Pub Date : 2021-10-02DOI: 10.1080/11956860.2021.1987738
N. Bhiry, M. Bernier, N. Lecomte, R. Fortier, J. Woollett
Centre d’études nordiques (CEN) and Département de géographie, Université Laval, Québec, Québec, Canada; Centre d’études nordiques (CEN) and Centre Eau, Terre, Environnement, Institut national de la recherche scientifique, Québec, Québec, Canada; Centre d’études nordiques (CEN) and Canada Research Chair in Polar and Boreal Ecology, Department of Biology, Université de Moncton, Moncton, Nouveau Brunswick, Canada; Centre d’études nordiques (CEN) and Département de géologie et génie géologique, Université Laval, Québec, Québec, Canada; Centre d’études nordiques (CEN) and Département des sciences historiques, Université Laval, Québec, Québec, Canada
{"title":"The Centre D'études Nordiques (CEN): Challenges and Perspectives of Research on Nordicity in Partnership with Indigenous Communities","authors":"N. Bhiry, M. Bernier, N. Lecomte, R. Fortier, J. Woollett","doi":"10.1080/11956860.2021.1987738","DOIUrl":"https://doi.org/10.1080/11956860.2021.1987738","url":null,"abstract":"Centre d’études nordiques (CEN) and Département de géographie, Université Laval, Québec, Québec, Canada; Centre d’études nordiques (CEN) and Centre Eau, Terre, Environnement, Institut national de la recherche scientifique, Québec, Québec, Canada; Centre d’études nordiques (CEN) and Canada Research Chair in Polar and Boreal Ecology, Department of Biology, Université de Moncton, Moncton, Nouveau Brunswick, Canada; Centre d’études nordiques (CEN) and Département de géologie et génie géologique, Université Laval, Québec, Québec, Canada; Centre d’études nordiques (CEN) and Département des sciences historiques, Université Laval, Québec, Québec, Canada","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"28 1","pages":"199 - 215"},"PeriodicalIF":1.3,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49209364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-15DOI: 10.1080/11956860.2021.1969790
C. Touati, T. Ratsimbazafy, J. Poulin, M. Bernier, Saeid Homayouni, R. Ludwig
ABSTRACT We investigated the sensitivity to vegetation cover type of active (PALSAR) and passive (SMAP) freeze/thaw (F/T) classification. We also used F/T classification from high-resolution PALSAR data (30 m) to follow the evolution of frozen and thawed soil states obtained from an adaptive algorithm with low-resolution SMAP data (36 km). We used PALSAR and SMAP scenes acquired from June 2015 to January 2017 over the Tursujuq National Park (Umiujaq, Quebec, Canada). A new F/T algorithm with a specific reference threshold under each vegetation type (shrub, grass, lichen, wetland, and bare land) is proposed to classify PALSAR pixels. The validation of the PALSAR F/T classification with soil temperature at ∼5 cm depth revealed a greater overall accuracy (> 80%), with horizontal transmitted and vertical received (HV) thresholds. The PALSAR F/T classification shows that a SMAP pixel is classified as frozen when more than 50% of its area is frozen at the surface. We confirmed the sensitivity to vegetation cover type of passive and active F/T classification with L-band sensor.
