Treesearch
Displaying 3,901 - 3,910 of 64,719 Publications- For many forest landscape ecology and ecological monitoring projects, forest structure and composition data availability at the correct scale are often limiting factors, motivating the development of map products based on remote sensing. Gradient nearest neighbor (GNN) imputation is a flexible framework for generating multivariate, annual, wall-to-wall maps of forest structure and composition for landscape, regional, and national applications. This report provides guidance on the appropriate use of forest structure and composition maps generated from satellite imagery, physical environment,...AuthorsDavid M. Bell, Matthew J. Gregory, Marin Palmer, Raymond DavisKeywordsSourceGen. Tech. Rep. PNW-GTR-1018. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 41 p. (Online only).Year2023
- The benefits of masting (volatile, quasi-synchronous seed production at lagged intervals) include satiation of seed predators, but these benefits come with a cost to mutualist pollen and seed dispersers. If the evolution of masting represents a balance between these benefits and costs, we expect mast avoidance in species that are heavily reliant on mutualist dispersers. These effects play out in the context of variable climate and site fertility among species that vary widely in nutrient demand. Meta-analyses of published data have focused on variation at the population scale, thus...AuthorsAmy V Whipple, Thomas G. Whitham, Andreas P. Wion, S. Joseph Wright, Kai Zhu, Jess K. Zimmerman, Magdalena Zywiec, James S. Clark, Tong Qiu, Marie-Claire Aravena, Davide Ascoli, Yves Bergeron, Michal Bogdziewicz, Thomas Boivin, Raul Bonal, Thomas Caignard, Maxime Cailleret, Rafael Calama, Sergio Donoso Calderon, J. Julio Camarero, Chia-Hao Chang-Yang, Jerome Chave, Francesco Chianucci, Benoit Courbaud, Andrea Cutini, Adrian J. Das, Nicolas Delpierre, Sylvain Delzon, Michael Dietze, Laurent Dormont, Josep Maria Espelta, Timothy J. Fahey, William Farfan-Rios, Jerry F. Franklin, Catherine A. Gehring, Gregory S. Gilbert, Georg Gratzer, Cathryn H. Greenberg, Arthur Guignabert, Qinfeng Guo, Andrew Hacket-Pain, Arndt Hampe, Qingmin Han, Jan Holik, Kazuhiko Hoshizaki, Ines Ibanez, Jill F. Johnstone, Valentin Journé, Thomas Kitzberger, Johannes M. H. Knops, Georges Kunstler, Hiroko Kurokawa, Jonathan G. A. Lageard, Jalene M. LaMontagne, Francois Lefevre, Theodor Leininger, Jean-Marc Limousin, James A. Lutz, Diana Macias, Anders Marell, Eliot J. B. McIntire, Christopher M. Moore, Emily Moran, Renzo Motta, Jonathan A. Myers, Thomas A. Nagel, Shoji Naoe, Mahoko Noguchi, Michio Oguro, Robert Parmenter, Ian S. Pearse, Ignacio M. Perez-Ramos, Lukasz Piechnik, Tomasz Podgorski, John Poulsen, Miranda D. Redmond, Chantal D. Reid, Kyle C. Rodman, Francisco Rodriguez-Sanchez, Pavel Samonil, Javier D. Sanguinetti, C. Lane Scher, Barbara Seget, Shubhi Sharma, Mitsue Shibata, Miles Silman, Michael A. Steele, Nathan L. Stephenson, Jacob N. Straub, Samantha Sutton, Jennifer J. Swenson, Margaret Swift, Peter A. Thomas, Maria Uriarte, Giorgio VacchianoKeywordsSourceNature PlantsYear2023
- Since biodiversity often increases ecosystem functioning, changes in tree species diversity could substantially influence terrestrial carbon cycling. Yet much less is known about the relationships between forest structural diversity (i.e., the number and physical arrangement of vegetation elements in a forest) and carbon cycling, and the factors that mediate these relationships. We capitalize on spaceborne lidar data from NASA's Global Ecosystem Dynamics Investigation (GEDI) and on-the-ground forest inventory and analysis (FIA) data from 1796 plots across the contiguous United States to...AuthorsErin T.H. Crockett, Jeff W. Atkins, Qinfeng Guo, Ge Sun, Kevin M. Potter, Scott Ollinger, Carlos A. Silva, Hao Tang, Christopher W. W. Woodall, Justin J. Holgerson, Jingfeng XiaoKeywordsSourceRemote Sensing of EnvironmentYear2023
- The present study compared seasonal changes in the concentrations of calcium oxalate (CaOx) crystals and total calcium (Ca) in the foliage of red spruce (Picea rubens Sarg.), white pine (Pinus strobus L.), black oak (Quercus velutina L.), and sugar maple (Acer saccharum Marshall) trees. Samples were collected from the same four replicate trees of each species starting in June 2014 through September 2015 for a total of six times for conifers and four times for hardwoods. Calcium oxalate was extracted from tissues using a method developed in our laboratory in 2015. The purity of the extracted...AuthorsRakesh Minocha, Stephanie LongKeywordsSourceFrontiers in Forests and Global ChangeYear2023
