|
|
The Wetland
Ecosystem of the Loess Hills
Wetlands are one of three distinct ecosystems
found in the Loess Hills of Iowa.
Definition of a Wetland
Wetlands are places where
the soil is saturated with water for at least several weeks during
the year. Many wetlands
have shallow standing water throughout the year, but others have
water only during the spring when heavy rainstorms or melting snow
increases the amount of water in the area. Wetlands are also places
where the water is shallow enough for plants to grow. (The deep
water of a pond or lake is not a wetland. These waters are called
aquatic habitats.)
Wetlands Capture
Water
Wetlands in the Loess Hills are found at the base of the slopes
or in ravines
between the hills. These wetlands act as sponges, absorbing water
that comes rushing down the hills during a rain. Wetland plants
(ex., sedges, rushes) filter the water, cleaning it before it moves
on.
Within the Loess Hills
working landscape, the wetlands serve several purposes.
| 1. |
They
act as tourist destinations and educational areas. |
| 2. |
They
provide habitat for plants and animals, increasing the biodiversity
of the area. |
| 3. |
They
filter sediment from water as it runs down the hills. |
Threats
When the majority of the plant cover in a prairie or forested habitat
above a wetland is removed, loess soil washes into the wetlands with
each rain. As the wetlands fill with sediment, they are unable to
support native wildlife, or absorb and filter the water. This causes
an increase in flooding across roads, in low-lying areas, and in basements
of homes located near the base of the hills. Mounds of eroded sediment
cover the landscape, creating hazards for humans and wildlife and
costing money for clean-up. |
