What are they?
To understand what riparian buffers are, you must first understand what the word "riparian" means. A "riparian area" includes the water source and the adjacent land areas that directly affect or are directly affected by the water source. This could be a stream and its banks, rivers, lakes, flood plains, wetlands, even hillsides that drain into the water source.
A riparian buffer is an area of vegetation, usually trees and shrubs, that is next to a water source and helps to maintain the water source and protect it from surrounding land-use practices.
What do they do and why are they important?
They do a lot and are very important! Buffer zones serve to maintain the integrity of stream channels and shorelines, reduce the impact of pollution sources through trapping, filtering, or using sediments, nutrient and chemicals that run into the water. The dense network of roots developed by the vegetation clings to the soil, preventing erosion. It also creates a massive demand for nutrients, decreasing the likelihood of nutrient pollution in the water. The duff or litter layer created by fallen leaves and twigs breaks the impact of rainfall, and slows its travel decreasing erosion.
These areas also cool the water and provide food and cover to wildlife in and out of the water. Riparian buffer zones are also easily accessible travel corridors for wildlife moving through the area. The trees and shrubs provide habitats for small mammals and amphibians while the fallen leaves in the stream provide food for many aquatic organisms.
Where did they go?
Forty percent of the streams in Pennsylvania have less than 100 feet of riparian buffer surrounding them. For a long period of time, stream health was not considered in the interests of economic growth. Between the timber industry and agriculture, miles of buffer zones suffered. The trees were removed from stream edges and farmers were forced to use every acre for production. Cattle often cause extra problems due to the trampling of stream banks and the added nutrient pollution.
Restoring and Preserving buffer zones
The best way to care for riparian buffer zones is by preserving them. Fencing is becoming a popular option for protecting existing riparian buffer zones. Numerous programs are also in existence that promote the restoration of these buffers. Special programs have also been devised to preserve stream quality on agricultural lands.
For further information on riparian buffer zones and restoration projects see: A Watershed Primer for Pennsylvania This book contains examples of other restoration projects as well as contact lists for the groups involved.