- Alaska yellow-cedar (Cupressus nootkatensis) is a softwood tree species native to the Pacific coast of Canada and is known to contain various biologically active extractive components. Extractives are nonstructural chemical compounds found within wood that are primarily responsible for the durability of the tree itself and can, in some species, fend off attacks from microbes, insects, and other agents. Durability in wood often translates to biological activity in the human body, and some extractive compounds have already been identified as being biologically active. Extractives of Alaska...AuthorsPhoebe Wagner, Gabriel Epstein, Brett Hinkforth, Doreen Mann, Roderquita MooreKeywordsSourceFPL-RN-422Year2023
- Many durable wood species contain extractives with biologically active chemical components that have potential to be used for the development of pharmaceuticals. For this study, extractive compounds from western redcedar (Thuja plicata) were separated by their relative polarities using liquid–liquid fractionation and characterized through gas chromatography–mass spectroscopy (GC–MS). Fractionation was successful at separating the components of western redcedar in a consistent manner, and GC–MS was able to identify the presence of various terpenoid compounds, primarily nezukone and thujaplic...AuthorsBrett Hinkforth, Gabriel Epstein, Phoebe Wagner, Doreen Mann, Roderquita MooreSourceFPL-RN-424Year2023
- Commonly the raw material round timber is reduced into smaller parts such as solid wood boards, sheets of veneer, strands, particles, and fibers for further manufacturing and processing. In following steps, the single wooden pieces are joined together by adhesive bonding to achieve the final structures such as various types of wood laminations or wood-based panels. This chapter describes the various mechanical connecting and adhesive bonding solutions. Different mechanical connector systems are introduced in theory and practice. A major part of the chapter is dedicated to wood adhesion and...AuthorsCharles R. Frihart, Johannes Konnerth, Andrea Frangi, Christian Gottlober, Robert Jockwer, Frederic PichelinKeywordsSourceChapter 14 in Springer Handbook of Wood Science and TechnologyYear2023
- Glue laminated timber (glulam) is an engineered wood product composed of wood laminations bonded together with durable adhesives. Glulam is versatile ranging from simple, straight beams to complex, curved structural members and are used in a variety of applications including residential and commercial construction where they are often exposed due to the timeless aesthetic of wood. Glulam beams are also resource-efficient and offer designers highly predictable structural and fire performance when used in accordance with design specifications. However, factory-cut or field modifications to...AuthorsLaura Hasburgh, Keith Bourne, David BarberKeywordsSourcePaper in World Conference on Timber EngineeringYear2023
- Timber structures decay over time with degradation in their structural integrity. Changing environmental conditions, varying loads, exposure to moisture or insect attacks lead to changes in their vibrational response behaviour. Here we present a low-cost device used as a triggered exciter to enable the monitoring of the structural integrity of timber bearers or even power poles in electricity networks. The actuation is initiated by a novel purpose-built, calibrated spring-loaded piezo-electric exciter. The device is connected to a fibre-optical network with optical accelerometers to...AuthorsSebastian Oberst, Shahrokh Sepehrirahnama, Can Nerse, Zourab Brodzeli, Joseph C.S. Lai, Mark E. Mankowski, Tye Atkinson, Rachel A. Arango, Grant T. Kirker, Theo EvansSourceIRG paper, IRG/WP 23-50380Year2023
- Sulfurized polyacrylonitrile (SPAN) is a promising cathode active material capable of suppressing lithium polysulfide dissolution in lithium−sulfur (Li−S) batteries. However, due to the low S content in SPAN, achieving a high SPAN areal loading without compromising specific capacity and cycling stability would be required. To address this challenge, we took advantage of the inherent porous structure of natural wood and engineered carbonized delignifed wood (CDW) frameworks using a delignification/low-temperature pyrolysis approach. The unique design of the SPAN-impregnated CDW (SPAN@CDW)...AuthorsSeyed Morteza Sabet, Nawraj Sapkota, Shailendra Chiluwal, Ting Zheng, Craig M. Clemons, Apparao M. Rao, Srikanth PillaKeywordsSourceACS Sustainable Chemistry & EngineeringYear2023