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3. Alternative silvicultural practices in irregular boreal forests: response of beetle assemblages

Author

Légaré, Jean-Philippe, Hébert, Christian, and Ruel, Jean-Claude

Subjects
Forestry, SD1-669.5
Abstract

In the process of implementing sustainable management in the eastern Canadian boreal forest, we tested two selection cutting methods and compared them with two widely used practices in the boreal forest: clearcutting with protection of the advanced growth and soils and irregular shelterwood cutting leaving small merchantable stems. We used old-growth irregular stands as references in comparing the impact of these silvicultural treatments on the diversity and abundance of beetles. Three groups were targeted: saproxylic flying beetles, epigaeic saproxylic beetles and epigaeic non-saproxylic beetles. A sampling design including 320 pitfall traps and 80 multidirectional flight-interception traps was deployed in 2007. A total of 26 906 beetles was captured including 407 taxa distributed among 52 families. We found that clearcutting with protection of the advanced growth and soils and irregular shelterwood cutting leaving small merchantable stems had a greater impact on beetle communities than both selection cuttings. Canopy opening as well as the presence of snags and downed woody debris appear as important attributes for several saproxylic and non-saproxylic species. Beetle communities in selection cuttings remained more similar to those found in controls; these silvicultural treatments are new tools to implement ecosystemic and sustainable management in irregular boreal forests.

Published
2011
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4. Forest Arthropod Diversity

Author

Hébert, Christian, D. Allison, Jeremy, editor, Paine, Timothy D., editor, Slippers, Bernard, editor, and Wingfield, Michael J., editor

Published
2023
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7. The contribution of insects to global forest deadwood decomposition

Author

Seibold, Sebastian, Rammer, Werner, Hothorn, Torsten, Seidl, Rupert, Ulyshen, Michael D., Lorz, Janina, Cadotte, Marc W., Lindenmayer, David B., Adhikari, Yagya P., Aragón, Roxana, Bae, Soyeon, Baldrian, Petr, Barimani Varandi, Hassan, Barlow, Jos, Bässler, Claus, Beauchêne, Jacques, Berenguer, Erika, Bergamin, Rodrigo S., Birkemoe, Tone, Boros, Gergely, Brandl, Roland, Brustel, Hervé, Burton, Philip J., Cakpo-Tossou, Yvonne T., Castro, Jorge, Cateau, Eugénie, Cobb, Tyler P., Farwig, Nina, Fernández, Romina D., Firn, Jennifer, Gan, Kee Seng, González, Grizelle, Gossner, Martin M., Habel, Jan C., Hébert, Christian, Heibl, Christoph, Heikkala, Osmo, Hemp, Andreas, Hemp, Claudia, Hjältén, Joakim, Hotes, Stefan, Kouki, Jari, Lachat, Thibault, Liu, Jie, Liu, Yu, Luo, Ya-Huang, Macandog, Damasa M., Martina, Pablo E., Mukul, Sharif A., Nachin, Baatarbileg, Nisbet, Kurtis, O’Halloran, John, Oxbrough, Anne, Pandey, Jeev Nath, Pavlíček, Tomáš, Pawson, Stephen M., Rakotondranary, Jacques S., Ramanamanjato, Jean-Baptiste, Rossi, Liana, Schmidl, Jürgen, Schulze, Mark, Seaton, Stephen, Stone, Marisa J., Stork, Nigel E., Suran, Byambagerel, Sverdrup-Thygeson, Anne, Thorn, Simon, Thyagarajan, Ganesh, Wardlaw, Timothy J., Weisser, Wolfgang W., Yoon, Sungsoo, Zhang, Naili, and Müller, Jörg

Published
2021
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9. Impacts of salvage logging on biodiversity: A meta-analysis

