Terrestrial and Aquatic Ecology Commons^™

Soil Microbial Diversity And Litter Decomposition Increase With Time Since Land Use Disturbance In Tropical Montane Forests Of Malaysian Borneo, Renee Sniegocki

Graduate Theses and Dissertations

Logging and forest conversion are occurring at alarming rates in the tropical forests of Southeast Asia. These disturbances alter soil chemistry, microbial diversity, and disrupt carbon cycling through shifts in litter decomposition. Direct links between microbial diversity and soil properties such as pH are well established; however, the indirect impacts of logging and forest conversion on microbial diversity and litter decomposition are poorly understood. We used surface (5 cm) soil to assess soil physicochemical properties, next-generation DNA sequencing to assess soil microbial diversity, and standardized litterbags to assess litter decomposition stabilization at five sites along a land use disturbance gradient …

Can Desert Mosses Hide From Climate Change? The Ecophysiological Importance Of Habitat Buffering & Water Relations To A Keystone Biocrust Moss In The Mojave Desert, Theresa Ann Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

Empirical and observational studies suggest a keystone biocrust moss, Syntrichia caninervis, may be sensitive to future climate change in the American Southwest due to its uniquely sensitive water relations that appear particularly challenged during summer hydration-desiccation cycles. However, the potential mitigating roles of habitat buffering, acclimatization, and winter recovery on the vulnerability of this species remain largely unexplored. I investigated potential abiotic and biotic resiliency factors driving summer stress resistance and recovery in S. caninervis along present-day aridity gradients in the Mojave Desert to strengthen the climate change vulnerability assessment for this species common to biocrusts of North America, northern …

Investigating The Effects Of Sea-Level Rise And Increasing Salinity On Procambarus Lunzi Of Sapelo Island, Georgia, Samuel Long

Biology Theses

Barrier islands have great ecological and economical importance and face a threat from increasing sea-level due to climate change. Erosion of existing freshwater lens and ocean inundation could greatly change freshwater availability on the island. This could have significant impacts on freshwater crayfish like Procambarus lunzi, which are complexly intertwined into the trophic food web of the island. This study’s goal was to investigate the salinity tolerance of this crayfish on Sapelo Island, Georgia, in an attempt to predict the possible effects and response to sea-level rise by this crayfish. Crayfish were wild-caught from the island in March, June, and …

The Effect Of Ocean Plastic On Plankton And Marine Ecosystems, Aiden Brinkmann '22, Eric Shackelford '22

Student Leadership Exchange (SLX)

Title: The Effect of Ocean Plastic on Plankton and Marine Ecosystems Abstract: This presentation aims to raise awareness for the harm plastics in our oceans are causing analysis and visualization of scientific data. It is largely inspired by the fourteenth United Nations Sustainable Development Goal: Life Below Water. The datasets used primary fall into two categories: ocean plastic content statistics and plankton population demographics. The presentation will also explore plankton’s role as the base of many aquatic ecosystems and model the impact a population decline could have on these ecosystems. The effects ocean plastics can have on our modern society …

What Roadkills Did We Miss In A Driving Survey? A Comparison Of Driving And Walking Surveys In Baldwin County, Georgia, Kori A. Ogletree, Alfred J. Mead

Georgia Journal of Science

Accurate estimates of vertebrate road mortalities are necessary prior to the consideration of mitigation measures by resource managers. Due to ease of implementation, driving surveys are more common than walking surveys. From February 2018 to February 2019, two survey methods, driving and walking, were used to monitor a 1.16 km section of Highway 212 in Baldwin County, Georgia. Roadkills were identified and monitored for persistence from sunrise to noon two days a week. Twenty-nine roadkills were recorded over the survey period: 48.3% mammals (14/29), 27.6% herpetofauna (8/29), and 24.1% birds (7/29). Forty-eight percent (14/29) of roadkills were missed by the …

Re-Evaluation Of Euchloe Olympia (W. H. Edwards, 1871 (Pieridae: Pierinae) From A Geographic And Taxonomic Perspective, Harry Pavulaan

The Taxonomic Report of the International Lepidoptera Survey

The taxonomic status of regional populations of Euchloe olympia (W. H. Edwards, 1871) is reevaluated here. A review of pertinent literature and a critique of Clench & Opler (1983) are provided. The taxon rosa and two distinct populations of the Great Lakes “dune form” are each proposed for recognition at subspecific rank. The status of synonym anniha Ebner (1970) is addressed.

