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Incorporating Native Plants In Insectary Strips To Promote Insect Diversity And Below-Ground Beneficial Microbes In South Texas, Lindsey N. Richards

Theses and Dissertations

Farm edges are generally the most undisturbed areas in a farm with diverse vegetation and can enhance agrobiodiversity and provide crucial food and shelter for wildlife, insects, and soil biota. Planting native wildflowers with the ability to reseed and withstand local climatic conditions for semi-permanent vegetation around farm edges or in between crops has potential to biologically control pests. To test this, we ran a two-year study and installed three different flowering insectary strips on a certified organic vegetable farm in South Texas during the winter season. The treatments were: 1) a commercially sourced 17-species native wildflower seed mix; 2) …

Population Demography, Spatial Ecology, And Habitat Use Of The Florida Box Turtle (Terrapene Bauri) On A Barrier Island, Michael D. Mills

USF Tampa Graduate Theses and Dissertations

Turtles are one the most threatened vertebrate groups in the world due to anthropogenic threats such as habitat loss and overexploitation. In addition to occupying a range that has been vulnerable to major habitat loss, the Florida box turtle (Terrapene bauri) is particularly at risk of overexploitation due to its popularity in the pet trade. Sanibel Island is a barrier island in southwest Florida that has experienced major habitat loss and is the site of a recent poaching event. In response to these threats, studies of both the population demography and spatial ecology were conducted on Sanibel’s Florida box turtle …

Biodiversity And Foraging Preferences Of Bee Communities At Pinnacles National Park Over Time, Abigail M. E. Lehner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bees are considered to be the most important animal pollinator, providing billions of dollars in pollination services each year. Despite their importance in both natural and agricultural settings, the status of most native bees is unknown. Native bees are subject to a variety of threats including habitat loss, pesticide use, and climate change. Yet, monitoring programs have been implemented in few natural areas. Pinnacles National Park, PNP, in California is one of the only natural areas to have a large historical dataset on bees across decades with surveys conducted in 1996, 1997, 1998, 1999, 2002, 2011, and 2012. These surveys …

Hidden Mechanisms Of Climate Impacts In Western Forests: Integrating Theory And Observation For Climate Adaptation, Sara J. Germain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fire, insects, and disease are necessary components of forest ecosystems. Yet, climate change is intensifying these tree stressors and creating new interactions that threaten forest survival. This dissertation combined field observations with statistical predictions of changing disturbances in western forests to identify 1) how conventional models may underestimate future forest loss, and 2) how positive relationships between trees may be exploited by managers to prevent forest loss.

In Chapter II, I tested whether increasingly extreme weather with climate change increases Pacific yew extinction risk. I found that conventional modeling methods underestimated local extinction risk because trees were adapted to a …

Distribution Of Carrion-Associated Beetles And Their Phoretic Mites Along An Urban-Rural Gradient In Northeast Alabama, Kennedy Norris

Theses

Global insect decline has been linked to urbanization, most notably by habitat fragmentation. These insects perform important ecological functions such as pollination, managing pests, and decomposing carrion to recycle nutrients back into the environment. Despite the importance of nutrient recycling behavior displayed by carrion-associated beetles, little research has been done on them in the southeastern US. Previous studies have found a relationship between urbanization, less favorable environmental conditions, carrion availability, and decreased insect diversity. However, no studies have been conducted in the southeastern United States on the relationship of these beetles to their environment despite having the highest rates of …

Molecular And Morphological Investigations Of Grouper (Serranidae) Biodiversity In Saudi Arabia, Mohammad Saeed Al Jazza Alqahtani

Theses and Dissertations

Chapter 1: The seas surrounding the Arabian Peninsula, which represent the northernmost portion of the Indian Ocean, are considered to have the highest aquatic biodiversity among the worlds marine regions. Seas that surround the Arabian Peninsula include the Red Sea, the Gulf of Aden, the Arabian Sea, the Gulf of Oman, and the Arabian Gulf. In aggregate, this area harbors a large number of endemic and more widespread marine species, including fishes, echinoderms, and corals.

There are unique challenges involved in grouper species identification in the Arabian region including ‘familiar’ Arabic species designations that are not standardized in the Arabic …

Effects Of Forest Restoration On The Recovery Of Dead Wood, Associated Arthropods, And Insect-Mediated Wood Decomposition, Estefania Fernandez Barrancos

Dissertations

Dead wood represents 8% of terrestrial carbon stocks and is an important source of habitat and food for decomposer and non-decomposer arthropods. However, anthropogenic disturbance reduces the amount of dead wood, putting at risk the presence of a habitat that is essential for many arthropods and other organisms that rely on it for food and shelter. Forest restoration aims to assist the recovery of ecosystems that have been damaged or destroyed and could be a means to recover both dead wood and its associated arthropod communities. This doctoral dissertation lies at the intersection of climate change, biodiversity loss and ecological …

Life After Death – Does Carcass Biodiversity Scale With Carcass Body Size?, Troy Warfield

Biological Sciences Undergraduate Honors Theses

Mammals play a large role in the ecosystems where some, especially large-bodied mammals, act as ecosystem engineers. Mammal carcasses, particularly those of large body mass act as a temporary island of dense nutrients that support other organisms, including other mammal species, for an extended period. Research in this field currently focuses on the link between mammal carcass size and nutrient availably or on non-mammalian size and biodiversity, but little is available on the correlation between mammal carcass size and its influence on ecosystem biodiversity. Here we ask, does the available biomass (i.e., body size) of the carcass affect its role …

The Consequences Of Climate Change For Native Bee Assemblages, Melanie R. Kazenel

Biology ETDs

Recent declines in terrestrial arthropod biodiversity highlight the need to pinpoint which taxa and ecosystem services are most threatened, and why. But, for most of the world’s ~20,000 bee species, we lack robust evidence of population trends, and the role of climate change remains surprisingly little studied. I used long-term bee monitoring data from the Sevilleta Long-Term Ecological Research Program (Socorro, NM, USA), along with complementary experimental and observational data, to examine how climate relates to bee abundance and diversity patterns over time and space, and to identify the traits that govern bees’ climate sensitivities.

