The Effect of Riparian Forest Management on the Freshwater Environment
SR(02)06F

October 2002

PROJECT SUMMARY

The Forestry Commission's Forests & Water Guidelines recommend that riparian zones should be managed in an integrated way so that the aquatic environment and distinctive riparian habitats are protected or enhanced. This is thought best achieved by maintaining open or partially wooded conditions, with about half the length of a stream exposed to direct sunlight. Where existing conifer crops provide dense shade, it is advocated that these should be cleared back from streamsides and replaced with predominantly broadleaved trees and shrubs. The overall aim is to create an ecologically rich riparian buffer area that will help protect the aquatic zone from disturbance by silvicultural operations on the adjacent land.

Much of this guidance, however, is founded on principal rather than experimental study. In particular, there is a lack of knowledge about how the width of the buffer, the structure of the vegetation and the mix of species affect the main functions of the riparian buffer, which are considered to be: sediment removal and erosion control, protection of water quality, moderation of shade and water temperature, maintenance of habitat structural diversity and ecological integrity, and improvement of landscape quality. Information on these aspects is urgently required to guide the ongoing major restructuring of upland conifer forests.

This report addresses this need through a review of the international literature on the effects of riparian forest management on the freshwater environment, and by revisiting earlier experimental bankside clearance treatments in the UK. It concludes by summarising best management practice for riparian bufferareas. The key findings were:

KEY WORDS
Riparian habitat, conifer bankside clearance, riparian zone width, riparian zone structure, riparian zone management.

Copies of this report are available from the Foundation, price 35.00 less 20% to FWR members