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Does Dust from Arctic Mines Affect Caribou Forage?

Journal of Environmental Protection 2017年第3期8卷 258-276页

作者： Wenjun Chen Sylvain G. Leblanc H. Peter White Christian Prevost Brian Milakovic Christine Rock Greg Sharam Harry O’Keefe Laura Corey Bruno Croft Anne Gunn Sjoerd van der Wielen Adeline Football Boyan Tracz Jody Snortland Pellissey John Boulanger canada Centre for Remote Sensing Natural Resources Canada Ottawa Canada ERM Environmental ressources Management Vancouver Canada Dominion Diamond Ekati Corporation Yellowknife Canada Environment and natural resources GNWT Yellowknife Canada Circum Arctic Rangifer Monitoring and Assessment Network Salt Spring Island Canada Tlicho Government Behchoko NT Canada Wek’èezhìi Renewable resources Board Yellowknife Canada Integrated Ecological Research Ltd. Nelson Canada

This study explores how dust from the Ekati Diamond Mine potentially affects the availability and quality of forage on the seasonal range of the Bathurst caribou herd. Understanding the effects of dust as a source of disturbance is important because the Bathurst caribou population has declined by 93% since the middle 1980s and there are reports that caribou in general may avoid mining projects. There are several challenges for quantifying dust impacts: 1) natural variations (e.g., topography, natural disturbance, and soil pH) may also impact forage availability and quality for caribou. To minimize their masking effect, we stratified survey sites into seven land cover classes and selected the most populous class (i.e., the dwarf shrub) for assessing the impact. 2) Within class variation (e.g., the proportion of area covered by rocks where vascular plants and lichen do not grow) can further skew the analysis. We eliminated this problem by examining only the area not covered by rocks. 3) Coarse and fine suspended particulates have different spatial coverages, chemical compositions, and pH values. Consequently, their impacts on caribou forage can be different. To distinguish their impacts, we sampled two areas: transects from the Misery Haul Road that has been in active use vs. those from a rarely used spur road outside the Misery Camp. We sampled percent vegetation cover, soil pH, and dust on leaves along these transects during the summers of 2015 and 2016. Our results indicated that the amount of dust on leaves in a zone of ~1000 m from the Misery Haul Road was 3 - 9 times than that of background sites. The zone of reduced lichen percent cover was also about 1000 m. In contrast, these road dust-induced changes in caribou forage were not observed for the dust-free transect from the spur road.

关键词： Mining Arctic Caribou Habitat Road Dust PM2.5 Vegetation Cover Lichen Soil pH Dust Deposition

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Have some landscapes in the eastern Canadian boreal forest moved beyond their natural range of variability?

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Forest Ecosystems 2018年第4期5卷 412-428页

作者： Pierre Grondin Sylvie Gauthier Veronique Poirier Patrice Tardif Yan Boucher Yves Bergeron Direction de la Recherche Forestiere Ministere des Foretsde la Faune et des Pares (MFFP)2700rue EinsteinQuebecQC GIP 3W8Canada ressources naturelles canada/natural resources canada Service Canadien des forets/Canadian Forest ServiceCentre de foresterie des Laurentides/Laurentian Forestry Center1055 rue du P.E.P.SQuebecQC G1V 4C7 Canada Institut de Recherche sur les Forets Universite du Quebec en Abitibi-Temiscamingue445boul.de I'UniversiteRouyn-NorandaQC J9X 5E4Canada Centre d'etude de la Foret Universite du QuebecMontreal CP 8888succ AMontrealQC H3C 3P8Canada

Background: In the contxt of ecosystem management, the present study aims to compare the natural and the present-day forested landscapes of a large territory in Quebec(canada). Using contemporary and long-term fire cycles, each natural forst landscape is defined according to the variability of its structure and composition, and compared to the present-day landscape. This analysis was conducted to address the question of whether human activities have moved these ecosystems outside the range of natural landscape ***: The study encompassed a forested area of 175 000 km2 divided into 14 landscapes. Using a framework that integrates fire cycles, age structure and forest dynamics, we characterized the forest composition and age structures that resulted from three historical fire cycles(110,140, and 180 years) representative of the boreal forest of eastern canada. The modeled natural landscapes were compared with present-day landscapes in regard to the proportion of old-growth forests(landscape level) and the proportion of late-successional forest stands(landscape level and potential vegetation type).Results: Four landscapes(39%) remain within their natural range of variability. In contrast, nine landscapes(54%)show a large gap between natural and present-day landscapes. These nine are located in the southern portion of the study area, and are mainly associated with Abies-Betula vegetation where human activities have contributed to a strong increase in the proportion of Populus tremuloides stands(early-successional stages) and a decrease of oldgrowth forest stands(more than 100 years old). A single landscape(7%), substantially changed from its potential natural state, is a candidate for adaptive-based ***: Comparison of corresponding natural(reference conditions) and present-day landscapes showed that ten landscapes reflecting an important shift in forest composition and age structure could be considered beyond the range of their natural v

