Life Sciences Commons^™

Environmental Implications Of Modern Food Production: An Analysis For The Conscious Consumer, Jessica T. Coming

Cal Poly Humboldt theses and projects

This project explores the pathways by which agriculture affects the environment and determines which foods have the greatest climate, water, and land impacts. Agricultural effects on the environment are extensive, from loss of habitat and declines in regional biodiversity to disruption of global nutrient cycles and climate change. Global food production accounts for 26-34% of annual anthropogenic greenhouse gas emissions, makes up 38-46% of habitable land, and is responsible for 70% of freshwater extraction. The effect of agriculture on the environment is most significantly dictated by what type of food is being produced. Animal-based food products consistently have the highest …

C. Compactum Acts As A Comprehensive Climate Archive And Ecological Foundation In The Labrador Sea, Sadie Heckman

CMC Senior Theses

Clathromorphum compactum, a species of crustose coralline algae (CCA), is incredibly valuable for the future of high latitude ocean health, both as a comprehensive archive of changing ocean conditions, and ecologically as a foundational species for promoting biodiversity. Previous work establishes C. compactum as an effective climate proxy, and its life history provides several advantages for this use. C. compactum grow in nongeniculate, generally radial formations on hard substrates, over a wide distribution in mid-to-high latitude oceans and at subtidal depth ranges. Indeterminate growth leads to extreme longevity in C. compactum (Halfar et al., 2008), and growth rates are relatively …

Maximum Entropy Species Distribution Modeling For The Spring Ephemeral Herb Bloodroot (Sanguinaria Canadensis) In Eastern North America, Velan Manivannan

Williams Honors College, Honors Research Projects

The spring ephemeral plant Bloodroot (Sanguinaria canadensis) has a widespread native range in North America, spanning much of the eastern United States and Canada. While its current NatureServe conservation status is designated as ‘secure’ (NatureServe, 2023), its status as a spring ephemeral places it at a heightened risk for climate change-induced phenological mismatch with advancing forest canopy closure. Additionally, under continued anthropogenic climate change, Bloodroot may also experience range shifts or contractions as the edges of its present range warm past physiological thresholds. To determine the potential for range shifts and contractions under future warming, I generated a …

Developing Empirical Predictive Models To Support Conservation Planning For Threatened Frogs, Toads, And Turtles In South-Coastal California, Umarfarooq Adavudi Abdulwahab

All Graduate Theses and Dissertations, Fall 2023 to Present

Amphibians and reptiles (i.e., herptiles) are among the most threatened groups of species on Earth. The major threats to these species include the direct, indirect, and synergistic effects of habitat loss and fragmentation, invasive species, disease, overexploitation, and pollution. To protect and restore species, natural resource managers need effective, data-driven conservation plans that are grounded in sound knowledge of species distributions and habitat requirements. Species distribution models (SDMs) are popular tools used to assess species-habitat relationships. However, SDMs are sensitive to the choice and quality of input data, both of which can affect model accuracy and precision and lead to …

Phenology Of The Invasive Balsam Woolly Adelgid, Adelges Piceae (Ratz.) (Hemiptera: Adelgidae), On Subalpine Fir In Northern Utah, Elizabeth L. Rideout

All Graduate Theses and Dissertations, Fall 2023 to Present

Balsam woolly adelgid (BWA) is an invasive true fir pest in North America. Native to Europe, BWA was first discovered in Utah attacking subalpine fir in 2017. Recent BWA-caused subalpine fir mortality in northern Utah has prompted the need for baseline biological research to support pest management. Small-bodied and blending easily with its environment, BWA is a challenging pest to detect and study. Phenology, or the timing and characteristics of life stages through the year, of BWA varies depending on elevation and climate and is unstudied in Utah. This research focuses on defining aspects of BWA’s phenology, including the number …

Dephosphorylation Of Mpk6 And Mpk3 By Phosphatases Modulates Responses To Herbivory In Arabidopsis, Claire Teresa Hann

