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The Effect Of Disturbance And Freshwater Availability On Lower Florida Keys’ Coastal Forest Dynamics, Danielle E. Ogurcak

FIU Electronic Theses and Dissertations

Coastal forest retreat in the Florida Keys during the 20^th century has been attributed to a combination of sea level rise and hurricane storm surge impacts, but the interactions between these two disturbances leading to forest decline are not well understood. The goal of my research was to assess their effects over a period spanning more than two decades, and to examine the relationships between these press and pulse disturbances and freshwater availability in pine rockland, hardwood hammock, and supratidal scrub communities. Impacts and recovery from two storm surges, Hurricanes Georges (1998) and Wilma (2005), were assessed with satellite-derived …

Discovery And Delimitation: Criconematid Nematodes Of North American Grasslands, Magdalena Jean Olson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Approximately 200 years ago, North American landscapes were dominated by vast expanses of grassland. The Great Plains, an ecologically complex and diverse ecoregion, extended from Canada to the Gulf of Mexico, and from the Rocky Mountains to the border of the eastern hardwood forest in Indiana. Now the original tallgrass prairie exists in small widely dispersed remnant patches surrounded by agroecosystems. This study is an effort to characterize soil nematode diversity and population structure within those remnant patches. The plant parasitic nematode family Criconematidae serves as our indicator for nematode diversity, due to its global distribution, high abundance in natural …

Serpentine Ecosystem Responses To Varying Water Availability And Prescribed Fire In The U.S. Mid-Atlantic Region, Jessica Schedlbauer

Biology Faculty Publications

No abstract provided.

Acute Toxicity Of Β-N-Methylamino-L-Alanine (Bmaa) To Fathead Minnow (Pimephales Promelas) And Zebrafish (Danio Rerio), Jiayi Wang

School of Natural Resources: Dissertations, Theses, and Student Research

β-N-methylamino-L-alanine (BMAA) is a neurotoxic amino acid produced by most species of cyanobacteria. Exposure to BMAA has been hypothesized as a cause of ALS and possibly Parkinson’s and Alzheimer’s diseases for several decades. Both in vitro and in vivo experiments revealed that exposure to elevated concentrations of BMAA can damage motor neurons and cause motor dysfunctions. However, the exact mechanism of BMAA-induced neurotoxicity has not been well understood.

Based on the available literature and in spite of its water-soluble and non-protein nature, BMAA appears to be able to bioaccumulate in organisms. The ubiquity of cyanobacteria and the potential for bioaccumulation …

Isotopic Incorporation Rates And Discrimination Factors In Mantis Shrimp Crustaceans., Maya Devries, Carlos Del Rio, Tate Tunstall, Todd Dawson

Faculty Publications, Biological Sciences

Stable isotope analysis has provided insights into the trophic ecology of a wide diversity of animals. Knowledge about isotopic incorporation rates and isotopic discrimination between the consumer and its diet for different tissue types is essential for interpreting stable isotope data, but these parameters remain understudied in many animal taxa and particularly in aquatic invertebrates. We performed a 292-day diet shift experiment on 92 individuals of the predatory mantis shrimp, Neogonodactylus bredini, to quantify carbon and nitrogen incorporation rates and isotope discrimination factors in muscle and hemolymph tissues. Average isotopic discrimination factors between mantis shrimp muscle and the new diet …

The Ecological Significance Of Emerging Deltas In Regulated Rivers, Malia A. Volke, Michael L. Scott, W. Carter Johnson, Mark Dixon

Natural Resource Management Faculty Publications

Sedimentary deltas forming in the world’s regulated rivers are a glaring gap in our knowledge of dammed riverine ecosystems. Basic ecological information is needed to inform the current debate about whether deltas should be retained and managed to gain ecosystem services lost under reservoirs or whether they should be partially removed to improve flow conveyance and to resupply sediment-starved reaches below dams. An examination of nine deltas on the heavily regulated upper and middle Missouri River showed the following: The sizes, dynamics, and biotic communities vary widely across deltas; riparian forest has established on portions of most deltas; the current …

The Status Of Fishes In The Missouri River, Nebraska: Blue Sucker Cycleptus Elongatus, Kirk D. Steffensen, Sam Stukel, Dane A. Shuman