Historical And Future Role Of Wilmar Palm Oil In Deforestation Of Indonesian Borneo, Sam Coroniti Iii

Senior Theses

Borneo is one of the most biologically diverse locations on Earth, with thousands of endemic and rare species forming unique and intricate relationships throughout the ecosystems. Orangutans, elephants, leopards, tigers, rhinos, and many more species call this island their home, although population levels for all of the mentioned species have been in seriously decline over recent decades. The loss of primary rainforest that provides the most critical habitat for these species has occurred at the highest rate that has ever been seen on Earth, leading to extreme land conversion and greenhouse gas producing operations. The primary driver of these actions …

Manipulating Species Diversity: Environmental Impacts In Row Crop, Livestock, And Grassland Agroecosystems, Alayna A. Jacobs

Theses and Dissertations--Plant and Soil Sciences

The diversity of living species in an agroecosystem affects both natural resources and agricultural production efficiency. The rise of managed plant monocultures has allowed agricultural yields to increase over time. However, simplifying agroecosystems affects the capacity of the system to sustainably provide clean air, water, and productive soils essential for continued food and fiber production. This dissertation manipulates species diversity in row crop and forage agroecosystems prevalent in the Eastern United States and tracks the associated environmental and agricultural production consequences.

In row crop agroecosystems, increasing plant diversity with winter cover crops has been suggested as a strategy to increase …

A Flora Of Coyote Ridge And Flat, Inyo County, California, Martin Purdy

CGU Theses & Dissertations

California’s Sierra Nevada mountain range contains a disproportionate share of the state’s plant diversity and is one of the most floristically diverse regions of its size in the United States. The high Sierra Nevada, in particular, has been identified as an important center of species richness and endemism within California. Anthropogenic climate warming is expected to disproportionately affect mountain ecosystems, and models have predicted serious habitat contraction and extirpation for many alpine plant taxa. A specimen-based inventory of the vascular and non-vascular plants of Coyote Ridge and Flat was conducted to establish baseline data for one such sensitive alpine and …

Conservation In Ecuador's Sangay-Podocarpus Connectivity Corridor: A Study Of Coproductive Capacities, Gabriel Isaac Oppler

Graduate Student Theses, Dissertations, & Professional Papers

Connectivity conservation, a growing topic across science, policy, and management, is considered an important supplement to protected areas. A diversity of ecological corridors is emerging to restore fragmented landscapes, preserve intact habitats, protect biodiversity, and improve resilience to climate change. Despite increasing expertise and resources for planning corridors, many initiatives face challenges mobilizing science and governance to implement corridors on the ground. In many cases, biophysical science is supplemented with social science to better understand the human elements of connectivity. Similarly, collaboration and partnership are heralded as essential for effective governance of corridors. However, less is known about how these …

Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels

Electronic Theses and Dissertations

Conventional agricultural practices can have unintended consequences on the environment and wildlife. Insects and birds are declining at rapid rates around the world, and the current conventional agricultural paradigm is a major driver through habitat loss and the intensification of production. Invertebrates in agroecosystems provide services to both farmers and the rest of society. Regenerative systems may promote the functioning of an agroecosystem by influencing invertebrate abundance, diversity, and ecosystem services and mitigate bird and insect declines through conservation practices that increase soil health, reduce disturbances, and increase biological diversity. Here I address knowledge gaps of the effects of regenerative …

Environmental Effects On Constructed Wetland Microbial Diversity And Function In The Context Of Wastewater Management, Sandrine Grandmont-Lemire

Cal Poly Humboldt theses and projects

Microbial communities play a crucial role in ecosystems, yet we know little about how microbial diversity influences ecosystem functioning. An important gap in our understanding is how environmental change affects microbial Biodiversity-Ecosystem Function relationships (BEF). These complex interactions between microbial biodiversity and ecosystem function can influence major biogeochemical processes, such as the nitrogen cycle in wetland ecosystems, which play an important role in managing wastewater. To address the effect of biodiversity on function, my study investigates the BEF relationships between microbial diversity and the function in terms of ammonia removal from wastewater at the Arcata Wastewater Treatment Facility (AWTF) both …

Effects Of Dissimilar Silvicultural Techniques On Small Mammal Communities In Michigan's Upper Peninsula, Breanna R. Gusick

Dissertations, Master's Theses and Master's Reports

Small mammal populations, and predators reliant upon them as food resources, are often challenged by conflicting objectives of timber production and maintenance of quality habitat. With over 70% of the landscape forested, and nearly one-third of the land privately owned, Michigan’s Upper Peninsula (UP) is a matrix of independent management strategies. To assess the effects of various silvicultural regeneration methods on small mammal populations in the Upper Peninsula, we trapped small mammals in experimental silviculture plots, whereby treatments varied by regeneration method (amount of residual canopy cover) and site preparation (i.e., control, tip-up, and scarification), and deer exclosures. We used …