Ecology and Evolutionary Biology Commons^™

Prescribed Fire Alters Structure And Composition Of A Mid-Atlantic Oak Forest Up To Eight Years After Burning, Cody L. Dems, Alan H. Taylor, Erica A. H. Smithwick, Jesse K. Kreye, Margot W. Kaye

Aspen Bibliography

Background

Prescribed fire in Eastern deciduous forests has been understudied relative to other regions in the United States. In Pennsylvania, USA, prescribed fire use has increased more than five-fold since 2009, yet forest response has not been extensively studied. Due to variations in forest composition and the feedback between vegetation and fire, Pennsylvania deciduous forests may burn and respond differently than forests across the eastern US. We measured changes in forest structure and composition up to eight years after prescribed fire in a hardwood forest of the Ridge and Valley region of the Appalachian Mountains in central Pennsylvania.

Results

Within …

Microplastics: Nacogdoches County’S Hidden Threat, Jordan Stanford, Sydney Matlock, Courtney Sims, Samantha Montes

Undergraduate Research Conference

Microplastics and their threat to marine environments are well known, but studies in freshwater environments are few and far between. Microplastics can be created by the breaking down of plastics or in the process of making plastics. They affect biological lifeforms in a multitude of ways, water temperature, permeability of the sediment. Pollution in Texas waterways have motivated groups like the Environmental Protection Agency, Trash Free Texas, and Environment Texas to get involved. The objectives of this study are two analyze Bonita and La Nana Bayou for microplastic presence and to educate and create awareness for Nacogdoches County on microplastics. …

Widespread Mortality Of Trembling Aspen (Populus Tremuloides) Throughout Interior Alaskan Boreal Forests Resulting From A Novel Canker Disease, Roger W. Ruess, Loretta M. Winton, Gerard C. Adams

Aspen Bibliography

Over the past several decades, growth declines and mortality of trembling aspen throughout western Canada and the United States have been linked to drought, often interacting with outbreaks of insects and fungal pathogens, resulting in a “sudden aspen decline” throughout much of aspen’s range. In 2015, we noticed an aggressive fungal canker causing widespread mortality of aspen throughout interior Alaska and initiated a study to quantify potential drivers for the incidence, virulence, and distribution of the disease. Stand-level infection rates among 88 study sites distributed across 6 Alaska ecoregions ranged from < 1 to 69%, with the proportion of trees with canker that were dead averaging 70% across all sites. The disease is most prevalent north of the Alaska Range within the Tanana Kuskokwim ecoregion. Modeling canker probability as a function of ecoregion, stand structure, landscape position, and climate revealed that smaller-diameter trees in older stands with greater aspen basal area have the highest canker incidence and mortality, while younger trees in younger stands appear virtually immune to the disease. Sites with higher summer vapor pressure deficits had significantly higher levels of canker infection and mortality. We believe the combined effects of this novel fungal canker pathogen, drought, and the persistent aspen leaf miner outbreak are triggering feedbacks between carbon starvation and hydraulic failure that are ultimately driving widespread mortality. Warmer early-season temperatures and prolonged late summer drought are leading to larger and more severe wildfires throughout interior Alaska that are favoring a shift from black spruce to forests dominated by Alaska paper birch and aspen. Widespread aspen mortality fostered by this rapidly spreading pathogen has significant implications for successional dynamics, ecosystem function, and feedbacks to disturbance regimes, particularly on sites too dry for Alaska paper birch.

Historic Declines In Growth Portend Trembling Aspen Death During A Contemporary Leaf Miner Outbreak In Alaska, Melissa A. Boyd, Logan T. Berner, Adrianna C. Foster, Scott J. Goetz, Brendan M. Rogers, Xanthe J. Walker, Michelle C. Mack

Aspen Bibliography

Climate change-driven droughts and insect outbreaks are becoming more frequent and widespread, increasing forest vulnerability to mortality. By addressing the impacts of climate and insects on tree growth preceding death, we can better understand tree mortality risk under a changing climate. Here, we used tree stature and interannual growth (basal area increment; BAI) to assess processes leading to trembling aspen (Populus tremuloides) survival or mortality during an unprecedented leaf miner (Phyllocnistis populiella) outbreak in boreal North America. We identified eight sites (22 plots) in the longest running forest monitoring network in Alaska, spanning ~350 km of …

