Ecology and Evolutionary Biology Commons^™

Contrasting Effects Of Climate Warming On Hosts And Parasitoids: Insights From Rocky Mountain Aspen Leaf Miners And Their Parasitoids, Alisha A. Shah, Emily Hamant, Juan G. Rubalcaba, Beau Larkin, Andrew A. Forbes, H. Arthur Woods

Aspen Bibliography

Because temperature has pervasive effects on biological rates, climate warming may alter the outcomes of interactions between insect hosts and their parasitoids, which, for many host species, constitute the single largest source of mortality. Despite growing interest in parasitoid-host responses due to climate change, there are few empirical tests of thermal tolerance differences between non-model lepidopteran hosts and their parasitoids and almost none from mountain ecosystems where warming is occurring more rapidly. We examined the thermal ecology of a host–parasitoid interaction in the Rocky Mountains using the wild populations of the aspen leaf miner (Phyllocnistis populiella) and a …

Draft Genome Data Including Functional Annotation Of An Emerging Fungal Pathogen (Neodothiora Populina) Causing A Canker Disease Of Trembling Aspen In Interior Alaska, Ursel M. E. Schütte, Mace Wages, Aaron Buechlein, Jorda P. Kovash, Danielle C. Wrenn, Tereza Smrhova, Andrea Zubrova, Doug B. Rusch, Loretta M. Winton, Gerard C. Adams, Roger W. Ruess, Mary Beth Leigh, Devin M. Drown

Aspen Bibliography

Neodothiora populina is a black yeast-like fungus in the family Dothioraceae. It causes an aggressive canker disease of trembling aspen that results in widespread mortality of aspen across the boreal forest of Interior Alaska. Here we report a high-quality draft genome including functional annotation of this emerging fungal pathogen based on Oxford Nanopore Technologies long-read sequences. Our initial genome assembly totaled 23,960,169 bp and contained 18 contigs, and we identified 7,343 genes. This resource announcement provides new genomic data that are useful long term for improving our understanding of forest health in Alaska.

Bryce Canyon Aspen: Recent Trends, Future Actions, Paul C. Rogers

Aspen Bibliography

In cooperation with Bryce Canyon National Park, we undertook a survey of quaking aspen (Populus tremuloides Michx.) conditions throughout the Park with the intention of better understanding conditions and prescribing corrective measures where needed. There are clear disparities within the Park between sustainable aspen conditions and failing stands. Based on condition of mature trees, but most importantly regeneration and recruitment of juvenile stems, most aspen forests within Bryce Canyon are in poor condition. Aspen recruitment—generally sapling-sized trees that have survived browsing ungulates—is the most important metric of future stand resilience and here we found 83% of all aspen sample …

Changing Fire Regimes In The Great Basin Usa, Eva K. Strand, Kori Blankenship, Corey Gucker, Mark Brunson, Eugénie Montblanc

Aspen Bibliography

Wildfire is a natural disturbance in landscapes of the Western United States, but the effects and extents of fire are changing. Differences between historical and contemporary fire regimes can help identify reasons for observed changes in landscape composition. People living and working in the Great Basin, USA, are observing altered fire conditions, but spatial information about the degree and direction of change and departure from historical fire regimes is lacking. This study estimates how fire regimes have changed in the major Great Basin vegetation types over the past 60 years with comparisons to historical (pre-1900) fire regimes. We explore potential …

Occurrence Of Spotted Wing Drosophila (Drosophila Suzukii) In Wild Berries In Forested Areas Of Marquette And Keweenaw Counties, Upper Peninsula Of Michigan, Alexis M. Shatrau, Erika I. Hersch-Green

