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Articles 211 - 240 of 411

Full-Text Articles in Forest Biology

1999 Lilley Cornett Woods Overstory Data, Ryan W. Mcewan, Julia I. Chapman, Robert N. Muller Jan 2017

1999 Lilley Cornett Woods Overstory Data, Ryan W. Mcewan, Julia I. Chapman, Robert N. Muller

Data Files: Big Everidge Hollow Permanent Plots

Data collected in 1999 on the overstory in the Big Everidge Hollow portion of the Lilley Cornett Woods Appalachian Ecological Research Station in southeastern Kentucky. Data key is provided in a supplemental file.

Accompanying photo by Ryan W. McEwan.

DOI: https://doi.org/10.26890/lcw.5pn95oc6d7


1989 Lilley Cornett Woods Overstory Data, Ryan W. Mcewan, Julia I. Chapman, Robert N. Muller Jan 2017

1989 Lilley Cornett Woods Overstory Data, Ryan W. Mcewan, Julia I. Chapman, Robert N. Muller

Data Files: Big Everidge Hollow Permanent Plots

Data collected in 1989 on the overstory in Big Everidge Hollow portion of the Lilley Cornett Woods Appalachian Ecological Research Station in southeastern Kentucky. Data key is provided in a supplemental file.

Accompanying photo by Ryan W. McEwan.

DOI: https://doi.org/10.26890/lcw.jt5ds3db92


Overstory 2017, Mitchell J. Kukla, Corey M. Kuminecz, Julia I. Chapman, Taylor M. Sparbanie, Katherine Schrader, Michelle N. Little, Keith E. Gilland, Ryan W. Mcewan Jan 2017

Overstory 2017, Mitchell J. Kukla, Corey M. Kuminecz, Julia I. Chapman, Taylor M. Sparbanie, Katherine Schrader, Michelle N. Little, Keith E. Gilland, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Overstory data (woody species ≥2.5 centimeters in diameter at breast height) collected in 2017 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.


Saplings 2017, Mitchell J. Kukla, Corey M. Kuminecz, Julia I. Chapman, Ryan W. Mcewan Jan 2017

Saplings 2017, Mitchell J. Kukla, Corey M. Kuminecz, Julia I. Chapman, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Sapling data (woody species >50 centimeters in height and <2.5 cm diameter at breast height) collected in 2017 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.


Invasion Dynamics Of The Exotic Liana Euonymus Fortunei (Turcz.) Hand.-Mazz. (Wintercreeper), Todd J. Rounsaville Jan 2017

Invasion Dynamics Of The Exotic Liana Euonymus Fortunei (Turcz.) Hand.-Mazz. (Wintercreeper), Todd J. Rounsaville

Theses and Dissertations--Biology

Elevated atmospheric CO2 has been implicated as a driver of increased liana abundance worldwide. Known as disturbance creators and beneficiaries, lianas possess the potential to significantly influence forest ecosystems. I investigated the early-invasion dynamics of Euonymus fortunei (wintercreeper), an evergreen liana that is invading forests in eastern North America, disrupting native plant communities and ecosystem functions.

Wintercreeper is widely cultivated as an ornamental groundcover, frequently invading natural areas via asexual stem growth. Invasion of remote natural areas is dependent upon seed transport and may occur less frequently. I examined the mechanisms of seed dormancy by conducting a ‘move-along’ experiment …


Residential Building Energy Conservation And Avoided Power Plant Emissions By Urban And Community Trees In The United States, David J. Nowak, Nathaniel Appleton, Alexis Ellis, Eric Greenfield Jan 2017

Residential Building Energy Conservation And Avoided Power Plant Emissions By Urban And Community Trees In The United States, David J. Nowak, Nathaniel Appleton, Alexis Ellis, Eric Greenfield

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Urban trees and forests alter building energy use and associated emissions from power plants by shading buildings, cooling air temperatures and altering wind speeds around buildings. Field data on urban trees were combined with local urban/community tree and land cover maps, modeling of tree effects on building energy use and pollutant emissions, and state energy and pollutant costs to estimate tree effects on building energy use and associated pollutant emissions at the state to national level in the conterminous United States. Results reveal that trees and forests in urban/community areas in the conterminous United States annually reduce electricity use by …