Pando: Charismatic Megaflora And The Populus Paradox, Paul C. Rogers, Lance Oditt

Aspen Bibliography

Within the field of landscape ecology, the Pando aspen grove on the Fishlake National Forest of Utah is legendary—and it is in danger of dying from hotter, drier temperatures and other threats. Pando is one of the largest and oldest known still-living organisms on Earth. Quaking aspen are an important tree species in Greater Yellowstone and the Rocky Mountain West. Enjoy this essay written by a scientist who studies Pando and a photographer who celebrates this arboreal mega-being.

The Annual Rhythmic Differentiation Of Populus Davidiana Growth–Climate Response Under A Warming Climate In The Greater Hinggan Mountains, Ruixin Yun, Yuting Jin, Junxia Li, Zhenju Chen, Zhaoyang Lyu, Ying Zhao, Di Cui

Aspen Bibliography

The stability and balance of forest ecosystems have been seriously affected by climate change. Herein, we use dendrochronological methods to investigate the radial growth and climate response of pioneer tree species in the southern margin of cold temperate coniferous forest based on Populus davidiana growing on the Greater Hinggan Mountains in northeastern China. Correlations of P. davidiana growth with temperature and precipitation in a year (October–September) were rhythmically opposed: while temperatures in previous October–June (winter and spring) and in May–September (growing season) respectively inhibited and promoted radial growth on P. davidiana (p < 0.01), precipitation in the same periods respectively promoted and inhibited of growth (p < 0.01). High temperature or less rain/snow in winter and early spring, and low temperature or excess rainfall in summer, are inconducive to P. davidiana growth and vice versa …

Geographic Distribution: Eleutherodactylus Coqui (Common Coqui). Usa: Florida., Louis A. Somma

Papers in Herpetology

A geographic interception record for Eleutherodactylus coqui in Suwanee County, Florida.

Geographic Distribution: Iguana Iguana (Green Iguana): Usa: Florida., Louis A. Somma, Mark T. Bailey

Papers in Herpetology

A geographic distribution record for Iguana iguana in Marion County, Florida.

Improved Boreal Forest Wildfire Fuel Type Mapping In Interior Alaska Using Aviris-Ng Hyperspectral Data, Christopher William Smith, Santosh K. Panda, Uma Suren Bhatt, Franz J. Meyer

Aspen Bibliography

In Alaska the current wildfire fuel map products were generated from low spatial (30 m) and spectral resolution (11 bands) Landsat 8 satellite imagery which resulted in map products that not only lack the granularity but also have insufficient accuracy to be effective in fire and fuel management at a local scale. In this study we used higher spatial and spectral resolution AVIRIS-NG hyperspectral data (acquired as part of the NASA ABoVE project campaign) to generate boreal forest vegetation and fire fuel maps. Based on our field plot data, random forest classified images derived from 304 AVIRIS-NG bands at Viereck …

European Aspen With High Compared To Low Constitutive Tannin Defenses Grow Taller In Response To Anthropogenic Nitrogen Enrichment, Franziska Bandau, Benedicte Riber Albrectsen, Kathryn M. Robinson, Michael J. Gundale

Aspen Bibliography

Boreal forests receive nitrogen-(N)-enrichment via atmospheric deposition and industrial fertilization. While it is known that N-enrichment can intensify interactions with natural antagonists, it remains poorly understood how genetic variability in plant defense chemistry can affect biotic interactions and height growth in N-enriched environments. We grew replicates of five low- and high-tannin Populus tremula genotypes, respectively, under three N-treatments (ambient, 15, and 150 kg N ha−1 yr−1). We assessed shoot blight occurrence (i.e. symptoms caused by Venturia fungi) during four growing seasons, and tree height growth during the same period. Damage by Venturia spp. increased with N-addition during all years, likely …