{"title":"Landscape Freeze/Thaw Mapping from Active and Passive Microwave Earth Observations Over the Tursujuq National Park, Quebec, Canada","authors":"C. Touati, T. Ratsimbazafy, J. Poulin, M. Bernier, Saeid Homayouni, R. Ludwig","doi":"10.1080/11956860.2021.1969790","DOIUrl":"https://doi.org/10.1080/11956860.2021.1969790","url":null,"abstract":"ABSTRACT We investigated the sensitivity to vegetation cover type of active (PALSAR) and passive (SMAP) freeze/thaw (F/T) classification. We also used F/T classification from high-resolution PALSAR data (30 m) to follow the evolution of frozen and thawed soil states obtained from an adaptive algorithm with low-resolution SMAP data (36 km). We used PALSAR and SMAP scenes acquired from June 2015 to January 2017 over the Tursujuq National Park (Umiujaq, Quebec, Canada). A new F/T algorithm with a specific reference threshold under each vegetation type (shrub, grass, lichen, wetland, and bare land) is proposed to classify PALSAR pixels. The validation of the PALSAR F/T classification with soil temperature at ∼5 cm depth revealed a greater overall accuracy (> 80%), with horizontal transmitted and vertical received (HV) thresholds. The PALSAR F/T classification shows that a SMAP pixel is classified as frozen when more than 50% of its area is frozen at the surface. We confirmed the sensitivity to vegetation cover type of passive and active F/T classification with L-band sensor.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"28 1","pages":"421 - 433"},"PeriodicalIF":1.3,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47653998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-07DOI: 10.1080/11956860.2021.1969825
Jordan A. McNamara, J. Schaefer, G. Bastille‐Rousseau, S. Mahoney
ABSTRACT Landscapes can influence the distribution of harvesting by influencing animal distribution and hunter access. For species like caribou, Rangifer tarandus, decades-long shifts in abundance and distribution might alter such relationships, but few studies have been conducted at such scales. We examined relationships between landscape features and 21,380 harvest records of migratory caribou in Newfoundland during caribou population growth (1980s), cessation of growth (1990s), and decline (2000s). We focused on features hypothesized to influence the distributions of caribou and hunters: lichen landcover, roads, cutblocks, outfitter camps, power lines, and towns. We uncovered larger harvests by resident hunters of male and female caribou among lichen landcover, likely providing preferred caribou forage, and larger harvests by non-resident hunters of male caribou away from towns, reflecting the locations of outfitter camps. Only during later decades, resident harvests occurred nearer power lines and cutblocks, likely providing hunter access and reflecting risk-prone foraging by caribou. We surmise that the harvest was facilitated by open habitats, preferred by caribou, and anthropogenic features leading to hunter access, especially as the caribou population declined. Such knowledge at broad scales is increasingly important in an era of widespread disruption to landscapes.
{"title":"Landscape Features and Caribou Harvesting during Three Decades in Newfoundland","authors":"Jordan A. McNamara, J. Schaefer, G. Bastille‐Rousseau, S. Mahoney","doi":"10.1080/11956860.2021.1969825","DOIUrl":"https://doi.org/10.1080/11956860.2021.1969825","url":null,"abstract":"ABSTRACT Landscapes can influence the distribution of harvesting by influencing animal distribution and hunter access. For species like caribou, Rangifer tarandus, decades-long shifts in abundance and distribution might alter such relationships, but few studies have been conducted at such scales. We examined relationships between landscape features and 21,380 harvest records of migratory caribou in Newfoundland during caribou population growth (1980s), cessation of growth (1990s), and decline (2000s). We focused on features hypothesized to influence the distributions of caribou and hunters: lichen landcover, roads, cutblocks, outfitter camps, power lines, and towns. We uncovered larger harvests by resident hunters of male and female caribou among lichen landcover, likely providing preferred caribou forage, and larger harvests by non-resident hunters of male caribou away from towns, reflecting the locations of outfitter camps. Only during later decades, resident harvests occurred nearer power lines and cutblocks, likely providing hunter access and reflecting risk-prone foraging by caribou. We surmise that the harvest was facilitated by open habitats, preferred by caribou, and anthropogenic features leading to hunter access, especially as the caribou population declined. Such knowledge at broad scales is increasingly important in an era of widespread disruption to landscapes.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"29 1","pages":"39 - 53"},"PeriodicalIF":1.3,"publicationDate":"2021-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41930542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-27DOI: 10.1080/11956860.2021.1949821
Alex Setchell, Sean R. Haughian
ABSTRACT Species distribution models are powerful tools on their own for the management of rare and at-risk species, but their utility as such can be limited if their accuracy is low, or if management policies are applied without consideration of the structure of the data. We tested the accuracy of a MaxEnt species distribution model for white-rimmed shingle lichen (Fuscopannaria leucosticta) in New Brunswick, Canada, and proposed an additional decision support-tool that matches the species probability of occurrence (PO) to possible management actions. The model was tested using two years of new field observations. Classification trees were used to define four groups across the range of PO values. Chi-squared tests were used to test the accuracy of predictions in each class. The model was found to accurately predict occurrences in very low and moderate classes, but underpredicted occurrences in low and high classes. We recommend using similar, data-driven support tools in the conservation decision-making process to minimize losses of the species and maximize efficacy of management. RÉSUMÉ Les modèles de répartition des espèces sont des outils puissants de gestion des espèces rares et en péril, mais leur utilité à ce titre peut être limitée si leur précision est faible ou si les politiques de gestions sont appliquées sans considération de la structure des prédictions. Nous avons évalué la précision d'un modèle de répartition MaxEnt pour la fuscopannaire à taches blanches (Fuscopannaria leucosticta) au Nouveau-Brunswick, Canada, et nous proposons un outil d'aide à la décision qui fait correspondre la probabilité d'occurrence aux procédures de gestion possibles. Le modèle a été testé en utilisant deux ans de nouvelles observations terrain. Des arbres de classification ont été utilisés pour définir quatre groupes parmi la gamme de valeurs de probabilité d'occurrence. Des tests du khi carré ont été utilisés afin d'évaluer la précision des prédictions dans chaque groupe. Le modèle a prédit avec précision les occurrences dans les classes très faibles et modérées, mais a sous-estimé les occurrences dans les classes basses et élevées. Nous recommandons d'utiliser des outils similaires, basés sur des données, dans le processus de prise de décision en matière de conservation pour minimiser les pertes et maximiser l'efficacité de gestion.
