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Each morning, the group would split into two teams of three individuals, with each team’s goal of measuring trees on two sample plots that day. Guided by GPS coordinates and maps provided from West Fraser Integrated Forestry Company, each team would drive on dirt, gravel, or grass roads to get as close to the plot that they could. Once there, they would hike up to two kilometers in dense brush on unmarked terrain in order to find the plot. The plots were circular with a radius of 11.2 m. On the plots, trees were marked with blue paint and a numbered metal tag. The group took measurements on the on each tree that included the diameter, height, height to living crown, species, and class (ranging from dominant to suppressed). The same measurements were taken on the plots in either 2004 or 2006. By re-measuring the plots, researchers will be able to determine how each plot changed in the 12 or 14 years since it was last measured.

The team faced many challenges in taking their measurements. In some instances, they were unable to find the locations of the plots, which had the center marked by a 1m-tall orange stake. The most frequent cause of this was a large fire in 2011 around the town of Slave Lake that burned 40% of the city and many of the sample plots. The group also encountered hazardous conditions traveling to and from the plots each day, with the area’s terrain varying between wet, marshy areas and dry, dense brush. Researchers came across black bears and had to be prepared for encounters with other wildlife, as they were also in grizzly country. Despite these challenges, the team of researchers accomplished their goal of measuring a total of 40 plots of trees. At an average of 80+ trees per plot, the group estimates that they measured over 3,200 individual trees.

The measurements that the team collected will be used to verify models and estimates that are made from various remote sensing techniques, such as satellite imagery and LiDAR.

 

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The team (left to right) – Piotr Tompalski, Yu Chen, Yuhao Lu, Chris Mulverhill, Ignacio San Miguel, Brandon Bung (Photo: Piotr Tompalski).

 

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Yu Chen sizes up a tree before taking measurements (Photo: Piotr Tompalski).

 

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On the plots, each tree was marked with paint and a numbered metal tag (Photo: Piotr Tompalski).

 

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Yuhao Lu uses a GPS unit to search for the plot. Many of the northern plots had been burned in 2011 (Photo: Ignacio San Miguel).

The PRF team: Dr Paul Treitz (Queen's), Joe Rakofsky (McGill), Karin van Ewijk (Queen's), Stacey Leson (UBC), Rachel Perron (UQAM) and Jean-François Prieur (Sherbrooke U./UQAM) (left to right). (Photo: Rachel Perron)

The PRF team: Dr Paul Treitz (Queen's), Joe Rakofsky (McGill), Karin van Ewijk (Queen's), Stacey Leson (UBC), Rachel Perron (UQAM) and Jean-François Prieur (Sherbrooke U./UQAM) (left to right). (Photo: Rachel Perron)

 

The PRF (45o 57’ N, 77o 34’ W) is situated along the Ottawa River, northwest of Ottawa, on the southern edge of the Precambrian Shield. The forest encompasses approximately 10,000 ha and borders Algonquin Park. Its topography has been influenced by glaciation and consists of post-glacial deposits and outwashing, resulting in gently rolling hills with sandy loams or shallow sandy soils with bedrock outcrops. The overstory of this mixed mature forest is characterized by eastern white, red, and jack pine on dry, nutrient-poor sites, and trembling aspen and white birch on upland sites. Tolerant hardwood species such as sugar and red maple are also abundant, especially on nutrient-rich uplands. Red oak, albeit in lower abundances, is found on upper, south- and west-facing slopes with shallow soils while shade-tolerant conifers, such as eastern hemlock, are more commonly found in valleys and on north- and east-facing slopes.

Due to the ongoing research activities at PRF, there is a large network of existing sampling plots which were utilized in this field campaign. In all, a network of 80 plots that encompass a range of species compositions and basal area conditions have been selected for sampling (to meet the needs of the AWARE research questions being investigated). In 2016, the AWARE field crew was able to sample 57 plots, leaving the remainder to be sampled in 2017. For each plot, we measured all trees with a diameter at breast height (dbh) equal to, or greater than 8 cm that fell within a 17.84 m radius from the plot centre (i.e., a sample plot size of 0.1 ha or 1000 m2). Tree measurements included species, status (living or dead), origin (natural or planted), dbh, crown class (e.g., dominant, co-dominant or suppressed), and health or decay class depending on whether the tree was alive or dead. At the plot level we recorded stand development stage, noted indications of disturbances, documented terrain conditions (sloping, wet, rocky, etc.) and took panoramic photographs at the centre of the plot which will be used to create photogrammetric point clouds. Using an SX Blue GPS system, we collected accurate and precise locations of each plot centre. Through a joint data sharing effort with NRCan (Lisa Venier) we will also have access to measurements for trees with a dbh less than 8 cm (i.e., dbh and density of trees within a number of height classes) collected in transects within the 57 sampling plots. Their data collection started in early August and is ongoing.

The field data collected over the month of July coincided with the acquisition of multispectral lidar data by Teledyne Optech’s multispectral lidar system (Titan).  These field data will facilitate the development of methods for modelling tree diameter distributions and tree species identification/classification of the overstory (and potentially the understory).

The team standing around the white pine with the largest dbh in PRF (Photo: Karin van Ewijk)

The team standing around the white pine with the largest dbh in PRF (Photo: Karin van Ewijk)


Joe Rakofsky and Stacey Leson at the truck after finishing a plot. (Photo: Karin van Ewijk)

Joe Rakofsky and Stacey Leson at the truck after finishing a plot. (Photo: Karin van Ewijk)


This survey was carried out to meet the research objectives of the AWARE project led by Nicholas Coops of UBC and funded by NSERC and industrial partners (http://aware.forestry.ubc.ca/). Survey specifications were designed by AWARE researchers Benoît St-Onge (UQAM) and Paul Treitz (Queen's), assisted by Peter Arbour (Operations Manager, PRF, Canadian Wood Fibre Centre) and Teledyne Optech. During the entire month of July, field measurements were collected by a team of AWARE researchers including postdoctoral fellow Karin van Ewijk (Queen's); graduate students Jean-François Prieur (Sherbrooke U./UQAM) and Rachel Perron (UQAM); field assistants Joseph Rakofsky (McGill) and Stacy Leson (UBC); and Paul Treitz. The lidar and field data will serve to quantify tree diameter distributions and identify tree species, among other research objectives.

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Teledyne Optech Titan three channel false-color intensity image of a section of the Petawawa Research Forest (NIR in red, SWIR in green, and green channel in blue).

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The first annual general meeting for AWARE will be held at the Forestry Centre, Grenfell Campus, Memorial University in Corner Brook, NL from May 24th-26th, 2016.  Over the three days, we will present the results of our first year of research, hear talks from local and international speakers, and run two technical workshops.

Please download the program for more information.

AWARE AGM Y1 Program v 1