Tennessee’s river basins, where flood risks can be significant. Just one acre capable of storing up to 1.5 million gallons of water.

Recharging Our Aquifers

Tennessee’s underground aquifers supply drinking water for over one million residents, support industries, and irrigate crops, making them essential for the state. Wetlands play a critical role in recharging these aquifers by allowing rainwater to seep into the ground.

Supporting Biodiversity

Wetlands are vital habitats that support the state’s extraordinary biodiversity, many species found nowhere else in the world. These ecosystems provide food, shelter, and breeding grounds for countless plants, fish, birds, and amphibians critical to ecosystem health.

Outdoor Recreation

Outdoor activities like fishing, hunting, kayaking, and hiking not only bring joy to residents and visitors but also fuel our economy.
Outdoor recreation in Tennessee generates $13 billion annually, supports 103,618 jobs, and accounts for 3.1% of employers.

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