Native And Agricultural Forests At Risk To A Changing Climate In The Northern Plains, Linda A. Joyce, Gary Bentrup, Antony S. Cheng, Peter Kolb, Michele Schoeneberger, Justin Derner Jan 2017

Native And Agricultural Forests At Risk To A Changing Climate In The Northern Plains, Linda A. Joyce, Gary Bentrup, Antony S. Cheng, Peter Kolb, Michele Schoeneberger, Justin Derner

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Native and agricultural forests in the Northern Plains provide ecosystem services that benefit human society—diversified agricultural systems, forest-based products, and rural vitality. The impacts of recent trends in temperature and disturbances are impairing the delivery of these services. Climate change projections identify future stressors of greater impact, placing at risk crops, soils, livestock, biodiversity, and agricultural and forest-based livelihoods. While these native and agricultural forests are also a viable option for providing mitigation and adaptation services to the Northern Plains, they themselves must be managed in terms of climate change risks. Because agricultural forests are planted systems, the primary approaches …


Are Northeastern U.S. Forests Vulnerable To Extreme Drought?, Adam P. Coble, Matthew A. Vadeboncoeur, Z. Carter Berry, Katie A. Jennings, Cameron D. Mcintire, John L. Campbell, Lindsey E. Rustad, Pamela H. Temper, Heidi Asbjornsen Jan 2017

Are Northeastern U.S. Forests Vulnerable To Extreme Drought?, Adam P. Coble, Matthew A. Vadeboncoeur, Z. Carter Berry, Katie A. Jennings, Cameron D. Mcintire, John L. Campbell, Lindsey E. Rustad, Pamela H. Temper, Heidi Asbjornsen

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

In the Northeastern U.S., drought is expected to increase in frequency over the next century, and therefore, the responses of trees to drought are important to understand. There is recent debate about whether land-use change or moisture availability is the primary driver of changes in forest species composition in this region. Some argue that fire suppression from the early twentieth century to present has resulted in an increase in shade-tolerant and pyrophobic tree species that are drought intolerant, while others suggest precipitation variability as a major driver of species composition. From this debate, an emerging hypothesis is that mesophication and …


Executive Summary, Agroforestry: Enhancing Resiliency In U. S. Agricultural Landscapes Under Changing Conditions, Toral Patel-Weynand, Gary Bentrup, Michele M. Schoeneberger Jan 2017

Executive Summary, Agroforestry: Enhancing Resiliency In U. S. Agricultural Landscapes Under Changing Conditions, Toral Patel-Weynand, Gary Bentrup, Michele M. Schoeneberger

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Agroforestry, the intentional integration of trees and shrubs into crop and animal production systems, is being deployed to enhance productivity, profitability, and environmental stewardship of agricultural operations and lands across the United States. The full assessment at https://doi.org/10.2737/WO-GTR-96 and summarized here provides a science-based synthesis on the use of agroforestry for mitigation and adaptation services in the face of climatic variability and change. It provides technical input to land-use sector issues in the National Climate Assessment (NCA) and serves as a framework for including agroforestry systems in agricultural strategies to improve productivity and food security and to build resilience in …


Are Weevils Picky Eaters? Community Structure And Host Specificity Of Neotropical Saproxylic Beetles (Coleoptera: Curculionidae), Jhunior A. Morillo Jan 2017

Are Weevils Picky Eaters? Community Structure And Host Specificity Of Neotropical Saproxylic Beetles (Coleoptera: Curculionidae), Jhunior A. Morillo

Dissertations and Theses

Abstract Primary saproxylic beetles play a major role in forest nutrient cycling and making deadwood accessible to other decomposers. Understanding beetle host preferences and patterns of community assembly is critical for their conservation, and for predicting which species might become invasive. This project aims to investigate the ecological and host specificity, as well as the community composition of curculionids in a mosaic of old-growth (OG) and secondary forest on the Osa Peninsula, Costa Rica. The subfamily Scolytinae was expected to be the most species-rich and abundant. Ambrosia beetles were expected to have more generalist species than other curculionids. Old growth …


Modeling The Spread Of Sudden Oak Death Across A Heterogeneous Landscape In Redwood National Park Using A Spatially-Explicit Epidemiological Model, Laura A. Morgan Jan 2017

Modeling The Spread Of Sudden Oak Death Across A Heterogeneous Landscape In Redwood National Park Using A Spatially-Explicit Epidemiological Model, Laura A. Morgan

