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Subsistence harvesting and wild food production by Athabascan peoples is part of an integrated social-ecologi- cal system of interior Alaska. We describe effects of recent trends and future climate change projections on the boreal eco- system of interior Alaska and relate changes in ecosystem services to Athabascan subsistence. We focus primarily on moose, a keystone terrestrial subsistence resource of villages in that region. Although recent climate change has affected the boreal forest, moose, and Athabascan moose harvesting, a high dependence by village households on moose persists. An historical account of 20th century socioeconomic changes demonstrates that the vulnerability of Athabascan subsistence systems to climatic change has in some respects increased while at the same time has improved aspects of village resil- ience. In the face of future climate and socioeconomic changes, communities have limited but potentially effective mitiga- tion and adaptation opportunities. The extent to which residents can realize those opportunities depends on the responsiveness of formal and informal institutions to local needs. For example, increases in Alaska's urban population coupled with climate-induced habitat shifts may increase hunting conflicts in low-moose years. This problem could be mi- tigated through adaptive co-management strategies that project future moose densities and redirect urban hunters to areas of lower conflict. Resume´ : La recolte de subsistance et la production de nourriture sauvage par le peuple athapascan fait partie d'un sys- teme socio-ecologique integrede l'interieur de l'Alaska. Nous decrivons les effets des tendances recentes et des projec- tions de changements climatiques a venir sur l'ecosysteme boreal de l'interieur de l'Alaska et nous relions les changements dans les services de l'ecosysteme ala subsistance des athapascans. Nous mettons principalement l'accent sur l'orignal, une ressource terrestre de subsistance cledes villages de cette region. Bien que les changements climatiques re ´- cents aient affectela foret boreale, l'orignal et la recolte d'orignaux par les athapascans, les menages des villages conti- nuent adependre fortement de l'orignal. Un compte rendu historique des changements socioeconomiques survenus au 20 e siecle demontre que la vulnerabilitedes systemes de subsistances des athapascans aux changements climatiques a acer- tains egards augmentealors que des aspects de la resilience des villages se sont ameliores durant la meme periode. Face aux changements climatiques et socioeconomiques a venir, les communautes ont des possibilites d'adaptation et d'atte ´- nuation limitees mais potentiellement efficaces. Dans quelle mesure les residants peuvent concretiser ces possibilitesd e´- pend de la capacitede reaction des institutions formelles et informelles aux besoins locaux. Par exemples, des augmentations de la population urbaine de l'Alaska couplees a des changements d'habitat induits par le climat peuvent augmenter les conflits de chasse les annees durant lesquelles l'orignal est peu abondant. On pourrait attenuer ce probleme par des strategies de cogestion adaptative qui predisent la densitedes orignaux et redirigent les chasseurs urbains vers des zones moins conflictuelles. (Traduit par la Redaction)

