Treeline Dynamics in the Western Canadian Arctic

Regions: Gwich'in Settlement Area

Tags: biology, forestry, dendrochronology, tree growth, treeline

Principal Investigator: Green, Scott (2)
Licence Number: 14352
Organization: University of Northern British Columbia
Licenced Year(s): 2009 2008
Issued: May 30, 2008
Project Team: Nicole Spiegelaar (MSc Graduate Student, Univ of Northern BC), Sean Sweeney (MSc Graduate Student, Univ of Northern BC)

Objective(s): The project will examine past tree growth patterns at the northern treeline in Western Canada as a baseline to predict future growth responses to climate change. Additionally, we will examine tree regeneration and plant associations at the northern treeline.

Project Description: This licence was issued for the application # 836.

The project will examine past tree growth patterns at the northern treeline in Western Canada as a baseline to predict future growth responses to climate change. Additionally, the researchers will examine tree regeneration and plant associations at the northern treeline.

Growth-ring analyses will be conducted in mature treeline populations. Annual diameter growth in each sample population will be compared to historic annual variation in key climate variables (calculated from local climate data and/or ClimateBC) to identify the primary limitations at each sampling site. Growth sensitivities to climatic factors will be compared among species and sites to generate quantitative “response surfaces”. The researchers anticipate sampling about 20-30 tree populations. For each population, approximately 20 small increment cores will be taken to develop growth chronologies (i.e., average population growth responses). Following sampling, cores will be processed, measured and analyzed in the Tree Ring Lab at the University of Northern British Columbia. Tree regeneration for each tree sample population will be measured using conventional vegetation transects, which will not require any destructive sampling. Additionally, the researchers will be conducting vegetation surveys at the sampling sites to characterize the association of plants in tree populations across the transect. These surveys will require some plant collections to confirm identifications, abundances, regeneration capacity, and productivity. They also propose to set up an array of 3 weather-monitoring stations (1 in each sampling area identified on the attached map) for the summer 2008. The equipment (small datalogger and 3 weather sensors at each monitoring site) would be set up in late May/early June and recovered in late August or early September 2008. This data will provide valuable information about climatic variation along this section of the Dempster Highway.

Town hall meetings, field trips and summary reports will be used to communicate results to the public. Additionally, the research team is happy to consider other presentations that may be of value and use in the northern communities (e.g., school classroom talks).
Fieldwork will be conducted from June 01 to September 30, 2008, along the Dempster highway between Wright Pass and the Peel River.