Peter N. Duinker

The Significance of Environmental Impacts: an Exploration of the Concept

Since environmental impact assessment (EIA) is concerned primarily withsignificant environmental impacts, the concept of impact significance deserves to be defined and applied rigorously. In this article use of the term over the past 15 years in EIA documentation is reviewed. Some recent attempts at elucidating the concept are summarized. Four perspectives on impact significance that emerged from a series of workshops on the ecological basis for EIA are presented. These perspectives include (a) statistical (related to problems of isolating project-induced changes from natural variation), (b) ecological (related to the importance of project-induced changes from a purely ecological perspective), (c) social (related to the acceptability of project-induced changes in important environmental attributes), and (d) project (related to whether project-induced changes will indeed influence project decision making). The following synthesis is proposed: Any exercise in judging the significance of an environmental impact should thoroughly consider (a) the importance of the environmental attribute in question to project decision makers, (2) the distribution of change in time and space, (c) the magnitude of change, and (d) the reliability with which change has been predicted or measured. The implications of considering these factors are discussed.

Climate change and Canada's forests: From impacts to adaptation

T. B. Williamson, Natural Resources Canada, Canadian Forest Service S. J. Colombo, Ontario Ministry of Natural Resources P. N. Duinker, School for Resource and Environmental Studies, Dalhousie University P. A. Gray, Ontario Ministry of Natural Resources R. J. Hennessey, School for Resource and Environmental Studies, Dalhousie University D. Houle, Ministere des Ressources Naturelles et de la Faune du Quebec / Ouranos M. H. Johnston, Saskatchewan Research Council A. E. Ogden, Yukon Forest Management Branch D. L. Spittlehouse, British Columbia Ministry of Forests and Range

BIODIVERSITY CONSIDERATIONS IN CONSERVATION SYSTEM PLANNING: MAP-BASED APPROACH FOR NOVA SCOTIA, CANADA

Biodiversity considerations in conservation system planning include three main criteria: representation, special elements, and focal species. A GIS-based approach utilizing simple models was used to assess existing biophysical data relative to these criteria for conservation system planning in Nova Scotia, Canada, with potential utility in applications elsewhere. Representative samples of natural landscapes were identified on the basis of size (≥10 000 ha) and degree of naturalness (natural cover, uneven-aged forests, low or zero road density). Special elements were selected, including hotspots of diversity and rarity, critical habitat for species at risk, significant wetlands, old and unique forests, and ecosites. Habitat requirements of viable populations of focal species (American moose, American marten, and Northern Goshawk) were identified using species distribution data, habitat suitability, and population viability analyses. Priority core areas for biodiversity conservation system planning were ide...

A framework for assessing cumulative effects in watersheds: An introduction to Canadian case studies

From 2008 to 2013, a series of studies supported by the Canadian Water Network were conducted in Canadian watersheds in an effort to improve methods to assess cumulative effects. These studies fit under a common framework for watershed cumulative effects assessment (CEA). This article presents an introduction to the Special Series on Watershed CEA in IEAM including the framework and its impetus, a brief introduction to each of the articles in the series, challenges, and a path forward. The framework includes a regional water monitoring program that produces 3 core outputs: an accumulated state assessment, stressor-response relationships, and development of predictive cumulative effects scenario models. The framework considers core values, indicators, thresholds, and use of consistent terminology. It emphasizes that CEA requires 2 components, accumulated state quantification and predictive scenario forecasting. It recognizes both of these components must be supported by a regional, multiscale monitoring program.

Capturing Old-Growth Values for Use in Forest Decision-Making

Old-growth forests have declined significantly across the world. Decisions related to old growth are often mired in challenges of value diversity, conflict, data gaps, and resource pressures. This article describes old-growth values of citizens and groups in Nova Scotia, Canada, for integration in sustainable forest management (SFM) decision-making. The study is based on data from 76 research subjects who participated in nine field trips to forest stands. Research subjects were drawn from Aboriginal groups, environmental organizations, forestry professionals, and rural and urban publics. Diaries, group discussions, and rating sheets were used to elicit information during the field trips. Findings show that different elicitation techniques can influence the articulation of intensity with which some values are held. In addition, certain values are more often associated with old-growth than with other forest-age classes. Some values associated with old-growth are considered more important than others, and some silvicultural treatments are perceived to compromise old-growth values more than others. Demographic characteristics, such as constituency group, gender, and age, are shown to influence value priorities. Ideas on how to incorporate old-growth values into SFM decision-making are highlighted.