In the boreal forests of interior Alaska, feedbacks that link forest soils, fire characteristics, and plant traits have supported stable cycles of forest succession for the past 6000 years. This high resilience of forest stands to fire disturbance is supported by two interrelated feedback cycles: (i) interactions among disturbance regime and plant-soil-microbial feed- backs that regulate soil organic layer thickness and the cycling of energy and materials, and (ii) interactions among soil conditions, plant regeneration traits, and plant effects on the environment that maintain stable cycles of forest community composition. Unusual fire events can disrupt these cycles and trigger a regime shift of forest stands from one stability do- main to another (e.g., from conifer to deciduous forest dominance). This may lead to abrupt shifts in forest cover in re- sponse to changing climate and fire regime, particularly at sites with intermediate levels of moisture availability where stand-scale feedback cycles are only weakly constrained by environmental conditions. However, the loss of resilience in individual stands may foster resilience at the landscape scale, if changes in the landscape configuration of forest cover types feedback to stabilize regional patterns of fire behavior and climate conditions. Resume´ : Dans la foret boreale de l'interieur de l'Alaska, les retroactions qui relient les sols forestiers, les caracteristiques des incendies et celles de la vegetation ont assurele maintien des cycles de succession forestiere pendant les 6000 dernie `- res annees. Cette grande resilience des peuplements forestiers face aux perturbations causees par le feu est le resultat de deux cycles interreliesd e retroactions : (i) les interactions entre le regime de perturbations et les retroactions entre les plantes, le sol et les microbes qui controlent l'epaisseur de l'horizon organique du sol et le recyclage de l'energie et des materiaux et (ii) les interactions entre les conditions du sol, les caracteristiques de la regeneration des plantes et les effets des plantes sur l'environnement qui maintiennent la stabilitedes cycles de composition des communautes forestieres. Les incendies inhabituels peuvent perturber ces cycles et declencher un changement de regime des peuplements forestiers d'un domaine de stabiliteaun autre (p. ex., d'une foret dominee par des coniferes aune foret dominee par des feuillus). Cela peut entraoˆner des changements abrupts dans le couvert forestier en reponse aux changements climatiques et a la modifica- tion du regime de feux, particulierement dans les stations avec un niveau intermediaire de disponibiliteen eau oules cy- cles de retroaction a l'echelle du peuplement sont assujettis seulement faiblement aux conditions environnementales. Cependant, la perte de resilience de peuplements particuliers peut favoriser la resilience a l'echelle du paysage si les chan- gements dans la configuration des types de couvert forestier al'echelle du paysage ont un effet de retroaction qui stabilise les patrons regionaux du comportement du feu et des conditions climatiques. (Traduit par la Redaction)

We review the observed and potential effects of climate change on native fauna of forests in northeastern North America by focusing on mammals, birds, amphibians, and insects. Our assessment is placed in the context of recent regional-scale climate projections. Climate change, particularly in recent decades, has affected the distribution and abundance of numerous wildlife species. Warming temperatures, alterations to precipitation regimes, seasonality, and climatic extremes are projected to affect species directly or indirectly in each of the focal taxa. Greatest climate change will occur during winter, and the survival of winter-active species as well as the survival, distribution, and abundance of hibernating mammals, amphibians, resident birds, and diapausing insects may be altered. Even under low emissions scenarios, effects on native fauna may be profound, affecting iconic species, endangered species, and species that provide economically valuable services, such as pollination and regulation of insect populations. However, much research that is essential to assessing the effects of climate change on the native fauna of northeastern forests remains to be done. Research that reveals causal mechanisms and relates these findings to population and community level processes will be most valuable.

We review twentieth century and projected twenty-first century changes in climatic and hydrologic conditions in the northeastern United States and the implications of these changes for forest ecosystems. Climate warming and increases in precipitation and associated changes in snow and hydrologic regimes have been observed over the last century, with the most pronounced changes occurring since 1970. Trends in specific climatic and hydrologic variables differ in their responses spatially (e.g., coastal vs. inland) and temporally (e.g., spring vs. summer). Trends can differ depending on the period of record analyzed, hinting at the role of decadal-scale climatic variation that is superimposed over the longer-term trend. Model predictions indicate that continued increases in temperature and precipitation across the northeastern United States can be expected over the next century. Ongoing increases in growing season length (earlier spring and later autumn) will most likely increase evapotranspiration and frequency of drought. In turn, an increase in the frequency of drought will likely increase the risk of fire and negatively impact forest productivity, maple syrup production, and the intensity of autumn foliage coloration. Climate and hydrologic changes could have profound effects on forest structure, composition, and ecological functioning in response to the changes discussed here and as described in related articles in this issue of the Journal.

