Riparian Forest Buffers

Wooded buffer zones along streams, rivers, and the Bay can be classified as riparian forests. Riparian forests differ from upland forests in their hydrology, plant community, soils, and topography. Learn more about riparian forest buffers, their benefits and functions, and common plants that make up the buffers.

Riparian Forests Improve Wildlife Values

The riparian forest supports a greater diversity of wildlife than nearly all non-aquatic areas or upland forests. The reason for this is because of the numerous habitat features found in these areas. Forested riparian corridors function as connectors between isolated blocks of forested habitat. Riparian forests are often surrounded by low-quality wildlife habitats and therefore support higher densities and diversities of migratory birds. In agricultural areas where extensive forests are not present, riparian forests provide critical habitat and may be the only edge cover available.

Trees and shrubs are required for roosting or foraging by most riparian birds. Mammals depend on the vegetation for food and shelter. The increased humidity of riparian forests makes them important habitat for amphibians, snakes, and turtles. Snags are used as den sites by cavity nesters. Root systems of woody vegetation not only help stabilize banks, but supply cover for fish and aquatic insects.Forest litter is the basis of food in the stream ecosystem, being utilized by insects that are in turn prey for fish.

Riparian Forests Improve Water Quality

Studies have shown that riparian forests as narrow as 50 feet in width can completely remove excess nitrogen as it moves from farm fields through the forests to the adjacent stream. These forested areas also filter sediments and phosphorus, thereby acting as buffers to nutrient inputs to streams. Nutrient retention by a 100-foot forest adjacent to agricultural land is estimated at 80% for phosphorus and 89% for nitrogen. The retention varies depending on width of forest, slope, and other factors.

Tree roots help stabilize streambanks by holding soil in place. Riparian forests also lower flow velocities, causing sediment to settle out. The most important role of the riparian forest is the uptake and long-term storage of nutrients in its woody material.

A major concern to the aquatic environment is the increased nutrients entering a watercourse during and after a harvest operation. Nitrate-Nitrogen is the most common nutrient increased in the stream directly following a harvest; however, the slight increase will again convert to its geological rate in three years. As with sediment, leaving a buffer of 50 feet plus 4 feet for every 1% increase in slope will alleviate a nutrient problem.

Creating and Maintaining Riparian Buffers

Riparian Forest Buffer Tax Credit

Landowners can receive tax reduction incentives to create and maintain these forest buffers.

Riparian Buffer Projects

  • Difficult Run Riparian Project - This case study uses Difficult Run as a model for project development and management due to the successful reforestation of this urban watershed.
  • Hawthorne Village Riparian Project - This urban riparian project received an award from VDOF.
  • Shenandoah BlueWay - The purpose of this Web site (funded through VDOF) is to reach potential river users with information about this stretch of river and attractions in the surrounding area.

Understanding the Science Behind Riparian Forest Buffers

Information and articles from Virginia Tech.

Chesapeake Bay Program Information

  • Directive 94-1 (English, PDF format)
  • Adoption Statement (English, PDF format)
  • Final Report of the Chesapeake Bay Riparian Forest Buffer Panel (English, PDF format)
  • Riparian Forest Buffer Establishment Specifications (English, PDF format)
  • House Bill 1419, 1998 General Assembly (English, PDF format)

Additional information

 

Last modified: Wednesday, 12-Mar-2014 12:51:13 EDT