{"title":"Translating a Species Distribution Model into Management Recommendations for an at-Risk Lichen","authors":"Alex Setchell, Sean R. Haughian","doi":"10.1080/11956860.2021.1949821","DOIUrl":"https://doi.org/10.1080/11956860.2021.1949821","url":null,"abstract":"ABSTRACT Species distribution models are powerful tools on their own for the management of rare and at-risk species, but their utility as such can be limited if their accuracy is low, or if management policies are applied without consideration of the structure of the data. We tested the accuracy of a MaxEnt species distribution model for white-rimmed shingle lichen (Fuscopannaria leucosticta) in New Brunswick, Canada, and proposed an additional decision support-tool that matches the species probability of occurrence (PO) to possible management actions. The model was tested using two years of new field observations. Classification trees were used to define four groups across the range of PO values. Chi-squared tests were used to test the accuracy of predictions in each class. The model was found to accurately predict occurrences in very low and moderate classes, but underpredicted occurrences in low and high classes. We recommend using similar, data-driven support tools in the conservation decision-making process to minimize losses of the species and maximize efficacy of management. RÉSUMÉ Les modèles de répartition des espèces sont des outils puissants de gestion des espèces rares et en péril, mais leur utilité à ce titre peut être limitée si leur précision est faible ou si les politiques de gestions sont appliquées sans considération de la structure des prédictions. Nous avons évalué la précision d'un modèle de répartition MaxEnt pour la fuscopannaire à taches blanches (Fuscopannaria leucosticta) au Nouveau-Brunswick, Canada, et nous proposons un outil d'aide à la décision qui fait correspondre la probabilité d'occurrence aux procédures de gestion possibles. Le modèle a été testé en utilisant deux ans de nouvelles observations terrain. Des arbres de classification ont été utilisés pour définir quatre groupes parmi la gamme de valeurs de probabilité d'occurrence. Des tests du khi carré ont été utilisés afin d'évaluer la précision des prédictions dans chaque groupe. Le modèle a prédit avec précision les occurrences dans les classes très faibles et modérées, mais a sous-estimé les occurrences dans les classes basses et élevées. Nous recommandons d'utiliser des outils similaires, basés sur des données, dans le processus de prise de décision en matière de conservation pour minimiser les pertes et maximiser l'efficacité de gestion.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"29 1","pages":"159 - 165"},"PeriodicalIF":1.3,"publicationDate":"2021-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45439072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-13DOI: 10.1080/11956860.2021.1958536
G. Ghafoor, F. Sharif, Amin Ul Haq Khan, M. G. Shahid, Z. Siddiq, L. Shahzad
ABSTRACT This study investigated the short-term impacts of projected climate warming on two dominant tree species of the Hayat-ul-Mir subtropical scrub forest of Pakistan. Seedlings of Acacia modesta and Olea ferruginea were exposed to ambient (To) and warming temperature (To + 2.3°C and To + 4.5°C) with control (M15%) and elevated (M20%) soil moisture in plant growth chamber for 90 days. To + 4.5°C induced detrimental effects on both species inhibiting seed germination and reducing their growth rate, biomass accumulation and allocation, however promoted development of root nodules (12 ± 4,0 nodules/root) in A. modesta. To + 2.3°C with M20% was beneficial for O. ferruginea with significant increase in stem height (4.8 ± 1.4 cm), elongated roots (31.2 ± 3.4 cm), branch development (9 ± 1.7), biomass accumulation (8.69 ± 0.4 g) and higher foliar nutrient concentration but for A. modesta it only promoted root elongation (16.5 ± 1.3 cm) and biomass accumulation in stem (1.05 ± 0.1 g) and foliage (0.08 ± 0.001 g). A. modesta grew better under To with significantly high germination and survival rate. A future 2.3°C warming could be ecologically significant to induce shifts in the structure and function of the Hayat-ul-Mir forest. RÉSUMÉ Cette étude a évalué les effets à court terme du réchauffement climatique projeté sur deux espèces arborescentes dominantes de la forêt arbustive subtropicale Hayat-ul-Mir au Pakistan. Des plantules de Acacia modesta et de Olea ferruginea ont été exposées à la température ambiante (To) ou à des réchauffements (To + 2,3°C et To + 4,5°C), selon une humidité du sol témoin (M15%) ou