Water cycles are changing because of human population growth and climate change. Such changes will affect fundamental system-level characteristics that in turn will greatly influence ecosystem form and functioning. Here, a collection of papers is offered that furthers our understanding of cause and effect relationships between altered hydrology and various ecosystem properties. Combined, these papers address issues related to inflows, connectivity, and circulation and vertical mixing. In regards to altered inflows, this collection of papers addresses how seagrass bed communities, incidence of some haptophyte harmful algal blooms, and biodiversity of intermittently flowing streams might respond. These papers also address factors that influence connectivity in wetlands, and in the case of a lake and its neighboring wetland, how connectivity between systems can profoundly affect ecosystem form and functioning. Finally, the effects of altered circulation and vertical mixing are addressed as they relate to the spread of some cyanobacteria blooms to higher latitudes. The reader of this collection of papers gains a better appreciation of how ecosystem form and functioning is influenced by hydrologic processes and can conclude that there is a need for continued research in this area to better understand the impacts of human population growth and climate change.

Climate change will create warmer temperatures, greater precipitation, and longer growing seasons in northern latitudes making agriculture increasingly possible in boreal regions. To assess the potential of any such expansion, this paper provides a first-order approximation of how much land could become suitable for four staple crops (corn, potato, soy, and wheat) in Canada by 2080. In addition, we estimate how the environmental trade-offs of northern agricultural expansion will impact critical ecosystem services. Primarily, we evaluate how the regulatory ecosystem services of carbon storage and sequestration and the habitat services supporting biodiversity would be traded for the provisioning services of food production. Here we show that under climate change projected by Canadian Earth System Model (CanESM2) Representative Concentration Pathway 4.5, ∼1.85 million km2of land may become suitable for farming in Canada’s North, which, if utilized, would lead to the release of ∼15 gigatonnes of carbon if all forests and wetlands are cleared and plowed. These land-use changes would also have profound implications for Indigenous sovereignty and the governance of protected and conserved areas in Canada. These results highlight that research is urgently needed so that stakeholders can become aware of the scope of potential economic opportunities, cultural issues, and environmental trade-offs required for agricultural sustainability in Canada.

Subsistence is the basis for food access for Inuvialuit in the western Canadian Arctic and has strong economic, dietary, and cultural importance. Inuvialuit harvest beluga whale (Delphinapterus leucas (Pallas, 1776)) from the eastern Beaufort beluga population during summer months within parameters established through co-management. Over the past thirty years there has been a dramatic decline in the number of beluga harvested by Inuvialuit from the community of Aklavik, Northwest Territories. This paper investigates the potential drivers of change, both social and ecological, affecting the beluga harvest. Data were collected using 32 semi-directed interviews and experiential learning. Results revealed that ecological changes, notably coastal erosion at preferred whaling camps and unpredictable and severe weather have made harvesting more difficult, expensive, and often impractical. These changes are being experienced together with social changes including the loss of elders and their knowledge, and changing values and motivations for harvesting beluga. We conclude that no one driver is responsible for the decline in the beluga harvest, but rather it is the result of multiple social-ecological changes operating across scales that affect the feasibility of the harvest and motivation to participate. Isumatuyut ikayuqtuat avvakuyaa niqimun pimagaa Inuvialuit uataani Canadian Arcticmi nakuuyuq manik, niqilu, inuusiq nakuruallaktuaq. Inuvialuit katitait qilalugaq (Delphinapterus leucas (Pallas, 1776)) kivanmun Beaufort qilalugaq suli auyaqmi savaktiit. Sivulliqmi inuinnaq-qulit ukiuqmi mikliyuat tapqua qilalugaq katitait Inuvialuit Aklavik, Northwest Territoriesmi. Una makpiraaq ilisaqtuat anguniaqtuat, iluqatik inuuniarvikmi imaqmilu, tutqaanaittuq qilalugaq katitait. Kisitchiun katitait atugaa inuinnaq-qulit-malruknik apiqsiyuat asulu ilisaqtuat. Taimaagaa takupkagaa imaqmilu allauyuaq, taamna sallirq maqaigaa nuna taamna qilalugaqmun tanmaaq asulu allauyuaq silakluk asiin katitait tutqaanaittuq, akituyuqlu tutqaanaittuq. Taamna allauyuat illisaktuat atautchikun inuuniarvik ila tuquyuat innait asulu ilisimaruat, allauyuat pitqusiqlu ikayuqtuaq katitait qilalugaq. Uvagut taimagaa anguniaqti mikliyuat qilalugaq katitait taimagaa inugiaktut inuuniarvikmi imaqmilu allauyuaq savaktuat tutqaanaittuq asulu katitait ikayuqtuat ila taputiyaa.