Theses and Dissertations

As sessile organisms, plants rely on extracellular signals and chemical responses to defend against stressors. Extracellular stress signals inducing defense responses originate both from biotic or abiotic threats, and from products of tissue damage or hormones. In defense against herbivores, essential responses include rapid generation of jasmonic acid (JA) at the wound site, followed by the global expression of genes that impede digestion and growth. Early defense gene expression amplifies JA production, while later JA-responsive gene expression causes the accumulation of defense products. MAP kinase (MAPK) pathways play a central role in mediating the perception of self, non-self, and hormonal …

Femoral Osteohistology In American Alligators (Alligator Mississippiensis) Reveals High Variation In Growth And Facilitates Interpretation Of An Early Pliocene Alligator, Davis Gunnin

Electronic Theses and Dissertations

Histological analysis of long bone thin sections is commonly used to infer growth rates and ecology of extinct vertebrates, particularly within Archosauria. However, most comparative neontological studies have used small samples of captive individuals, limiting the scope of variation. To fill this gap, 44 femoral thin sections of wild Alligator mississippiensis were prepared and analyzed. Comparison of slides revealed that larger individuals from cooler climates tend to show more LAGs compared to southerly A. mississippiensis of similar size, however, there is considerable variation. This pronounced variation in wild specimens emphasizes the need to use caution when interpreting paleohistological data with …

Effect Of In Situ Experimental Heating Of Artificial Mytilus Californianus Beds On Associated Invertebrate Communities In Northern California, Claire C. Windecker

Cal Poly Humboldt theses and projects

With the continued progression of climate change, the role of foundation species as mediators of temperature stress for species living on and within them has become increasingly important. In the intertidal zone, a major foundation species is the California mussel, Mytilus californianus, which can help to limit thermal stress for species that live among aggregations of these mussels. The ability of mussels to limit thermal stress as temperatures increase, however, is still unclear. This study sought to experimentally manipulate surface temperatures of artificial mussel beds in situ to examine the effects that increased surface heating at a single site …

Exploring The Effects Of Environmental Factors On Rice Blast Disease, April Ellen Lamb

Theses and Dissertations--Plant Pathology

Rice blast disease, caused by the ascomycete fungus Magnaporthe oryzae, occurs in over 85 countries and results in an annual crop loss of 10-30%, a corresponding nutrient value of meals for 60 million people. As a result, it is listed as a critical plant disease by the United Nations. Understanding factors affecting disease severity is of critical concern for food security. M. oryzae has been used as a model system for studying effector-triggered immunity (ETI) by understanding that ETI is primarily a plant response. M. oryzae has been used as a model to study fungal pathogenicity, host specificity, genome …

Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer

Cal Poly Humboldt theses and projects

A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …

Will Climate Warming Amplify The Competitive And Predatory Effects Of A Range-Expanding Marine Gastropod (Acanthinucella Spirata)?, Bailey N. Mccann

Cal Poly Humboldt theses and projects

The effects of climate warming on the distribution of range-expanding species are well documented, but the interactive effects of climate warming and range-expanding species on recipient communities remain understudied. For example, with climate warming, range-expanding species may become a threat to local biodiversity due to their relatively stronger competitive or predatory effects on potentially weakened, or less well-adapted recipient communities. Acanthinucella spirata is a predatory marine gastropod that has expanded its distribution north along the California coast since the Pleistocene via a poleward geographical range shift, tracking climatic warming. To assess whether A. spirata has stronger predatory effects on the …

Soil Moisture Mediated Behavioral And Physiological Alterations Of Coptotermes Formosanus And Reticulitermes Flavipes (Blattodea: Rhinotermitidae), Steven J. Richardson

LSU Master's Theses

Substrate moisture is a critical environmental factor for the survival and behavior of subterranean termites (Blattodea: Rhinotermitidae). The invasive Formosan subterranean termite (Coptotermes formosanus) and the native eastern subterranean termite (Reticulitermes flavipes) co-occur in the southeastern United States, but C. formosanus is predominant in subtropical and R. flavipes is more common in temperate regions. The difference in their geographic distributions is largely attributed to their different behavioral and physiological ecology. While ample research has been done on foraging behavior of the two species, there was no empirical evidence for the effects of constant soil moisture on …

Effects Of Spatial And Temporal Heterogeneity On The Genetic Diversity Of The Alpine Butterfly Parnassius Smintheus, Mel Lucas