A proposal for further strengthening science in environmental impact assessment in Canada

We observe ongoing weaknesses in the quality of science underpinning environmental impact assessment (EIA) in Canada. This is frustrating because approaches for strong scientific practice in EIA were published decades ago. A major failing has been the lack of scientific support from outside the EIA practitioner community. We argue for a re-conception of science associated with EIA that includes a rigorous scholarship of application inside EIA and a vigorous scholarship of integration outside it. Cases of exemplary organizational structures and science applications in the Canadian forest sector are given. To turn EIA from the often bitter battleground of shallow impact debates to an enterprise of strong accumulation of effects knowledge, we urge the relevant communities of researchers and practitioners to become embedded communities of practice and reform the way science contributes to EIA.

Ecological integrity in urban forests

Ecological integrity has been an umbrella concept guiding ecosystem management for several decades. Though plenty of definitions of ecological integrity exist, the concept is best understood through related concepts, chiefly, ecosystem health, biodiversity, native species, stressors, resilience and self-maintenance. Discussions on how ecological integrity may be relevant to complex human-nature ecosystems, besides those set aside for conservation, are growing in number. In the case of urban forests, no significant effort has yet been made to address the holistic concept of ecological integrity for the urban forest system. Preliminary connections between goals such as increasing tree health, maintaining canopy cover, and reducing anthropogenic stressors and the general notion of integrity exist. However, other related concepts, such as increasing biodiversity, the planting of native species, and the full meaning of ecosystem health beyond merely tree health have not been addressed profoundly as contributors to urban forest integrity. Meanwhile, other concepts such as resilience to change and self-maintenance are not addressed explicitly. In this paper we reveal two camps of interpretation of ecological integrity for urban forests that in turn rely on a particular definition of the urban forest ecosystem and a set of urban forest values. Convergence and integration of these values is necessary to bring a constructive frame of interpretation of ecological integrity to guide urban forest management into the future.

A synthesis of survey results: The Extent of Forest Decline in Europe

During the last ten years, the concern about forest decline attributable to air pollutants has increased dramatically. In the early days of industrialization, symptoms of damage were evident on trees in the vicinity of smokestacks. However, the problem gained wide publicity only in the early 1980s when the first quantitative estimates of damage were made in some European countries. The estimates, based sometimes on expert judgment and sometimes on statistically valid surveys, were made with varying degrees of precision, and the definition of damage were different among countries. Only recently have surveys of the extent of forest damage throughout Europe been more consistently based on statistically sound measurements, so that it is now possible to collect and synthesize substantial quantities of data on the extent of the phenomenon of forest decline in Europe. The objectives of this article are: to summarize current data on the extent of forest decline for as many European countries as possible, to draw conclusions about the significance of forest decline in the context of forest resources and annual fellings of the countries, and to draw conclusions about the improved quality and consistency of data on the extent of forest decline.

Neighbourhood-scale urban forest ecosystem classification

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.

Forest Values: A Framework for Old-Growth Forest with Implications for Other Forest Conditions

Old-growth forests (OGF) in North America have declined significantly since European colonization. Many conflicts about basic values over OGF harvesting have occurred in recent decades. Understanding these values is an im- portant component of addressing such situations. This paper is based on two studies of OGF values, which captured the range of existing values and the nuances that define them. Moyer conducted a narrative study with six leaders in Canadas forest sector. Owen conducted a series of nine one-day field workshops which included 76 participants representing citi- zen constituency groups in Nova Scotia. Insight gained from these two studies was used to build upon existing forest val- ues typologies to construct a forest values framework with some unique features. The framework provides opportunities for immediate use and future research.