The Great Lakes Entomologist

Spotted-wing Drosophila (SWD, Drosophila suzukii Matsumura, Diptera: Drosophilidae) is an invasive fly that targets unripe soft-fruits causing premature ripening, dehiscence, and rotting. While the presence of SWD in agricultural systems is well-documented, much less is known about the host range of SWD in wild areas, especially in more northern latitudes where colder temperatures and short summers are thought to restrict their life-cycles and limit population growth. In 2019 and 2020, we collected wild berries from two counties in the Upper Peninsula of Michigan, with long, cold winters, to determine the prevalence, host range, and seasonal/temporal variation of SWD. We found …

Changes In Foliar Chemistry And Nutrient Resorption In Northern Hardwood Forests In Response To Long-Term Experimental Nitrogen And Phosphorus Addition, Jenna M. Zukswert, Timothy J. Fahey, Matthew A. Vadeboncoeur, Daniel S. Hong, Ruth D. Yanai

Faculty Publications

Northern hardwood forests have long been assumed to be primarily nitrogen limited, but may often be co-limited by multiple elements. Nutrient limitation can be inferred through responses of foliar and litter chemistry to nutrient addition over time. We compared community-level foliar and litter chemistry and resorption efficiency in a long-term, factorial nitrogen (N) and phosphorus (P) fertilization study across 10 forest stands at three sites in New Hampshire, where N and P were added annually. We measured N, P, calcium (Ca), magnesium (Mg), and potassium (K) in foliage from codominant trees and in fresh litter in 2008–2010 (pretreatment) and again …

Drought Resilience And Legacy Effects In Two Forest Tree Species On Loess Plateau Of China: Growth And Water-Use Efficiency Under Different Drought Conditions, Lu Han, J. Julio Camarero, Guodong Jia, Zhiqiang Zhang, Lixin Chen

Aspen Bibliography

As droughts become more frequent and severer, understanding tree resilience and its role in mediating drought legacy effects (LEs) is critical for predicting forest ecosystem responses to future droughts and informing forest management. Both Pinus tabuliformis and Populus davidiana are widely distributed in the Loess Plateau region of western China and play important roles in provision of ecosystem services. In this study we quantified the LEs and resilience, including resistance (Rt) and recovery (Rc), of radial growth (BAI, basal area increment) and intrinsic water use efficiency (iWUE) of the two species, determined the external and internal factors influencing Rt and …

Woody Plant Reinvasion Shortens The Lifespan Of Grassland Restoration Treatments, Dillon T. Fogarty, Michele Beadle, Craig R. Allen, Christine Bielski, Dirac Twidwell

Biology Student Work

An important question in restoration ecology is whether restored ecological regimes are more vulnerable to transitions back to a degraded state. In woody-invaded grasslands, high-intensity fire can collapse woody plant communities and induce a shift back to a grass-dominated regime. Yet, legacies from woody-dominated regimes often persist and it remains unclear whether restored regimes are at heightened vulnerability to reinvasion. In this study, we utilize a 17-year history of fire-based restoration in Nebraska's Loess Canyons Experimental Landscape to determine whether restored grassland regimes experience faster rates of Juniperus virginiana (eastern redcedar) reinvasion compared to the initial invasion process in adjacent …

Timber Harvesting Was The Most Important Factor Driving Changes In Vegetation Composition, As Compared To Climate And Fire Regime Shifts, In The Mixedwood Temperate Forests Of Temiscamingue Since Ad 1830, Daniela Robles, Yan Boulanger, Jesus Pascual, Victor Danneyrolles, Yves Bergeron, Igor Drobyshev

Aspen Bibliography

Context The vegetation composition of northeastern North American forests has significantly changed since pre-settlement times, with a marked reduction in conifer-dominated stands, taxonomic and functional diversity. These changes have been attributed to fire regime shifts, logging, and climate change.