élevée (M20%) dans des chambres de croissance pendant 90 jours. To + 4,5°C a eu des effets délétères sur les deux espèces, empêchant la germination des graines et réduisant la croissance, l'accumulation et l'allocation de biomasse. Toutefois, To + 4,5°C a favorisé le développement de nodules racinaires (12 ± 4,0 nodules/racine) chez A. modesta. To + 2,3°C avec M20% a été bénéfique pour O. ferruginea, entraînant une augmentation significative de la hauteur des tiges (4,8 ± 1,4 cm), l'élongation racinaire (31,2 ± 3,4 cm), le développement de branches (9 ± 1,7), l'accumulation de biomasse (8,69 ± 0,4 g) et une concentration foliaire en nutriments plus élevée. Toutefois, chez A. modesta, To + 2,3°C avec M20% a seulement favorisé l'élongation racinaire (16,5 ± 1,3 cm) et l'accumulation de biomasse dans les tiges (1,05 ± 0,1 g) et dans les feuilles (0,08 ± 0,001 g). A. modesta a cru davantage sous To, affichant une germination et un taux de survie significativement élevés. Un réchauffement futur de 2,3°C pourrait être significatif écologiquement en entraînant des changements de structure et de fonction de la forêt Hayat-ul-Mir.
{"title":"Effect of Climate Warming on Seedling Growth and Biomass Accumulation of Acacia modesta and Olea ferruginea in a Subtropical Scrub Forest of Pakistan","authors":"G. Ghafoor, F. Sharif, Amin Ul Haq Khan, M. G. Shahid, Z. Siddiq, L. Shahzad","doi":"10.1080/11956860.2021.1958536","DOIUrl":"https://doi.org/10.1080/11956860.2021.1958536","url":null,"abstract":"ABSTRACT This study investigated the short-term impacts of projected climate warming on two dominant tree species of the Hayat-ul-Mir subtropical scrub forest of Pakistan. Seedlings of Acacia modesta and Olea ferruginea were exposed to ambient (To) and warming temperature (To + 2.3°C and To + 4.5°C) with control (M15%) and elevated (M20%) soil moisture in plant growth chamber for 90 days. To + 4.5°C induced detrimental effects on both species inhibiting seed germination and reducing their growth rate, biomass accumulation and allocation, however promoted development of root nodules (12 ± 4,0 nodules/root) in A. modesta. To + 2.3°C with M20% was beneficial for O. ferruginea with significant increase in stem height (4.8 ± 1.4 cm), elongated roots (31.2 ± 3.4 cm), branch development (9 ± 1.7), biomass accumulation (8.69 ± 0.4 g) and higher foliar nutrient concentration but for A. modesta it only promoted root elongation (16.5 ± 1.3 cm) and biomass accumulation in stem (1.05 ± 0.1 g) and foliage (0.08 ± 0.001 g). A. modesta grew better under To with significantly high germination and survival rate. A future 2.3°C warming could be ecologically significant to induce shifts in the structure and function of the Hayat-ul-Mir forest. RÉSUMÉ Cette étude a évalué les effets à court terme du réchauffement climatique projeté sur deux espèces arborescentes dominantes de la forêt arbustive subtropicale Hayat-ul-Mir au Pakistan. Des plantules de Acacia modesta et de Olea ferruginea ont été exposées à la température ambiante (To) ou à des réchauffements (To + 2,3°C et To + 4,5°C), selon une humidité du sol témoin (M15%) ou élevée (M20%) dans des chambres de croissance pendant 90 jours. To + 4,5°C a eu des effets délétères sur les deux espèces, empêchant la germination des graines et réduisant la croissance, l'accumulation et l'allocation de biomasse. Toutefois, To + 4,5°C a favorisé le développement de nodules racinaires (12 ± 4,0 nodules/racine) chez A. modesta. To + 2,3°C avec M20% a été bénéfique pour O. ferruginea, entraînant une augmentation significative de la hauteur des tiges (4,8 ± 1,4 cm), l'élongation racinaire (31,2 ± 3,4 cm), le développement de branches (9 ± 1,7), l'accumulation de biomasse (8,69 ± 0,4 g) et une concentration foliaire en nutriments plus élevée. Toutefois, chez A. modesta, To + 2,3°C avec M20% a seulement favorisé l'élongation racinaire (16,5 ± 1,3 cm) et l'accumulation de biomasse dans les tiges (1,05 ± 0,1 g) et dans les feuilles (0,08 ± 0,001 g). A. modesta a cru davantage sous To, affichant une germination et un taux de survie significativement élevés. Un réchauffement futur de 2,3°C pourrait être significatif écologiquement en entraînant des changements de structure et de fonction de la forêt Hayat-ul-Mir.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"29 1","pages":"133 - 146"},"PeriodicalIF":1.3,"publicationDate":"2021-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44006707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-11DOI: 10.1080/11956860.2021.1943931
Brenda Shaughnessy, A. Dhar, M. Naeth