Impacts Of Invasive Rats And Tourism On A Threatened Island Bird: The Palau Micronesian Scrubfowl, Paul M. Radley, Robert A. Davis, Tim S. Doherty

Research outputs 2014 to 2021

Invasive predators have decimated island biodiversity worldwide. Rats (Rattus spp.) are perhaps the greatest conservation threat to island fauna. The ground nesting Palau Micronesian Scrubfowl Megapodius laperouse senex (Megapodiidae) inhabits many of the islands of Palau's Rock Island Southern Lagoon Conservation Area (RISL) in the western Pacific. These islands are also heavily visited by tourists and support populations of introduced rats, both of which may act as added stressors for the scrubfowl. Using passive chew-tag and call playback surveys on five tourist-visited and five tourist-free islands, we investigated if rats and tourists negatively affect scrubfowl, and if higher rat activity …

What Is The Winter Limiting Nutrient In Urban Reservoirs? A Case Study, Precious Nyabami

UCARE: Research Products

The importance of reservoirs is widely acknowledged by urban populations, yet little is understood scientifically about their ability to process nutrients deposited into them in winter. For example, when agricultural runoff is deposited in lakes in winter or any other season, eutrophication might arise in the spring. With increased eutrophication, several ecosystem services are lost and this leads to what several researchers call “the urban syndrome”. Some studies have been done on the winter limnology of lakes, yet little is understood about the above in reservoirs. The sustainability of urban reservoirs relies on understanding how the phytoplankton in urban reservoirs …

136— Predation On Microbivalves By Juvenile Naticid Gastropods On San Salvador Island, The Bahamas, Eliza Merges

GREAT Day Posters

Predator-prey interactions, where snails eat clams, evolutionarily has been a key interaction within marine molluscan communities. There is evidence of molluscan extinctions in the fossil record that are marked by changes in predation ratios. In this study, we will investigate predation of microbivalves by juvenile naticid gastropods in a shallow marine setting on San Salvador Island in the Bahamas. We propose to test predation density within different environments (facies) of a lagoonal setting. Significantly different ratios between these facies in one time period can indicate that predator-prey interactions can change over time from one environment to another. It is more …

135— Coral-Sponge Interactions On Rocky Point Reef, San Salvador, Bahamas, Michael Harvey, Anna Meichenbaum, Brooke Stickles

GREAT Day Posters

We surveyed the intensity of competition for reef space between sponges and corals at the Rocky Point patch reef adjacent to San Salvador Island, The Bahamas. Our working hypothesis was that, because of a dearth of predators, fast growing, chemically unprotected sponges more likely to be involved in competitive interactions. Results indicate that competition for reef space was widespread, but contrary to our hypothesis no sponge or coral species was disproportionately more involved in these interactions. These results contradict previous studies on Rocky Point reef and in our discussion we propose an explanation for this discrepancy.

170— A Comparison Of Native And Invasive Plant Species Microhabitats In Western Ny, Emelyn Bell

GREAT Day Posters

Previous research concluded that the extended leaf phenology of invasive plant species Lonicera maackii (Amur Honeysuckle) reduced seed predation, possibly due to less favorable microclimates for invertebrate seed predators. In the fall of 2019, we conducted a field experiment to observe the microhabitat preferences of snails. In our study, we selected six pairs of invasive L. maackii and native Cornus racemosa (Gray Dogwood) throughout the Roemer Arboretum. Twice weekly, we recorded temperature, relative humidity, air velocity, light, soil pH, and soil moisture along with the number and size of snails found on the plant and within 0.3m of its surrounding …

Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce

Publications and Research

Elevation is an important determinant of ecological community composition. It integrates several abiotic features and leads to strong, repeatable patterns of community structure, including changes in the abundance and richness of numerous taxa. However, the influence of elevational gradients on microbes is understudied relative to plants and animals. To compare the influence of elevation on multiple taxa simultaneously, we sampled phytotelm communities within a tropical pitcher plant (Nepenthes mindanaoensis) along a gradient from 400 to 1200 m a.s.l. We use a combination of metabarcoding and physical counts to assess diversity and richness of bacteria, micro-eukaryotes, and arthropods, and compare the …

Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen

LSU Doctoral Dissertations

The Mississippi River Delta is threatened by a growing pressure to support large human populations in the United States both with food production, navigation systems, and urban development in the Mississippi River Basin. Nitrate-nitrogen load in the Mississippi River, up to 100 Tg N yr^-1 from agricultural and urban runoff, leads to phytoplankton blooms and hypoxia across the Louisiana continental shelf, creating dead zones of low dissolved oxygen threatening a significant commercial fishery. Along the coast and river corridors, floodplain ecosystems have the capacity to retain and remove nitrate. This dissertation explores the role of productive, actively growing coastal …

An Ecopath With Ecosim Analysis On Offshore Petroleum Platform Influences On Gulf Of Mexico Red Snapper, Valentin Gomez

LSU Master's Theses

Offshore oil and gas platforms have had a significant presence in the Gulf of Mexico since the 1950s. An important secondary function of these structures is that they provide artificial habitat to fisheries, most notably Red snapper. Policy changes intended to reduce the risk associated with aging infrastructure have reduced the number of standing platforms from 4044 to 1867 from 2001 to 2018. The effect this loss of habitat has on Red snapper was tested by creating three scenarios of platform changes and modeling the perturbation from 2005 to 2050. The simulation was accomplished using the ecological model Ecopath with …