Author

Thorn, Simon, Bässler, Claus, Brandl, Roland, Burton, Philip J., Cahall, Rebecca, Campbell, John L., Castro, Jorge, Choi, Chang-Yong, Cobb, Tyler, Donato, Daniel C., Durska, Ewa, Fontaine, Joseph B., Gauthier, Sylvie, Hebert, Christian, Hothorn, Torsten, Hutto, Richard L., Lee, Eun-Jae, Leverkus, Alexandro B., Lindenmayer, David B., Obrist, Martin K., Rost, Josep, Seibold, Sebastian, Seidl, Rupert, Thom, Dominik, Waldron, Kaysandra, Wermelinger, Beat, Winter, Maria-Barbara, Zmihorski, Michal, and Müller, Jörg

Published
2018

14. Premium food for offspring? Black-backed Woodpecker (Picoides arcticus) diet during breeding season in eastern Canada

Author

Tremblay, Junior A., Fontaine, Gabriel L., Savard, Jean-Pierre L., Béland, Jean-Michel, Hébert, Christian, Ibarzabal, Jacques, Tremblay, Junior A., Fontaine, Gabriel L., Savard, Jean-Pierre L., Béland, Jean-Michel, Hébert, Christian, and Ibarzabal, Jacques

Abstract

Knowledge on the diet of the Black-backed Woodpecker (Picoides arcticus Swainson, 1832) is fragmentary and relies on a limited number of studies. Gaps remain in our understanding of the plasticity of its diet, particularly in the eastern part of its range. The main objective of this study was to assess the diet of Black-backed Woodpeckers in burned and unburned habitats and among sexes and ages in Québec. We collected feces and fecal bags from unburned and burned habitats in the Central Laurentians ecoregion of the eastern boreal shield ecozone and assessed diets based on identified prey items. Buprestidae and Cerambycidae of the sub-family Lamiinae were the predominant prey for adult Black-backed Woodpeckers in burned habitats, and the Pythidae Pytho niger (Kirby, 1837) and Lamiinae were the most prevalent prey in unburned habitats. Lamiinae were the most predominant prey items provisioned to nestling in burned habitat, while P. niger was their predominant food in unburned habitat, followed by Cerambycidae (without Lamiinae) and Lamiinae. Our results present new insights into Black-backed Woodpecker diet where parents feed their offspring with the largest prey available, potentially providing higher fitness for their offspring. Furthermore, our study confirms that Black-backed Woodpeckers, at least in the eastern part of its range, are not restricted to feed on Lamiinae but are rather opportunistic in taking advantage from resource–pulse interactions provided by recently disturbed habitats, especially from recently burned habitats.

Published
2023
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17. Optimizing Bacillus thuringiensis (Btk) Aerial Spray Prescriptions in Mixed Balsam Fir-White Spruce Stands against the Eastern Spruce Budworm.

Author

Fuentealba, Alvaro, Pelletier-Beaulieu, Émile, Dupont, Alain, Hébert, Christian, Berthiaume, Richard, and Bauce, Éric

Subjects
SPRUCE budworm, BACILLUS thuringiensis, WHITE spruce, BALSAM fir, FOREST protection
Abstract

Forest protection against eastern spruce budworm, Choristoneura fumiferana (Clemens), relies on aerial applications of Bacillus thuringiensis (Btk). However, Btk prescriptions have been developed for balsam fir (Abies balsamea (L.) Mill.) stands, generating uncertainty as to the relevance of this protection approach on white spruce (Picea glauca (Moench) Voss). The main goal of this study was to evaluate the efficacy of three Btk application treatments (early application, late application, and double application) for protecting white spruce and balsam fir in mixed stands. Our results show that all Btk treatments tested kept defoliation under the 50% threshold on balsam fir (27.7 to 38.1% less defoliation than in controls). In contrast, differences in defoliation among treatments were not significant for white spruce. Larval mortality was significantly lower on white spruce than on balsam fir. The low efficacy of Btk treatments on white spruce may be explained by its shoot phenology (most bud caps were still present during the early application), and its foliar chemistry, which could decrease Btk efficacy. Consequently, many larvae may survive simply because Btk spores do not reach them, or because they may consume sublethal doses. We recommend maintaining the current strategy in mixed stands, as it provides a good protection for balsam fir. Further research is needed to determine the causes of the low efficacy of Btk treatments on white spruce. [ABSTRACT FROM AUTHOR]

