Life Sciences Commons^™

Spruce Budworm Defoliation Dynamics And Its Influence On The Acadian Forest, Cen Chen

Electronic Theses and Dissertations

Spruce budworm (SBW; Choristoneura fumiferana (Clem.)) is the primary forest defoliator in North America. SBW defoliation has affected tens of millions ha of forests during its periodic outbreaks and caused severe growth reduction and mortality of spruce-fir (Picea-Abies) species. Evaluating these damaging effects of SBW defoliation requires understandings of the variation and dynamics of defoliation, as well as trees' variable responses to defoliation in consideration of various tree- stand-, and site-level factors. In this dissertation, we developed statistical models to 1) evaluate influences of SBW defoliation on spruce-fir stand dynamics of annual volume net growth, mortality, …

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 …

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 …

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 …

Optimizing Water Quality And Temperature Parameters To Increase Survival Rates Of Anotheca Spinosa (Anura: Hylidae) Eggs At The El Valle Amphibian Conservation Center, Morgan Oestereich

Independent Study Project (ISP) Collection

Amphibians globally are facing extinction due to the fungus Batrachochytrium dendrobatidis (Bd). This has resulted in a worldwide push for increased conservation efforts. These efforts include those of the El Valle Amphibian Conservation Center (EVACC) in El Valle de Antón, Panama, where captive assurance colonies of many native amphibian species are housed. Among these species is Anotheca spinosa, a species of tree frog native to mountainous regions of Central America. This study was performed to analyze the relationship between water quality parameters and egg survival and reproductive success of EVACC’s captive population of A. spinosa and assess how related husbandry …

Foraging Behavior In Atta Leaf-Cutter Ants: A Comparison Of Disturbed Versus Undisturbed Nests, Ariana Baetz

Independent Study Project (ISP) Collection

The genus of ant, Atta, is one of the most prolific and ecologically impactful genera in the subfamily of Leaf-Cutter ants. They prefer to build nests and forage in disturbed areas or on the borders between secondary forest and disturbed areas, as much of their preferred harvest is cultivars. Two nests of Atta were studied at the La Hesperia Nature Reserve, one an undisturbed nest aged about four years and one a recently disturbed nest aged about seven years. General foraging behaviors were observed and compared for both nests, including peak foraging hours, headwidth of foraging ants, trail length, plants …

Historical Population Increases And Related Inciting Factors Of Agrilus Anxius, Agrilus Bilineatus, And Agrilus Granulatus Liragus (Coleoptera: Buprestidae) In The Lake States (Michigan, Minnesota, And Wisconsin), Robert A. Haack, Toby Petrice

The Great Lakes Entomologist

Three native species of tree-infesting Agrilus have regularly reached outbreak levels in the Lake States (Michigan, Minnesota, and Wisconsin), including A. anxius Gory (bronze birch borer), A. bilineatus (Weber) (twolined chestnut borer), and A. granulatus liragus Barter & Brown (bronze poplar borer). The main host trees for these Agrilus are species of Betula for A. anxius, Castanea and Quercus for A. bilineatus, and Populus for A. granulatus liragus. Based on 197 annual forest health reports for Michigan (1950–2017, 66 years), Minnesota (1950–2017, 64 years), and Wisconsin (1951–2017, 67 years), A. bilineatus was the most often reported Agrilus …

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 …

Comparison Of The Survival And Growth Of West Gulf Coastal Plain Pine In East Texas, Jamie Hooker

Electronic Theses and Dissertations

West Gulf Coastal Plain provenance loblolly (Pinus taeda L.), longleaf (Pinus palustris Mill.), shortleaf (Pinus echinata Mill.), and slash pines (Pinus elliottii Engelm.) were planted in East Texas to compare initial growth and survival. Containerized seedlings were planted in December 2015 on three study sites in Shelby, Houston, and Cherokee counties using a randomized complete block design. Seedlings were measured in January-February 2016 and again January-February 2017, January 2018, and January 2019. Three years after planting, survival was best (76.4%) in Houston County and was lowest in Cherokee County (26.4). Damage by Texas leafcutter ants (Atta …

The Effect Of Prescribed Burning On Wood-Decay Fungi In The Forests Of Northwest Arkansas, Nawaf Ibrahim Alshammari