ABSTRACT Stockpiling of soils is essential for reclamation after oil sands mining, and can influence revegetation through degradation of seed viability and soil quality. Three peat-mineral stockpiled areas in upland boreal forest, aged 26 to 34 years, were assessed for effects on soil, vegetation, and successional status to study the natural recovery of vegetation. Six upland (five native, one nonnative) and one lowland native species community types were identified where non-vascular had more communities than vascular plants. Upland boreal species that were likely not present in the soil seed bank, colonized the sites relatively quickly with a plant community of early to mid successionals, including persistence of a lowland species (Amblystegium serpens) and nonnatives. Presence of a non-native community (Melilotus officinalis) 26 to 34 years after reclamation can be concerning. Stockpiled soil texture (clay) and tall shrub stem density were most influential on plant community development. Stem density (DBH > 5 cm), self-thinning of early successional species (Salix, Betula papyrifera), and presence of climax species (Picea glauca) resembled the successional trend of natural boreal forests in the region. Results from this study suggest natural recovery of upland boreal forest on lowland peat substrate is possible and can support evolving plant communities.
{"title":"Natural Recovery of Vegetation on Reclamation Stockpiles After 26 to 34 Years","authors":"Brenda Shaughnessy, A. Dhar, M. Naeth","doi":"10.1080/11956860.2021.1943931","DOIUrl":"https://doi.org/10.1080/11956860.2021.1943931","url":null,"abstract":"ABSTRACT Stockpiling of soils is essential for reclamation after oil sands mining, and can influence revegetation through degradation of seed viability and soil quality. Three peat-mineral stockpiled areas in upland boreal forest, aged 26 to 34 years, were assessed for effects on soil, vegetation, and successional status to study the natural recovery of vegetation. Six upland (five native, one nonnative) and one lowland native species community types were identified where non-vascular had more communities than vascular plants. Upland boreal species that were likely not present in the soil seed bank, colonized the sites relatively quickly with a plant community of early to mid successionals, including persistence of a lowland species (Amblystegium serpens) and nonnatives. Presence of a non-native community (Melilotus officinalis) 26 to 34 years after reclamation can be concerning. Stockpiled soil texture (clay) and tall shrub stem density were most influential on plant community development. Stem density (DBH > 5 cm), self-thinning of early successional species (Salix, Betula papyrifera), and presence of climax species (Picea glauca) resembled the successional trend of natural boreal forests in the region. Results from this study suggest natural recovery of upland boreal forest on lowland peat substrate is possible and can support evolving plant communities.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"29 1","pages":"55 - 67"},"PeriodicalIF":1.3,"publicationDate":"2021-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49488941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-02DOI: 10.1080/11956860.2021.1952014
A. Delwaide, Hugo Asselin, D. Arseneault, C. Lavoie, S. Payette
ABSTRACT We present the longest tree-ring chronology to date in northeastern North America (2233 years; 227 BCE – 2005 CE), resulting from several research projects conducted at the subarctic treeline in northern Quebec. This raw chronology of tree-ring width includes 464 black spruce (Picea mariana (Mill.) B.S.P.) shrubs (krummholz) growing in wetlands and preserved within peatlands. An indexed series of 152 erect black spruce trees that have lived in wetlands is also presented, covering the period 216 BCE to 1619 CE. We compared these chronologies to a tree-ring series including 116 black spruce trees and krummholz having grown on well-drained lichen woodlands over the period 1304–2000 CE. These chronologies highlight the major climatic periods of the last two millennia. Floating chronologies dating from 2500 to 3500 years ago were also developed from trees preserved in frozen peat. Growth rings from this period are much wider than those of the last 2233 years, suggesting warm climatic conditions and permafrost-free peatlands during the transition from mid- to late Holocene. The three subarctic chronologies presented here underscore the relevance and usefulness of tree growth rings and growth forms as ecological tools to assess the influence of climate on subarctic ecosystems.