76-Year Decline And Recovery Of Aspen Mediated By Contrasting Fire Regimes: Long-Unburned, Infrequent And Frequent Mixed-Severity Wildfire, Cerena J. Brewen, John-Pascal Berrill, Martin W. Ritchie, Kevin Boston, Christa M. Dagley, Bobette Jones, Michelle Coppoletta, Coye L. Burnett

Aspen Bibliography

Quaking aspen (Populus tremuloides) is a valued, minor component on northeastern California landscapes. It provides a wide range of ecosystem services and has been in decline throughout the region for the last century. This decline may be explained partially by the lack of fire on the landscape due to heavier fire suppression, as aspen benefit from fire that eliminates conifer competition and stimulates reproduction through root suckering. However, there is little known about how aspen stand area changes in response to overlapping fire. Our study area in northeastern California on the Lassen, Modoc and Plumas National Forests has …

The Feasibility Of Renewable Natural Gas In New Jersey, Anneliese Dyer, Amelia Christine Miller, Brianna Chandra, Juan Galindo Maza, Carley Tran, Justin Bates, Vicky Olivier, Amy Tuininga

PSEG Institute for Sustainability Studies Publications

With traditional natural gas being one of the top options for heating in the United States and the present threat of climate change, there is a demand for an alternative clean fuel source. A Renewable Natural Gas Implementation Decision-Making Conceptual Model was created to provide a framework for considering the feasibility of renewable natural gas (RNG) projects and applied to New Jersey, specifically investigating landfills and wastewater treatment plants (WWTPs). Data from the US EPA’s Landfill Methane Outreach Program and New Jersey’s Department of Environmental Protection Sewage Sludge databases were used to identify seven landfills and 22 WWTPs as possible …

Fire Alters Plant Microbiome Assembly Patterns: Integrating The Plant And Soil Microbial Response To Disturbance, Nicholas C. Dove, Dawn M. Klingeman, Alyssa A. Carrell, Melissa A. Cregger, Christopher W. Schadt

Aspen Bibliography

• It is increasingly evident that the plant microbiome is a strong determinant of plant health. While the ability to manipulate the microbiome in plants and ecosystems recovering from disturbance may be useful, our understanding of the plant microbiome in regenerating plant communities is currently limited.
• Using 16S ribosomal RNA (rRNA) gene and internal transcribed spacer (ITS) region amplicon sequencing, we characterized the leaf, stem, fine root, rhizome, and rhizosphere microbiome of < 1-yr-old aspen saplings and the associated bulk soil after a recent high-intensity prescribed fire across a burn severity gradient.
• Consistent with previous studies, we found that soil microbiomes are responsive to fire. We extend these findings by showing that certain plant tissue microbiomes also change in response to …

Future Dominance By Quaking Aspen Expected Following Short-Interval, Compounded Disturbance Interaction, Robert A. Andrus, Sarah J. Hart, Niko Tutland, Thomas T. Veblen

Aspen Bibliography

The spatial overlap of multiple ecological disturbances in close succession has the capacity to alter trajectories of ecosystem recovery. Widespread bark beetle outbreaks and wildfire have affected many forests in western North America in the past two decades in areas of important habitat for native ungulates. Bark beetle outbreaks prior to fire may deplete seed supply of the host species, and differences in fire‐related regeneration strategies among species may shift the species composition and structure of the initial forest trajectory. Subsequent browsing of postfire tree regeneration by large ungulates, such as elk (Cervus canadensis), may limit the capacity …

Effects Of Thinning On Dynamics And Drought Resistance Of Aspen-White Spruce Mixtures: Results From Two Study Sites In Saskatchewan, Philip G. Comeau

Aspen Bibliography

Drought stress associated with warm temperatures is causing increased mortality and reduced growth of trees in drier portions of the boreal forests of western Canada with both warming and drought expected to increase over the coming decades. While thinning is often shown to reduce drought stress, there is little information on its effects in stands comprised of mixtures of trembling aspen and white spruce that are common in the forests of this region. This study examined effects of pre-commercial thinning on aspen and spruce growth, response to drought stress, and stand dynamics for two study sites located in Saskatchewan, Canada. …

