Ecology and Evolutionary Biology Commons^™

Quantitative Silviculture Of Northern Conifers, David G. Ray

Electronic Theses and Dissertations

Quantitative tools used to guide the management of important northern conifer species require updating and refinement to address changes in the contemporary resource and evolving objectives of ownership. This work builds on an extensive body of knowledge about stand density management and innovates some new approaches. In sum, the three chapters presented herein: 1) seek to strengthen and more fully articulate arguments for adopting relative density as a primary metric of stand density assessment, 2) quantify minimum stand densities to achieve full site occupancy and argue for more parity with treatment of maximum stand density, and 3) present an empirically …

Wetlands In Our Backyard: A Review Of Wetland Types In Virginia State Parks, Kirsten Bauer, Benjamin K. Campbell

Virginia Journal of Science

Wetlands constitute a significant component of Virginia’s natural resources and heritage. Though historically they have been discounted—and often denigrated—the exceptional value of wetlands is currently growing in recognition and appreciation. In addition to the value provided by extracted resources and ecological regulation, wetlands also offer people the opportunity to enrich themselves through cultural, educational, and recreational pursuits. The state parks of Virginia provide access to a variety of ecosystems, including a wide array of wetland types. In this review, we document the diversity of wetlands in Virginia State Parks through a typology that groups wetland systems into the three principal …

Observational Study Of Woolly Monkey Behavior And Vocalizations: Behavioral Time Allotment And Vocalization Habits Of A Small Population Of Poeppig’S Woolly Monkey (Lagothrix Lagotricha Poeppigii) In The Ecuadorian Amazon, Marina Smith-Hanke

Independent Study Project (ISP) Collection

Poeppig’s woolly monkey (Lagothrix lagotricha poeppigii), a species of primate native to the Amazonian regions of western Brazil, eastern Ecuador, and northeastern Peru, is classified as endangered by the IUCN. These large, frugivorous primates are threatened by habitat loss and climate change as a result of human interference. Deforestation, hunting, petroleum mining, and illegal trafficking are all huge threats to this species. As a result of these pressures, their populations have decreased by at least 30% over the past three generations. However, as keystone seed dispersers, they are essential for Amazonian ecosystem health; without their seed dispersal services, a loss …

Afforestation And Biodiversity: Bryophyte Richness Changes Between Icelandic Forest Types, Kian Mcdonough

Independent Study Project (ISP) Collection

Forest-dwelling bryophytes (mosses, liverworts, hornworts) greatly contribute to biodiversity and ecosystem function but are largely under-studied in comparison to vascular plants. With Iceland’s large-scale afforestation efforts there is a need to understand how different afforestation species are affecting biodiversity, including bryophyte diversity. This study looked at differences in ground-floor bryophyte richness across Sitka spruce, lodgepole pine, and downy birch forests and found that bryophyte richness was highest in the Sitka spruce forests and lowest in downy birch forests. While this suggests a negative correlation between bryophyte richness and light availability, since the conifer species have the densest copy cover, other …

The Specific Richness Of Forest Cockroach Communities In The Region Of Aflou (Laghouat; Algeria), Fatiha Masna, Siham Bounadji, Saliha Benhissen, Zakaria Hedjouli, Abdelmadjid Yagoub Asloum, Sarra Habbachi, Waffa Habbachi

Journal of Bioresource Management

Forest cockroaches are among the insects that play an important and effective role in forest formations, they are insects with incomplete metamorphosis belonging to the order of Blattodea. This work is a contribution to the knowledge of Blattoptera species existing in the forest environments of Aflou’s region (Laghouat; Algeria).The inventory was carried out monthly in the El-Khnegue Forest (Aflou) from February 2019 to May 2019. It revealed the presence of six species of forest Cockroaches, which belongs to 4 genera of the Blattelidae family. After identification, it was demonstrated that, these species were: Dziriblatta nigriventris (Chopard, 1936), Dziriblatta stenoptera (Chopard, …

Just Cut It Out, Jack Barbosa, Ashley Curcio, Emiliana Martinez-Nobrega, Matthew Robledo

Student Work

Why should we care about trees? Social, Economic, and Environmental benefits.