Cal Poly Humboldt theses and projects

The pathogen Phytophthora ramorum, the causal agent of Sudden Oak Death (SOD), is responsible for the deaths of millions of oak (Quercus spp.) and tanoak (Notholithocarpus densiflorus) trees in California and Oregon (USA). A recent infection in Redwood National Park (RNP) in California (USA) provided an opportunity to adapt an existing SOD model to assess the efficacy of current and proposed management strategies. A common method of SOD treatment includes killing both infected and uninfected hosts in the area of infection, as well as the area surrounding the infection to create buffers to account for undetected …


The Variation Of Productivity And Its Allocation Along A Tropical Elevation Gradient: A Whole Carbon Budget Perspective, Yadvinder Malhi, Cécile A. J. Girardin, Gregory R. Goldsmith, Christopher E. Doughty, Norma Salinas, Daniel B. Metcalfe, Walter Huaraca Huasco, Javier E. Silva-Espejo, Jhon Del Aguilla-Pasquell, Filio Farfán Amézquita, Luiz E.O.C. Aragão, Rossella Guerrieri, Françoise Yoko Ishida, Nur Bahar, William Farfan-Rios, Oliver L. Phillips, Patrick Meir, Miles Silman Oct 2016

The Variation Of Productivity And Its Allocation Along A Tropical Elevation Gradient: A Whole Carbon Budget Perspective, Yadvinder Malhi, Cécile A. J. Girardin, Gregory R. Goldsmith, Christopher E. Doughty, Norma Salinas, Daniel B. Metcalfe, Walter Huaraca Huasco, Javier E. Silva-Espejo, Jhon Del Aguilla-Pasquell, Filio Farfán Amézquita, Luiz E.O.C. Aragão, Rossella Guerrieri, Françoise Yoko Ishida, Nur Bahar, William Farfan-Rios, Oliver L. Phillips, Patrick Meir, Miles Silman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

  • Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation.

  • We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300 m elevation transect in Peru.

  • Low growth rates at high elevations appear primarily driven by low gross primary productivity (GPP), with little shift in either carbon use efficiency (CUE) or allocation of net primary productivity (NPP) between wood, fine roots and canopy. The lack of trend in …


Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr. Aug 2016

Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.

Biology Theses

Invasive plants often dominate novel habitats where they did not co-evolve with local species. Several hypotheses suggest mechanisms that explain increased exotic plant success, including 'novel weapons' and 'degraded mutualisms'. Japanese knotweed (Fallopia japonica) and European buckthorn (Rhamnus cathartica) are widespread plant invaders in North America that can dominate ecosystems. The goal of this study is to test whether these impacts are more consistent with novel weapons or degraded mutualism hypotheses. I examine tree seedling recruitment, (germination and initial survival) growth, (biomass) and mycorrhizal invasion (AMF content) as a function of F. japonica and R. cathartica …


Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson Jun 2016

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …


Herbaceous 2016, Julia I. Chapman, Keith E. Gilland, Ryan W. Mcewan May 2016

Herbaceous 2016, Julia I. Chapman, Keith E. Gilland, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Herbaceous vegetation data collected in 2016 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.


Seed Dispersal: A Tale Of Two Species, W. John Hayden Apr 2016

Seed Dispersal: A Tale Of Two Species, W. John Hayden

Biology Faculty Publications

Orchids have minute, dustlike seeds. In this respect, Goodyera pubescens (Downy Rattlesnake Plantain), the 2016 VNPS Wildflower of the Year, is a typical orchid. Like all other orchids, Goodyera seeds contain little more than a few embryonic cells enclosed in a thin seed coat. There are two advantages to small seed size in orchids: minute seeds can be produced in prodigious quantities, and they can disperse over great distances by wind.