Electronic Thesis and Dissertation Repository

Genetic diversity represents a population’s evolutionary potential, as well as its demographic and evolutionary history. Advances in DNA sequencing have allowed the development of new and potentially powerful methods to quantify this diversity. However, when using these methods best practices for sampling populations and analyzing data are still being developed. Furthermore, while effects of the landscape on spatial patterns of genetic variation have received considerable attention, we have a poorer understanding of how genetic diversity changes as a result of temporal variation in environmental and demographic variables. Here, I take advantage of advances in DNA sequencing to investigate genetic diversity …

Taxonomic And Phylogenetic Diversity Of Pitcher Plant Bogs In Georgia's Coastal Plain, Melanie Flood

Theses and Dissertations

Diversity studies via floristic survey and taxonomic metrics have proven essential for discerning community composition and biodiversity, however, phylogenetic analyses are necessary to reveal underlying evolutionary change and potential community assembly patterns. Pitcher plant bogs are highly diverse, highly understudied habitats that contain numerous listed and at-risk plant and animal species of Georgia.

In this study I investigated the taxonomic and phylogenetic diversity of pitcher plant bogs by asking the following questions:

1) What is the taxonomic diversity of pitcher plant bogs,

2) What is the dispersion of phylogenetic diversity within bog habitats, and

3) Does taxonomic and phylogenetic diversity …

Impacts And Dispersal Of Invasive Bivalves, Dreissena And Corbicula Spp., On Stream Benthic Communities, Darrin Scott Hunt

Wayne State University Dissertations

Asian clams (Corbicula spp.), zebra and quagga mussels (Dreisenna spp.) have invaded and spread throughout North American surface waters. Corbicula and Dreisenna species bio foul aquatic systems, occupy benthic substrates and degrade environments through shell deposition. I explored how Dreissena and Corbicula invasions affect benthic fish and macroinvertebrate communities, and examine how their impacts differ between urban and rural systems, and temperate and tropical climates. Macroinvertebrate and fish communities were evaluated at sites with increasing shell densities in the Rouge, and Huron rivers (MI, USA) using the United States Environmental Protection Agency’s Rapid Bioassessment Protocols (RBP). Urban and rural macroinvertebrate …

Understanding Caribou Population Cycles, Jack R. St. John

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The complex population dynamics of caribou (Rangifer tarandus) were studied to determine the patterns of their population cycles and the processes driving them. It is well established, via previous archaeological research and Indigenous knowledge, that large migrating caribou herds found in and around the tundra at northern latitudes experience population boom and busts roughly every several decades. However, the processes driving the dynamics of these cycles are relatively unknown, which makes managing caribou herds for recreational and subsistence harvests difficult. It has been hypothesized that a combination of intrinsic and extrinsic factors shape these cycles, with density-dependence, predation, …

Activity Patterns Of The Del Norte Salamander (Plethodon Elongatus): Monitoring Plethodontid Behavior Using Pit Tag Surveys, Sabrina Horrack

Cal Poly Humboldt theses and projects

Semi-fossorial plethodontid salamanders exhibit behavioral plasticity to avoid desiccation, retreating underground to shelter from adverse conditions such as low precipitation and high temperatures. In this study, I used passive integrated transponder (PIT) tag surveys to monitor this behavior in the Del Norte salamander (Plethodon elongatus), a small plethodontid native to northwestern California and southwestern Oregon. Within its range, a climatic gradient exists in which coastal areas experience milder temperatures and high precipitation, while inland areas tend to have colder winters, hotter summers, and lower precipitation. By monitoring the activity patterns of this species in inland and coastal areas, …

Climate And Soil Moisture Dynamics Inform Potential Climate Change Impacts On Available Moisture And Juvenile Tree Survival In Semiarid Forests, Carolyn R. Koehn

UNLV Theses, Dissertations, Professional Papers, and Capstones

Trees in semiarid forests and woodlands of the western United States need soil moisture to transpire and function. Juvenile trees are especially vulnerable during periods of low soil moisture as their rooting zones are smaller and shallower than those of adult trees. This thesis focuses on two soil moisture-driven aspects of semiarid forests that may be modified by climate change: seasonal soil moisture patterns and juvenile tree survival.