Plant Community Responses To Interactive Anthropogenic Disturbances Along A Natural-Wildland-Urban Gradient And Undergraduate Students’ Attitudes Toward Disturbances, Mali M. Hubert

Doctoral Dissertations

Anthropogenic disturbances are defined as any change caused by human activity that alters biodiversity. Wildfire and urbanization disturbances are among the most influential on the landscape because of their individual and interactive properties. Areas deemed wildland-urban interfaces (WUI; area where environment intermingles with human-built structures) are increasing near protected lands because of human population growth and movement, which often facilitates fire ignitions by humans. Houses that are adjacent to or overlap with wildland vegetation can complicate protection of urban development and wildlands from fires. The expansion of the WUI due to population growth will exacerbate fire risk, which can ultimately …

Assessing The Long-Term Effects Of Natural Disturbance-Based Silvicultural On The Avian Assemblage At The Acadian Forest Ecosystem Research Program, Carl Pohlman

Electronic Theses and Dissertations

Active forest management alters the resources available to forest-obligate species. Large-scale intensive management practices where timber production is the primary objective can lead to notable ecological changes in forest ecosystems. A key concept of ecological forestry is to design forest management activities to emulate natural disturbance regimes as a way to maintain the ecological integrity of forests. The Acadian Forest Ecosystem Research Program (AFERP) was undertaken as an experimental demonstration of management reflective of the region’s disturbance regime, which typically produces small canopy gaps. AFERP includes nine research areas assigned to three silvicultural treatments: unharvested control, small gap (expanding-group selection …

Relating Occupancy Patterns To Multi-Life-History Scales For Pond-Breeding Anurans In Eastern Virginia, Patrick A. Hardner

Undergraduate Honors Theses

Amphibians are experiencing population declines worldwide due to a multitude of factors, including habitat loss. Therefore, assessments of breeding habitat occupancy are important to determine which environmental characteristics are crucial for conservation of amphibians. While most research assesses habitat conditions at the breeding site (i.e., pond or wetland), for many species this misrepresents annual habitat use as many migrate to terrestrial habitats once breeding is completed. To provide a comprehensive assessment of annual habitat use, we evaluated how anuran (i.e., frog and toad) breeding site occupancy related to three life-history scales: breeding, migration and dispersal. Basically, the three scales define …

The Role Of Leaf Decomposition In Macroinvertebrate Colonization, Bethany Mabel Lian Schorr, Kevin Geedey

Independent Research Projects

Decomposition plays an important ecological role in carbon and nutrient cycling that supply food and energy resources to food webs. This study investigates the potential role that leaf decomposition of different leaf species may play in macroinvertebrate assemblages in upper Midwest streams. We hypothesized that the different decomposition rates experienced with different leaf species and in different streams would have an effect on invertebrate colonization due to the variance in nutrient availability. Due to altered fire regimes and other influences, forests are experiencing declines in fire-adapted, heliophytic species such as oaks and compositional shifts toward shade-tolerant, mesophytic species such as …

Potential Effects Of Amynthas Agrestis Invasion On Woody Understory Flora In The Cvnp, Christian Mammana

Williams Honors College, Honors Research Projects

Ohio forests are threatened by the invasive ecosystem engineer A. agrestis. A. agrestis invasion typically co-occurs with the ecosystem engineer, Odocoileus virginianus, where their impacts may synergize. To determine the direct effects of A. agrestis invasion, fenced plots across the Cuyahoga Valley National Park that excluded deer were utilized. The species richness, Shannon diversity and evenness of woody understory flora was measured in each plot. Mustard extraction was used to determine earthworm abundance. Correlations between abundance and measured variables were used to highlight potential invasion effects. Abundance and species richness was found to have a significant, positive correlation (p = …

Advancing Forest Structure-Function Relationships: Linking Above- And Belowground Structure To Soil Respiration, Laura J. Hickey

Theses and Dissertations

Variation in the soil-to-atmosphere C flux, or soil respiration (Rs), is influenced by a suite of biotic and abiotic factors, including soil temperature, soil moisture, and root biomass. However, whether canopy structure is tied to soil respiration through its simultaneous influence over these drivers is not known. We assessed relationships between measures of above- and belowground vegetation density and complexity, and evaluated whether Rs is linked to remotely sensed canopy structure through pathways mediated by established biotic and abiotic mechanisms. Our results revealed that, at stand-scale, canopy rugosity–a measure of complexity–and vegetation area index were coupled to soil respiration through …

A Comparison Of Wildfire Adaptive Traits In Juvenile Conifers Of The Northern Rockies, Andie Sonnen

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Wildfire is an importance disturbance that continues to shape the ecosystems of the northern Rockies through varying patterns of frequency and intensity. Due to historical fire suppression and the hotter and drier conditions brought upon by anthropogenic climate change, wildfire frequency and intensity is increasing. These increases will alter vegetation structure and composition, but the degree to which is unknown.