Assessing How Disruption Of Methanogenic Communities And Their Syntrophic Relationships In Tidal Freshwater Marshes Via Saltwater Intrusion May Affect Ch4 Emissions, David J. Berrier, Scott C. Neubauer, Rima B. Franklin Jan 2016

Assessing How Disruption Of Methanogenic Communities And Their Syntrophic Relationships In Tidal Freshwater Marshes Via Saltwater Intrusion May Affect Ch4 Emissions, David J. Berrier, Scott C. Neubauer, Rima B. Franklin

Rice Rivers Center Research Symposium

Tidal freshwater wetlands (TFW), which lie at the interface of saltwater and freshwater ecosystems, are predicted to experience moderate salinity increases due to sea level rise. Increases in salinity generally suppress CH4 production, but it is uncertain to what extent elevated salinity will affect CH4 cycling in TFW. It is also unknown whether CH4 production will resume when freshwater conditions return. The ability to produce CH4 is limited to a monophyletic group of the Euryarchaeota phylum called methanogens (MG), who are limited to a small number of substrates (e.g., acetate, H2, and formate) produced from the breakdown of fermentation products. …


Global Synthesis Of The Classifications, Distributions, Benefits And Issues Of Terracing, Wei Wei, Die Chen, Lixin Wang, Stefani Daryanto, Liding Chen, Yang Yu, Yonglong Lu, Ge Sun, Tianjiao Feng Jan 2016

Global Synthesis Of The Classifications, Distributions, Benefits And Issues Of Terracing, Wei Wei, Die Chen, Lixin Wang, Stefani Daryanto, Liding Chen, Yang Yu, Yonglong Lu, Ge Sun, Tianjiao Feng

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

For thousands of years, humans have created different types of terraces in different sloping conditions, meant to mitigate flood risks, reduce soil erosion and conserve water. These anthropogenic landscapes can be found in tropical and subtropical rainforests, deserts, and arid and semiarid mountains across the globe. Despite the long history, the roles of and the mechanisms by which terracing improves ecosystem services (ESs) remain poorly understood. Using literature synthesis and quantitative analysis, the worldwide types, distributions, major benefits and issues of terracing are presented in this review. A key terracing indicator, defined as the ratio of different ESs under terraced …


Ecosystem Services Of Woody Crop Production Systems, Ronald S. Zalesny Jr., John A. Stanturf, Emile S. Gardiner, James H. Perdue, Timothy M. Young, David R. Coyle, William L. Headlee, Gary S. Bañuelos, Amir Hass Jan 2016

Ecosystem Services Of Woody Crop Production Systems, Ronald S. Zalesny Jr., John A. Stanturf, Emile S. Gardiner, James H. Perdue, Timothy M. Young, David R. Coyle, William L. Headlee, Gary S. Bañuelos, Amir Hass

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Short-rotation woody crops are an integral component of regional and national energy portfolios, as well as providing essential ecosystem services such as biomass supplies, carbon sinks, clean water, and healthy soils. We review recent USDA Forest Service Research and Development efforts from the USDA Biomass Research Centers on the provisioning of these ecosystem services from woody crop production systems. For biomass, we highlight productivity and yield potential, pest susceptibility, and bioenergy siting applications. We describe carbon storage in aboveground woody biomass and studies assessing the provision of clean and plentiful water. Soil protection and wildlife habitat are also mentioned, in …


Agroforestry Horizons: Experiences And Reflections: Report-Out, Steve Rasmussen Jan 2016

Agroforestry Horizons: Experiences And Reflections: Report-Out, Steve Rasmussen

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The USDA National Agroforestry Center (NAC) is charting a course for the next five years. As part of this process, NAC and the USDA Interagency Agroforestry Team hosted a meeting of leaders in the fields of agroforestry, agriculture, and forestry, from government, universities, and the private sector, to share experiences and insights on agroforestry opportunities and challenges. The meeting occurred on April 27th and 28th, 2016, in Washington, DC, and entailed presentations and discussions on current and potential roles of agroforestry in supporting water quality, soil health, economic diversification, food security, and pollinator/wildlife habitat. This report-out provides a summary of …


Riparian Trees And Aridland Streams Of The Southwestern United States: An Assessment Of The Past, Present, And Future, D. Max Smith, Deborah M. Finch Jan 2016

Riparian Trees And Aridland Streams Of The Southwestern United States: An Assessment Of The Past, Present, And Future, D. Max Smith, Deborah M. Finch

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Riparian ecosystems are vital components of aridlands within the southwestern United States. Historically, surface flows influenced population dynamics of native riparian trees. Many southwestern streams has been altered by regulation, however, and will be further affected by greenhouse warming. Our analysis of stream gage data revealed that decreases in volume of annual discharge and mean peak discharge and a shift to earlier peak discharge will occur in the Southern Rockies region of Colorado, New Mexico, and Utah. These changes will likely decrease rates of reproduction and survival of cottonwood (Populus fremontii and Populus deltoides ssp. wislizenii), Goodding's willow …


