Ecology and Evolutionary Biology Commons^™

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …

Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity of …

Spatial Upscaling Of Forest Response To Drought, Wei Fang, Peipei Xu, Tao Zhao, Xiang Zhao, Hui Luo, George Hendrey, Chuixiang Yi

Publications and Research

We have integrated the observational capability of satellite remote sensing with plot-scale tree ring data to up-scale the evaluation of forest responses to drought. Satellite data, such as Normalized Difference Vegetation Index (NDVI), can provide a spatially continuous measure with limited temporal coverage, while tree Ring Width Index (RWI) provides accurate assessment with much longer time series local scales. Here, we explored the relationship between RWI and NDVI of three dominant species in the Southwestern United States (SWUS), and predicted RWI spatial distribution from 2001 to 2017 based on MODIS 1-km resolution NDVI data with stringent quality control. We detected …

A Delicate Balance: The Effects Of Habitat Type On Frog Communities: A Three-Pronged Study Examining The Effects Of Differing Habitat Characteristics On Anuran Diversity At El Centro De Investigación Sumak Kawsay In Situ, Ecuador, Zane Libke

Independent Study Project (ISP) Collection

We conducted 60 hours of visual encounter surveys and 3 hours of calling surveys on 6 different habitat types near Sumak Kawsay in situ Reserva (SKIS) near Mera, Pastaza, Ecuador. We defined habitat types defined by two variables: type of forest and proximity to water. The aim of the study was to determine what effect each variable has on anuran community composition. We compared the effectiveness of the two survey methods as well. High anuran community dissimilarity was found between each habitat type surveyed, indicating that both forest type and proximity to water are important factors that shape species richness …

Diversity And Abundance Of Soil Microbes Differ Along A Forest-Pasture Transect, Hannah Suli, Ashley Schumann, Cleo Bickley, Jasmine Rodriguez

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.

Diffuse Light And Wetting Differentially Affect Tropical Tree Leaf Photosynthesis, Z. Carter Berry, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

‐Most ecosystems experience frequent cloud cover resulting in light that is predominantly diffuse rather than direct. Moreover, these cloudy conditions are often accompanied by rain that results in wet leaf surfaces. Despite this, our understanding of photosynthesis is built upon measurements made on dry leaves experiencing direct light.

‐Using a modified gas exchange setup, we measured the effects of diffuse light and leaf wetting on photosynthesis in canopy species from a tropical montane cloud forest.

‐We demonstrate significant variation in species‐level response to light quality independent of light intensity. Some species demonstrated 100% higher rates of photosynthesis in diffuse light …

Warming Up: Climate Change Related Shifts Of Mycorrhizal Fungal Communities In High Latitude Ecosystems, Megan Rae Devan

Biology ETDs

This dissertation examines how climate change affects mycorrhizal fungal communities in boreal and arctic ecosystems. In chapter one, I revealed that increases in fire severity and related increases in deciduous tree dominance result in greater Ascomycota relative abundance (RA) and subsequent declines in Basidiomycota RA. In chapter two I analyzed the effects of post-fire mycorrhizal fungal communites on host growth. There were trends at the fungal genus level that were largely reflected at the guild level across all hosts; however, there were some fungal genera that had the opposite effect on different host species. In chapter three, I found host …

Herpetological Assemblages In Tropical Dry Forests Of The Azuero Peninsula, Panama: An Evaluation Of Reforestation, Tyler Kovacs

Masters Theses, 2010-2019

Tropical dry forests are considered one of the most endangered tropical ecosystems making reforestation increasingly necessary to restore Panama’s unique ecoregion. The isolated dry ecoregion surrounding the Bay of Parita in Panama has a long history of deforestation and cattle grazing. Successful reforestation of this land is important to restore ecosystem health and biodiversity. In Panama, reforestation ranges from monocultures of exotic teak (Tectona grandis) to passive regeneration. Faunal recovery within these reforestation systems may vary due to different habitat characteristics. In this study, amphibian and reptile communities were compared in two types of reforestation systems and protected riparian forests …