Individual plant traits can offer insight into how these vegetation communities will shift, especially the particular traits that reduce fire-related mortality. To survive wildfires, juvenile northern conifers employ two strategies: increasing their bark thickness and increasing their crown height. To …

The Impacts Of Maple Syrup Production On The Herbaceous Layer In Appalachian Hardwood Forests, Logan Scott Ferguson

Graduate Theses, Dissertations, and Problem Reports

Vegetation data were collected from eight maple syrup farms (sugarbushes) and eight undeveloped maple-dominated sites to examine potential differences in understory plant communities due to disturbance effects. Understory plants were identified to the species level and percent cover of aboveground leaf-area for each species was estimated within 600 total quadrats. Overstory data and environmental data were collected to help determine if they had any effect on herbaceous-layer plant communities. Species richness, Shannon diversity, and Pielou’s evenness were calculated, with the analysis showing no significant differences between the site types. The absolute cover of plant functional groups was also compared between …

Frayed Connections: How Long-Term Nitrogen Additions Disrupt Plant-Soil Interactions And The Carbon Cycle Of A Temperate Forest, Brooke A. Eastman

Graduate Theses, Dissertations, and Problem Reports

Forests are expected to mitigate some of the negative effects of climate change by sequestering anthropogenic carbon (C) from the atmosphere, but the degree to which they drawn down C will depend on the availability of key nutrients, such as nitrogen (N). There is a fair amount of uncertainty in the future of the forest C sink, mostly owing to the fate of soil organic matter (SOM) and soil heterotrophic respiration to future conditions. In N limited systems, plants allocate a significant amount of their photosynthate belowground for the acquisition of nutrients, but under conditions of chronic N deposition, plants …

Coupled Structure-Function Responses To Disturbance: High Structural Complexity Resistance Supports Primary Production Resistance, Kerstin M. Niedermaier

Theses and Dissertations

The capacity of forests to resist structural change and retain material legacies–the biotic and abiotic resources that persist through disturbance–is crucial to sustaining ecosystem functioning after disturbance. However, the role of forest structure as both a material legacy and feature supporting carbon (C) cycling stability following disturbance has not been widely investigated. We used a large-scale disturbance manipulation to ask whether LiDAR-derived canopy structures as material legacies drive 3-year responses of NPP to a range of disturbance severity levels. As part of the Forest Resilience Threshold Experiment (FoRTE) in northern Michigan, USA we simulated phloem-disrupting disturbances at a range of …

Changes In Plant Community Composition, Structure, And Function In Response To Permafrost Thaw, Katherine Standen

Theses and Dissertations (Comprehensive)

Air temperature is increasing at three or more times the global average in high latitudes, causing widespread permafrost thaw across the boreal biome. Since the boreal biome stores 30-40% of global terrestrial carbon (C), of which about 30-45% is found in permafrost soils, this temperature increase could cause a large efflux of C to the atmosphere. Climate warming and permafrost thaw are also expected to alter plant community composition and productivity and, given the link between plant functional traits and ecosystem C fluxes, may alter overall ecosystem function. Across the boreal biome of western Canada, we know surprisingly little about …

Targeted Browsing With Goats For Eastern Redcedar (Juniperus Virginiana L.) Control, Alanna M. Hartsfield

Electronic Theses and Dissertations

As eastern redcedar (ERC) (Juniperus virginiana L.) grassland encroachment progresses, all potential control methods should be explored in the interest of Great Plains grassland health and longevity. Targeted browsing with goats has been proven as an effective control method on some juniper species; however, little is known about its ability to control ERC. These studies intend to mend knowledge gaps of how targeted browsing with goats control ERC by causing tree death without chemicals or machinery. The first study is two 3x3 Latin squares comparing protein-supplemented diets. The second study is a randomized complete block design of five 0.224 ha …