In chapter 1, I investigated the influence of precipitation on soil moisture across seasons, elevations, soil layers, and periods of low and high precipitation. I developed time-varying definitions of winter (snow accumulation), …

A Crisis Of Kelp, Rachel L. Sherman

Capstones

Along with insects and lab-grown meat, for years seaweed has been lauded as a sustainable “food of the future” by the U.N. Food and Agricultural Organization. As the world increasingly turns to alternative foods in pursuit of a healthier Earth, seaweed has all the makings of an ecological savior. It’s plentiful — seaweeds and ocean algae make up roughly nine tenths of all the plant life on Earth — it’s cheap to harvest and get to market, packed with nutrition, and keeps oceans clean, absorbing more carbon dioxide and releasing more oxygen than the world’s rainforests.

But outside of Japanese …

Reconstructing Carbon Dynamics Of Alpine And Temperate Zone Lakes Using Stable Isotopic Analysis, Rebecca M. Doyle

Electronic Thesis and Dissertation Repository

Lake sediments integrate signals from the catchment, atmosphere and water column, offering a unique window through which to view changes in the carbon cycle. Carbon dynamics in lakes are changing due to nitrogen loading and anthropogenic climate warming (ACW), threatening the water quality of lakes. This thesis identifies how the carbon dynamics of lakes have responded to anthropogenically-driven forcings by comparing pre- and post- AD 1850 records preserved in lake sediments. First, the carbon dynamics of Barry Lake (Ontario, Canada), a low-elevation temperate lake, are investigated. Effective moisture (the net of water inputs and evaporation) is reconstructed using the carbon …

Understanding The Influence Of Changing Climate On Mycotoxin Contamination Of Food And Indoor Fungi-Mediated Respiratory Illness, Mayomi Helen Omebeyinje

Theses and Dissertations

Over the years, climate change has been a major core issue in public and environmental health. The World Health Organization (WHO) estimated that about 250,000 additional death per year would be attributed to climate change between 2030 and 2050 if this situation persists. Since our population depends on (but not limited to) the availability of clean water, good air quality, and exposure to environmental hazards/pathogens, the overall health impact caused by climate change is likely to be overwhelming in the nearest future. This dissertation explored the influence of climate change on fungi diseases and pathogenesis after severe weather conditions (hurricanes …

The Whelming Sea, Sean Hanley

Theses and Dissertations

The Whelming Sea is a thirty-minute experimental documentary that reveals the moments of entanglement between three animals living along the Mid-Atlantic shoreline; curious humans, spawning horseshoe crabs, and migratory shorebirds. Working from the realm of multispecies ethnography, the film shifts the subjective positioning of the viewer between the human and nonhuman to suggest the complexity of our enmeshed experience. In the face of this current era of mass extinction, the film explores the limitations and poetic possibilities of scientific encounters with the lives of others.

Temporal Changes In Unisexual And Sexual Ambystoma Salamander Populations In Southeast Michigan, Kelsey B. Mitchell

Master's Theses and Doctoral Dissertations

Climate change drives changes in organisms’ geographic ranges that can lead to shifts in population structure. Unisexual (all female) Ambystoma salamanders reproduce via kleptogenesis, resulting in ploidy-variable offspring. I analyzed genetic data of historic and modern-day unisexual and A. laterale samples from the University of Michigan’s E. S. George Reserve using epidermal cell nuclei measurements and microsatellite loci. I found that population composition has shifted away from the more northern-distributed A. laterale and toward populations dominated by unisexuals in five out of six ponds. There was a significant relationship between the proportion of A. laterale to unisexuals and pond size …

Microcystins And Liver Disease Mortality, Insights From An Ecological Study, Rajesh Tirpaul Melaram

Walden Dissertations and Doctoral Studies

Microcystins (MCs) are toxic secondary metabolites produced by freshwater cyanobacteria. Algal bloom subsidence can stimulate MC release, which can impair liver function if orally exposed to in large doses. The purpose of this retrospective, U.S. ecological study was to determine if MC exposure represented an environmental risk factor for liver disease mortality using a socioecological approach. A longitudinal ecological substudy investigated the association between average total MCs in Lake Washington and Lake Manatee and age-adjusted chronic liver disease (CLD)/cirrhosis death rates in Brevard County and Manatee County, Florida (FL). A prediction model of total MCs was deduced by quantifying levels …