Amphibian And Reptile Community Responses To Forest And Riparian Disturbance, Jacquelyn Christine Guzy

Graduate Theses and Dissertations

Riparian zones are transitional, semi-terrestrial areas regularly influenced by freshwater. These areas serve as dispersal corridors for many animal and plant species and ultimately function as important reservoirs of biodiversity in altered landscapes. While much of the riparian habitat in the United States has been affected by anthropogenic activities, management actions may mitigate potentially negative influences of these activities. For example, Streamside Management Zones (i.e., riparian buffers; SMZs) are commonly implemented within managed forests to protect water quality, but may also provide habitat for riparian-associated wildlife. Yet, little research has rigorously addressed the value of SMZs for wildlife, particularly cryptic …

Cool And Warm Season Climate Signals In Tree Rings From North America, Max Carl Arne Torbenson

Graduate Theses and Dissertations

Earlywood (EW) and latewood (LW) ring-width chronologies have become an increasingly important proxy in paleoclimate reconstructions. These subannual variables can provide estimates of past hydroclimate variability for seasonal windows that total ring-widths cannot resolve. The strength of the relationship between EW and LW series may influence what type of paleoclimate information is embedded within the tree-ring series. High correlations (> 0.70) between EW and LW are recorded for much of the continent but the magnitude of correlation varies greatly across space and species boundaries. Using four LW chronologies from shortleaf pine, the North American conifer species displaying the lowest EW-LW …

Trends In Nectar Production And Concentration Of Hummingbird-Pollinated Flowers: An Investigation Of Three Flowers Of The Ecuadorian Cloud Forest: Palicourea Demissa, Mezobromelia Capituligera, And Kohleria Affinis, Grace Palmer

Independent Study Project (ISP) Collection

Nectar concentration and sugar production both impact and are impacted by pollinator activity through a complex system of coevolution. Additionally, a variety of morphological and environmental factors influence the nectar properties of animal-pollinated flowering plants. Nectar concentration and nectar production rate (NPR) of three hummingbird-pollinated plants, Palicourea demissa, Mezobromelia capituligera, and Kohleria affinis, were measured. These flowers occur and were studied in the southern section of the Chocó-Andean subtropical montane rainforest, in the Pichincha province of Ecuador. Flowers were bagged for 24 hours and sampled at approximate two-hour time intervals for 12 or 24 hours. Nectar concentration and sugar production …

Mammals Of The Northern Andes: An Analysis Of Camera Trap Data And Observation In Angochagua, Ecuador, Risa Berman

Independent Study Project (ISP) Collection

The high Andes of Ecuador are home to a diverse community of mammals, many of which are threatened. These include the Andean bear, Andean fox, puma, and mountain tapir. This study used camera traps, direct observation, and indirect observation over three weeks to monitor the wildlife in the mountains of the Parroquia of Angochagua. The five species observed during this period were Andean bear, Andean fox, dog, mountain paca, and mouse. While this short study did not completely survey the mammalian community of the area, it confirmed the presence, diet, sociality, temporal habits, elevational range, and habitat preferences of the …

A Survey Of Beetle Diversity (Order Coleoptera) On Lizard Island, John Mccormack

Independent Study Project (ISP) Collection

The beetles (order Coleoptera) of Lizard Island, a small granitic island on the mid shelf of the Great Barrier Reef, have never been assessed in the scientific literature. Prior to our work, only a single beetle genus had been documented on the island (Caryotrypes Decelle, 1968), based on a single specimen collected in 1993 (Reid & Beatson 2013). We conducted a survey of Lizard Island in April 2019 to determine which beetle families are present on the island and which families are the most diverse. The survey also assessed the beetle diversity in different habitats on the island and two …

Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen

Pomona Senior Theses

Keeping out invasive species may, upon first review, seem like a trivial environmental cry from ecologists and deep environmentalists; a belated wish to return to an undeveloped world where nature was pristine. However invasive species create problems that impact all of us and can have far more severe consequences than changing a stunning landscape. These problems are heightened in islands like Hawaii, where the fragile ecosystems have developed over centuries of evolution and adaptation. The introduction of a disease-carrying mosquito can put the people of Hawaii at risk to many vector-born illnesses and create an epidemic, taking human life. The …

The Ecology And Behavior Of Spring Migrating Indiana Bats (Myotis Sodalis), Piper Lee Roby

Theses and Dissertations--Animal and Food Sciences

Migration of animals has been studied for decades and has included everything from large terrestrial and pelagic mammals traveling thousands of kilometers to many types of birds flying through several countries to insects going through multiple life cycles in a single migration. The migration of bats has been studied in broad terms to gather coarse information such as distance traveled, connecting summer and winter habitat, and a general understanding of timing. However, only recently have researchers begun to understand the specifics of bat migration including physiology and fine resolution behavior.

Using nine years of spring migration data collected on VHF …

Testing The Competition-Colonization Trade-Off And Its Correlations With Functional Trait Variations Among Subtropical Tree Species, Yue Bin, Guojun Lin, Sabrina E. Russo, Zhongliang Huang, Yong Shen, Honglin Cao, Juyu Lian, Wanhui Ye

School of Biological Sciences: Faculty Publications

The competition-colonization trade-off, by which species can partition spatial niches, is a potentially important mechanism allowing the maintenance of species diversity in plant communities. We examined whether there was evidence for this trade-off among tree species in a subtropical forest and how it correlated with eight functional traits. We developed and estimated a metric for colonization ability that incorporates both fecundity and seed dispersal based on seed trap data and the sizes and distributions of adult trees. Competitive ability was estimated as survival probability under high crowding conditions based on neighborhood models. Although we found no significant relationship between colonization …

An Ecological Survey Of Forest Succession In A Northeast Ohio Ecosystem Following An Emerald Ash Borer Infestation, Joseph Haas

Williams Honors College, Honors Research Projects

This paper will be an ecological survey of a selected 28 acre piece of land in northeast Ohio impacted by the Emerald Ash Borer. This invasive species arrived in North America in 2002 and has since spread throughout the country wreaking havoc on the ash tree population. The purpose of this study is to determine what tree species are replacing the native ash trees in the succession of the forest. In order to achieve this goal, a section of the selected land will be blocked off and subdivided into manageable sections to facilitate data collection, namely the location of the …

Spatiotemporal Variability In Winter Severity: Consequences For White-Tailed Deer Populations And Habitat Sustainability, Grace Parikh

Dissertations, Master's Theses and Master's Reports

Winter in the northern Great Lakes presents a suite of challenging conditions for animals, in terms of limited food availability and increased energetic cost of locomotion and thermoregulation. Variable winter severity is liable to cause interannual fluctuations in habitat viability and use by animals, in addition to modulating physiological responses in animals to conserve energy. For example, white-tailed deer (Odocoileus virginianus) congregate at high densities under eastern hemlock (Tsuga canadensis) or northern white-cedar (Thuja occidentalis) stands, which provide forage, thermal cover, reduced snow depth, and enhanced vigilance. However, a suite of climatic, edaphic, and …

Plant Community Response To Novel Silvicultural Treatments In Great Lakes Northern Hardwoods, Stefan F. Hupperts

Dissertations, Master's Theses and Master's Reports

The objective of this dissertation is to assess plant community response across a range of silvicultural disturbances and test ecological hypotheses to better inform ecologists and forest managers. To provide context for the utility of revising silvicultural systems, I review natural disturbance regimes and historical practices that have shaped contemporary Great Lakes northern hardwood forests (Chapter 2). Further, I identify important ways to expand the silvicultural toolbox and better emulate natural disturbance regimes. Building on this theoretical underpinning, I investigate the initial regeneration and plant community response to two novel silvicultural experiments: the Northern Hardwood Experiment for Enhancing Diversity (NHSEED) …