Review Of Broad-Scale Drought Monitoring Of Forests: Toward An Integrated Data Mining Approach, Steven P. Norman, Frank H. Koch, William W. Hargrove Jan 2016

Review Of Broad-Scale Drought Monitoring Of Forests: Toward An Integrated Data Mining Approach, Steven P. Norman, Frank H. Koch, William W. Hargrove

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Efforts to monitor the broad-scale impacts of drought on forests often come up short. Drought is a direct stressor of forests as well as a driver of secondary disturbance agents, making a full accounting of drought impacts challenging. General impacts can be inferred from moisture deficits quantified using precipitation and temperature measurements. However, derived meteorological indices may not meaningfully capture drought impacts because drought responses can differ substantially among species, sites and regions. Meteorology-based approaches also require the characterization of current moisture conditions relative to some specified time and place, but defining baseline conditions over large, ecologically diverse regions can …


Conditions Inside Fisher Dens During Prescribed Fires; What Is The Risk Posed By Spring Underburns?, Craig M. Thompson, Kathryn L. Purcell Jan 2016

Conditions Inside Fisher Dens During Prescribed Fires; What Is The Risk Posed By Spring Underburns?, Craig M. Thompson, Kathryn L. Purcell

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The use of spring prescribed fires to reduce accumulated fuel loads in western forests and facilitate the return of natural fire regimes is a controversial topic. While spring burns can be effective at reducing fuel loads and restoring heterogeneous landscapes, concerns exist over the potential impacts of unnaturally timed fires to native species. To protect native wildlife from disturbance during critical periods, limited operating periods (LOPs) are often implemented. However when LOPs for multiple species are combined into an integrated management plan, very few time windows for implementing prescribed fires remain. The use of spring burns is often effectively eliminated, …


Long-Term Impacts Of Fuel Treatments On Tree Growth And Aboveground Biomass Accumulation In Ponderosa Pine Forests Of The Northern Rocky Mountains, Kate A. Clyatt Jan 2016

Long-Term Impacts Of Fuel Treatments On Tree Growth And Aboveground Biomass Accumulation In Ponderosa Pine Forests Of The Northern Rocky Mountains, Kate A. Clyatt

Graduate Student Theses, Dissertations, & Professional Papers

In western North America, many low-elevation, dry forest types historically experienced frequent, low-severity fires. However, European settlement and fire suppression policies have contributed to over a century of fire exclusion, substantially altering forest structure and composition. There is considerable interest in restoring fire resilient characteristics to these forests through fuel reduction treatments. One limitation of current research on the impacts of fuel treatments is treatment longevity, as few studies have been able to quantify long-term responses to commonly applied treatments. This research evaluated tree growth and aboveground biomass responses 23 years after treatment in two silvicultural installations with different underburning …


Invasibility Of Three Major Non-Native Invasive Shrubs And Associated Factors In Upper Midwest U.S. Forest Lands, W. Keith Moser, Zhaofei Fan, Mark H. Hansen, Michael K. Crosby, Shirley X. Fan Jan 2016

Invasibility Of Three Major Non-Native Invasive Shrubs And Associated Factors In Upper Midwest U.S. Forest Lands, W. Keith Moser, Zhaofei Fan, Mark H. Hansen, Michael K. Crosby, Shirley X. Fan

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

We used non-native invasive plant data from the United States Forest Service’s Forest Inventory and Analysis (FIA) program, spatial statistical methods, and the space (cover class)-for-time approach to quantify the invasion potential and success (‘‘invasibility”) of three major invasive shrubs (multiflora rose, non-native bush honeysuckles, and common buckthorn) in broadly classified forest-type groups in seven Upper Midwest states. Smoothed maps of presence and cover percent showed a strong clustering pattern for all three invasive shrubs despite their different ranges. The species are clustered around major cities or urban areas (e.g., Chicago, Illinois, and Des Moines, Iowa), indicating the potential role …


Semiochemicals In The Natural History Of Southern Pine Beetle Dendroctonus Frontalis Zimmermann And Their Role In Pest Management, B. T. Sullivan Jan 2016

Semiochemicals In The Natural History Of Southern Pine Beetle Dendroctonus Frontalis Zimmermann And Their Role In Pest Management, B. T. Sullivan

