Advisor in Ryerson’s Masters of Spatial Analysis (MSA) and Environmental Applied Science and Management (EnSciMan) graduate programs.
“I forget what I was taught. I only remember what I have learnt.” ~ Patrick White
Chris’ research published in Urban Forestry & Urban Greening:
Who is likely to plant a tree? The use of public socio-demographic data to characterize client participants in a private urban forestation program
City trees, and the ecosystems of which they are a part, provide important benefits to urban residents. In many cities across North America, suitable locations for the planting of trees – expansion of the urban forest – are mostly confined to privately owned land.
Growing conservation through residential shade tree planting
Urban shade trees have the potential to modify their surrounding climate and conserve building energy use. Tree shade cast on residential buildings can lower inside temperatures, decreasing the electricity demand for cooling during hot times of the year.
An interactive mapping tool for urban forest stewardship: fostering appreciation for the benefits of city trees using Google Maps API
Interactive web-based mapping is growing in popularity. With the advent of Google Maps, and similar online mapping tools, a powerful and yet simple medium for engaging the general public in the use of geospatial information has emerged.
Influence of organic mulch on soil temperature moderation in an afforesting urban park
This project investigates the effect of organic mulch on one of the important conditions necessary for tree growth in cities – moderation of soil temperature in the near-surface rooting zone.
Spatio-temporal analysis of forest response to hurricane damage: Point Pleasant Park, Halifax, Nova Scotia
Remote sensing is both a practical and affordable technology for use in the assessment and monitoring of dynamic changes within forested landscapes.
Restoration of the rooting medium: strategic mulching of trees in forested urban parkland
Ensuring good soil quality is essential to promoting plant growth in urban parks and building ecological resilience into a cityscape. While park managers and arborists have emphasized the importance of selecting vegetation adapted to urban conditions, surprisingly little attention has been given to the soil quality and volume necessary for trees to grow to maturity, thus maximizing their ecological and aesthetic values.
Drivers of change in impervious surface cover: the role of socio-demographic and dwelling-specific characteristics
The principal objective of this study was to examine how changes in Toronto’s socio-demographic landscape may have influenced the quantity, quality and distribution of its urban forest and plantable green spaces.
An unwelcome neighbour: the shady side of Acer platanoides
Norway Maple (Acer platanoides) is ubiquitous in most North American cities. Native to continental Europe, its planting was encouraged to replace dead and dying elm (Ulmus spp.) in the mid-1960s. It was selected for its urban-hearty traits including tolerance of air pollution and soil compaction, rapid growth, and high shading potential; its invasive traits went unreported until the early 1990s.
A day of extreme heat and humidity: a spatio-temporal index for heat vulnerability assessment
The public health consequences of extreme heat events are felt most intensely in metropolitan areas where population density is high and the presence of the urban heat island (UHI) phenomenon exacerbates the potential for heat exposure. The purpose of this research was to develop a metric for mapping exposure to heat using meteorological data that would assist public health decision makers in assessing locations of potential vulnerability within their communities.
Institutional valuation of tree cover in a city centre: an urban forest management opportunity
A well-managed urban forest delivers essential environmental services to the city in which it grows. Few entities are better positioned to provide consistent broad-scale maintenance and protection of urban trees than are large downtown institutions. In this study, we investigate the structure and function of an urban forest growing on a large institutional property in the city centre of Toronto, Canada.
Vegetation placement for temperature moderation in an urban microclimate
Inhabitants of densely settled urban centres are especially vulnerable to the impacts of elevated summertime temperatures. Strategic selection and placement of vegetation is one approach to mitigating microclimatic heating in the urban core. To evaluate the temperature-moderating influence of trees and vines, a total of 13 pairs of temperature loggers were installed on eight buildings in downtown Toronto, Canada.
Spatial investigation of photosynthetically active radiation (PAR) and its role in natural regeneration of Quercus rubra: a case study of Kew Gardens Park, Toronto
This research addresses recent concern that natural regeneration of red oak (Quercus rubra) may be declining in eastern North America. It examines the role of understory canopy light, measured as photosynthetically active radiation (PAR), in supporting natural regeneration of red oak within a naturalized area of urban park, located in Kew Gardens, Toronto.
