Terrestrial and Aquatic Ecology Commons^™

Physiology And Biochemistry Of The Tropical Seagrass Thalassia Testudinum In Response To Hypersalinity Stress And Labyrinthula Sp. Infection, Stacey Marie Trevathan-Tackett

UNF Graduate Theses and Dissertations

Seagrass meadows are essential to coastal ecosystems and have experienced declines in abundance due to a series of environmental stressors including elevated salinity and incidence of disease caused by the pathogen Labyrinthula sp. This thesis evaluated the dynamics between T. testudinum and Labyrinthula concerning the impacts of short term elevated salinity stress on the early stages of infection in Thalassia testudinum (Chapter 2) as well as the presence of anti-labyrinthulid secondary metabolites produced by the tropical seagrass (Chapter 3). The results showed that short term exposure to hypersalinity alters some cellular processes but does not necessarily lead to an immediate …

Community Structure And Secondary Production Of Aquatic Macroinvertebrates In Coastal Wetland Ponds Of The West Copper River Delta, Alaska, Following Tectonic Uplift, Ryan Glen Van Duzor

Master's Theses

The Great Alaska Earthquake of 1964 (magnitude 9.2) greatly altered the coastal landscape in southcentral Alaska and had particularly dramatic effects on the Copper River Delta (CRD), an ecologically and economically important area within the Chugach National Forest. The earthquake caused tectonic uplift (up to 3.5m) of the CRD coastal tidal marsh and transformed it into a perched freshwater marsh. Copper River Delta ponds, which are crucial habitat to a myriad of migrating songbirds, shorebirds, and waterfowl, are of particular interest to wildlife managers in the CRD and along the Pacific coasts of North, Central and South America. This study …

The River Continuum Redux: Aquatic Insect Diets Reveal The Importance Of Autochthonous Resources In The Salmon River, Idaho, Kathryn Vallis

Master's Theses

Along a river network, changes in the physical characteristics of a stream - changes articulated by the River Continuum Concept (RCC) - have been predicted to influence stream food webs, particularly the resources supporting aquatic macroinvertebrates. Although diets of macroinvertebrates can track resource availability along the longitudinal gradient of streams, insect diets were not assessed in the original RCC study; rather, insects were grouped into functional feeding groups (FFGs). In addition, global climate change is increasing the frequency and spatial extent of wildfire and beetle outbreaks throughout the western United States and could affect riparian vegetation and the amount of …

Abundance Of Eukaryotic Microbes In The Deep Subtropical North Atlantic, Danielle Morgan-Smith, Gerhard J. Herndl, Hendrik M. Van Aken, Alexander B. Bochdansky

OES Faculty Publications

The meso- and bathypelagic ocean comprises the largest habitat on earth, yet we know very little about the distribution and activity of protists in this environment. These small eukaryotes are responsible for controlling bacterial abundance in the surface ocean and are major players in the material and energy transfer of pelagic food webs. In this paper, we quantify microbial eukaryotes in the deep North Atlantic, as well as provide a basic characterization of eukaryote community changes through the water column. To this end, we counted organisms using 2 different approaches: (1) catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH, also …

Structuring Expert Input For A Knowledge-Based Approach To Watershed Condition Assessment For The Northwest Forest Plan, Usa, Sean N. Gordon, Kirsten Gallo

Institute for Sustainable Solutions Publications and Presentations

Assessments of watershed condition for aquatic and riparian species often have to rely on expert opinion because of the complexity of establishing statistical relationships among the many factors involved. Such expert-based assessments can be difficult to document and apply consistently over time and space. We describe and reflect on the process of developing a computer-based decision support application from expert judgments for assessing aquatic and riparian conditions over the 100,000 km2 managed by the US federal government under the Northwest Forest Plan. The decision support system helped structure and document the assessment process and provided consistency and transparency to the …

Salmon For Terrestrial Protected Areas, Chris T. Darimont, Heather M. Bryan, Stephanie M. Carlson, Morgan D. Hocking, Misty Macduffee, Paul C. Paquet, Michael H. H. Price, Thomas E. Reimchen, John D. Reynolds, Christopher C. Wilmers

Environment and Nature Conservation Collection

Although managers safeguard protected areas for migratory species, little consideration has been given to how migratory species might benefit parks. Additionally, whereas land‐sea connections are considered in management of protected areas, most effort has focused on reducing negative “downstream” processes. Here, we offer a proposal to promote positive “upstream” processes by safeguarding the seasonal pulse of marine nutrients imported into freshwater and riparian ecosystems by spawning migrations of Pacific salmon. Currently, high rates of fishing limit this important contribution to species and processes that terrestrial parks were designed to protect. Accordingly, we propose limiting exploitation in areas and periods through …

The River Discontinuum: Applying Beaver Modifications To Baseline Conditions For Restoration Of Forested Headwaters, Denise Burchsted, Melinda Daniels, Robert Thorson, Jason Vokoun

