Responses of woody plants to exploratory oil sands disturbances: recovery trajectories for passive (natural regeneration) and active restoration
Dr. Scott Nielsen
Alberta Biodiversity Conservation Chair
University of Alberta
My research focus is in terrestrial ecology (plant & animal) and biodiversity conservation where I work on land use planning and stewardship issues. Much of this work is on assessing the impacts to biodiversity from in situ oil sands disturbances and the development and testing of strategies to either minimize these impacts through geodesign principles or restoration. Our research in the lab combines field-based studies with laboratory computer modelling and analysis, including extensive use of Geographic Information Systems, landscape simulations/scenarios, remote sensing (UAVs), and other methods. We are not tied, however, to any single methodology, discipline or taxa, but rather encourage problem-orientated approaches whereby the question (hypothesis) and application are the most important elements, not the method itself or traditions associated with a particular discipline.
Technologies for Monitoring Tree Recovery on Seismic Lines
My research examined the use of different technologies, in particular, unmanned aerial vehicles (UAV) using low-cost cameras, to quantify tree and vegetation recovery on seismic lines. This included first developing and verifying protocols for UAV flights and post-processing workflow at a standard reference site. And second, collecting and processing data for a representative sample of seismic line disturbances in the Fort McMurray region. This included peatland sites near Fort McMurray and post-fire vegetation recovery of seismic lines near McClelland Lake. This work helped contribute to the development of baseline monitoring tools for seismic line vegetation structure.
This project was completed by fall 2017.
Abiotic Conditions and Natural Tree Recovery on Seismic Lines
My research examines the effects of seismic line attributes on the abiotic environment and their relationship to tree recovery. First, I will use field studies to measure summertime light, temperature, and wind conditions on seismic lines as compared to nearby openings (well pads) and adjacent forests. Second, I will model the trajectory of natural tree recovery on seismic lines using tree growth data and landscape characteristics. The project also considers how current restoration efforts that use mounding further alter the abiotic environment and how that may relate to tree regeneration and growth. The study will contribute to a better understanding of seismic line effects on abiotic factors and spatial patterns of tree regeneration in landscapes impacted by in situ oil sands disturbances.
Effects of mounding on the understory regeneration of seismic lines
My research explores how mounding treatments affect the understory community on seismic lines in Alberta’s treed peatlands. We compare the understory plant communities on mounded seismic lines, un-mounded seismic lines, and in the undisturbed reference forests. We also explore how these communities vary with micro-topographic position. To do this, we sampled the understory vegetation at four different micro-topographic positions: tops of hummocks, slopes of hummocks, level ground adjacent to hummocks, and in hollows. The results of this study can inform efforts to restore seismic lines in treed peatlands.
(Please note that Laureen is a Ph.D. student of the Alberta Biodiversity Conservation Chair program at UofA and will undertake this research as one of her chapters in collaboration with BERA in the Nielsen Team.)
Post-fire tree regeneration on exploratory well pads in jack pine forests
My research explores the relationship between fire severity and tree regeneration post-fire in exploratory well pads in jack pine forests on the Athabasca sand plain. In 2017, I sampled 35 exploratory well pads and adjacent forest conditions (paired plots) that burned in the 2011 Richardson fire (6-years post-fire) to examine patterns in natural tree recruitment for sites varying from low to high fire severity. Belt transects were used to count tree regeneration on and off well pads with fire severity measured based on mature tree mortality for trees adjacent to the well pad. I found that conifer recruitment was higher on well pads than in forest plots in areas that had not experienced fire; however, this trend was reversed at higher fire severity. Furthermore, stands that experienced high overstory mortality from fire had much higher overall conifer regeneration. These results illustrate that wildfire can effectively restore well pads within jack pine forests, especially when fire severity is moderately-high (>50%).
Project completed in spring 2018.
Recovery Dynamics of Woody Vegetation on Seismic Lines
Linear disturbances in the boreal forests of Alberta have led to significant amounts of forest fragmentation. The rate of natural succession/recovery in these disturbances is largely unknown yet necessary to understand for landscape-level restoration planning. Furthermore, it is uncertain how beneficial past reclamation efforts have been and which factors promote natural recovery thus precluding the need for active restoration. My project will examine vegetation succession/recovery dynamics associated with these disturbances across a range of conditions to develop woody vegetative trajectory and succession models. The project entails use of a variety of field techniques, Unmanned Aerial Vehicles, and remote sensing information. Models will aid in understanding and mapping which ecosites are most/least vulnerable, projecting future recovery rates both natural and actively reclaimed, and more broadly assisting with reclamation planning and monitoring efforts in the in situ oil sands region of Alberta.
Effects of Linear Disturbances and Fire Severity on Velvet Leaf Blueberry Abundance, Vigor, and Berry Production in Recently Burned Jack Pine Forests
I am currently finishing my undergraduate degree in Environmental Sciences with a major in Conservation Biology at the University of Alberta. Throughout my undergraduate degree I have had the opportunity to work in the Nielsen lab. I was employed as a research assistant studying the recovery dynamics of woody vegetation on seismic lines. Furthermore, I had the opportunity to conduct my own independent research study. My research is focused on disturbance regimes in the boreal forest and their impacts to understory species, specifically to Velvet Leaf Blueberry. The disturbance regimes that were assessed were fire and linear features (seismic lines). My research suggests some important implications for assessing the ecological effects of fire on linear disturbances associated with energy exploration in the western boreal forest.
This project was completed with a journal publication on the “Effects of Linear Disturbances and Fire Severity on Velvet Leaf Blueberry Abundance, Vigor, and Berry Production in Recently Burned Jack Pine Forests”.
Micro-topographical influences on forest regeneration on disturbed seismic lines
I am currently completing my undergraduate degree in Environmental and Conservation Science at the University of Alberta. This previous summer I had the pleasure of working with The Applied Conservation Ecology Lab assisting PhD student Angelo Filicetti with his current work studying the recovery dynamics of woody vegetation on seismic lines. During this time, I had the opportunity to conduct an independent research study on the effects of microtopography on forest regeneration on seismic lines at different levels of fire intensity and severity. Analysis is still in the works for this project, however, we expect to see some interesting results that may hold implications for future regeneration and management techniques.
This project was completed in 2017 and a journal publication is currently in preparation.