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Ecological forestry is based on the idea that forest patterns and processes are more likely to persist if harvest strategies produce stand structures, return intervals, and severities similar to those from natural disturbances. Taylor et al. (2020) reviewed forest natural disturbance regimes in Nova Scotia, Canada, to support implementation of ecological forestry. In this follow-up paper, we (i) review the use of natural disturbance regimes to determine target harvest rotations, age structures, and residual stand structures; and (ii) describe a novel approach for use of natural disturbance regimes in ecological forestry developed for Nova Scotia. Most examples of ecological forestry consider only the local, dominant disturbance agent, such as fire in boreal regions. Our approach included: (i) using current ecological land classification to map potential natural vegetation (PNV) community types; (ii) determining cumulative natural disturbance effects of all major disturbances, in our case fire, hurricanes, windstorm, and insect outbreaks for each PNV; and (iii) using natural disturbance regime parameters to derive guidelines for ecological forestry for each PNV. We analyzed disturbance occurrence and return intervals based on low, moderate, and high severity classes (60% of biomass of living trees killed, respectively), which were used to determine mean annual disturbance rates by severity class. Return intervals were used to infer target stand age-class distributions for high, moderate, and low severity disturbances for each PNV. The range of variation in rates of high severity disturbances among PNVs was from 0.28%*[year.sup.-1] in Tolerant Hardwood to 2.1%*[year.sup.-1] in the Highland Fir PNV, equating to return intervals of 357 years in Tolerant Hardwood to 48 years in Highland Fir PNVs. As an example, this return interval for the Tolerant Hardwood PNV resulted in target rotation lengths of 200 years for 35% of the PNV area, 500 years for 40%, and 1000 years for 25%. The proposed approach of determining natural disturbance regimes for PNV communities and calculating target disturbance rates and corresponding harvest rotation lengths or entry times appears to be a feasible method to guide ecological forestry in any region with a strong ecological land classification system and multiple disturbance agents. Key words: natural disturbance, ecological forestry, sustainability, potential natural vegetation, ecological land classification, landscape planning. La foresterie ecologique est fondee sur l'idee que les patrons et les processus forestiers ont davantage de chances de persister si les strategies de recolte produisent des structures de peuplements, des intervalles de retour et des niveaux de severite similaires a ceux des perturbations naturelles. Taylor et al. (2020) ont examine les regimes de perturbations naturelles des forets en Nouvelle-Ecosse, au Canada, afin d'appuyer la mise en ceuvre de la foresterie ecologique. Dans cet article de suivi, les auteurs (i) passent en revue l'utilisation des regimes de perturbations naturelles pour determiner les rotations cibles de recoltes, les structures d'age et les structures des peuplements residuels ; et (ii) decrivent une nouvelle approche d'utilisation des regimes de perturbations naturelles dans la foresterie ecologique developpee pour la Nouvelle-Ecosse. La plupart des exemples de foresterie ecologique ne tiennent compte que de l'agent de perturbation local et dominant, comme le feu dans les regions boreales. Leur approche comprenait (i) l'utilisation de la classification ecologique actuelle des terres pour cartographier les types de communautes de vegetation naturelle potentielle (VNP) ; (ii) la determination des effets cumulatifs des perturbations naturelles de toutes les perturbations majeures, dans leur cas le feu, les ouragans, les tempetes de vent et les epidemies d'insectes pour chaque VNP ; et (iii) l'utilisation des parametres du regime de perturbation naturelle pour deriver des lignes directrices pour la foresterie ecologique pour chaque VNP. Ils ont analyse la presence des perturbations et les intervalles de retour en fonction des classes de severite faible, moderee et elevee (60 % de la biomasse des arbres vivants tues), qui ont ete utilises pour determiner les taux de perturbation annuels moyens par classe de severite. Les intervalles de retour ont ete utilises pour deduire les distributions cibles des classes d' age des peuplements pour les perturbations de severite elevee, moderee et faible pour chaque VNP. La gamme de variation des taux de perturbations de severite elevee parmi les VNP etait de 0,28 %*annee (--1) dans la VNP des feuillus tolerants a 2,1 %*annee (--1) dans la VNP des sapins de moyenne montagne, ce qui correspond a des intervalles de retour de 357 ans dans la VNP des feuillus tolerants a 48 ans dans la VNP des sapins de moyenne montagne. a titre d'exemple, cet intervalle de retour pour la VNP de feuillus tolerants a donne lieu a des durees de rotation cibles de 200 ans pour 35 % de la superficie de la VNP, de 500 ans pour 40 % et de 1000 ans pour 25 %. L'approche proposee, qui consiste a determiner les regimes de perturbation naturelle pour les communautes de VNP et a calculer les taux de perturbation cibles et les durees de rotation de recolte ou les periodes d'entree correspondantes, semble etre une methode realisable pour guider la foresterie ecologique dans toute region dotee d'un solide systeme de classification ecologique des terres et de multiples agents de perturbation. Mots-cles : perturbation naturelle, foresterie ecologique, durabilite, vegetation naturelle potentielle, classification ecologique des terres, planification du paysage., 1. Introduction Ecological forestry (also known as "ecosystem-based forestry") emphasizes the conservation of native biodiversity and ecological integrity (Christensen et al. 1996; Seymour and Hunter 1999). At the core of [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2015.08.008 Byline: James W.N. Steenberg, Andrew A. Millward, Peter N. Duinker, David J. Nowak, Pamela J. Robinson Abstract: Urban forests are now recognized as essential components of sustainable cities, but there remains uncertainty concerning how to stratify and classify urban landscapes into units of ecological significance at spatial scales appropriate for management. Ecosystem classification is an approach that entails quantifying the social and ecological processes that shape ecosystem conditions into logical and relatively homogeneous management units, making the potential for ecosystem-based decision support available to urban planners. The purpose of this study is to develop and propose a framework for urban forest ecosystem classification (UFEC). The multifactor framework integrates 12 ecosystem components that characterize the biophysical landscape, built environment, and human population. This framework is then applied at the neighbourhood scale in Toronto, Canada, using hierarchical cluster analysis. The analysis used 27 spatially-explicit variables to quantify the ecosystem components in Toronto. Twelve ecosystem classes were identified in this UFEC application. Across the ecosystem classes, tree canopy cover was positively related to economic wealth, especially income. However, education levels and homeownership were occasionally inconsistent with the expected positive relationship with canopy cover. Open green space and stocking had variable relationships with economic wealth and were more closely related to population density, building intensity, and land use. The UFEC can provide ecosystem-based information for greening initiatives, tree planting, and the maintenance of the existing canopy. Moreover, its use has the potential to inform the prioritization of limited municipal resources according to ecological conditions and to concerns of social equity in the access to nature and distribution of ecosystem service supply. Author Affiliation: (a) Environmental Applied Science and Management, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada (b) Urban Forest Research & Ecological Disturbance (UFRED) Group, Department of Geography and Environmental Studies, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada (c) School for Resource and Environmental Studies, Dalhousie University, 6100 University Avenue, Halifax, Nova Scotia, B3H 4R2, Canada (d) Northern Research Station, USDA Forest Service, 5 Moon Library, SUNY-ESF, Syracuse, NY, 13210, USA (e) School of Urban and Regional Planning, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada Article History: Received 1 April 2015; Revised 7 August 2015; Accepted 11 August 2015