关键词： Ecosystem management Reference conditions natural variability Resilience Fire cycle Age structure Forest dynamics Potential vegetation type Landscape ecology Theoretical natural landscape Present-day landscape

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Minto Large Igneous Province: A 2.00 Ga Mafic Magmatic Event in the Eastern Superior Craton Based on U-Pb Baddeleyite Geochronology and Paleomagnetism

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 69-70页

作者： Michael A.HAMILTON Jean GOUTIER Kenneth L.BUCHAN Jack Satterly Geochronology Lab Dept.of Earth Sciences University of Toronto Géologie Québec - Ministère de l'énergie et des ressources naturelles Geological Survey of canada

A precise U-Pb baddeleyite age of 1999±2 Ma has been obtained for the NNW trending Lac Shpogan dyke swarm of the James Bay area of the eastern Superior *** the age of the swarm was only

关键词： Pb A 2.00 Ga Mafic Magmatic Event in the Eastern Superior Craton Based on U-Pb Baddeleyite Geochronology and Paleomagnetism Minto Large Igneous Province Bay Ga

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Lichen-Spruce Woodland Early Indicators of Ecological Resilience Following Silvicultural Disturbances in Québec’s Closed-Crown Forest Zone

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American Journal of Plant Sciences 2013年第3期4卷 749-765页

作者： Esteban Gonzalez Francois Hébert Jean-Francois Boucher Pascal Sirois Daniel Lord Département des Sciences Fondamentales Université du Québec à ChicoutimiSaguenayCanada Direction de la Recherche Forestière Ministère des Ressources NaturellesQuébecCanada

Lichen woodlands (LW) located in the closed-crown boreal forest are not a successional stage moving towards a closed black spruce feathermoss stand (FM), but an alternative stable state, due to their previous forest history, and the occurrence of LWs located nearby closed-crown FM stands. Therefore, afforestation in those LWs through site preparation and plantation could shift back LW into FM stands. We implemented an experimental design with different combinations of silvicultural treatments in both site types (LW, FM). We monitored the evolution of plant diversity and the physiology of three bio-indicators (Picea mariana, Kalmia angustifolia, Rhododendron groenlandicum) in different microsites created by the silvicultural treatments. The return to the initial composition was noticed only two years after treatments, especially in the LW stands, thus indicating a higher level of early ecosystem resilience in LWs compared to FM stands. Mean species cover, especially in the FM stands, decreased the most in the skid trails created by logging, probably due to a lack of acclimation of bryophytes to open stand conditions. Conversely, ericaceous shrubs and lichens found in the LWs were already acclimated to open stand conditions, which give to LWs a restructuring advantage compared to FM plant communities after silvicultural treatments. Overall, FM and LW short-term resilience was similar, indicating equally efficient ecosystem reorganization in both stands. The comparable early resilience in managed LW and FM stands, in terms of plant biodiversity, contradicts the presumed fragility of LW stands, especially in this case where LWs are assumed to be an alternative stable state created by compound disturbances. Silvicultural treatments maintained the functional group diversity in LWs, a key element for ecosystem resilience. Therefore, this study support the idea that plantation following site preparation in LWs could be a valuable management strategy to reach several objecti

关键词： Afforestation Black Spruce Kalmia angustifolia Rhododendron groenlandicum Logging Picea mariana Vegetation Recovery Scarification Silviculture

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Ecosystem management in paludified boreal forests:enhancing wood production,biodiversity,and carbon sequestration at the landscape level

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Forest Ecosystems 2018年第4期5卷 376-389页

作者： Benoit Lafleur Nicole J.Fenton Martin Simard Alain Leduc David Paré Osvaldo Valeria Yves Bergeron NSERC-UQAT-UQAM Industrial Chair in Sustainable Forest Management and Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue445boul.de I'UniversiteRouyn-NorandaQC J9X 5E4Canada Department of Geography Laval UniversityQuebecQC GIV 0A6Canada Centre d'etude de la foret Universite du Quebec a Montreal141 Avenue du President-KennedyMontrealQC H2X IY4Canada ressources naturelles canada Service canadien des forets Centre de foresterie des Laurentides1055du P.E P S.P.O.13ox 3800QuebecQC GIV 4C7Canada

canada’s boreal forest represents an important contributor of the world’s wood supply industry. However,maintaining or increasing productivity of the boreal forest may be challenging in areas dominated by forested peatlands. Moreover, sustainable management of these forests must also consider other important aspects of the forest ecosystem such as biodiversity and carbon sequestration. To address these concerns, ecosystem-based management has been implemented in some Canadian jurisdictions, such as in regions where a large portion of the boreal forest is dominated by forested peatlands. The objectives of this paper are(1) to summarize our current understanding of how natural disturbances influence stand dynamics and biodiversity in forested peatlands, and(2) to review the main differences between natural and managed forest stands with respect to soil properties, stand productivity, understory plant communities. We also discuss how even-age management regime succeeds or fails to preserve old forests and how this loss affects both forest structure and habitat diversity at the landscape *** conclude by showing how, in boreal forested peatlands, forest management could contribute to carbon sequestration and mitigate projected climate change.