Published
2023
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34. Testing the effect of snag and cavity supply on deadwood-associated species in a managed boreal forest

Author

Dufour-Pelletier, Samuel, Tremblay, Junior A., Hébert, Christian, Lachat, Thibault, Ibarzabal, Jacques, Dufour-Pelletier, Samuel, Tremblay, Junior A., Hébert, Christian, Lachat, Thibault, and Ibarzabal, Jacques

Abstract

Standing deadwood is an important attribute of old-growth boreal forests and it provides essential microhabitats for deadwood-associated species. In managed boreal forests, short rotations tend to limit the amount and diversity of standing deadwood. This study evaluates if the anthropogenic supply of deadwood attributes through tree girdling or by providing nest boxes may favor deadwood-associated species. We studied the short-term response of saproxylic beetles, foraging woodpeckers, and secondary cavity users to snag and cavity supply in 50 to 70-year-old black spruce stands. In spring 2015, we girdled 8000 black spruce according to two spatial distributions (uniform and clustered), and we also installed 450 nest boxes of six different sizes at three distances from the forest edge. Using trunk window traps, we captured significantly more beetles in sites with girdled trees than in control sites in both 2015 and 2016. We also recorded a trend of a greater abundance of beetles in clusters of girdled trees than within uniformly distributed girdled trees. Trypodendron lineatum (Oliver) dominated beetle assemblages, representing 88.5% of all species in 2015 and 74.6% in 2016. The number of beetles captured was 7× higher in 2015 than in 2016. In contrast, we observed greater amounts of woodpecker foraging marks in fall 2016 than in either fall 2015 or spring 2016. Woodpeckers foraged significantly more in clusters of girdled trees than within uniformly distributed girdled trees. Woodpeckers’ foraging mark presence was positively associated with the proportion of recent cuts at 1 km around the study sites. Five Boreal Chickadee (Poecile hudsonicus Forster) pairs used nest boxes and occupied smaller box sizes that were located away from the forest edge. Our study showed that structural enrichment can be effective in rapidly attracting deadwood-associated species within managed forest stands.

Published
2020

46. Films minces nanocomposites ZnxFe1-xO1+δ : phases wurtzite, sel gemme et spinelle

Author

Hébert, Christian, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris VI, and Nathalie Jedrecy

Subjects
Spinel Zn : Fe3O4, Phase Fe : ZnO, Films nanocomposites, Ferromagnétisme/antiferromagnétisme, Ferrromagnetic/antiferromagnetic, Spinelle Zn : Fe3O4, Couplage d'échange, Nanocomposites films, Magnéto-transport, [CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

This thesis deals with the growth of thin films of zinc/iron oxides (ZnxFe1-xO1+δ) by pulsed laser deposition (PLD) and the possibility of controlling their structural and physicochemical properties by varying the elaboration conditions: oxygen pressure and growth temperature, respective proportions of zinc/iron. For high values of x (x> 65%), the films are single-phase with a ZnO-type wurtzite structure (Fe:ZnO films), with 80% optical transparency in the UV-visible range but without ferromagnetic properties; depending on their iron (1-x) content, they evolve from very good electrical conductors to near-insulators. For small values of x (x 65%), les films sont monophasés de structure wurtzite type ZnO (films Fe:ZnO), avec une transparence optique dans la gamme UV-visible de 80% mais sans propriété ferromagnétique ; en fonction de leur teneur en fer (1-x), ils évoluent de très bons conducteurs électriques à quasi-isolants. Pour de faibles valeurs de x (x < 15%), les films sont également monophasés de structure spinelle type Fe3O4 (films Zn:Fe3O4). Ils présentent de très bonnes propriétés ferromagnétiques dès la température ambiante ainsi qu’une bonne conductivité électrique, les effets de localisation des porteurs de charge se manifestant en dessous de la température de Verwey. Le nombre de parois d’antiphase peut être diminué par une croissance en deux étapes, comme l’atteste les mesures de magnétorésistance. Aux taux intermédiaires de zinc (15% < x < 65%), les films sont nano-composites. Dans le cas d’une coexistence des phases Fe:ZnO et Zn:Fe3O4, la bonne conductivité de Zn:Fe3O4 jointe à la multiplicité des variantes épitaxiales et donc des interfaces fournit un matériau adapté à la thermoélectricité. Dans le cas d’une coexistence de la phase ferrromagnétique Zn:Fe3O4 avec la phase Zn:FeO antiferromagnétique de type sel gemme, un fort couplage d’échange ainsi qu’une anisotropie magnétique perpendiculaire élevée sont mis en évidence.