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The southern pine beetle, Dendroctonus frontalis Zimmermann is generally considered to be one of the most significant biotic mortality agents of pines within North America, with a range stretching from New England to eastern Texas and from Arizona south to Nicaragua. As with other aggressive pine beetles, it relies on semiochemicals for coordinating the mass attacks necessary for colonization of healthy pines. Over the past 50 years its chemical ecology has received extensive study aimed at development of effective and practical semiochemical-based management strategies which might replace the destructive and costly techniques in practice. I review the literature on the …


A Forest Vulnerability Index Based On Drought And High Temperatures, David Mildrexler, Zhiqiang Yang, Warren B. Cohen, David M. Bell Jan 2016

A Forest Vulnerability Index Based On Drought And High Temperatures, David Mildrexler, Zhiqiang Yang, Warren B. Cohen, David M. Bell

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Increasing forest stress and tree mortality has been directly linked to combinations of drought and high temperatures. The climatic changes expected during the next decades – large increases in mean temperature, increased heat waves, and significant long-term regional drying in the western USA – will likely increase chronic forest stress and mortality. The aim of this research is to develop and apply a new forest vulnerability index (FVI) associated with drought and high temperatures across the Pacific Northwest region (PNW; Oregon and Washington) of the USA during the MODIS Aqua era (since 2003). Our technique incorporates the alterations to canopy …


Contributing Factors For Drought In United States Forest Ecosystems Under Projected Future Climates And Their Uncertainty, Charles H. Luce, James M. Vose, Neil Pederson, John Campbell, Connie Millar, Patrick Kormos, Ross Woods Jan 2016

Contributing Factors For Drought In United States Forest Ecosystems Under Projected Future Climates And Their Uncertainty, Charles H. Luce, James M. Vose, Neil Pederson, John Campbell, Connie Millar, Patrick Kormos, Ross Woods

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Observations of increasing global forest die-off related to drought are leading to more questions about potential increases in drought occurrence, severity, and ecological consequence in the future. Dry soils and warm temperatures interact to affect trees during drought; so understanding shifting risks requires some understanding of changes in both temperature and precipitation. Unfortunately, strong precipitation uncertainties in climate models yield substantial uncertainty in projections of drought occurrence. We argue that disambiguation of drought effects into temperature and precipitation-mediated processes can alleviate some of the implied uncertainty. In particular, the disambiguation can clarify geographic diversity in forest sensitivity to multifarious drivers …


Improved Bulk Density Of Bamboo Pellets As Biomass For Energy Production, Zhijia Liu, Bingbing Mi, Zehui Jiang, Benhua Fei, Zhiyong Cai, Xing'e Liu Jan 2016

Improved Bulk Density Of Bamboo Pellets As Biomass For Energy Production, Zhijia Liu, Bingbing Mi, Zehui Jiang, Benhua Fei, Zhiyong Cai, Xing'e Liu

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

To the best of our knowledge, there is the lack of sufficient information concerning bamboo pellets. In the preliminary research, bamboo pellets showed a low bulk density which could not meet requirement of Pellet Fuels Institute Standard Specification for Residential/Commercial Densified (PFI). To improve its bulk density, pellets were manufactured using mixtures of bamboo and pine particles and the properties were investigated. It was found that adding pine particles to bamboo particles was an effective way to improve bulk density of bamboo pellets. When adding 40% pine particles to bamboo particles, bulk density of pellets increased from 0.54 …


Pronghorn Habitat Suitability In The Texas Panhandle, Nathan P. Duncan, Samantha S. Kahl, Shawn S. Gray, Christopher J. Salice, Richard D. Stevens Jan 2016

Pronghorn Habitat Suitability In The Texas Panhandle, Nathan P. Duncan, Samantha S. Kahl, Shawn S. Gray, Christopher J. Salice, Richard D. Stevens

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Habitat quality is an important factor that can greatly affect wildlife populations. Pronghorn (Antilocapra americana) habitat in the Texas Panhandle, USA has been lost through growth of human settlements and agricultural lands. We determined the most pertinent environmental variables affecting habitat selection using multiple methods, including a search of peer-reviewed literature, expert opinion ranking, and habitat suitability modeling. We determined quality and extent of pronghorn habitat in the Texas Panhandle using the MAXENT modeling environment to build a presence-only habitat suitability model based on global positioning system (GPS) locations collected via aerial surveys. Our habitat suitability model indicated …