Climate change and food security are complex global issues that require multidisciplinary approaches to resolve. A nexus exists between both issues, especially in developing countries, but little prior research has successfully bridged the divide. Existing resolutions to climate change and food security are expensive and resource demanding. Climate modelling is at the forefront of climate change literature and development planning, whereas agronomy research is leading food security plans. The Benin Republic and Nigeria have grown and developed in recent years but may not have all the tools required to implement and sustain long-term food security in the face of climate change. The objective of this paper is to describe the development and outputs of a new model that bridges climate change and food security. Data from the Intergovernmental Panel on Climate Change’s 5th Regional Assessment (IPCC AR5) were combined with a biodiversity database to develop the model to derive these outputs. The model was used to demonstrate what potential impacts climate change will have on the regional food security by incorporating agronomic data from four local underutilized indigenous vegetables (Amaranthus cruentus L., Solanum macrocarpon L., Telfairia occidentalis Hook f., and Ocimum gratissimum L.). The model shows that, by 2099, there is significant uncertainty within the optimal recommendations that originated from the MicroVeg project. This suggests that MicroVeg will not have long-term success for food security unless additional options (e.g., new field trials, shifts in vegetable grown) are considered, creating the need for need for more dissemination tools.

Recent studies reporting shifts in the timing of salmonid migrations have suggested global warming to be a cause. However, the specific mechanisms underlining the evolution of earlier migration timing in salmonid fishes are unknown. In this paper, I present a hypothesis by which fishery-induced selection works to advance the timing of salmonid migration, given that the timings of migration and breeding are genetically controlled heritable traits. Although late-spawning salmon brood lines enter rivers after early-spawning brood lines, there is evidence that all brood lines arrive in coastal fishing grounds at similar times. As such, late-spawning brood lines would be fished for longer periods of time, with their increased harvest rate imposing directional selection on earlier-spawning brood lines. Thus, fisheries-induced evolution could favor the earlier timing of river entry to escape coastal fisheries. Should earlier migration timing not be an adaptation to global warming — should it be a maladaptation to fisheries-induced selection instead — then it will have a negative impact on the sustainability of salmonid resources.

In commenting on our review about barriers to climate change adaptation and mitigation (Williamson and Nelson 2017, Can. J. For Res. 47(12): 1567–1576, doi: 10.1139/cjfr-2017-0252 ), Wellstead et al. (2018, Can. J. For. Res. 48(10), doi: 10.1139/cjfr-2017-0465 ) argue that the “functionalist assumptions” underlying barriers analysis in general and our paper in particular are problematic. They also argue that barriers analysis — a method widely employed both in scholarly climate change adaptation research and in national and international climate change assessments — should be replaced by approaches that remain untested in the context of climate change adaptation research, particularly in forestry adaptation and mitigation research. We believe that neither the scholarly research on adaptation and mitigation barriers nor our review have characteristics of functionalism or imply functionalist assumptions. Moreover, we disagree that barriers analysis can be replaced by the methodologies that they propose because these latter approaches address different aspects and features of processes supporting movement toward comprehensive and integrated adaptation and mitigation in forest management. We do agree that there are knowledge gaps relative to examinations and explanations of causal mechanisms to explain decision-making and policy process outcomes that have already occurred, and we encourage research to address these gaps. Ultimately, this aspect of social science research is complementary to, not a substitute for, barriers research.