Methods In this study, we disentangled the individual effects of these drivers on the forest composition in southwestern Quebec from 1830 to 2000 by conducting retrospective modelling using the LANDIS-II forest landscape model. The model was run based on pre-settlement forest composition and fire history reconstructions, historical timber harvest records, and climate reanalysis data. We compared counterfactual scenarios excluding individual factors …

Evaluating Elk Distribution And Conflict Under Proposed Management Alternatives At The National Elk Refuge In Jackson, Wyoming, Gavin G. Cotterill, Paul C. Cross, Eric K. Cole, Jonathan D. Cook, Margaret C. Mceachran, Tabitha A. Graves

Aspen Bibliography

We evaluated measurable attributes describing the current and future distribution of Cervus elaphus canadensis (elk) across a region surrounding Jackson, Wyoming, for five feedground management alternatives proposed by the U.S. Fish and Wildlife Service as a revision to 2007 "Bison and Elk Management Plan" of the National Elk Refuge. A resource selection function evaluated measurable attributes of interest to managers, including elk use of private property and sensitive habitat types at monthly timesteps and varying winter conditions. The study area boundaries were created through an expert elicitation process and consist of the Jackson Elk Herd Unit, Grand Teton National Park, …

Increased Positive Tree Species Mixture Effects On The Abundance And Richness Of Collembola With Stand Development In Canadian Boreal Forests, Yakun Zhang, Sai Peng, Zilong Ma, Chen Chen, Bilei Gao, Xinli Chen, Han Y.H. Chen

Aspen Bibliography

It is well established that species mixtures could enhance ecosystem functioning in diverse ecosystem types, with these benefits increasing over time. However, the impact of tree mixtures on Collembola communities following stand development in natural forests remains unclear, despite the critical roles Collembola plays in litter decomposition and nutrient cycling. We investigated the effects of tree species mixtures on Collembola abundance, diversity, and community structure by sampling pure and mixed jack pine (Pinus banksiana Lamb.) and trembling aspen (Populus tremuloides Michx.) of 15-year-old and 41-year-old stands in natural boreal forest. In total, 6,620 individuals of Collembola were identified …

Feasibility Of Producing Non-Structural Wood Products Using Trembling Aspen Lumber, Mengyuan Zhang

Aspen Bibliography

Trembling aspen (Populus tremuloides) is abundant in Canada but underutilized in non-structural solid wood products.This study was aimed at evaluating the feasibility of using aspen lumber to produce flooring, moulding, and siding. The shrinkage, surface roughness, and wettability of aspen wood were tested. The surface hardness, screw withdrawal resistance, colour change, and dimensional stability of there products fabricated were examined. The wood yield of each product was analyzed. It was found that aspen showed superior machinability and wettability to silver maple and yellow poplar. Aspen flooring had a Brinell hardness of 13.47 MPa, 60% lower than silver maple. …

Assessing Understory Along The Elk River (Hikshari') In Headwaters Forest Reserve, Humboldt County, California, Julie R. Meyers, Aliyah M. Ingram, Caleb N. Larkin, Joshua L. Carpenter

Environmental Science & Management Senior Capstones

Northern California’s extensive logging history and lack of forest management has altered old-growth coast redwood (Sequoia sempervirens) forests, leaving dense, homogenous second and third-growth forest stands. This has led to the use of modern restoration techniques such as variable density thinning (VDT) which aims to rehabilitate old-growth forest conditions by improving stand heterogeneity and light availability for understory species. Our study was done in Headwaters Forest Reserve (HFR) along the Elk River (Hikshari’) Trail in Humboldt County, California. Initially, the project was supervised by the Bureau of Land Management (BLM) Arcata Field Office. However, the 2025 U.S. government …

Critical Environmental Communication Framework, Shumaila J. Bhatti, Srivi Ramasubramanian, Andrea Feldpausch-Parker, Bruno Takahashi, Silje Kristiansen