Published
2017

47. Exploitation fine des mines urbaines par la mutualisation: réduction des Gaz à Effet de Serre mondiaux par l'action locale : contrats économique, social et environnemental

Author

Hébert, Christian, Collaboration, and Balsiger, Jörg

Subjects
Agenda 2030, MPS, Tri, Écologie politique, Cycle de vie, Déchets, Éthique environnementale, TVA circulaire, Poubelle Genevoise, Capital sympathie, Obsolescences, Économie sociale et solidaire, Gains énergétiques, ESS, Richesse mondiale, Boucle du cycle durable, Matière première secondaire, ddc:333.7-333.9, Nudge, Richesses locales, GES, Mines urbaines, Écologie solidaire, Recycleur récompensé, Yes fils, Chimie verte, Plan climat cantonal, Oui can, Recyclage, Coopérative, Écologie sociale
Abstract

Demain Genève Place financière environnementale ? Centre logistique des multinationales minière responsables ? Premier centre d'échange des Matières Premières Secondaires (MPS) ? 3 Contrats pour Agenda 2030 Contrat 1 : Social Les engagements et volontés des pouvoirs politiques, d'obtenir des résultats tangibles dans la réduction des Gaz à Effet de Serre (GES), facteur du changement climatique à l'Agenda 2030. Applique le concept des « Mines Urbaines » dans la double boucle du cycle de vie en développement durable. Développe le CAPITAL SYMPATHIE, en notion dynamique, à la participation des citoyens comme des récupérateurs récompensés. Contrat 2 : Economique Pour se faire, Genève mutualise les acteurs industriels, financiers et associatifs, pour la plus grande transversalité dans un projet ambitieux. Recycler les métaux précieux autant que rares, présents localement dans nos biens de consommation obsolescents. Les compétences cumulées des acteurs, permettent une valorisation fine des composants, un recyclage performant préservant les matières, pour les générations futures. Contrat 3 : Environnementale Avec des procédés issus de la chimie verte, comme la capacité de l'eau supercritique, de dissocier les polymères des métaux et terres rares de façon écologique, un nouveau modèle d'extraction responsable voit jour dans le Canton de Genève. Réduisant ainsi, la pression sur l'extraction de matière vierge et par rebond une réduction significative des GES mondiaux, par l'action locale.

Published
2017

48. The Cryptophagidae of Canada and the northern United States of America.

Author

Pelletier, Georges and Hébert, Christian

Subjects
*DATA distribution, *DATA mapping, *GEOGRAPHIC boundaries
Abstract

This review of Cryptophagidae of Canada and the Northern United States (US) covers 142 species among the following genera: Caenoscelis (6 species), Antherophagus (4), Cryptophagus (33), Henoticus (4), Henotiderus (2), Micrambe (1), Myrmedophila (1), Pteryngium (1), Salebius (2), Telmatophilus (2), Hypocoprus (1), Atomaria (81), Curelius (1), Ephistemus (2) and Tisactia (1). All species are described morphologically and descriptions include high-definition photographs, geographic distribution data and maps as well as data on seasonal occurrence, habitats and the number of specimens examined. Some already described species that have not yet been recorded in Canada, but that have been found in bordering states with similar habitats, are also included in this publication. An interactive identification key is provided to identify all known species in Canada and Alaska together with a descriptive page for each species. [ABSTRACT FROM AUTHOR]

Published
2019
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