Center for Integrative Geosciences

Billions of dollars are being spent in the United States to restore rivers to a desired, yet often unknown, reference condition. In lieu of a known reference, practitioners typically assume the paradigm of a connected watercourse. Geological and ecological processes, however, create patchy and discontinuous fluvial systems. One of these processes, dam building by North American beavers (Castor canadensis), generated discontinuities throughout precolonial river systems of northern North America. Under modern conditions, beaver dams create dynamic sequences of ponds and wet meadows among free-flowing segments. One beaver impoundment alone can exceed 1000 meters along the river, flood the valley laterally, …

How Are The Torres Strait Islander's Traditional Hunting Practices Affected By The Current Rate Of Decline In Dugong And Sea Turtle Populations And The Australian Government's Co-Management Policies On Marine Preservation?, Katilyn Price

Department of Environmental Studies: Undergraduate Student Theses

This paper will attempt to identify the extent to which the Torres Strait Islanders traditional hunting practices have been disrupted by the overall decline in dugong and sea turtle populations, which has directly correlated to an increase in hunting restrictions put in place by the Australian Government. The traditional hunting of dugongs and sea turtles provides not only a food source, but brings prestige to the men who catch them and serves as an educational platform to teach the younger generations about their culture. There are many environmental threats that impact the populations of sea turtles and dugongs though the …

Is Orthoptera Abundance And Distribution Across A Small Grassland Area Affected By Plant Biomass, Plant Species Richness, And Plant Quality?, Caitlin Falcone

Department of Environmental Studies: Undergraduate Student Theses

The choice of a specific microhabitat represents a compromise among a number of different factors organisms use to monitor habitat suitability. Grassland vegetation structure can vary widely along environmental gradients over a relatively small area. This vegetation structure can have a large influence on habitat selection by grasshoppers (Orthoptera). However, it is not clear which vegetation characteristics are most important in determining grasshopper abundance. We found that plant biomass, plant species richness, and plant quality all have an effect on grasshopper abundance and distribution. We observe that these affects vary both within and among the two years of data collection. …

Communication For Mate Selection In Anurans: Dominant Frequency Versus Snout-Vent-Length, Shari Jean Kunert

Department of Environmental Studies: Undergraduate Student Theses

No abstract provided.

The Interaction Of Fire And Grazing In Oklahoma Artemisia Filifolia Shrubland, Stephen L. Winter

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

I. FIRE-RESILIENCY OF A NORTH AMERICAN ARTEMISIA (ASTERACEAE) SHRUB: IMPLICATIONS FOR RESTORATION OF A CRITICAL ECOSYSTEM PROCESS. Conclusions: Unlike most North American Artemisia shrub species, our research suggests that A. filifolia is highly resilient to the effects of fire. Therefore, use of prescribed fires for the restoration and maintenance of ecosystem processes and properties is appropriate in A. filifolia shrublands of the southern Great Plains in North America.

II. RESTORATION OF THE FIRE-GRAZING INTERACTION IN ARTEMISIA FILIFOLIA SHRUBLAND OF THE SOUTHERN GREAT PLAINS, NORTH AMERICA. Synthesis and applications. Vegetation structure in Artemisia filifolia shrublands of our study were readily altered …

Reconstructing Species Responses To Past Climatic Changes Using Niche Modeling And Genetic Data, Tereza Jezkova

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glacial – interglacial cycles have a pronounced impact on species distributions and genetic structure. Many species shift their distributions to lower latitudes and altitudes during the colder glacial periods and expand northwards and up the elevation during warmer interglacial periods. Some species however are capable of adapting to changing environment which allows them to persist in place despite climatic changes. I explored how climatic changes after the last glacial maximum (LGM) effected two species inhabiting the deserts of western North America: one mammal (Chisel-toothed Kangaroo Rat, Dipodomys microps) and one reptile (Desert Horned Lizard, Phrynosoma platyrhinos). I used …

Description Of The Tadpole Of Proceratophrys Renalis (Miranda-Ribeiro, 1920) (Anura: Cycloramphidae), Filipe Augusto C. Do Nascimento, Barnagleison S. Lisboa, Gabriel O. Skuk, Rafael O. De Sá

Biology Faculty Publications

The tadpole of Proceratophrys renalis is described based on specimens from Maceió, State of Alagoas, northeastern Brazil. At stage 35 the body is slightly dorso-ventrally depressed, ovoid in lateral, dorsal, and ventral views. Oral disc is ventral with lateral emarginations, surrounded by a single row of marginal papillae with a large gap on the upper labium. Labial tooth row formula is 2(2)/3(1 ). The analysis of internal oral anatomy revealed two possible characters that readily distinguish P. renalis from P. boiei, supporting the recent resurrection of P. renal is. Comparisons with available descriptions of the larvae for other species in …

