Other Forestry and Forest Sciences Commons^™

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

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 …

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

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 …

Pyrodiversity Promotes Avian Diversity Over The Decade Following Forest Fire, Morgan W. Tingley, Viviana Ruiz-Gutierrez, Robert L. Wilkerson, Christine A. Howell, Rodney B. Siegel

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

An emerging hypothesis in fire ecology is that pyrodiversity increases species diversity.We test whether pyrodiversity—defined as the standard deviation of fire severity—increases avian biodiversity at two spatial scales, and whether and how this relationship may change in the decade following fire. We use a dynamic Bayesian community model applied to a multi-year dataset of bird surveys at 1106 points sampled across 97 fires in montane California. Our results provide strong support for a positive relationship between pyrodiversity and bird diversity. This relationship interacts with time since fire, with pyrodiversity having a greater effect on biodiversity at 10 years post-fire than …

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 …

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

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

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, …

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 …

Diseases Of Trees In The Great Plains, Aaron D. Bergdahl, Alison Hill, Gerard C. Adams, Rachel A. Allison, John A. Appel, John Ball, James T. Blodgett, Kelly S. Burns, Whitney Cranshaw, Kelsey L. Dunnell, Mark L. Gleason, Mark O. Harrell, Thomas C. Harrington, Marcus B. Jackson, William R. Jacobi, Jennifer Juzwik, Megan M. Kennwlly, Les Koch, Jared M. Leboldus, Phillip A. Mason, Douglas L. Mcnew, Judith O'Mara, Hayley M. Nelson, Nicole Opbroek, Michael E. Ostry, Scott C. Redlin, Glen R. Stanosz, Laurie J. Stepanek, Ned Tisserat, Timothy C. Todd, James A. Walla, James J. Worrall, Simeon Wright

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

Hosts, distribution, symptoms and signs, disease cycle, and management strategies are described for 84 hardwood and 32 conifer diseases in 56 chapters. Color illustrations are provided to aid in accurate diagnosis. A glossary of technical terms and indexes to hosts and pathogens also are included.

Scope

The purpose of this handbook is to assist users in diagnosing tree diseases and reducing their impact. Included are the most damaging diseases, along with some that are the subject of frequent inquiry although of minor importance. The diseases included were those encountered primarily on trees in conservation plantings such as windbreaks, farmstead plantings, …

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 …

Demography And Disease Of The Rare Shrub Buckleya Distichophylla (Santalaceae) In Northeastern Tennessee, William Seth Ratliff

Undergraduate Honors Theses

Piratebush (Buckleya distichophylla (Nutt.) Torr.) is a rare, hemiparasitic shrub with the only extant populations in western North Carolina, northeastern Tennessee, and southwestern Virginia. The preferred natural hosts of piratebush, Carolina and eastern hemlocks, have seen sharp declines over the last decade due to the invasive hemlock woolly adelgid. Virginia pine, another important host of piratebush, is also susceptible to disease, specifically Cronartium appalachianum, a rust fungus for which piratebush is the secondary host. This study described and analyzed current demographic parameters of three Tennessee piratebush populations. Additionally, spatial patterns of disease and demographic characters were analyzed. These …

Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar

Student Theses 2015-Present

This thesis compares and explains the advantages aquaponics farming has over modern industrial intensive farming. Through a comparison natural capital usage, conservation, recycling and cost, the thesis advocates for the expansion of aquaponics usage in urban settings. The thesis also explains the history of intensive farming and aquaponics in America, the science of how aquaponics operates, the economic and environmental costs of modern intensive farming versus aquaponics farming, and the social implications of aquaponics. Lastly, I propose a policy that reallocates farm subsidies by modifying the Farm Bill. Then I propose policies that support creating a new standard of farm …

Environmental Data: Soil Moisture, Julia I. Chapman, Eric B. Borth, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Volumetric soil water content measured on May 2, 2015 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Herbaceous 2015, Julia I. Chapman, Margaret E. Maloney, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Herbaceous vegetation data collected in 2015 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

The Linkages Between Photosynthesis, Productivity, Growth And Biomass In Lowland Amazonian Forests, Yadvinder Malhi, Christopher E. Doughty, Gregory R. Goldsmith, Daniel B. Metcalfe, Cécile A.J. Girardin, Toby R. Marthews, Jhon Del Aguila-Pasquel, Luiz E.O.C. Aragão, Alejandro Araujo-Murakami, Paulo Brando, Antonino C.L. Da Costa, Javier E. Silva-Espejo, Filio Farfán Amézquita, David R. Galbraith, Carlos A. Quesada, Wanderley Rocha, Norma Salinas-Revilla, Divino Silvério, Patrick Meir, Oliver L. Phillips