Graduate Theses and Dissertations

Prescribed burning is defined as the process of the planned application of fire to a predetermined area under specific environmental conditions in order to achieve a desired outcome such as land management. This project used both morphological and molecular methods to identify and characterize the wood-decay fungi associated with the forests of northwest Arkansas—Pea Ridge National Military Park, Devil’s Den State Park, and the Buffalo National River—through frequent visits made between February 2018 and February 2019. In addition, in order to assess the effects of prescribed burning, incubation chambers were used to compare the growth of fungi from both unburned …

Decadal Effects Of Thinning On Understory Light Environments And Plant Community Structure In A Subtropical Forest, Ho-Chen Tsai, Jyh-Min Chiang, Ryan Mcewan, Teng-Chiu Lin

Ryan McEwan

Canopy-opening disturbance such as thinning has immediate and substantive effects on understory microclimate and therefore the establishment and growth of understory plants. A large number of studies have reported the effects of thinning on tree growth, but few studies have examined long-term effects of thinning on understory light environments and species and functional diversity of understory plants. Even less is known whether the change in understory plant community structure observed following canopy disturbance is short-lived and would diminish as the canopy closes or a long lasting due to legacy effects. We examined the effects of an experimental removal of 25% …

Varieties Of The Highly Dispersible And Hypervariable Tree, Metrosideros Polymorpha, Differ In Response To Mechanical Stress And Light Across A Sharp Ecotone, Jill M. Ekar, Donald K. Price, Melissa A. Johnson, Elizabeth A. Stacy

Life Sciences Faculty Research

Premise: The drivers of isolation between sympatric populations of long‐lived and highly dispersible conspecific plants are not well understood. In the Hawaiian Islands, the landscape‐dominant tree, Metrosideros polymorpha, displays extraordinary phenotypic differences among sympatric varieties despite high dispersibility of its pollen and seeds, thereby presenting a unique opportunity to investigate how disruptive selection alone can maintain incipient forms. Stenophyllous M. polymorpha var. newellii is a recently evolved tree endemic to the waterways of eastern Hawai'i Island that shows striking neutral genetic differentiation from its ancestor, wet‐forest M. polymorpha var. glaberrima, despite sympatry of these forms. We looked for evidence for, …

Synthesizing Conservation Motivations And Barriers: What Have We Learned From Qualitative Studies Of Farmers’ Behaviors In The United States?, Pranay Ranjan, Sarah P. Church, Kristin Floress, Linda S. Prokopy

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

Since 2011, qualitative studies examining adoption of conservation practices and programs (CPPs) have burgeoned. This article presents a systematic review of all U.S.-based qualitative investigations into CPP adoption since 1996. We found three themes are discussed primarily as motivating adoption: farmer characteristics, environmental awareness, and trust in information sources. Four themes are discussed primarily as barriers to adoption: farm management, negative perceptions of a conservation practice, perceptions that adoption is a risk, and land tenure. Four themes were discussed as both motivations and barriers: economic factors, social norms, perceptions of government programs, and farm characteristics. Overall, we found farmers’ economic …

Economic Contribution Of The Agricultural Sector To The Arkansas Economy In 2017, Leah English, Jennie Popp, Wayne Miller

Research Reports and Research Bulletins

Agriculture and associated agricultural activities are major contributors to the Arkansas economy. Agriculture is defined as the sum of agricultural production and processing activities, unless otherwise specified, and includes crop and animal production and processing, agricultural support industries, forestry and forest products, and textile goods. Agriculture contributes to the economy through direct agricultural production and value-added processing, and also leads to economic activity in other parts of the economy. This report is the eleventh in a series of reports examining agriculture’s economic contribution to the Arkansas economy. The total economic contribution of agriculture (direct, indirect, and induced effects) on value …

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 …

Habitat Characteristics And Selection By Ornate Box Turtles In The Sandhills Of South Dakota, Daniel W, Uresk, Alessandra Higa

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

The ornate box turtle (Terrapene ornata Agassiz) is a species of greatest conservation need in South Dakota. Habitat loss through agricultural development and fragmentation is the main threat to the species throughout its range, which extends from Wisconsin and northern Indiana through the central Great Plains, and from southern South Dakota to Arizona, northern Mexico, and the Gulf Coast of Texas. The objectives of this study were to determine the ornate box turtle’s preferred vegetation characteristics (microhabitat) compared to the available habitat (macrohabitat) on the Pine Ridge Reservation, South Dakota Sandhills region, during 2010–2011. In both years, using a modified …

Microbial Abundance And The Pattern Of Escherichia Coli Antibiotic Sensitivity And Resistance In Deer Creek And The Potential Impact Of A Veterinarian Hospital’S Input, Sarah Boxer, Tim Gsell

