Disturbance
Seminar: The USGS Debris-Flow Flume: Past, Present, and Future
Event Date:
Thursday, November 30, 2017
Event Brief Description:
GEOTECHNICAL LECTURE SERIES: The USGS Debris-Flow Flume: Past, Present, and Future
RICHARD M. IVERSON, PH.D., Senior Research Hydrologist, U.S. Geological Survey
ABSTRACT: The U.S. Geological Survey debris-flow flume is a unique, large-scale experimental facility located at the H.J. Andrews Experimental Forest in the Willamette National Forest, Oregon. Research on the dynamics of debris flows, landslides, and related phenomena began there in 1992 and continues today. More than 160 experiments have been conducted to date. Detailed instrumental monitoring of reproducible, appropriately scaled experiments at the flume has yielded data that have served to both motivate and test new mathematical models of landslide and debris-flow processes, and some of these models are now in widespread practical use. This presentation will provide a brief overview of the factors that spurred development of the debris-flow flume facility and of the scientific advances that have resulted from experimentation there.
BIOGRAPHY: Richard (Dick) Iverson is a senior scientist at the USGS Cascades Volcano Observatory in Vancouver, Washington, where he has worked for more than 33 years. Previously he received a B.S. degree from Iowa State University as well as two M.S. degrees and a Ph.D. from Stanford University. His research focusses on the dynamics of debris flows and landslides as well as other geomechanical phenomena. In the early 1990’s he oversaw design and construction of the USGS debris-flow flume at the H.J.Andrews Experimental Forest, and since that time he has been in charge of science and operations at the facility. Iverson is a fellow of the Geological Society of America and the American Geophysical Union, and has received the Kirk Bryan Award, E.B. Burwell Award, Jahns Lectureship, and Langbein Lectureship from these organizations.
Location: Kearney 112, OSU Campus
Date: November 30, 2017
Time: 4:30 PM
Multi-decadal legacy of clearcutting reaches into neighboring forests
Clearcuts often create stark boundaries between forest habitats. These ecological “edges” can seriously affect neighboring undisturbed ecosystems for some distance in from the edge, perhaps representing a multi-decadal legacy of has clearcutting. A new study led by David Bell took on the question of how historical timber harvests have affected the structure of neighboring old-growth forests in western Oregon.
fire
Much of the Andrews Forest watershed has experienced more recent fire over the last 150 years, ranging in severity from ground low-severity understory fire that killed few adult trees to so-called stand-replacing fires that killed most or all of the old-growth trees that established approximately 500 years ago.
Summer streamflow deficits from regenerating forest
There is much discussion about how plantation forestry affects streamflow in dry (lowflow) seasons, especially as climate change may exacerbate water scarcity. Analysis of 60‐year records of daily streamflow from eight paired‐basin experiments in the Andrews Forest revealed that the conversion of old‐growth forest to Douglas‐fir plantations had a major effect on summer streamflow.
Harvested Area
The first timber harvest at the Andrews Forest occurred in 1951 to study the effects of logging on hydrology, sediment yield, and nutrient losses. Later harvests were done to test different harvesting techniques. Learn more about the history of the Forest on our History page.
First Harvest
The first timber harvest at the Andrews Forest occurred in 1951. Scientists initiated three sets of experimental watersheds designed to study the effects of logging on hydrology, sediment yield, and nutrient losses. Treatments included clearcutting and partial cutting, and one watershed was left in its “natural” forested condition as a control. Learn more about the history of the Forest on our History page.