Distributions Of Sharks Across A Continental Shelf In The Northern Gulf Of Mexico, J. Marcus Drymon, Sean P. Powers, John Dindo, Brian Dzwonkowski, Terry A. Henwood

University Faculty and Staff Publications

Declines in shark populations have sparked researchers and fishery managers to investigate more prudent approaches to the conservation of these fish. As managers strive to improve data collection for stock assessment, fisheries-independent surveys have expanded to include data-deficient areas such as coastal regions. To that end, a catch series from a nearshore survey off Alabama was combined with data from a concurrent offshore survey with identical methodology to examine the depth use of sharks across the continental shelf (2–366 m). The combined data set contained 22 species of sharks collected from 1995 to 2008: 21 species in the offshore data …

Hydraulic Conductivity, Infiltration, And Runoff From No-Till And Tilled Cropland, Jessica H. Deck

Department of Environmental Engineering: Theses and Other Student Research

Infiltration and runoff are important processes that affect the efficiency of center pivot irrigation systems. No-till planting systems potentially influence the hydraulic properties of soils and the soil surface conditions. The result of long-term use of no-till could be higher infiltration and lower runoff from rainfall and irrigation.

This potential was investigated in Nebraska on two center pivot irrigated sites; Fillmore County and Phelps County, one furrow irrigated site; South Central Agriculture Laboratory (SCAL), and one dryland site; Rogers Farm. Paired treatments were used at each location, one that was no-till planted and one that used two to three operations …

Geological And Ichthyological Investigations Into Palaeodrainage Hypothesis For The Tennessee River, Andrea Karen Persons

Dissertations

The course of the ancestral Tennessee River has been debated in both the geological and biological literature for over 100 years. Several of the proposed courses for the ancestral Tennessee place its course across the state of Mississippi. Geochemical analysis of sedimentary rocks in the Pascagoula River basin supports these hypotheses suggesting that the rocks in the Pascagoula basin were derived from the Highland Rim of Tennessee and northern Alabama, while geochemical analysis of rocks from the Pearl River basin point to deposition from a mixture of sources including the ancestral Mississippi River and perhaps the ancestral Tennessee. To delve …

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2009, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman, Raghavendra Kurada

Status and Trends for Virginia Chesapeake Bay

The period prior to the implementation of the Chesapeake Bay Monitoring Program was characterized by a marked decline in the water quality of the Chesapeake Bay. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality (e.g. USEPA, 1982,1983;Officer et al.,1984; Orth and Moore, 1984). The results of concentrated research efforts in the late 1970s and early 1980s stimulated the …

Time, Temperature And Species Interactions In A Duckweed–Herbivore Mesocosm, Ian Waterman

School of Biological Sciences: Dissertations, Theses, and Student Research

Species interactions within a community are impacted by a variety of abiotic factors. Temperature is known to alter population dynamics such that direct and indirect interactions between populations within a community are affected. Here I investigate the effect of temperature change on species interactions within a duckweed-herbivore mesocosm. Multiple communities were constructed, from a single population of duckweed, to two populations of duckweed consumed by aphids. In the one-predator two-prey web we predicted mutually positive indirect effects between duckweed populations during the first generation of growth. As aphid populations respond numerically to more abundant prey, mutually negative and asymmetric indirect …

Osteology, Natural History Notes, And Phylogenetic Relationships Of The Poorly Known Caribbean Frog Leptodactylus Nesiotus (Anura, Leptodactylidae), María Laura Ponssa, Michael J. Jowers, Rafael O. De Sá

Biology Faculty Publications

The Leptodactylus melanonotus group consists of 15 species, but references to skeletal characters are available for only three species: L. leptodactyloides, L. melanonotus, and L. diedrus. Leptodactylus nesiotus is a member of the melanonotus group known only from the type locality, Bonasse swamp, on the Southwestern peninsula of Trinidad, Trinidad and Tobago. This species has been categorized as vulnerable given its restricted distribution. Herein, we report the adult osteology of L. nesiotus, the skeletal characters are compared with the available data from other Leptodactylus species. A phylogenetic analysis recovers a paraphyletic L. melanonotus group relative to the L. …

A Study Of Corallivores Of Bawe And Chumbe Islands, Zanzibar, Rachael Mallon

Independent Study Project (ISP) Collection

Coral reefs are considered keystone ecosystems due to their socioeconomic, ecological, and educational value. In Zanzibar, Tanzania, reefs provide income and a protein source for large portions of the population. Fish are reliant upon reefs as grounds for feeding, breeding, and nursing. Reefs are related to mangrove and seagrass ecosystems; the three ecosystems are interconnected in their functions of protecting biodiversity of coastal organisms, coastal erosion, and improving water quality. Coral reefs are also subject to degradation by both anthropogenic and natural causes. Predation is one example of natural degradation of coral. Six species of corallivores were studied to compare …