Developing Tadpoles Exhibit Metabolic And Organ Size Plasticity In Competitive Rearing Environments, Emma Kimberly

Undergraduate Honors Thesis Projects

Abstract

Plasticity is the ability of an organism to respond to environmental variation by expressing different phenotypes. In Red-eyed treefrog tadpoles, Agalychnis callidryas, competitive environments induce long guts and short tails. Despite having a larger gut, tadpoles reared with competition do not increase intake when food becomes available. Pilot data suggest that this is because they have lower metabolic rates. The ability to maintain a larger gut with a depressed metabolic rate is confusing because guts are energetically expensive, and suggests that another energetic trade-off is taking place. The purpose of this study was to investigate the effect of …

Combined Opportunistic And Equilibrium Life-History Traits Facilitate Successful Invasions Of The Shimofuri Goby (Tridentiger Bifasciatus), Jiao Qin, Miao Xiang, Meixiang Jia, Fei Cheng, Bjorn V. Schmidt, Jian Liu, Songguang Xie

Faculty Publications

The life-history traits of a non-native population of Shimofuri goby (Tridentiger bifasciatus) were investigated in Nansi Lake, which is a storage lake on the East Route of the South-to-North Water Transfer Project, China. The results were analyzed in combination with data from other non-native populations of this species to reveal the life-history traits that caused its successful invasions. Mature gonads in April and May suggest that the species spawns in this period, and cohort tracking and age analysis revealed that individuals had a one-year lifespan. The relative fecundity was 2,825 ± 614 eggs/g. A short lifespan and high fecundity are …

Nine-Mile Prairie Environs: Master Plan, April 2020, Center For Grassland Studies

Center for Grassland Studies: Newsletters

A red and white checkered water tower stands atop the hills on Lincoln’s northwest fringe. The tower sustains water pressure and is a waypoint finder for air traffic approaching the Lincoln airfield. In addition to these services, the tower’s checker pattern can symbolize the surrounding patchwork of native unplowed tallgrass prairie that comprises the Nine-Mile Prairie (NMP) Environs. At the core is NMP, a 230-acre public property full of tallgrass prairie biodiversity and Nebraska history. An area surrounding NMP, referred to as the “Environs” in the context of this strategic planning document, is almost entirely grassland or agricultural cropland. The …

Effects Of Stream Permanence On The Stoneflies (Plecoptera) Of The Mammoth Cave Region, Taylor Mcroberts

Masters Theses & Specialist Projects

Stoneflies (Plecoptera) are often associated with cold perennial streams, but many species also inhabit intermittent streams that experience reduced or lack of flow during summer and autumn. In this study the influence of stream permanence on stonefly assemblage composition and spatial distribution in the Mammoth Cave region, Kentucky, USA, was addressed based on a 14 month sampling regime from the fullest range of stream sizes and habitable flow regions available. Adult stoneflies were collected monthly at Mammoth Cave National Park and the Western Kentucky University Green River Preserve. Collections were done from December 2018–October 2019 using a standard timed protocol …

An Intergrative Ecological And Taxonomic Assessment Of The Stoneflies (Insecta, Plecoptera) Of The Black Mountains, North Carolina, Usa, Madeline Lake Metzger

Masters Theses & Specialist Projects

The Black Mountains are a part of the Blue Ridge region of the Appalachian Mountains and include Mount Mitchell, the highest peak east of the Mississippi River at 2,037 m (= 6,684 ft). A comprehensive inventory of the stonefly fauna was conducted between 2014-2019 within Mt. Mitchell State Park and adjacent Pisgah National Forest. Collections occurred seasonally from 44 unique locations, covering a broad range of stream sizes and elevations in the region. Sequencing of the mitochondrial cytochrome c oxidase subunit I (mtCOI) gene was completed to assist with making positive determinations to species for females of taxonomically challenging genera …

A Phenotypic Comparison Of Regional Populations Of Hemileuca Maia (Drury, 1773) With Designations Of New Subspecies (Bombycoidea, Saturniidae, Hemileucinae), Harry Pavulaan

The Taxonomic Report of the International Lepidoptera Survey

Following refinement of the type locality of Hemileuca maia to the Long Island Pine Barrens of New York State by the author (Pavulaan, 2020), an evaluation of phenotypic characters of regional populations of H. maia is presented. The Long Island population is the nominotypical subspecies. Populations in southeastern coastal New England and offshore islands are presently considered nominotypical maia. However, several continental inland populations show evidence of subspecific variation. Four new subspecies are designated. Detailed phenotypic information of other interior regions is lacking.