Visualizing Urban Forest Vulnerability in The City of North Vancouver
Zach Ferance
Advisors: Sara Barron & Amy Blood
Abstract
Various features of the urban environment like density, population and affluence impact the vulnerability of the urban forest and can negatively affect its ecosystem services supply. The City of North Vancouver (CNV) is a densely packed urban area where the population is projected to increase 1.3% every year from about 50, 000 to 70,000 residents by 2030 (CNV, 2021). This puts added pressure on the urban forest and reduces the potential value of urban trees and the benefits they provide to the cityscape. Traditionally, vulnerability science has focused on how society and living systems respond to large scale disturbances and tries to measure the resilience, or lack thereof, of these systems in the wake of disastrous events. Only in recent years has this approach been applied to the urban forest in hopes of understanding what causes decline and mortality of urban trees as a result of novel stressors found in the urban environment. In this paper we visualize various indicators of vulnerability and discuss how they may be linked to urban tree decline and mortality. The CNV has a higher than average income and density compared to other Canadian cities which may influence tree vulnerability. Other factors that influence urban forest vulnerability are diversity and age composition (Berland and Elliott, 2014; Hauer et al., 2011) which is important to consider in the CNV where 30% of the total 13186 trees studied are comprised of only 3 Genera which may limit the resiliency of the urban forest as we move into a new climate paradigm (Ordóñez and Duinker, 2015). Additionally, a large proportion of trees are smaller diameter at breast height (DBH) again implying a more vulnerable age class. Although indicators can range among social, ecological and biological origins, applying vulnerability science to the urban forest of North Vancouver can potentially inform management, policy and design.
Download report here: Visualizing Urban Forest Vulnerability in The City of North Vancouver