This paper documents Inuvialuit traditional ecological knowledge of beluga, including ecology and behavior, hunting techniques, and food preparation under changing climatic conditions in Tuktoyaktuk, NT. Beluga whale (Delphinapterus leucas) is an important food source for Inuvialuit in the western Canadian Arctic, a region that is experiencing dramatic climate change. Data were collected using semi-directed interviews with 17 Inuvialuit beluga harvesters and participant observation. The research found that Inuvialuit beluga harvesters possess detailed rational knowledge of beluga, particularly regarding hunting techniques and food preparation, both which are guided by a moral code about how to behave with respect to beluga. In terms of beluga ecology and behavior, Inuvialuit knowledge is limited to anecdotal reasoning drawing on generalized observations of beluga and the accounts of others. Inuvialuit are experiencing the effects of climate change, but seem to be coping thus far in the context of beluga harvesting but ongoing change in the region may increase the risks associated with hunting and preparing beluga in the future.

This paper identifies and characterizes current knowledge on climate change impacts, adaptation, and vulnerability for Canada’s northern coastline, outlining key research gaps. Warming temperatures and increased precipitation have been documented across the northern coast, with the rate of sea ice decline ranging from 2.9% to 10.4% per decade. Storm intensity and frequency is increasing, and permafrost is warming across the region. Many of these changes are projected to accelerate in the future, with in excess of 8 °C warming in winter possible under a high-emission scenario by 2081–2100. Vulnerability to these changes differs by region and community, a function of geographic location, nature of climate change impacts, and human factors. Capacity to manage climate change is high in some sectors, such as subsistence harvesting, but is being undermined by long-term societal changes. In other sectors, such as infrastructure and transportation, limitations in climate risk management capacity result in continuing high vulnerabilities. There is evidence that adaptation is taking place in response to experienced and projected impacts, although readiness for adaptation is challenged by limited resources, institutional capacity, and a need for support for adaptation across levels of government. Priority areas for future research include (i) expanding the sectoral and geographic focus of understanding on climate change impacts, adaptation, and vulnerability; (ii) integrating climatic and socio-economic projections into vulnerability and adaptation assessments; (iii) developing an evidence base on adaptation options; and (iv) monitoring and evaluating the effectiveness of adaptation support. Cross-cutting themes for advancing climate change impacts, adaptation, and vulnerability research on the north coast more broadly include the need for greater emphasis on interdisciplinary approaches and cross-cultural collaborations, support for decision-orientated research, and focus on effective knowledge mobilization.

Mexican temperate forests, at the southernmost end of the distribution range of this ecosystem, are the world’s centre of diversity of pine and oak, with 55 and 161 species, respectively. Such forests are threatened by land-use change, unsustainable forest management practices, and climate change; these threats reduce their diversity, alter the distribution ranges of species, modify disturbance regimes, and reduce ecosystem adaptability. This paper briefly reviews (i) the ecology of the Mexican temperate forests, (ii) the ecological basis for the unique diversity of pine and oak species, (iii) the main disturbances as well as the main drivers of global changes affecting these forests, in particular climate change, and (iv) the social, economic, and cultural factors to be considered in proposing a new forest management approach. It proposes a new conceptual framework to manage Mexican temperate forests that are in line with (i) their natural dynamics, (ii) the rapidly changing and uncertain global environmental, social, and economic conditions, and (iii) the complex adaptive system approach. This new forest management combines functional zoning, multispecies plantations, and sylvicultural interventions to increase the adaptive capacity of forests as a way to balance the increasing need for timber products with the need for other ecosystem services facing rapidly changing and uncertain future environmental, social, and economic conditions.

The ice conditions in a regulated river will depend on the climatic changes as well as the changes to the hydropower operation strategies in the future. The existing literature shows that very few studies have been carried out to investigate the impact of climate change on the river ice regime, which is important for operation of hydropower in cold climates. In this study, a series of modelling tools have been used to transform the climate change signal in terms of precipitation and air temperature into cross-section based river ice assessment in a basin with a complicated hydropower system. The study is based on the EURO-CORDEX climate change data extracted from a regional climate model driven by a suite of five general circulation models with three representative concentration pathways. Hydrological model simulation results show that the winter and spring flow will be increased, which will have an impact on the river ice conditions towards the middle and end of this century. Reservoir-hydropower model simulation shows that the production flows in the winter will be increased in the future. River ice model simulation shows the number of days with freezing water temperature are reduced in the future climate, and correspondingly days with frazil ice are reduced at most of the locations in the study area. The future period with ice cover will also be shortened. The paper also demonstrates a general methodology and procedure to simulate future ice conditions in a regulated river combining multiple models and data sets.

