What are Wetland Ecological Services?
Goods and services contributing to human well-being by an ecosystem are called ecosystem services. Wetland ecosystem services are those direct and indirect goods and services that wetlands provide just by existing within a dynamic community. Recently, efforts have been made to assign a dollar value to the ecological services provided to society by wetlands.
What is the Value of a Wetland?
One of the economically valuable roles wetlands play is pollutant filtration. As an example, a bottomland hardwood swamp in South Carolina was studied for its filtration services. It was found that the swamp removed a quantity of pollutants from the surrounding watershed equal to that of a water treatment plant. The cost-saving of protecting the wetlands was estimated at $5 million, or the cost of building the water treatment plant (EPA publication 832-R-93-005).
Wetlands also buffer surrounding areas from flood damage. Wetlands soak up rain runoff, reducing the frequency and intensity of flooding. Maintaining only 15% of the land area of a watershed in wetlands can reduce flood peaks by as much as 60%, saving enormous costs on flood damage (EPA publication 843-F-06-004).
The Conservation Fund (in collaboration with Houston-Galveston Area Council and Houston Wilderness) assessed ecosystem services in the 13-county Houston-Galveston region. This assessment estimated ecological systems provide the region $15 billion dollars per year of water quality, air quality, water supply, flood protection, and carbon sequestration benefits.
Of this number, wetlands serve as local water storage reserves providing services totaling $9,000/acre/year. Wetlands were also estimated to reduce flood damage by $8,000/acre/year by absorbing stormwater. The cost saving for removal of carbon from the atmosphere is $2 of damage prevention annually per ton of carbon removed. Wetlands are estimated to store between 81 and 216 metric tons of carbon per acre. Forests and prairies store their share of carbon as well (between 47 and 74 metric tons per acre for forests and 78 tons per acre for prairies).1
What Services do Wetlands Provide?
The following is a list of some of the ecological services provided by wetlands:
Wetland Ecological Services2:
- Habitat and Biodiversity
- Nature Tourism
- Commercial and Recreational Fisheries
- Recreation
- Hunting and Fishing Revenues
- Nutrient Regulation
- Reduced Water Purification Costs
- Soil and Sediment Regulation
- Reduced Water Purification Costs
- Reduced Soil Erosion
- Disturbance & Natural Hazard Regulation
- Storm Surge Mitigation
- Runoff and High Water Event Mitigation
- Cultural Values and Aesthetics
- Water Supply
- Increased Water Quantity
- Increased Downstream Productivity (fisheries, etc.)
- Food Production
- Food (both plant and animal) and fiber harvest
1Conservation Fund, Houston-Galveston, Green Infrastructure and Ecosystem Services Assessment, 2013, last visited April 14, 2015 here: http://www.conservationfund.org/images/projects/files/Houston_Galveston_Report.pdf
2Woodward, Richard T. and Yong-Suhk Wui. 2000. “The Economic Value of Wetland Services: a Meta-analysis”.Ecological Economics 37: 257-270.