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Amazonian forests spanning gradients in seasonal water deficit and soil fertility. Using the largest data set assembled to date, ten sites in three countries all studied with a standardized methodology, we find that (i) gross primary productivity (GPP) has a simple relationship with seasonal water deficit, but …

Effects Of Drought On Forests And Rangelands In The United States: A Comprehensive Science Synthesis, James M. Vose, James S. Clark, Charles H. Luce, Toral Patel-Weynand

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

This assessment provides input to the reauthorized National Integrated Drought Information System (NIDIS) and the National Climate Assessment (NCA), and it establishes the scientific foundation needed to manage for drought resilience and adaptation. Focal areas include drought characterization; drought impacts on forest processes and disturbances such as insect outbreaks and wildfire; and consequences on forest and rangeland values. Drought can be a severe natural disaster with substantial social and economic consequences. Drought becomes most obvious when large-scale changes are observed; however, even moderate drought can have long-lasting impacts on the structure and function of forests and rangelands without these obvious …

Biological Invasion Hotspots: A Trait-Based Perspective Reveals New Sub-Continental Patterns, Basil V. Iannone Iii, Kevin M. Potter, Qinfeng Guo, Andrew M. Liebhold, Bryan C. Pijanowski, Christopher M. Oswalt, Songlin Fei

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

Invader traits (including plant growth form) may play an important, and perhaps overlooked, role in determining macroscale patterns of biological invasions and therefore warrant greater consideration in future investigations aimed at understanding these patterns. To assess this need, we used empirical data from a national-level survey of forest in the contiguous 48 states of the USA to identify geographic hotspots of forest plant invasion for three distinct invasion characteristics: invasive species richness, trait richness (defined as the number of the five following plant growth forms represented by the invasive plants present at a given location: forbs, grasses, shrubs, trees, and …

Striking The Balance: Challenges And Perspectives For The Protected Areas Network In Northeastern European Russia, Svetlana V. Degteva, Vasily I. Ponomarev, Sasha W. Eisenman, Vyacheslav Dushenkov

Publications and Research

Increasing anthropogenic pressure on the largest remaining tracts of old-growth boreal forest in Europe necessitates additional conservation of ecosystems and biodiversity in northeastern European Russia. In a regional network comprising 8 % of the Nenets Autonomous District and 13.5 % of the Komi Republic, 248 areas have varying protected statuses as state nature reserves (zapovedniks), national parks, reserves/sanctuaries (zakazniks), or natural monuments. Due to increased natural resource extraction in this relatively pristine area, designation of additional protected areas is critical for the protection of key ecological sites. The history of ecological preservation in these regions is herein described, and recent …

A Win-Win On Agricultural Lands: Creating Wildlife Habitat Through Agroforestry, Gary Bentrup

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

With increasing demands from society for limited resources, agroforestry will likely be one source of solutions as people find it increasingly necessary to achieve multiple social, economic, and ecological objectives on the same plot of land. Indications are that this is a growing field, so wildlife biologists of the future may want to consider incorporating agroforestry into their career development.

Fact Or Fiction: Random Mating In Field Populations Of Western Corn Rootworm (Diabrotica Virgifera Virgifera Leconte) Emerging On Bt And Refuge Corn Plants, Steven Joel Smith

Open Access Theses

The western corn rootworm, or WCR, (Diabrotica virgifera virgifera LeConte) is the most significant pest of field corn (Zea mays) in the United States, and has recently expanded its range into Europe. Since 2004, hybrid corn containing Bt toxins targeting the corn rootworm complex have been heavily adopted and are now the primary control measure for this pest in North American corn production. ^ The evolution of resistance is an ongoing concern, and to ensure Bt products will retain their usefulness, insect resistance management (IRM) tactics using various refuge structures have been adopted. One of the key …

Herbaceous 2014, Julia I. Chapman, Keith E. Gilland, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Herbaceous vegetation data collected in 2014 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

A New Metric For Quantifying Burn Severity: The Relativized Burn Ratio, Sean A. Parks, Gregory K. Dillon, Carol Miller

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

Satellite-inferred burn severity data have become increasingly popular over the last decade for management and research purposes. These data typically quantify spectral change between pre-and post-fire satellite images (usually Landsat). There is an active debate regarding which of the two main equations, the delta normalized burn ratio (dNBR) and its relativized form (RdNBR), is most suitable for quantifying burn severity; each has its critics. In this study, we propose and evaluate a new Landsat-based burn severity metric, the relativized burn ratio (RBR), that provides an alternative to dNBR and RdNBR. For 18 fires in the western US, we compared the …