Spatial variability in hurricane damage intensity across a forested urban park: Juan’s impact on Point Pleasant Park, Halifax, Nova Scotia, Canada
Remote sensing techniques have been used effectively in both near real-time and post-event analyses of broad-extent disturbances within forested landscapes. In this project, high spatial resolution imagery (0.6 m pansharpened Quickbird data) was used to map forest disturbance in Point Pleasant Park, Halifax, Nova Scotia, Canada caused by Hurricane Juan in fall 2003.
Structure of a forested urban park: implications for strategic management
Informed management of urban parks can provide optimal conditions for tree establishment and growth and thus maximize the ecological and aesthetic benefits that trees provide. This study assesses the structure, and its implications for function, of the urban forest in Allan Gardens, a 6.1 ha downtown park in the City of Toronto, Canada, using the Street Tree Resource Analysis Tool for Urban Forest Managers (STRATUM).
Drought in the city: soil moisture implications for a forested urban park in downtown Toronto, Canada
For trees in densely built urban settings, already under stress as a result of their surroundings, the increased risk of droughts predicted as a consequence of global climate change adds to the pressure they face. This study examined soil characteristics in a downtown Toronto park in summer 2007, the driest in 50 years. Bulk density, compaction and soil moisture levels were measured at 117 sample locations in Allan Gardens in early May to capture baseline readings at 76 mm and 200 mm (the soil zone where most fibrous roots absorb water).
Naturalization as a strategy for improving soil physical characteristics in a forested urban park
Ensuring good soil quality is essential to promoting plant growth in urban parks and building ecological resilience into a cityscape. Periodically used to restore a degraded urban ecosystem, parkland naturalization is a management approach designed to facilitate the return of an area to a natural state by largely discontinuing maintenance activities and restricting public access.
Estimating land cover distribution and change in Toronto from 1985-2005
The purpose of this study was to estimate the change in abundance and distribution of the predominant land cover surfaces within the City of Toronto between 1985 and 2005. Two Landsat Thematic Mapper satellite images (1985 and 2005) were classified into seven land cover classes. Citywide percentages and associated area of land cover changes were calculated in order to investigate the dynamic composition of Toronto’s landscape with respect to pervious/impervious surfaces, and the density of tree canopy coverage.
Landscape extent response of Adirondack forest to the 1998 Ice Storm
In 1998, an unprecedented ice storm produced a wide swath of forest damage across Eastern Ontario, Southern Quebec, Northern New York State, and much of New England. This study builds upon previously collected data that mapped damage intensity immediately following the storm. It uses a time-series of six Landsat satellite images to investigate vegetation response within the heavily damaged Adirondack Forest, New York State.
Ultra high-resolution imagery for evaluation of urban tree canopy condition
Effective assessment of canopy condition is essential to the management of trees in an urban environment. Most appraisals of tree health are reliant on an evaluation of branching structure and foliar condition, which are usually conducted by an individual standing on the ground looking up into the tree canopy. However, decline, or more localized dieback, frequently begins at the top of the tree crown and may not be readily visible in an assessment that is conducted from below. Such a circumstance is common with large stature mature trees growing in residential neighbourhoods or city parks.
Present and future delivery of ecological services by City of Toronto urban parks trees
An evaluation of the potential for perennial vines to mitigate warming of the urban microclimate
Spatial analysis of the effect of Tillage Radish®, a soil remediating cover crop, on soil compaction and soil nutrient content in a Toronto urban park
Spatial analysis methods for trails planning within environmentally significant areas: a case study in Toronto, Canada
In this study, spatial analysis was used to evaluate the changes in core area habitat, or those areas outside the disturbance zone of trails, within four of Toronto's priority ESAs. Results indicate that between 19 and 49% of high quality habitat (core areas) of these ESAs may be lost in the near future, (within the next 10-20 years) under a "no management" scenario where ad-hoc trails and existing uses progress unrestricted.