8.4 Human Impacts on Wetlands and Mangroves

Wetlands and mangroves provide huge value

Wetlands are land areas saturated with water, either permanently or seasonally, that support unique plant and animal life. Mangroves are salt-tolerant trees/shrubs in coastal tropical/subtropical zones. Both provide ecosystem services: flood control, water filtration, storm-surge buffering, carbon storage, groundwater recharge, and habitat/nursery grounds for fish and birds.

Humans destroy these ecosystems for development

Wetlands and mangroves are drained, filled, or cleared for agriculture, aquaculture (shrimp farming), urban development, and coastal construction. This destroys habitat, releases stored carbon, and removes natural buffers against flooding and storm surge, increasing damage from hurricanes and coastal erosion.

Consequences and conservation

Loss of wetlands/mangroves reduces biodiversity, worsens water quality (less natural filtration), and increases flood/storm damage to nearby communities. Conservation strategies include restoration projects, legal protection (e.g., Clean Water Act wetland regulations), mitigation banking, and sustainable aquaculture practices to reduce further clearing.

Key terms

Wetland

Land area saturated with water permanently or seasonally, supporting unique plants and animals and providing flood control and filtration.

Mangrove

Salt-tolerant tree/shrub found in coastal tropical/subtropical regions; buffers storm surge and provides habitat.

Ecosystem services (wetlands/mangroves)

Flood control, water filtration, storm buffering, carbon storage, and habitat/nursery grounds for wildlife.

Major cause of mangrove/wetland loss

Conversion for agriculture, aquaculture (e.g., shrimp farming), and coastal urban development.

Wetland protection policy example

The Clean Water Act requires permits for activities that fill or alter wetlands in the U.S.

Try an AP-style question

What ecosystem service do wetlands provide for water quality?

1. They filter pollutants from water
2. They add pollutants to water
3. They raise water temperatures
4. They block all groundwater flow