CGRG Bibliography of Canadian Geomorphology
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Author : Floyd, B.; Hudson, R.; Dodd, I.; Hrachowitz, M.; Weiler, M.; and Alila, Y.
Date : 2006.
Title : Recovery of stand-level hydrologic processes following forest harvesting in coastal watersheds: Developing and testing an empirical model.
Publication : Annual Scientific Meeting of the Canadian Geophysical Meeting, May 14-17, 2006. Banff Centre, Banff, Alberta. Abstracts Volume.
Issue :
Page(s) : 48-49.
Abstract
It is well known that forest cover interacts with precipitation to alter watershed inputs. A forest canopy intercepts rain and snow, some of which is returned to the atmosphere, and also regulates snow melt (radiation and rain on snow (ROS) melt). Harvesting can alter the delivery of water to the soil in both rate and volume by altering the structure of the forest canopy, resulting in potential increases in stream flow. A hydrologic recovery model has been created to forecast proportional changes in water inputs that occur as a result of forest harvesting and subsequent regeneration. The model was developed using snow course, rainfall, throughfall and stemflow data from high and low elevation sites on the Sunshine Coast and Vancouver Island, collected within old growth stands, regenerating stands and clear-cuts. A set of curves predicts rate of recovery of snow melt and/or interception processes with respect to stand height based on the elevation of the site and the precipitation regime. The model is currently being tested by implementing an innovative stand precipitation measurement network at Russell Creek watershed on Northern Vancouver Island. The hydrology of Russell Creek watershed is dominated by rain on snow processes. Traditional methods which use only snow survey information at weekly or bi-monthly intervals often miss events associated with a transient snowpack, especially in late fall and early winter. In order to capture this information, a series of snow melt lysimeters has been installed within different aged forest stands ranging from 500 to 1000 meters in elevation, coupled with a dense network of precipitation gauges. This instrumentation, along with bi-weekly snow course measurements, provides valuable event based information regarding snowfall, snow accumulation on the ground and subsequent water output rates as a result of ROS and snowmelt events under a range of canopy conditions. Preliminary results from 2005-2006 will be presented to test the empirical model described above.
Bibliography of Canadian Geomorphology