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Blue Sucker Cycleptus elongatus are a large-bodied, benthic fish that are considered an indicator species for riverine health. A combination of historic commercial fishing and anthropogenic modifications to riverine habitat led to blue suckers being listed as a candidate species for the federal threatened or endangered species list in 1993. However, they were never designated a federally protected species. Locally, Blue Suckers are currently listed as a Nebraska Natural Legacy Project’s Tier 1 species but population changes and trends have not been quantified. Therefore, the objective of this paper was to evaluate the current population status of Blue Sucker in …

Population Level Responses To Direct Application Liming In Gyrinophilus Porphyriticus, Shelby Renea Timm

Theses, Dissertations and Capstones

Direct application liming (DAL) has been used to neutralize acidified streams to restore aquatic biota. This mitigation technique has been used globally for decades, yet little data exist on its effects on amphibian populations. My study investigated the effects of liming on amphibians by measuring variability in life histories of larval Gyrinophilus porphyriticus. I collected larvae from six streams in the Monongahela National Forest, West Virginia. I examined the effects of DAL on age structure, and I failed to detect a treatment effect. I used ANCOVAs to examine differences in body condition, body size, and gape size. I observed that …

Ecohydraulic Investigation Of Diatoms In A Bedrock-Controlled Stream, Alex M. Rittle

Theses and Dissertations--Geography

Recent studies within the past decade or so have shown the importance of algae in geomorphic and hydrologic processes of lotic systems. However, the ecohydraulic role of algae in bedrock systems has largely been ignored. In addition, the utility of algae as indicators of channel dynamics have often been assumed by geomorphologists, but relatively few studies have examined this relationship. The purpose of this study was to determine whether algae, specifically diatoms, are useful indicators of channel geomorphological dynamics, and to examine if distinct habitats or biotopes typical in fluviokarst and bedrock systems provide unique habitat space for diatoms, and …

The Mismanagement Of Limulus Polyphemus In Long Island Sound, U.S.A.: What Are The Characteristics Of A Population In Decline?, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

Over the past 15 years, horseshoe crabs in Connecticut have gone from being considered a nuisance species to a species of Greatest Conservation Need in 2015. This has happened through first, its discovery as an economically important species, second through research of its ecological role in coastal estuaries, and third, through education of the public concerning its role in the environment and their own health. To manage horseshoe crab populations successfully requires long term monitoring, research and education. The use of annual or biannual trawl data trends to assess the success of management decisions is limited due to the high …

An Application Of Recreation Resource Assessment Techniques To Inform Management Action In An Urban-Proximate Natural Area, Ashley D'Antonio, Christopher Monz, Nell Larson, Amy Rohman

Christopher Monz

No abstract provided.

Recovery Potential Of The Mussel Communities In The Lower Section Of Big Walnut Creek, Jared B. Ellenbogen

Undergraduate Honors Thesis Projects

Since the enactment of the 1977 Clean Water Act, biologists have created numerous multimetric assessment tools to evaluate the biological integrity of water resources, using biological criteria. The integrity of Big Walnut Creek, Ohio, has been in flux since the 1955 construction of Hoover Dam, and while current water quality is high, mussel communities in the creek have yet to recover to historical levels. This study sought to determine the cause of the decline in the mussels in the lower section of the creek below the dam. Historical creek data, including a fish-based index of biotic integrity (f-IBI), invertebrate community …

Scales Of Resilience: Community Stability, Population Dynamics, And Molecular Ecology Of Brook Trout In A Riverscape After A Large Flood, Erin V. Rodgers

Antioch University Dissertations & Theses

Climate change in the northeastern United States currently and in future decadal predictions is characterized by warmer average temperatures and more frequent and intense storm events. Many aquatic organisms that thrive below a certain temperature threshold, such as brook trout, are being pushed towards their upper thermal limits, ultimately lowering their probability of survival and resilience to disturbance. In late-August and early-September 2011, Hurricane Irene and Tropical Storm Lee created an extended flood in the Delaware Water Gap region of Pennsylvania and New Jersey, as well as much of the northeast. This dissertation examines the effects of this flood on …