{"title":"A 2233-Year Tree-Ring Chronology of Subarctic Black Spruce (Picea mariana): Growth Forms Response to Long-Term Climate Change","authors":"A. Delwaide, Hugo Asselin, D. Arseneault, C. Lavoie, S. Payette","doi":"10.1080/11956860.2021.1952014","DOIUrl":"https://doi.org/10.1080/11956860.2021.1952014","url":null,"abstract":"ABSTRACT We present the longest tree-ring chronology to date in northeastern North America (2233 years; 227 BCE – 2005 CE), resulting from several research projects conducted at the subarctic treeline in northern Quebec. This raw chronology of tree-ring width includes 464 black spruce (Picea mariana (Mill.) B.S.P.) shrubs (krummholz) growing in wetlands and preserved within peatlands. An indexed series of 152 erect black spruce trees that have lived in wetlands is also presented, covering the period 216 BCE to 1619 CE. We compared these chronologies to a tree-ring series including 116 black spruce trees and krummholz having grown on well-drained lichen woodlands over the period 1304–2000 CE. These chronologies highlight the major climatic periods of the last two millennia. Floating chronologies dating from 2500 to 3500 years ago were also developed from trees preserved in frozen peat. Growth rings from this period are much wider than those of the last 2233 years, suggesting warm climatic conditions and permafrost-free peatlands during the transition from mid- to late Holocene. The three subarctic chronologies presented here underscore the relevance and usefulness of tree growth rings and growth forms as ecological tools to assess the influence of climate on subarctic ecosystems.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"28 1","pages":"399 - 419"},"PeriodicalIF":1.3,"publicationDate":"2021-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/11956860.2021.1952014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44119005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-02DOI: 10.1080/11956860.2021.1949820
Mariane Patrezi Zanatta, João Pedro Costa Elias, Caroline Cambraia Furtado Campos, S. Mortara, F. Ramos
ABSTRACT Bamboos, abundant in tropical forests, have high potential to dominate disturbed areas due to their high vegetative growth rate and preference for disturbed habitats. However, there are no studies exploring the influence of forest patch characteristics and anthropogenic land-use on bamboo populations. We investigated the influence of landscape matrix characteristics on the abundance of two bamboo taxa (Merostachys sp. and Parodiolyra micrantha) across two different spatial scales: 600 m (113 ha) and 1000 m (314 ha). We sampled the edge of 15 forest fragments (from 20.3 to 116.5 ha) in a highly disturbed landscape in Alfenas, Brasil. Only P. micrantha abundance was influenced by landscape metrics: positively by the percentage of sugarcane and coffee plantations around a forest fragment at 600 m, and negatively by the percentage of pasture at 1000 m. We suggest that cattle presence and/or the edge effect intensified by the adjacent pasture matrices could explain the negative effect of pasture, and that the disturbance caused by sugarcane and coffee plantations might explain the positive influence on P. micrantha abundance, a generalist and competitive understory species. Our results could help decision makers in their attempts to control bamboo populations and manage the landscape around forest fragments. RÉSUMÉ Abondants dans les forêts tropicales, les bambous ont un potentiel élevé de dominer les zones perturbées en raison de leur préférence pour ce type d'habitat et de leur croissance végétative élevée. Toutefois, aucune étude n'a encore exploré l'influence des caractéristiques de parcelles forestières et de l'utilisation humaine du territoire sur les populations de bambou. Nous avons étudié l'influence des caractéristiques de la matrice paysagère sur l'abondance de deux taxons de bambou (Merostachys sp. et Parodiolyra micrantha) à deux échelles spatiales différentes: 600 m (113 ha) et 1000 m (314 ha). Nous avons échantillonné la bordure de 15 fragments forestiers (de 20,3 à 116,5 ha) dans un paysage hautement perturbé à Alfenas (Brésil). Seule l'abondance de P. micrantha était influencée par les caractéristiques paysagères: positivement par le pourcentage de plantations de canne à sucre et de café à 600 m autour du fragment forestier, et négativement par le pourcentage de pâturages à 1000 m. Nous suggérons que la présence de bétail et/ou l'intensification de l'effet de bordure par les matrices de pâturage adjacentes pourrait expliquer l'effet négatif du pâturage, et que les perturbations causées par les plantations de canne à sucre et de café pourraient expliquer l'effet positif sur l'abondance de P. micrantha, une espèce de sous-couvert généraliste et compétitive. Nos résultats pourront aider la prise de décision en matière de contrôle des populations de bambou et d'aménagement des paysages autour des fragments forestiers.