Analyses of climate change and the forest sector have identified the importance of individual actors, institutions, and organizations within communities for effective adaption and climate mitigation. Yet, there remains little recognition of how the internal dynamics of these institutions and organizations are influenced by gender and other social considerations such as age and culture. Research from developing countries and cognate resource sectors suggests that these considerations are critical for enhancing local adaptive capacity. Despite extensive review of forestry research across North America and western Europe, we found almost no research that addresses how differential social capabilities within forest-based communities affect adaptation to climate change. In this paper, we document the potential that gender sensitivity might provide to conceptions and practical applications of adaptive capacity and identify four types of research opportunities to address this gap: (i) developing disaggregated capitals frameworks; (ii) creating inclusive models; (iii) informing social planning; and (iv) understanding gender mainstreaming. Research focused on these opportunities, among others, will provide more robust theoretical understanding of adaptive capacity and strategic interventions necessary for effective adaptation.

Climate change is affecting Canada’s boreal zone, which includes most of the country’s managed forests. The impacts of climate change in this zone are expected to be pervasive and will require adaptation of Canada’s forest management system. This paper reviews potential climate change adaptation actions and strategies for the forest management system, considering current and projected climate change impacts and their related vulnerabilities. These impacts and vulnerabilities include regional increases in disturbance rates, regional changes in forest productivity, increased variability in timber supply, decreased socioeconomic resilience, and increased severity of safety and health issues for forest communities. Potential climate change adaptation actions of the forest management system are categorized as those that reduce nonclimatic stressors, those that reduce sensitivity to climate change, or those that maintain or enhance adaptive capacity in the biophysical and human subsystems of the forest management system. Efficient adaptation of the forest management system will revolve around the inclusion of risk management in planning processes, the selection of robust, diversified, and no-regret adaptation actions, and the adoption of an adaptive management framework. Monitoring is highlighted as a no-regret action that is central to the implementation of adaptive forest management.

Hazards related to climate change (e.g., intensified storms, coastal flooding associated with sea level rise) are globally pervasive yet geographically-specific problems that demand societal response. Unfortunately, studies have shown that people are often unaware of (or inaccurately perceive) the true risk, thereby limiting their motivation to take steps to lower their vulnerability. Visualization of the anticipated impacts (either spatially or non-spatially) has an important role to play in risk communication, potentially avoiding peoples’ cognitive biases, helping to focus their attention, and allowing them to personally evaluate the evidence. In this paper, key findings of the risk perception literature are presented and a conceptual framework provided to help guide: (1) the identification of important information requirements (anticipating the influence of psychological effects); (2) the selection and design of visualizations; and (3) the assessment of the effectiveness of visualizations for enhancing perception of risk and inspiring a public willingness to adapt. A case study involving coastal flooding in South-East New Brunswick is referred to throughout.

The availability of water resources in southern Alberta is under pressure, now and most likely even more so in the remainder of the 21st century if forecasts on climate change, economic development and associated population growth come true. Alberta Environment is mandated by the provincial Water Act to regulate most use of water through a system of water licenses. This department is currently using a water resource management model (WRMM) to support its planning, but wishes to expand the reach of its decision support tools by including additional factors such as the land-use dynamics. This paper presents the coupling of the WRMM and a land-use cellular automata (CA) model to constrain land development based on water availability in the Elbow River watershed in southern Alberta. Simulations were run with a calibrated CA model using a land-use map of 2006 as the starting year up to the year 2031, at a five-year interval and at a spatial resolution of 60 m. Two scenarios were tested: the business as usual scenario, which is a simple extrapolation of observed historical land development, expressed as the number of built-up cells, and a second scenario in which land development is constrained based on the WRMM water availability output. Results indicate that land development varies in terms of growth and spatial distribution when comparing the two scenarios. The potential benefits and limitations of the two models are discussed and further improvement needed to increase their usefulness in guiding water resource management is highlighted.