Media Studies - All Scholarship

This study develops a Critical Environmental Communication (CEC) framework to assess the landscape of Environmental Communication research and to what extent and in which ways critical and justice-oriented perspectives are included. The CEC framework consists of four interconnected themes: (a) Marginalized Ecocultural Identities, (b) Context and Scale, (c) Power and Agency, and (d) Justice, Equity, Diversity, Access, and Inclusion (JEDAI). Using this framework in a bibliometric analysis examining 1,297 Environmental Communication publications, we assess the occurrence of these themes in the scholarship. Our analysis found that Marginalized Ecocultural Identities, and Context and Scale were most frequently occurring, while Power and …

Potential Of Using Trembling Aspen To Make Structural Engineered Wood Products, Dawei Wang

Aspen Bibliography

Trembling aspen (Populus tremuloides) is abundant in Canada but is widely considered an underutilized species. This study was aimed at evaluating the potential of using aspen lumber to produce cross-laminated timber (CLT), glued-laminated timber (glulam), and wood I-joists. The key mechanical properties of these engineered wood products, which were fabricated using a modified grading criterion, were examined. It was found that 1) The mean effective bending stiffness and characteristic bending moment resistance of 5-layer CLT specimens in the major-strength direction were 5,069x10⁹ N·mm²/m and 97.65x10⁶ N·mm/m; 2) The mean apparent MOE and characteristic modulus …

Dam It All: A Multi-Scalar Investigation Into The Ecological Role And Function Of Beaver Dams, Kenneth Larsen

Dissertations, Master's Theses and Master's Reports

The central theme of this dissertation is ecological scaling, which examines how small, localized features, such as beaver ponds, contribute to large-scale watershed processes and how different modeling approaches at various scales reveal distinct insights. Through a combination of probabilistic modeling and high-resolution empirical research, this work demonstrates that small ponded systems, particularly those created by beavers (Castor canadensis), serve as critical biogeochemical control points, whose contributions to sediment and nutrient dynamics have been historically underestimated.

In Chapter 1, I contextualize this research within the broader fields of freshwater ecology, watershed modeling, and ecological restoration. I introduce the …

Age Class Is Not Related To Size Or Composition Of Home Ranges Among Suburban White-Tailed Deer During Parturition, Nathan D. Pyburn

Journal of Earth and Life Science

How white-tailed deer use the landscape in an urban environment can help us understand the effects of urbanization on deer populations. White-tailed deer form observable matriarchal hierarchies in studied populations. This study examines the matriarchal structure, home range size, and home range composition of 25 collared white-tailed deer within the city limits of Bemidji, MN. The results found no significant difference between age class and home range size or composition. However, movement metrics from yearling and mature age classes were more similar than the juvenile age class females. I propose this is because social acceptance between mature females was higher …

Tree Crown Economics Of Broadleaf Deciduous Forests, Yiting Fan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tree crown architecture, a critical determinant of forest ecosystem processes such as photosynthesis, evapotranspiration, and spectral reflectance, is shaped by adaptive trade-offs in resource use and environmental responses. However, significant gaps remain in our understanding of how these traits vary across species, environmental gradients, and temporal scales. This dissertation addresses these gaps by employing remote sensing data across three interconnected studies. Together, these studies advance tree crown economic theory, highlighting how crown traits mediate trade-offs between light capture and water-use efficiency and how these traits influence forest responses to global change. Collectively, this dissertation offer insights for improving models that …

Balancing Timber Harvest And Biodiversity: Impacts Of Selective Logging On Wildlife In The Chiquibul Forest Reserve, Belize, Kilynn Groen

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Selective logging is often promoted as a sustainable forestry practice that maintains biodiversity and ecosystem function, yet its ecological consequences remain under examined, particularly in tropical forests. This study investigates how selective logging affects wildlife communities in the Chiquibul Forest Reserve, Belize. Using remote camera trap data from 22 sites (9 unlogged forest sites and 13 logged (stump) sites), we assessed species richness, trophic structure, and environmental predictors of wildlife abundance. While overall wildlife captures and species richness did not differ significantly between forest and stump habitats, principal component analysis revealed strong community-level separation, with stump habitats supporting distinct species …