{"title":"Differential Effect of Agricultural Matrices on Bamboo Abundance in Forest Fragments","authors":"Mariane Patrezi Zanatta, João Pedro Costa Elias, Caroline Cambraia Furtado Campos, S. Mortara, F. Ramos","doi":"10.1080/11956860.2021.1949820","DOIUrl":"https://doi.org/10.1080/11956860.2021.1949820","url":null,"abstract":"ABSTRACT Bamboos, abundant in tropical forests, have high potential to dominate disturbed areas due to their high vegetative growth rate and preference for disturbed habitats. However, there are no studies exploring the influence of forest patch characteristics and anthropogenic land-use on bamboo populations. We investigated the influence of landscape matrix characteristics on the abundance of two bamboo taxa (Merostachys sp. and Parodiolyra micrantha) across two different spatial scales: 600 m (113 ha) and 1000 m (314 ha). We sampled the edge of 15 forest fragments (from 20.3 to 116.5 ha) in a highly disturbed landscape in Alfenas, Brasil. Only P. micrantha abundance was influenced by landscape metrics: positively by the percentage of sugarcane and coffee plantations around a forest fragment at 600 m, and negatively by the percentage of pasture at 1000 m. We suggest that cattle presence and/or the edge effect intensified by the adjacent pasture matrices could explain the negative effect of pasture, and that the disturbance caused by sugarcane and coffee plantations might explain the positive influence on P. micrantha abundance, a generalist and competitive understory species. Our results could help decision makers in their attempts to control bamboo populations and manage the landscape around forest fragments. RÉSUMÉ Abondants dans les forêts tropicales, les bambous ont un potentiel élevé de dominer les zones perturbées en raison de leur préférence pour ce type d'habitat et de leur croissance végétative élevée. Toutefois, aucune étude n'a encore exploré l'influence des caractéristiques de parcelles forestières et de l'utilisation humaine du territoire sur les populations de bambou. Nous avons étudié l'influence des caractéristiques de la matrice paysagère sur l'abondance de deux taxons de bambou (Merostachys sp. et Parodiolyra micrantha) à deux échelles spatiales différentes: 600 m (113 ha) et 1000 m (314 ha). Nous avons échantillonné la bordure de 15 fragments forestiers (de 20,3 à 116,5 ha) dans un paysage hautement perturbé à Alfenas (Brésil). Seule l'abondance de P. micrantha était influencée par les caractéristiques paysagères: positivement par le pourcentage de plantations de canne à sucre et de café à 600 m autour du fragment forestier, et négativement par le pourcentage de pâturages à 1000 m. Nous suggérons que la présence de bétail et/ou l'intensification de l'effet de bordure par les matrices de pâturage adjacentes pourrait expliquer l'effet négatif du pâturage, et que les perturbations causées par les plantations de canne à sucre et de café pourraient expliquer l'effet positif sur l'abondance de P. micrantha, une espèce de sous-couvert généraliste et compétitive. Nos résultats pourront aider la prise de décision en matière de contrôle des populations de bambou et d'aménagement des paysages autour des fragments forestiers.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"29 1","pages":"89 - 102"},"PeriodicalIF":1.3,"publicationDate":"2021-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/11956860.2021.1949820","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44055425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-27DOI: 10.1080/11956860.2021.1949819
J. Perreault, R. Fortier, J. Molson
ABSTRACT Numerical simulations were carried out based on a conceptual cryohydrogeological model of a permafrost mound near Umiujaq, Nunavik (Québec), Canada, to assess the impacts of climate warming and changes in surface conditions on permafrost degradation. The 2D model includes groundwater flow, advective-conductive heat transport, phase change and latent heat. Changes in surface conditions which are characteristic of the site were represented empirically in the model by applying spatially- and temporally-variable ground surface temperatures derived from linear regressions between monitored surface and air temperatures. After reaching a transient steady-state condition close to present-day conditions, the simulations were then extended to 2100 under hypothetical climate warming scenarios and using imposed changes in surface conditions consistent with observed on-site evolution. The simulations show that the development of a thermokarst pond and shrubification respectively induce ground warming of up to 0.5°C and 1.5°C, upward migration of the permafrost base by up to 2 and 4 m, and a decrease in the lateral permafrost extent of 1 and 7 m, relative to a reference case without changes in surface conditions. Feedback from permafrost degradation which drives changes in ground surface conditions should be included in future numerical modelling of permafrost dynamics.
