Tree regeneration on seismic lines
Principal Investigator: Greene, David F (5)
Licence Number: 13824
Organization: Department of Geography, Concordia University
Licensed Year(s): 2005 2004
Issued: Jun 06, 2005

Project Description: The purpose of this project is to identify the factors that promote or retard forest regrowth after seismic line cutting. Little was known about tree regeneration on seismic lines until the 2001-2003 study by Seccombe-Hett and Walker-Larsen, which showed that older lines were well-stocked but that the delay in coloniziation might be caused by dramatic subsidence and resulting water-logging. This is the second year of a three-study that involves sowing seeds on selected portions of 30-40 year old seismic lines as well as on very recent lines to assess spruce seedling establishment. Black spruce is sown on upland lines and white spruce in the Delta lines. Another part of the study involves modifying the seedbed (e.g., by roto-tilling, raking, and/or moss shearing) in small plots to determine if these enhance the establishment of seedlings. Also, overtopping shrubs will be removed from plots with a brush-saw to evaluate whether this enhances the growth of seedlings that have already regenerated. The work in 2005 includes repeating the sowings from 2004, doing a census in August, and a re-census of last year's seedlings to see which seedbeds survived the winter best. The researchers will also measure subsidence at old and new lines, as well as active layer depths. They will check to see if the fresh lines near Tsiigehtchic are water-logged. Data will be collected in three main areas: 1) along various seismic lines within 1 km of the Dempster Highway between Inuvik and Tsiigehtchic, 2) the recent Devlan lines about 20 km from Tsiigehtchic, and 3) an old line in the Delta about 10 km southeast of Inuvik. The researchers will use a boat in the Delta, a truck on the Dempster (the lines are walking distance to the road) and ATVs to reach the Devlan lines. Results will be communicated through ARI and GRRB. There will be a Gwich'in student involved in this work for the entire summer. The study will be conducted along seismic lines near Inuvik and Tsiigehtchic from June to August, 2005.