The main objective of this paper is to evaluate whether future climate change would trigger an increase in the fire activity of the Waswanipi area, central Quebec. First, we used regression analyses to model the historical (1973-2002) link between weather conditions and fire activity. Then, we calculated Fire Weather Index system components using 1961-2100 daily weather variables from the Canadian Regional Climate Model for the A2 climate change scenario. We tested linear trends in 1961-2100 fire activity and calculated rates of change in fire activity between 1975-2005, 2030- 2060, and 2070-2100. Our results suggest that the August fire risk would double (+110%) for 2100, while the May fire risk would slightly decrease (-20%), moving the fire season peak later in the season. Future climate change would trigger weather conditions more favourable to forest fires and a slight increase in regional fire activity (+7%). While considering this long-term increase, interannual variations of fire activity remain a major challenge for the development of sustainable forest management. Resume´ : Le principal objectif de cet article est d'evaluer si les changements climatiques futurs vont conduire a une aug- mentation de l'activitedes feux dans la region de Waswanipi, dans le centre du Quebec. Tout d'abord, nous avons utilise ´ des regressions lineaires pour modeliser la relation historique (1973-2002) entre les conditions meteorologiques et l'ac- tivitedes feux. Ensuite, nous avons calculeles composantes du systeme de l'Indice Fore ˆ-Meteoapartir des simulations quotidiennes des conditions meteorologiques du Modele Regional Canadien du Climat pour le scenario A2 de changements climatiques (1961-2100). Nous avons testeles tendances lineaires de l'activitedes feux sur la periode 1961-2100, et cal- culeles taux de changement entre 1975-2005, 2030-2060, et 2070-2100. Nos resultats suggerent que le risque de feu du mois d'aout pourrait doubler (+110 %) d'ici 2100 alors que celui du mois de mai pourrait diminuer (-20 %). Ainsi, le pic saisonnier de l'activitedes feux pourrait survenir plus tard dans la saison. Les changements climatiques futurs pourraient egalement creer des conditions plus favorables aux incendies forestiers, et donc aune legere augmentation de l'activitere ´- gionale des feux (+7 %). Bien que nos resultats suggerent une augmentation along terme de l'activitedes feux, la variabi- liteinterannuelle des feux demeure un defi important pour le developpement d'un amenagement forestier durable.

Soil ecology science has contributed a rich understanding of natural soil patterns and processes, and played a role in revolutionizing the management of ecosystems. This basic understanding is also providing a foundation for predicting and managing the consequences of climate change on ecosystems, including their resilience to disturbance, biotic diversity, and carbon and nutrient dynamics. To help address the challenges of climate change, future soil ecology research and management would benefit from a complex systems approach, where network and dynamics systems theory are used to predict plant community and ecosystem responses to disturbance. A reductionist approach to management that ignores networks and system dynamics, by contrast, is destined to contribute to ecological degradation as climate changes. In this paper, I describe mycorrhizal networks as models of biological networks in the interior Douglas-fir forests of British Columbia, and the role they play in carbon flux and regeneration dynamics following disturbance. I propose a conservationist approach for managing forest mycorrhizal networks and hub trees that can facilitate native plant migrations, limit exotic plant invasions, and bolster ecological resilience. Interdisciplinary research that integrates the dynamics of multiple, overlapping networks will help develop management practices that sustain ecosystems in our changing climate. Key words: Climate change, complex systems, mycorrhizal networks, species migrations