{"title":"Numerical Modelling of Permafrost Dynamics under Climate Change and Evolving Ground Surface Conditions: Application to an Instrumented Permafrost Mound at Umiujaq, Nunavik (Québec), Canada","authors":"J. Perreault, R. Fortier, J. Molson","doi":"10.1080/11956860.2021.1949819","DOIUrl":"https://doi.org/10.1080/11956860.2021.1949819","url":null,"abstract":"ABSTRACT Numerical simulations were carried out based on a conceptual cryohydrogeological model of a permafrost mound near Umiujaq, Nunavik (Québec), Canada, to assess the impacts of climate warming and changes in surface conditions on permafrost degradation. The 2D model includes groundwater flow, advective-conductive heat transport, phase change and latent heat. Changes in surface conditions which are characteristic of the site were represented empirically in the model by applying spatially- and temporally-variable ground surface temperatures derived from linear regressions between monitored surface and air temperatures. After reaching a transient steady-state condition close to present-day conditions, the simulations were then extended to 2100 under hypothetical climate warming scenarios and using imposed changes in surface conditions consistent with observed on-site evolution. The simulations show that the development of a thermokarst pond and shrubification respectively induce ground warming of up to 0.5°C and 1.5°C, upward migration of the permafrost base by up to 2 and 4 m, and a decrease in the lateral permafrost extent of 1 and 7 m, relative to a reference case without changes in surface conditions. Feedback from permafrost degradation which drives changes in ground surface conditions should be included in future numerical modelling of permafrost dynamics.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"28 1","pages":"377 - 397"},"PeriodicalIF":1.3,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/11956860.2021.1949819","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48880565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-07DOI: 10.1080/11956860.2021.1943930
S. Lalonde, J. L. McCune, S. Rivest, Heather M. Kharouba
ABSTRACT Over the past two decades, monarch butterfly populations have been declining. This decline has been partly attributed to the extensive loss of breeding habitat through the reduction of common milkweed (Asclepias syriaca, the larval host plant) through herbicides. While the decline of milkweed has been well documented in the US, less is known about its decline in Canada. To take a first step in quantifying its potential decline, we compared roadside milkweed abundance at sites around Ottawa, Ontario, Canada in 2018, to a county-wide estimate of milkweed abundance in 1943 and 1944. We also evaluated the effect of roadside characteristics on milkweed abundance at these sites. Current milkweed density in the Ottawa region is 33–86% lower than it was 75 years ago. We found milkweed at 67% of our 100 sites and found less milkweed at sites with a higher number of lanes in the road adjacent to the roadside. Interestingly, mowing indices were not significant predictors of milkweed abundance. Here we document the first quantitative evidence for milkweed decline over the past 75 years in Canada, which has likely contributed to the decline of breeding monarchs in Canada.
{"title":"Decline in Common Milkweed along Roadsides Around Ottawa, Canada","authors":"S. Lalonde, J. L. McCune, S. Rivest, Heather M. Kharouba","doi":"10.1080/11956860.2021.1943930","DOIUrl":"https://doi.org/10.1080/11956860.2021.1943930","url":null,"abstract":"ABSTRACT Over the past two decades, monarch butterfly populations have been declining. This decline has been partly attributed to the extensive loss of breeding habitat through the reduction of common milkweed (Asclepias syriaca, the larval host plant) through herbicides. While the decline of milkweed has been well documented in the US, less is known about its decline in Canada. To take a first step in quantifying its potential decline, we compared roadside milkweed abundance at sites around Ottawa, Ontario, Canada in 2018, to a county-wide estimate of milkweed abundance in 1943 and 1944. We also evaluated the effect of roadside characteristics on milkweed abundance at these sites. Current milkweed density in the Ottawa region is 33–86% lower than it was 75 years ago. We found milkweed at 67% of our 100 sites and found less milkweed at sites with a higher number of lanes in the road adjacent to the roadside. Interestingly, mowing indices were not significant predictors of milkweed abundance. Here we document the first quantitative evidence for milkweed decline over the past 75 years in Canada, which has likely contributed to the decline of breeding monarchs in Canada.","PeriodicalId":51030,"journal":{"name":"Ecoscience","volume":"29 1","pages":"25 - 37"},"PeriodicalIF":1.3,"publicationDate":"2021-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/11956860.2021.1943930","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44575547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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