关键词： Clearcutting Fire Forest dynamics Partial cutting Soil properties Stand productivity Understory plant

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Water quality in forest and village ponds in Burkina Faso(western Africa)

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Journal of Forestry Research 2017年第5期28卷 1039-1048页

作者： Bilass Zongo Frdric Zongo Aboubacar Toguyeni Joseph I.Boussim Laboratoire de Biologie et Ecologie Vgtales Universit de Ouagadougou Unit de Recherche Aquaculture et Biodiversit Aquatique Laboratoire d'Etude et de Recherche sur les ressources naturelles et les Sciences Environnementales Universit Polytechnique de Bobo-Dioulasso

Forest ecosystems help conserve the quality of water resources in aquatic habitats. The conservation of biological diversity in aquatic and terrestrial ecosystems remains a communal concern. Aquatic ecosystems and resources are vulnerable but can be preserved and protected by forests. In sub-Saharan regions of Africa, water from ecosystems such as ponds still play important role in the livelihood of local populations. Water from temporary ponds is used by local populations for multiple needs; however, in this part of the world, the population is increasing, thus increasing human needs and activities and land use in the region. Land-use changes lead to deforestation, land degradation and the decline in freshwater, affecting human health and well-being. Forest degradation leads to the decline in ecosystem goods and services, particularly those related to watersheds. This study conducted in eastern Burkina Faso aimed to assess water quality of temporary ponds in protected forest areas (reserves) and surrounding villages. It was conducted in 61 temporary ponds where physical, chemical and biological variables were measured, such as water surface area, depth, transparency, macrophyte cover, pH, dissolved O2, conductivity, nutrient concentrations and algae biomass. The results showed that at p < 5%, water surface area (p = 0.02), depth (p = 0.00), nutrient content (p = 0.00), and algae biomass (p = 0.04) were significantly higher outside reserves than inside reserves. In contrast, macrophyte cover (mean cover percentages 53 vs. 44.5%) and water transparency (p = 0.02) were higher inside reserves. The variations in conductivity and pH were not significant. All trends showed the influences of human activities on water characteristics and the role forests and land cover had in preventing negative human impacts and disturbance of temporary ponds. Forests and land cover are important to water quality conservation and algae biomass regulation in temporary ponds. Prot

关键词： Ecosystem services Pond water Reserves Variables Western Africa

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Deformation induced decoupling between U-Pb and trace elements in titanite revealed through petrochronology and study of localized deformation

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Geoscience Frontiers 2023年第2期14卷 217-240页

作者： Charles Kavanagh-Lepage Félix Gervais Kyle Larson Riccardo Graziani Abdelali Moukhsil Département des génies civils géologiques et des minesPolytechnique MontréalMontréal H3T 1J4QuébecCanada Earth and Environmental Sciences IKBSASUniversity of British Columbia Okanagan3247 University WayKelownaBC V1V 1V7Canada natural resources canada Government of Canada601 Booth St.OttawaON K1A 0E8Canada Direction de l’acquisition des connaissances géoscientifiques Ministère de l’Énergie et des Ressources naturelles du Québec57004e Avenue Ouest QuébecQC G1H 6R1QuébecCanada

In this contribution,we analyzed a pair of mafic samples collected from a recently identified shear zone and its proximal footwall from the Manicouagan Imbricate Zone(MIZ)of the central Grenville Province,Québec,*** petrochronology,metamorphic phase equilibria modelling,trace element thermometry,and electron backscattered diffraction data were used to define a Pressure-Temperature-timeDeformation path for the two *** interconnected dislocation network within titanite grains,as outlined with Kerneled Average Misorientation maps,are spatially correlated with variation in the U-Pb system but not with that observed for trace element These results suggest that the U-Pb system was decoupled from trace and rare earth elements and that deformation,rather than interface-coupled dissolution-precipitation reactions or re-crystallisation,was the main driver for this *** addition to highlighting a potential pitfall of titanite petrochronology,our P-T-t-D path reveals that ductile shear zones were active later than previously suggested within the MIZ.