Identification And Functional Analysis Of Thadh1 And Thadh4 Genes Involved In Tolerance To Waterlogging Stress In Taxodium Hybrid ‘Zhongshanshan 406’, Lei Xuan, Jianfeng Hua, Fan Zhang, Zhiquan Wang, Xiaoxiao Pei, Ying Yang, Yunlong Yin, David Creech

Faculty Publications

The Taxodium hybrid ‘Zhongshanshan 406’ (T. hybrid ‘Zhongshanshan 406’) [Taxodium mucronatum Tenore × Taxodium distichum (L.). Rich] has an outstanding advantage in flooding tolerance and thus has been widely used in wetland afforestation in China. Alcohol dehydrogenase genes (ADHs) played key roles in ethanol metabolism to maintain energy supply for plants in low-oxygen conditions. Two ADH genes were isolated and characterized—ThADH1 and ThADH4 (GenBank ID: AWL83216 and AWL83217—basing on the transcriptome data of T. hybrid ‘Zhongshanshan 406’ grown under waterlogging stress. Then the functions of these two genes were investigated through transient expression and overexpression. The results showed that the …

Impact Of Maize Hybrid Selection On Water Productivity Under Deficit Irrigation In Semiarid Western Nebraska, Strahinja Stepanovic, Daran Rudnick, Greg R. Kruger

West Central Research and Extension Center, North Platte

The future economic and agricultural sustainability of semiarid western Nebraska will largely depend on more efficient utilization of the declining groundwater resources. The scope of this research was to evaluate the maize hybrid yield, water productivity (WP; i.e. grain yield produced per unit of water consumed), and irrigation water productivity (IWP; i.e. increase in grain yield per unit of irrigation water applied) across a range of semiarid climatic conditions (i.e. drought, normal, and wet) and irrigation treatments. Total of 13 maize hybrids were evaluated under full irrigation (FI), deficit irrigation (DI, receiving ~50% less irrigation water than FI), and dryland …

White River Aspen Management Project, Usda Forest Service

Aspen Bibliography

Comments Welcome

The White River National Forest (WRNF) welcomes your comments on its proposal to conduct vegetation management activities designed to sustain and expand aspen (Populus tremuloides) forests on National Forest System (NFS) lands. Your comments will help us further develop the proposed action, potential alternatives, and complete an environmental assessment. The assessment will be used to determine whether to prepare an environmental impact statement or a finding of no significant impact. Instructions for submitting comments are described on the last page. Additional project information is available here: https://www.fs.usda.gov/project/?project=59419

This Notice of Proposed Action (NOPA) is also requesting …

Vole Population Dynamics In Cover Crops Transitioning To Soybeans With Integrated Pest Management By Habitat Modification, Jena L. Nierman

Theses and Dissertations--Forestry and Natural Resources

The use of cover crops has been a wildly used method in rotational row crop production. Cover crops have minimized soil runoff and aided in maintaining nutrients in agricultural fields. Increased use of cover crops has seen a corresponding increase in the amount of damage done to soybeans by voles. Currently, there are no mitigation methods that successfully decrease vole populations in agricultural fields. The use of habitat manipulation as an integrated pest management solution has not been studied as a practical solution for vole population management. During 2019 and 2020, I tested the impacts of various cover crop termination …

An Evaluation Of Antiparasitics Used To Treat The Sea Louse, Caligus Rogercresseyi, In Chilean Salmonid Farming, Dayla Woller

Scripps Senior Theses

Sea lice pose a global threat to open-net salmonid farming. As Chile is the second largest Atlantic salmon producer, they have a vested interest in mitigating infestations and increasing production. However, this will not be possible without 1) increased research on the underlying mechanisms behind sea lice infestations that will inform 2) governmental regulation of salmon farming. This increase in research and governmental regulation will only be possible through transparency on pesticide practices and sea louse monitoring data from companies operating in Chile. Taking these steps would bring Chile closer to being the largest producer of Atlantic salmon and an …

Crop Salinity Tolerance Induction Using Novel Biostimulants (Saltibio), Elomofe Ikuyinminu