A Comparative Spatial And Climate Analysis Of Human Granulocytic Anaplasmosis And Human Babesiosis In New York State (2013-2018), Collin J. O'Connor

Legacy Theses & Dissertations (2009 - 2024)

Human granulocytic anaplasmosis (HGA) and human babesiosis are tick-borne diseases spread by Ixodes scapularis (the blacklegged or deer tick) and are the result of infection with Anaplasma phagocytophilum and Babesia microti, respectively. In New York State (NYS), incidence rates of these diseases increased concordantly until around 2013, when rates of HGA began to increase more rapidly than human babesiosis, and the spatial extent of the diseases diverged. Surveillance data of tick-borne pathogens (2007 to 2018) and reported human cases of HGA (n=4,297) and human babesiosis (n=2,986) (2013 to 2018) from the New York State Department of Health (NYSDOH) showed a …

Competition, Climate, And Drought Effects On Tree Growth In An Encroached Oak Woodland In Northern California, Jill J. Beckmann

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana Douglas ex Hook.) is experiencing increasing competition from Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) across its range at the same time as climate models are predicting increasing climate variability, including drought. Management recommendations that consider competition dynamics between these species under a changing climate are therefore needed for oak woodlands, but we do not currently understand the combined effects of competition, climate, and drought in this ecosystem. This research examines radial tree growth and drought response in Oregon white oak and Douglas fir in an encroached oak woodland near Kneeland, California. Stem maps …

Spatiotemporal Diversity Of Alpine Snow Algae Communities In The Pacific Northwest, Rachael C. Mallon

WWU Graduate School Collection

Snow algae are the dominant primary producers of snowy alpine environments and have recently been thrust into the public spotlight for contributing to glacial melt by decreasing snow albedo. These microbial communities are subject to extreme temperature regimes, high irradiance, low nutrient levels, and freeze-thaw cycles on daily, seasonal, and even long-term climatological changes. Although snow algae have been described on every continent, the spatiotemporal diversity of snow algae communities across snowy habitats has not been addressed. The natural geography and climate of the Pacific Northwest provides diverse snowy alpine ecosystems to study the effects of latitude, elevation, and precipitation …

Sociodemographic And Climatic Factors Shaping The Development Of Drought Policies In Major U.S. Cities, Riana S. Gayle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In most parts of the world, drought is an inevitable and natural occurrence. However, as the climate continues to warm, and populations grow and expand, the negative impacts of this extreme weather event are predicted to become more pronounced. This leads many communities and stakeholders to question what is being done to prepare society for widespread drought? The following research determines different social and atmospheric characteristics that affect a city’s likelihood of having a drought policy in place.To do this, a thorough search was conducted at the city level to determine where drought policies are currently located in theU.S. The …

Using Passive Acoustics To Infer Spawning Behavior And Phenology: A Case Study Of Haddock On Georges Bank, Elizabeth Mcdonald

Theses - ALL

Climate change has the potential to impact many aspects of an organism’s biology, including phenology, the timing of important biological events. The timing of reproduction and spawning events for commercially important fish species is a critically important area of research for fisheries management. Haddock (Melanogrammus aeglefinus) are commercially important as well as sound-producing, which allows for monitoring via non-invasive passive acoustics. This study presents an application of passive acoustic monitoring to a multi-year dataset to increase understanding of haddock sound production, as well as trends in spawning phenology and behavior. An automatic acoustic detector was able to identify haddock calls …

An Empirical Analysis Of Climatic, Geographic, And Cultural Determinants Of International Tourism, Ethan Straus

Honors Theses

Each year, billions of people visit different countries all around the world. For many of those countries, tourism is their primary industry, leading to millions of jobs and dollars in revenue. It is expected that by 2020 total International Tourism Receipts will reach 2 trillion US dollars annually. Currently, tourism employs an estimated 200 million people around the world. With the continued progression of climate change, the tourism industry is facing a newfound threat. Global temperatures and the seal level are both expected to rise significantly by the end of the century. Additionally, the Intergovernmental Panel on Climate Change has …