关键词： Titanite petrochronology U-Pb Geochronology Phase equilibria modelling Trace elements Deformation Decoupling

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Application of a Geomatics Approach for the Diachronic Study of the Meditterannean Coastline Case of Tangier Bay

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International Journal of Geosciences 2018年第6期9卷 320-336页

作者： Fatima Zahra Salim Mohammed Yassine El Habti Lech-Hab Khadija Ben Hamman Ahmed Raissouni Abdelkrim El Arrim Laboratoire "Environnement Océanologie et Ressources Naturelles" Dpt. des Sciences dela Terre FST de Tanger Km 9 Route de Ziatine Maroc

The coastline is one of the country’s most important environmental and economic resources. However, it is a delicate and highly coveted environ-ment on which many factors of evolution interact, both anthropogenic and natural. This work is concerned with the diachronic study of the coastline of the Mediterranean coast, particularly the coastal fringe at the level of Tangier Bay. In order to experimentally confirm the numerical models used and to take part in the development of an accurate, reliable and rapid decision support system for the assessment and remediation of the risks of accretion and coastal erosion, the methodology followed consists of the application of automatic analytical techniques, based on a geomatics approach, using a multi-temporal photo-interpretation, a Geographical Information System (GIS) and a computerized data analysis system (DSAS: Digital Shoreline Analysis System). The change rate will be calculated from the multi-date maps (1981-96 and 2017) using the End Point Rate (EPR). To achieve our objective, the study area was divided into three sectors from East to West: El Ghandouri Beach, Malabata Beach and the municipal square adjacent to the port. The GIS analysis of the data obtained shows that the coastline is present by location and for the three periods of comparison of the remarkable zones of erosion and sedimentation.

关键词： Mediterranean Coastline (SIG) Geographic Information System (DSAS) Digital Shoreline Analysis System Accretion Erosion

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Hydrological Study of Watersheds Arid and Semi-Arid South-Eastern Algeria (Chott Melghir, Chott El Hodna and Highlands Constantine)

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International Journal of Geosciences 2013年第10期4卷 1483-1490页

作者： Fares Belagoune Djamel Boutoutaou Laboratoire d’Exploitation et de Valorisation des ressources naturelles en Zones Arides Université d’Ouargla Ouargla Algeria Magister in Hydraulic Sciences University of Ouargla Ouargla Algeria

The objective of the study is to establish the hydrological characteristics, the hydrological behavior of river basins in arid and semi-arid south-eastern Algeria (establish of methodologies and necessary working tools for planning the development and management of water resources). The study on floods in Algeria is established by the National Agency of Water resources (ANRH shows that the country is confronted with the phenomenon of very destructive floods and floods especially in arid and semi-arid regions). Flooding of rivers in these areas is less known. They are characterized by their sudden duration (rain showers, thunderstorm). The duration of the flood is in the order of minutes to hours. The human and material damages caused by these floods are still high. The study area encompasses three watersheds in semi-arid, arid south and Algeria. There are pools of Chott-Melghir (68,751 km2), highland Constantine-07 (9578 km2) and El Hodna-05 basin (25,843 km2). The total area of this zone is about 104,500km2. Studies of protection against floods and design studies of hydraulic structures (spillway, storm basin, etc.) require the raw data which are often unknown in several places particularly at ungauged wadis of these areas.

关键词： Flood Watershed Specific Flow Coefficient of Variation Arid

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Phenotypic variation in food utilization in an outbreak insect herbivore

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Insect Science 2018年第3期25卷 467-474页

作者： Roberto Quezada-Garcia Alvaro Fuentealba Eric Bauce Faculté de Foresterie Géographie et Géomafique Département des Sciences du Bois et de la Forêt Centre d'Etude de la Forêt (CEF) Universite Laval Quebec City Quebec Canada

The effects of nutrition may have subtantial impact on insect evolution by shaping different components of phenotypes. The key to undestanding this evolutionary process is to know how nutritional condition affects additive and nonadditive components of the phenotype. However, this is poorly understood in outbreaking insects. We investigated the additive and nonadditive variation present in food utilization traits in spruce budworm individuals subjected to chronic nutritional stress. A total of 160 full-sib families of spruce budworm （Choristoneurafumiferana Clem.） were raised under laboratory condi- tions, feeding on 2 diets （high and low energy） during 3 generations. Variables tested were pupal mass, consumption rate （RCR）, growth rate （RGR）, approximate digestibility （AD）, the efficiency of conversion of digested food （ECD） and the efficiency of conversion of ingested food （ECI）. Our results show that all traits tested presented a high percentage of nonadditive effects that modulate phenotype expression. We found a significant impact of family × diet interaction on pupal mass, RGR and ECD. Furthermore, these traits exhib- ited the greatest heritability. There was no evidence of presence of maternal effects. The results revealed that food utilization traits may evolve through epigenetics effects, such as phenotypic plasticity. This information can be used by modellers to improve forecast of spruce budworm population dynamics.

关键词： food utilization nutritional stress phenotypic plasticity spruce budworm

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