Theses

Salinity is one of the major abiotic stresses affecting crop production, especially in arid and semi-arid areas. Most of the vegetable crops are salt sensitive, growing inadequately in salinised soils due to the accumulation of toxic ions from prolonged, inadequate irrigation programs. A meaningful approach to counteract salinity stress and increase crop yield is the use of protein hydrolysate biostimulants (PHBs). The main objectives of this study were to generate legume-derived PHBs by enzymatic hydrolysis, evaluate their ability to induce salinity stress tolerance in plants, and understand their mode of action. A full compositional and structural analysis of the generated …

A Decision Tool To Identify Population Management Strategies For Common Ravens And Other Avian Predators, Andrea F. Currylow, Brenda J. Hanley, Kerry L. Holcomb, Timothy Shields, Stephen Boland, William I. Boarman, Mercy Vaughn

Human–Wildlife Interactions

Some avian species have developed the capacity to leverage resource subsidies associated with human manipulated landscapes to increase population densities in habitats with naturally low carrying capacities. Elevated corvid densities and new territory establishment have led to an unsustainable increase in depredation pressure on sympatric native wildlife prey populations as well as in crop damage. Yet, subsidized predator removal programs aimed at reducing densities are likely most effective longer-term when conducted in tandem with subsidy control, habitat management, and robust assessment monitoring programs. We developed decision support software that leverages stage structured Lefkovitch population matrices to compare and identify treatment …

Fungal Planet Description Sheets: 1112–1181, P. W. Crous, D. A. Cowan, G. Maggs-Kölling, N. Yilmaz, E. Larsson, C. Angelini, T. E. Brandrud, J. D. W. Dearnaley, B. Dima, F. Dovana, Et Al.

Aspen Bibliography

Novel species of fungi described in this study include those from various countries as follows: Australia, Austroboletus asper on soil, Cylindromonium alloxyli on leaves of Alloxylon pinnatum, Davidhawksworthia quintiniae on leaves of Quintinia sieberi, Exophiala prostantherae on leaves of Prostanthera sp., Lactifluus lactiglaucus on soil, Linteromyces quintiniae (incl. Linteromyces gen. nov.) on leaves of Quintinia sieberi, Lophotrichus medusoides from stem tissue of Citrus garrawayi, Mycena pulchra on soil, Neocalonectria tristaniopsidis (incl. Neocalonectria gen. nov.) and Xyladictyochaeta tristaniopsidis on leaves of Tristaniopsis collina, Parasarocladium tasmanniae on leaves of Tasmannia insipida, Phytophthora aquae-cooljarloo from pond water, Serendipita whamiae as …

Black Vulture Conflict And Management In The United States: Damage Trends, Management Overview, And Research Needs, Bryan M. Kluever, Morgan B. Pfeiffer, Scott C. Barras, Brett G. Dunlap, Lee A. Humberg

Human–Wildlife Interactions

Contrary to rapid declines of many vulture (Accipitridae, Cathartidea) species worldwide, black vulture (Coragyps atratus) populations are increasing and expanding their range in North America. Vultures exhibit complex behaviors and can adapt to any human-dominated landscape or land use. These traits, combined with population growth and range expansion, have contributed to increased human–vulture conflicts. Our goal was to summarize the current status and trends in human–black vulture conflicts (hereafter human–vulture conflicts), review available management strategies, identify knowledge gaps, and provide recommendations to enhance management and understanding of this species and the associated conflicts. We found human–vulture conflicts are …

Aspen Soils Retain More Dissolved Organic Carbon Than Conifer Soils In A Sorption Experiment, Antra Boča, Astrid R. Jacobson, Helga Van Miegroet

Aspen Bibliography

The effect tree species have on soil organic carbon (SOC) has been hotly debated but, so far, few clear patterns have emerged. One example of a differing tree species effect on SOC are aspen forests in North America, which have been found to have more stable SOC than adjacent conifer forest stands. An important source for the formation of stable organo-mineral complexes in soil is dissolved organic carbon (DOC). DOC concentrations in mineral soil are often higher under the thick O-horizons of conifer forests than under aspen forests, but this does not correspond to more stable mineral SOC. This suggests …

