CGRG Bibliography of Canadian Geomorphology
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Author : Arnaud, E.
Date : 1997
Title : The effects of forestry activity on sediment yield and Recent lake sediments: Vancouver Island, British Columbia [abstr.]
Publication : Geological Society of America, 1997 Annual Meeting, Abstracts with Programs - Geological Society of America, Oct. 20-23, 1997, Salt Lake City, UT.
Issue : 29(6):
Page(s) :
Abstract
Enhanced surface erosion associated with forestry activity is well documented. While some studies have focused on assessing the increase in sediment concentrations of streams, there are unanswered questions about long-term trends of sediment yield. The extent to which an increase in surface erosion is transmitted down valley to storage areas such as lakes also remains to be established. To explore these questions, lacustrine sedimentary records from three logged basins and one unlogged basin on the west coast of Vancouver Island, British Columbia are analyzed for physical and chemical properties. Core correlations based on x-ray photography, and trends in organic content and magnetic susceptibility, allow the calculation of accumulation rates. Chronological control by lead-210 activity and caesium-137 concentrations demonstrates that the cores record approximately 100 years of deposition. Historical information of both natural and human disturbance in the study area is compared with changes in sediment characteristics and sedimentation rates. Indicator properties associated with disturbance are thereby identified. The results show increases in organic content following the onset of logging in the lake basin with the oldest and most extensive logging activity. The sedimentary record is complex and does not show the expected increase in sediment yield.
Bibliography of Canadian Geomorphology