Treesearch
Displaying 16,871 - 16,880 of 64,690 Publications- Durante un periodo de aproximadamente 20 años, el Instituto Internacional de Dasonomía Tropical y sus colaboradores desarrollaron e implementaron un plan de instalaciones que abarcaba tanto las instalaciones nuevas, como las restauradas. Entre las instalaciones restauradas, el edificio histórico de la sede institucional recibió una Certificación Dorada por Liderazgo en el Diseño de Eficiencia Energética y Ambiental (LEED, por sus siglas en inglés) y felicitaciones de la Oficina Estatal de Preservación Histórica por la forma en que se llevó a cabo la restauración. Es inusual que los...AuthorsAriel Lugo, J. RullanKeywordsSourceResearch Note IITF-RN-2 (Spanish)Year2015
- Fringing marshes are abundant ecosystems that dominate the New England coastline. Despite their abundance, very little baseline data is available from them and few studies have documented the ecosystems services that they provide. This information is important for conservation efforts as well as for an increased understanding of how fringing marshes function compared to larger marsh meadow systems. Benthic infaunal invertebrates were sampled from cores collected from Spartina alterniflora-dominated low marsh, Spartina patens-dominated high marsh, and Phragmites australis-invaded high marsh...AuthorsRichard A. MacKenzie, Michele Dionne, Jeremy Miller, Michael Haas, Pamela A. MorganKeywordsSourceEstuaries and Coasts. 38(4): 1317-1334Year2015
- In this study, α-cellulose fibers reinforced green biocomposites based on polyhydroxybutyrate (PHB) and the copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were prepared and characterized. The α-cellulose fibers were isolated from at-risk intermountain lodgepole pine wood by successive removal of extractives, lignin and hemicellulose. Grafting of PHB or PHBV onto cellulose was conducted using reactive extrusion with dicumyl peroxide free radical initiation at high temperature. It is postulated that the grafted copolymers at the interfaces of cellulose and the polymer matrix...AuthorsLiqing Wei, Nicole M. Stark, Armando G. McDonaldSourceGreen Chemistry, Vol. 17(10)Year2015
- We present an aerial mapping method to efficiently and effectively identify seed clusters of the invasive tree, Ailanthus altissima (Mill.) Swingle across deciduous forest landscapes in the eastern United States. We found that the ideal time to conduct aerial digital surveys is early to middle winter, when Ailanthus seed clusters persist and there is no interfering leaf cover. Because of the color, quantity, and seedpod arrangement, female seed-bearing Ailanthus trees are very conspicuous from the air. With use of digital sketchmapping technology from helicopters, seed-bearing Ailanthus...AuthorsJoanne Rebbeck, Aaron Kloss, Michael Bowden, Cheryl Coon, Todd Hutchinson, Louis Iverson, Greg GuessSourceForest Science. 61(6): 1068-1078.Year2015
- Humid tropical forest soils are characterized by warm temperatures, abundant rainfall, and high rates of biological activity that vary considerably in both space and time. These conditions, together with finely textured soils typical of humid tropical forests lead to periodic low redox conditions, even in well-drained upland environments. The relationship between redox and biogeochemical processes has been studied for decades in saturated environments like wetlands and sediments, but much less is known about redox dynamics in upland soils. The goal of this study was to understand the...AuthorsDaniel Liptzin, Whendee L. SilverSourceEcosphereYear2015
- It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide1. Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities2. However, subsequent experimental tests produced mixed results3–13. Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilienc...AuthorsForest Isbell, Dylan Craven, John Connolly, Michel Loreau, Bernhard Schmid, Carl Beierkuhnlein, T. Martijn Bezemer, Catherine Bonin, Helge Bruelheide, Enrica de Luca, Anne Ebeling, John N. Griffin, Qinfeng Guo, Yann Hautier, Andy Hector, Anke Jentsch, Jurgen Kreyling, Vojtech Lanta, Pete Manning, Sebastian T. Meyer, Akira S. Mori, Shahid Naeem, Pascal A. Niklaus, H. Wayne Polley, Peter B. Reich, Christiane Roscher, Eric W. Seabloom, Melinda D. Smith, Madhav P. Thakur, David Tilman, Benjamin F. Tracy, Wim H. van der Putten, Jasper van Ruijven, Alexandra Weigelt, Wolfgang W. Weisser, Brian Wilsey, Nico EisenhauerSourceNatureYear2015
- Light use efficiency (LUE) is a key biophysical parameter characterizing the ability of plants to convert absorbed light to carbohydrate. However, the environmental regulations on LUE, especially moisture stress, are poorly understood, leading to large uncertainties in primary productivity estimated by LUE models. The objective of this study is to investigate the effects of moisture stress on LUE for a wide range of ecosystems on daily, 8 day, and monthly scales. Using the FLUXNET and Moderate Resolution Imagine Spectroradiometer data, we evaluated moisture stress along the soil-plant-atmos...AuthorsYulong Zhang, Conghe Song, Ge Sun, Lawrence E. Band, Asko Noormets, Quanfa ZhangSourceJournal of Geophysical Research: BiogeosciencesYear2015
- Aims. Our objective was to assess the impacts of water table position and plant functional groups on peatland extracellular enzyme activity (EEA) framed within the context of the enzymic latch hypothesis. Methods. We utilized a full factorial experiment with 2 water table (WT) treatments (high and low) and 3 plant functional groups (PFG: Ericaceae, sedge, Ericaceae and sedge unmanipulated) in twenty-four 1 m3 intact peatland mesocosms. We measured bulk peat and porewater phase oxidative and hydrolytic enzyme activities monthly from June - October 2012. We also measured physical and...AuthorsKarl J. Romanowicz, Evan Kane, Lynette Potvin, Aleta L. Daniels, Randy Kolka, Erik LilleskovKeywordsSourcePlant and Soil. 397(1-2): 371-386.Year2015
Fertility-dependent effects of ectomycorrhizal fungal communities on white spruce seedling nutrition
Ectomycorrhizal fungi (EcMF) typically colonize nursery seedlings, but nutritional and growth effects of these communities are only partly understood. To examine these effects, Picea glauca seedlings collected from a tree nursery naturally colonized by three dominant EcMF were divided between fertilized and unfertilized treatments. After one growing season seedlings were harvested, ectomycorrhizas identified using DNA sequencing, and seedlings analyzed for leaf nutrient concentration and content, and biomass parameters. EcMF community structure–nutrient interactions were tested using...AuthorsAlistair J. H. Smith, Lynette Potvin, Erik LilleskovKeywordsSourceMycorrhiza. 25(8): 649-662.Year2015- Pre-dispersal seed predation (PDSP) is commonly observed in woody plants, and recognized as a driver of seed production variability that is critical for successful regeneration. Earlier studies on PDSP and its determinants were mostly species specific, with community- level PDSP rarely estimated; and the interactions between the temporal variability of seed production and PDSP remain elusive. In this study, the community seed rain of woody plants in a mixed evergreen-deciduous broadleaf forest was monitored for seven years. We examined predation on collected seeds and analyzed the determina...AuthorsYue Xu, Zehao Shen, Daoxin Li, Qinfeng GuoSourcePLOS ONEYear2015