Endophyte-Infected Tall Fescue Affects Rumen Microbiota In Grazing Ewes At Gestation And Lactation, Jianmin Chai, Saleh Alrashedi, Ken Coffey, Joan Burke, Kristina M. Feye, Steven C. Ricke, Si Hong Park, J. Lannett Edwards, Jiangchao Zhao

Animal Science Faculty Publications and Presentations

Tall fescue (Schedonorus arundinaceus) is a cool-season perennial grass that is widely used as a forage for many livestock species including sheep. An endophyte (Neotyphodium coenophialum) in tall fescue produces ergot alkaloids that enhance plant survival but produce toxicosis in animals. The objective of this study was to investigate the rumen microbiota from gestation and lactation in ewes grazing tall fescue pastures with high (HA) or moderate (MA) levels of endophyte infection, and their relationship with serum parameters. Data were collected at the beginning of the study (d1), the week before initiation of lambing (d51), and at …

Distribution And Activity Patterns Of Large Carnivores And Their Implications For Human–Carnivore Conflict Management In Namibia, Summer Fink, Richard Chandler, Michael Chamberlain, Steven Castleberry, Shannon Glosenger-Thrasher

Human–Wildlife Interactions

Human–wildlife conflicts (HWCs) are increasing globally and contributing to the decline of wildlife species. In sub-Saharan African countries such as Namibia, most of the suitable land has been or is currently being converted to crop and livestock production to support income or subsistence agriculture. These changes in land use often incur increased levels of HWCs because of crop and livestock depredation by native species. To quantify livestock predation risks posed by carnivores in Namibia, we deployed 30 trail cameras on a 6,500-ha farm in the Khomas region of Namibia from May to July 2018. We developed occupancy models to make …

True Morels (Morchella Spp.) And Community Livelihood Improvement In Mankial Valley, District Swat, Khyber Pakhtunkhwa, Pakistan, Syed Fazal Baqi Kakakhel

Journal of Bioresource Management

True morels collected from wild provide an economic source for the rural community of Mankial valley (District Swat, Khyber Pukhtunkhawa, Pakistan). Sale of approximately 334 kg in dry weight of five species of true morels (Morchella conica, M. esculenta, M. deliciosa, M. rotunda and M. semilibera) fetch US$ 57133 (under US$ 2015-16 exchange rate) to Mankial community and generate a revenue of US$ 62935 in Mingora (regional market) and US$ 87011 in Islamabad (national capital) markets. Morchella conica (average annual dry weight harvested 156 kg) has a high market price value (US$ 2964-44616) in all the three markets. …

Simulated Fire Behavior And Fine-Scale Forest Structure Following Conifer Removal In Aspen-Conifer Forests In The Lake Tahoe Basin, Usa, Justin P. Ziegler, Chad M. Hoffman, Brandon M. Collins, Jonathan W. Long, Christa M. Dagley, William Mell

Aspen Bibliography

Quaking aspen is found in western forests of the United States and is currently at risk of loss due to conifer competition at within-stand scales. Wildfires in these forests are impactful owing to conifer infilling during prolonged fire suppression post-Euro-American settlement. Here, restoration cuttings seek to impact wildfire behavior and aspen growing conditions. In this study, we explored how actual and hypothetical cuttings with a range of conifer removal intensity altered surface fuel and overstory structure at stand and fine scales. We then simulated wildfires, examining fire behavior and effects on post-fire forest structures around aspen trees. We found that …

Drought- Conditioning Of Quaking Aspen (Populus Tremuloides Michx.) Seedlings During Nursery Production Modifies Seedling Anatomy And Physiology, Joshua L. Sloan, Owen T. Burney, Jeremiah R. Pinto

Aspen Bibliography

In the western US, quaking aspen (Populus tremuloides Michx.) regenerates primarily by root suckers after disturbances such as low to moderate severity fires. Planting aspen seedlings grown from seed may provide a mechanism to improve restoration success and genetic diversity on severely disturbed sites. However, few studies have examined the use of container-grown aspen seedlings for restoration purposes from both the outplanting and nursery production perspective. Thus, the purpose of this novel study was to examine how alterations in irrigation levels during nursery production across three seed sources would impact seedling performance attributes on harsh, dry outplanting sites. Irrigation …