Sugar Maple (Acer Saccharum Marsh.) Tree-Ring Growth And Carbon Stable Isotope Responses To Nitrogen And Climate, Libbie Ring

Dissertations, Master's Theses and Master's Reports

This dendrochronological and stable carbon isotope study used tree rings from sugar maple (Acer Saccharum Marsh.) collected at long-term nitrogen (N) amended sites throughout Michigan to understand N amendment and deposition, climate, and growth relationships. Climate responses varied by site, however, we found importance in grouping sites by “productivity” which is related to inherent N and soil nutrients. Our results did not detect an overall effect of N amendments on growth during the treatment period. However, data shows N amendments benefiting larger diameter trees, while smaller diameter trees responded more positively without amendments, especially on more productive sites. Results …

Acer Rubrum: Descending Towards Forest Dominance, Elyssa L. Pearson, Christopher M. Gough

UROP Posters

Acer rubrum, more commonly known as the red maple, is a hardwood, late successional species of tree commonly planted for its deciduous nature and vibrant coloring of its leaves in the beginning of autumn (Abrams, 1998). The species is very tolerant of varying light and soil moisture levels and often dominates sub and mid-canopy levels of hardwood forests (Missouri Botanical Gardens). It was hypothesized that as the I moved from an upland location to a lowland location near a wetland that the A. rubrum trees would be more productive and have a greater above ground biomass. This was not …

The Role Of Floodplain Complexity In Wood Turtle Habitat Use, Laura S. Deming

Antioch University Dissertations & Theses

Wood turtles occupy cold, low-gradient riverine habitat throughout the northeastern United State and southeastern Canada. Stream alterations, such as dams, channel straightening, and floodplain development have diminished the natural hydrologic and sedimentation regimes that result in complex channel and floodplain geomorphology. Studies throughout the species’ range have quantified many aspects of their habitat, but none have quantified components of geomorphology of wood turtle sites. The goal of this study was to explore the role of stream channel and floodplain geomorphology in wood turtle habitat use, with specific objectives to (1) quantify components of stream channel and floodplain geomorphic complexity, (2) …

Spatial Analysis Of American Chestnut (Castanea Dentata) Distribution And Ecology In Kentucky’S Federal Lands, Jacob Raymond Pease

Murray State Theses and Dissertations

Anthropogenic factors have been the cause of the decline of tree species across the globe. From unsustainable logging and development to disease and improper management, threats to forests have taken their toll. The American chestnut (Castanea dentata) was once an integral basal tree species in Appalachian forests, but chestnut blight drove the species to functional extinction by the mid-1900s. The recent creation of genetically modified chestnuts gives hope for future restoration of the species throughout its historical range. Despite blight resistance, effective restoration will require optimal site selection for finding and planting chestnuts, which will maximize limited resources. …

Wildlife Distribution Mapping And Analysis In Gorongosa National Park, Mozambique, Using Site And Satellite Imagery Data, Pinho Joaquim Munhequeira Mr

Murray State Theses and Dissertations

One of Mozambique's most important conservation sites, Gorongosa National Park has seen critical ecological changes over the past several decades resulting from climate variability, habitat loss, and political instability. This research integrates Geographic Information Systems (GIS) and remote sensing to examine the relationship between vegetation dynamics and wildlife population, and distribution. The main goals of this study are to evaluate the spatial distribution of particular wildlife species: buffalo (Syncerus caffer), elephant (Loxodonta africana), hippopotamus (Hippopotamus amphibius), and zebra (Equus quagga), and determine the impact of vegetation density and land cover on their …

Economic Analysis And Profitability Of Honey Production And Marketing In Cross River State, Nigeria, Joseph A. Ugbe, Tee T.N., Ancha P.U