Research Days

The gram-negative bacteria, E. coli, is an indicator of fecal input for both point and non-point source origin. The veterinarian hospital located on Deer Creek may contribute to high antibiotic levels, which are known to select for resistant strains of bacteria living in impacted waters. The water running north of the veterinarian hospital was considered potentially antibiotic influenced as it was downstream of the site. The origin of the stream and sites upstream from the hospital were considered influent water. Sediments were also collected from these sites to determine if more long term resident E. coli were present with elevated …

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 …

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 …

A Preliminary Study For The Future Translocation Of A Saimiri Sciureus Troop From Sumak Allpa To Yasuní National Park: Assessing The Habitat Use, Population, And Behavior Of A Common Squirrel Monkey Troop In Indillama, Kenia French

Independent Study Project (ISP) Collection

Sumak Allpa, an organization specializing in primate rehabilitation, plans to introduce a Common Squirrel Monkey Troop ( Saimiri sciureus ), the Yasuní Troop, to the Indillama region of Yasuní National Park. This study analyzes the habitat use, population, and behavior of the Saimiri sciureus troop, referred to as the Indillama Troop, already existing in the region, from April 14th to May 4th, 2019. Focal and scan observation techniques were used to observe the troop’s behavior, and EasyTrails on an iPhone 7 was used to record GPS data. EasyTrails was also used to map the trail system in the Indillama region. …

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 …

Using Multi-Indices Approach To Quantify Mangrove Changes Over The Western Arabian Gulf Along Saudi Arabia Coast, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Jingjing Li, K. P. Manikandan, Thomas Piechota

Mathematics, Physics, and Computer Science Faculty Articles and Research

Mangroves habitat present an important resource for large coastal communities benefiting from activities such as fisheries, forest products and clean water as well as protection against coastal erosion and climate related extreme events. Yet they are increasingly threatened by natural pressure and anthropogenic activities. We observed an inaccurate distribution of mangroves over the Western Arabian Gulf (WAG) which is a vital habitat and resource for the local ecosystem, according to the United Stated Geological Survey (USGS) mangrove database through spectral analysis. Change detection analysis is conducted on mangrove forests along the Saudi Arabian coast of the WAG for the years …

Hillslope Hydrology In Global Change Research And Earth System Modeling, Y. Fan, M. Clark, D. M. Lawrence, S. Swenson, L.E. Band, S. L. Brantley, P. D. Brooks, W. E. Dietrich, A. Flores, G. Grant, J.W. Kirchner, D. S. Mackay, J. J. Mcdonnell, P. C. D. Milly, P. L. Sullivan, C. Tague, H. Ajami, N. Chaney, A. Hartmann, P. Hazenberg, J. Mcnamara, J. Pelletier, J. Perket, E. Rouholahnejad‐Freund, T. Wagener, X. Zeng, E. Beighley, J. Buzan, M. Huang, B. Livneh, B. P. Mohanty, B. Nijssen, M. Safeeq, C. Shen, W. Van Verseveld, J. Volk, D. Yamazaki

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

Earth System Models (ESMs) are essential tools for understanding and predicting global change, but they cannot explicitly resolve hillslope‐scale terrain structures that fundamentally organize water, energy, and biogeochemical stores and fluxes at subgrid scales. Here we bring together hydrologists, Critical Zone scientists, and ESM developers, to explore how hillslope structures may modulate ESM grid‐level water, energy, and biogeochemical fluxes. In contrast to the one‐dimensional (1‐D), 2‐ to 3‐mdeep, and free‐draining soil hydrology in most ESM land models, we hypothesize that 3‐D, lateral ridge‐to‐valley flow through shallow and deep paths and insolation contrasts between sunny and shady slopes are the top …

Phylogenetic And Biogeographic Controls Of Plant Nighttime Stomatal Conductance, Kailiang Yu, Gregory R. Goldsmith, Yujie Wang, William R. L. Anderegg

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The widely documented phenomenon of nighttime stomatal conductance (g_sn) could lead to substantial water loss with no carbon gain, and thus it remains unclear whether nighttime stomatal conductance confers a functional advantage. Given that studies of g_sn have focused on controlled environments or small numbers of species in natural environments, a broad phylogenetic and biogeographic context could provide insights into potential adaptive benefits of g_sn.

We measured g_sn on a diverse suite of species (n = 73) across various functional groups and climates‐of‐origin in a common garden to study the phylogenetic and biogeographic/climatic controls …

Occam's Razor Vol. 9 - Full (2019)

Occam's Razor

No abstract provided.