Temporal Fluctuation Scaling In Populations And Communities, Michael Kalyuzhny, Yishai Schreiber, Rachel Chocron, Curtis H. Flather, Ronen Kadmon, David A. Kessler, Nadav M. Shnerb

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

Taylor’s law, one of the most widely accepted generalizations in ecology, states that the variance of a population abundance time series scales as a power law of its mean. Here we reexamine this law and the empirical evidence presented in support of it. Specifically, we show that the exponent generally depends on the length of the time series, and its value reflects the combined effect of many underlying mechanisms. Moreover, sampling errors alone, when presented on a double logarithmic scale, are sufficient to produce an apparent power law. This raises questions regarding the usefulness of Taylor’s law for understanding ecological …

Long-Term Changes In Four Plant Communities Along An Elevational Gradient In The Front Range Of Colorado, Gregory J. Sproull

Electronic Theses and Dissertations

We surveyed four plant communities along an elevational gradient in the Front Range of the Colorado Rocky Mountains for long-term overstory and understory changes. Our results were compared to those found in 1981 and 1996. We evaluated changes in succession, elevational species migration and range expansion, community diversity, and composition. We related temporal floristic shifts to prior literature on disturbance history at each site. Over time, all communities changed significantly, though in different manners. This analysis shows that plant communities are changing in dynamic and idiosyncratic ways that correspond to individualistic distribution shifts. Moreover, we exhibit the necessity of comprehensively …

Nitrogen And Carbon Dynamics In Prairie Vegetation Strips Across Topographical Gradients In Mixed Central Iowa Agroecosystems, Marlin Perez-Suarez, Michael J. Castellano, Randall Kolka, Heidi Asbjornsen, Matthew J. Helmers

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

Reductions of nitrogen (N) export from agricultural lands because of changes in specific N stocks andfluxes by incorporation of small amounts of prairie vegetation strips (PVS) are poorly understood. Theprimary objective of this study was to evaluate the effect of the presence and topographical position of PVSon soil and plant carbon (C) and N stocks relative to annual crop and native prairie vegetation. The studywas implemented within three small adjacent watersheds, treated with one of the following cover types:(1) 100% row-crop agriculture (CROP); (2) 20% prairie vegetation (PVS) distributed along the contouracross three topographical positions: upslope, sideslope and footslope position; …

Recovery Of Wolverines In The Western United States: Recent Extirpation And Recolonization Or Range Retraction And Expansion?, Kevin S. Mckelvey, Keith B. Aubry, Neil J. Anderson, Anthony P. Clevenger, Jeffrey P. Copeland, Kimberley S. Heinemeyer, Robert M. Iman, John R. Squires, John S. Waller, Kristine L. Pilgrim, Michael K. Schwartz

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

Wolverines were greatly reduced in number and possibly extirpated from the contiguous United States (U.S.) by the early 1900s. Wolverines currently occupy much of their historical range in Washington, Idaho, Montana, and Wyoming, but are absent from Utah and only single individuals are known to occur in California and Colorado. In response, the translocation of wolverines to California and Colorado is being considered. If wolverines are to be reintroduced, managers must identify appropriate source populations based on the genetic affinities of historical and modern wolverine populations. We amplified the mitochondrial control region of 13 museum specimens dating from the late …

Housing Development Erodes Avian Community Structure In U.S. Protected Areas, Eric M. Wood, Anna M. Pidgeon, Volker C. Radeloff, David Helmers, Patrick D. Culbert, Nicholas S. Keuler, Curtis H. Flather

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

Protected areas are a cornerstone for biodiversity conservation, but they also provide amenities that attract housing development on inholdings and adjacent private lands. We explored how this development affects biodiversity within and near protected areas among six ecological regions throughout the United States. We quantified the effect of housing density within, at the boundary, and outside protected areas, and natural land cover within protected areas, on the proportional abundance and proportional richness of three avian guilds within protected areas. We developed three guilds from the North American Breeding Bird Survey, which included Species of Greatest Conservation Need, land cover affiliates …

Performance Of Species Richness Estimators Across Assemblage Types And Survey Parameters, Gordon C. Reese, Kenneth R. Wilson, Curtis H. Flather

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

Aim A raw count of the species encountered across surveys usually underestimates species richness. Statistical estimators are often less biased. Nonparametric estimators of species richness are widely considered the least biased, but no particular estimator has consistently performed best. This is partly a function of estimators responding differently to assemblage-level factors and survey design parameters. Our objective was to evaluate the performance of raw counts and nonparametric estimators of species richness across various assemblages and with different survey designs.

Location We used both simulated and published field data.

Methods We evaluated the bias, precision and accuracy of raw counts and …