Journal of Bioresource Management

The significance of honey in the socio-economic livelihoods of rural and semi-urban populations is paramount, as it tackles issues such as unemployment, income, and ecosystem preservation. The decrease in the timber industry has caused numerous individuals who rely on forests for their income to be without jobs, making it difficult to find other ways to make a living. This study examines the economic analysis and profitability of honey production and marketing in Cross River State, Nigeria, over 5 years (2017-2021) for sustainable forest management. Six hundred and eighty-four (684) respondents were selected from three ecological zones in the state using …

Function Over Form: The Benefits Of Aspen As Surrogate Brood-Rearing Habitat For Greater Sage-Grouse, Michel T. Kohl, Charles P. Sandford, Paul C. Rogers, Renee Chi, Terry A. Messmer, David K. Dahlgren

Aspen Bibliography

Species of conservation concern are often habitat specialists, posing significant risk to those species when specific plant communities are threatened. As a result, practitioners habitually focus conservation efforts on these communities while ignoring ecological mechanisms that explain the wildlife–plant relationships. In doing so, practitioners may overlook alternative vegetation communities that could maintain wildlife populations under alternative conditions (e.g., climate change). Here, we term these areas surrogate habitat, defined as vegetation communities or resource sites that provide similar critical resources as conventional sites, and assess their potential for conservation using a case study of greater sage-grouse (Centrocercus urophasianus) on …

Tree Rings Reveal Mixtures Of Aspen And Spruce Exhibit Greater Drought Resilience In A Planted Field Experiment, Jéssica Chaves Cardoso, Linhao Wu, Marcel Schneider, Charles A. Nock

Aspen Bibliography

Boreal forests provide a wealth of ecosystem services, many of which are linked to forest productivity. Climate change is expected to increase the frequency, duration, and severity of drought, and undermine the productivity of western boreal forests. Favouring species mixtures has emerged as a potential strategy to increase forest resilience to drought. To test the hypothesis that mixtures of trembling aspen and white spruce were more productive than pure stands because they were more resistant and resilient to drought, we analyzed community and species responses to drought utilizing measurements of annual growth obtained from stem disc samples from a planted …

Comparing Multivalent Cross-Linked Sodium Alginate/ Montmorillonite Beads Containing Curcumin Or Cayenne Pepper As Drug Carriers And Their Antimicrobial Resistance, Shionainn Traynor, Shubham Sharma

SURE Journal: Science Undergraduate Research Experience Journal

The aim of the following work was to investigate and compare curcumin and cayenne pepper in microbeads composed of sodium alginate (SA) crosslinked with montmorillonite (MMT) to act as drug carriers and their antimicrobial resistance. The microbeads were prepared through ion-exchange in multivalent solutions of CaCl₂, MgCl₂ and AlCl₃. The microbeads were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX) and the time required for intercalation of curcumin and cayenne pepper with MMT. Simulated intestinal fluid (pH 7.3) and gastric fluid (pH 1.2) at 37°C were used for comparison in swelling studies. …

Editorial - Sure Journal Vol 6, Anne M. Friel, Eva Campion, Sinead Loughran

SURE Journal: Science Undergraduate Research Experience Journal

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Assessing Spatial Distribution And Quantification Of Native Trees In Saskatchewan's Prairie Landscape Using Remote Sensing Techniques, Elham Shafeian, Bryan J. Mood, Kenneth W. Belcher, Colin P. Laroque

Aspen Bibliography

The importance of trees in non-forest landscapes has been the focus of only a few studies. However, these trees provide many important ecosystem services. In this study, we mapped and quantified these trees using Sentinel-2 (S2) and very high-resolution (VHR) Google satellite imagery without any field campaigns. We performed a Random Forest (RF) classification to map the spatial distribution of native trees in different scenarios. The optimal model showed an overall accuracy and kappa of 0.99 and 0.98, respectively. We mapped 40,500 km² of tree cover, including native tree cover (approximately 29,565 km²≈10.5%), excluding plantations, regional and …