A comprehensive review of Holocene paleoenvironmental data has been prepared, providing the basis for evaluating natural variability in climate and ecosystem dynamics in the northern Columbia River basin. The paleoenvironmental record reveals four major climatic shifts and a number of less well-defined climatic changes throughout the Holocene. The major climate changes are (1) a cool or cold, late-glacial climate at the end of the last glaciation (>11 500 cal. year BP), (2) an interval of drought and maximum summer warmth during the early Holocene (ca. 10500 to 8000 cal. year BP), (3) a mid-Holocene trend towards a cooler, more moist climate (ca. 8000 to ca. 4000 cal. year BP), and (4) a relatively stable climate persisting from ca. 4000 cal. year BP until the arrival of European settlers. Air temperatures have warmed by about 1 °C over the past century. Minor climate events that are emerging as global in nature include Little Ice Age (1200–150 BP) conditions, and a late Holocene cool wet period (3500–2500 BP). These are observed in some study sites examined in this paper and may be related to large-scale cycles of 2800–2000 and 1500 years. A discussion of changing atmospheric circulation patterns, and the causes of long-term climatic change are included, together with a discussion of the implications of the paleoenvironmental record for understanding future climate, and the likely response of communities and ecosystems.

The northern fulmar Fulmarus glacialis is a ubiquitous seabird found across the North Atlantic Ocean and into the Canadian Arctic. However, we know little of its ecology in the Arctic, which is unfortunate, because it possesses many traits that make it an excellent biomonitor of the condition of Arctic marine environments. Presently, Arctic fulmars face threats from harvest, bycatch in fisheries, and fouling in oil spills while the birds are in their winter range (the North Atlantic). However, during breeding, migration, and overwintering, they may also experience stress from ecotourism, contaminants, particulate garbage, and climate change. In this paper I review the effects of all of these threats on fulmars and I describe how the ecology of these birds makes them particularly suitable for tracking contaminants, garbage, and the effects of climate change in the Arctic marine ecosystem. I also highlight our key existing knowledge gaps on this species and how additional research will strengthen the utility of fulmars as biomonitors. Key words: northern fulmar, Fulmarus glacialis, Arctic, contaminants, climate change, pollution.

Understanding species–habitat associations is critical for designing marine reserves, defining essential fish habitat, and predicting the impacts of climate change on fisheries. For many species, however, there is a paucity of fisheries-independent data that simultaneously track abundance and environmental variables, as is the case for widow rockfish (Sebastes entomelas), a commercially important fishery off the west coast of the United States. In this paper, I generalize a previous approach to identifying habitat associations so that fisheries-dependent data can be used. In analyzing Oregon commercial logbook records and archived environmental data from the National Oceanographic Data Center, I found three environmental variables (bottom depth, vertical depth of fish in the water column, and temperature) to be statistically adequate. Using a generalized Kolmogorov–Smirnov test statistic, I compared an empirically derived cumulative distribution function (CDF) of the habitat sampled to a CDF weighted by widow rockfish catch. Results suggest that the significant habitat association for widow rockfish includes bottom depths between 136 and 298 m, vertical depths between 101 and 197 m, and temperatures between 7.1 and 8.1°C. This novel use of commercial logbook data, which links disparate data sources and explicitly accounts for unequal spatial sampling, is a methodological advance that also provides initial insights into widow rockfish habitat preferences.

This paper examines the impact that climatic change over the last millennium has had on aggradation and degradation of permafrost peatlands and the associated change in organic matter accumulation. Permafrost reached its southernmost Holocene extent in boreal continental western Canada during the Little Ice Age with 28 800 km2 of permafrost peatland present within a sensitive zone demarcated by permafrost degradation. Subsequent degradation of permafrost has occurred in response to warming, with forested bogs changing to nonforested poor fens, associated with rising water levels. In conjunction with this ecosystem change, long-term net organic matter accumulation increases. As permafrost is in disequilibrium with climate, much of the permafrost that remains is in a relict state. Mapping of past and present permafrost distribution from peatland landforms indicates only 9% has degraded since the Little Ice Age, resulting in a 5% increase in long-term net organic matter accumulation. Of the permafrost that remains, 22% is in disequilibrium, located largely in the northern part of the sensitive zone. Additional loss of forested lands will occur in the future in boreal continental western Canada under present-day climatic conditions as permafrost approaches equilibrium, with a further 11% increase in long-term net organic matter accumulation predicted.