Author: Frederick John Swanson Publisher: ISBN: Category : Aquatic ecology Languages : en Pages : 20
Book Description
Large organic debris in streams controls the distribution of aquatic habitats, the routing of sediment through stream systems, and the stability of streambed and banks. Management activities directly alter debris loading by addition or removal of material and indirectly by increasing the probability of debris torrents and removing standing streamside trees. We propose that by this combination of factors the character of small and intermediate-sized streams in steep forested terrain of the Pacific Northwest is being substantially altered by forest practices.
Author: Frederick John Swanson Publisher: ISBN: Category : Organic water pollutants Languages : en Pages : 24
Book Description
"Large organic debris has historically been an important element in small mountain streams of the Pacific Northwest. The debris serves to slow the movement of water and inorganic and fine organic matter through the channel. Debris may remain in the channel for decades or longer, and tends to stabilize some sections of a streambed and stream banks while destabilizing other areas. The combination of clear cutting and the complete removal of large debris in a channel may deprive a stream of this natural feature of streams for a century or longer. The consequences are likely to be downcutting and channelization" of the stream, accelerated transport of fine organic and inorganic sediment, and a possible decrease in biological productivity of the stream ecosystem. Therefore, stream debris management during logging operations should include leaving undisturbed the natural, stable organic debris in the channel.??The principal factors controlling the concentration, stability, and functions of stream debris are the history and condition of the surrounding timber stand, flushing history of the channel, stability and abundance of bedload material, steepness of the channel and adjacent hillslopes, and slope stability in the drainage. Because of this complexity, each stream presents a unique situation, which should be inspected in the field and considered on an individual basis before a debris management decision is made."
Author: Frederick John Swanson Publisher: ISBN: Category : Organic water pollutants Languages : en Pages : 24
Book Description
"Large organic debris has historically been an important element in small mountain streams of the Pacific Northwest. The debris serves to slow the movement of water and inorganic and fine organic matter through the channel. Debris may remain in the channel for decades or longer, and tends to stabilize some sections of a streambed and stream banks while destabilizing other areas. The combination of clear cutting and the complete removal of large debris in a channel may deprive a stream of this natural feature of streams for a century or longer. The consequences are likely to be downcutting and channelization" of the stream, accelerated transport of fine organic and inorganic sediment, and a possible decrease in biological productivity of the stream ecosystem. Therefore, stream debris management during logging operations should include leaving undisturbed the natural, stable organic debris in the channel.??The principal factors controlling the concentration, stability, and functions of stream debris are the history and condition of the surrounding timber stand, flushing history of the channel, stability and abundance of bedload material, steepness of the channel and adjacent hillslopes, and slope stability in the drainage. Because of this complexity, each stream presents a unique situation, which should be inspected in the field and considered on an individual basis before a debris management decision is made."
Author: John D. Stednick Publisher: Springer Science & Business Media ISBN: 0387690360 Category : Technology & Engineering Languages : en Pages : 321
Book Description
The Alsea Logging and Aquatic Resources Study, commissioned by the Oregon Legislature in 1959, marked the beginning of four decades of research in the Pacific Northwest devoted to understanding the impacts of forest practices on water quality, water quantity, aquatic habitat, and aquatic organism popu- tions. While earlier watershed research examined changes in runoff and erosion from various land uses, this study was the first watershed experiment to focus so heavily on aquatic habitat and organism response to forest practices. The Alsea Watershed Study, as it came to be known, extended over 15 years with seven years of pretreatment calibration measurements, a year of treatment, and seven years of post-treatment monitoring. The research was a cooperative effort with scientists from Oregon State University, Oregon Department of Fish and Wildlife, the U.S. Geological Survey, and the U.S. Environmental Protection Agency. Cooperating landowners included the Georgia-Pacific Corporation, the U.S. Forest Service, and a local rancher. It was a remarkable 15-year partnership marked by excellent cooperation among the participants and outstanding coordination among the scientists, many of whom participated actively for the entire period.
Author: Frederick John Swanson
Author: Frederick John Swanson
Author: Frederick John Swanson
Author: Frederick J. Swanson
Author: Frederick John Swanson
Author: 
Author: 
Author: John D. Stednick
Author: Mason D. Bryant
Author: C. Kerry Overton