Biodiversity Commons^™

Macrobenthic Communities In The Northern Gulf Of Mexico Hypoxic Zone: Testing The Pearson-Rosenberg Model, Shivakumar Shivarudrappa

Dissertations

The Pearson and Rosenberg (P-R) conceptual model of macrobenthic succession was used to assess the impact of hypoxia (dissolved oxygen [DO] ≤ 2 mg/L) on the macrobenthic community on the continental shelf of northern Gulf of Mexico for the first time. The model uses a stress-response relationship between environmental parameters and the macrobenthic community to determine the ecological condition of the benthic habitat. The ecological significance of dissolved oxygen in a benthic habitat is well understood. In addition, the annual recurrence of bottom-water hypoxia on the Louisiana/Texas shelf during summer months is well documented.

The P-R model illustrates the decreasing …

Urban Agriculture And Ecosystem Services: A Typology And Toolkit For Planners, Kathleen Doherty

Masters Theses

This thesis makes the connection between urban agriculture and a specific suite of ecosystem services and lays out a typology and toolkit for planners to take advantage of these ecosystem services. The services investigated here are: food production, water management, soil health, biodiversity, climate mitigation, and community development benefits. Research from a variety of fields was aggregated and synthesized to prove that urban agriculture can be beneficial for human as well as environmental health.

A set of urban agriculture typologies was generated to illustrate best practices to maximize a particular set of ecosystem services. The typologies are: production farm, stormwater …

Rock Creek Restoration Macroinvertebrate Monitoring Report, Daniel Bedell

Environmental Science and Management Professional Master's Project Reports

Stream restoration is widely used to rebuild habitat for native fisheries, but it is not well understood how current habitat reconstruction practices affect biological diversity. Citizen Science programs have potential to provide supplemental macroinvertebrate data for effectiveness monitoring of reach-scale restoration projects but variability in training, experience and collection methods can make interpretation difficult. The Clackamas Water Environment Services Watershed Health Education Program (WHEP) is an example of a Citizen Science-based program actively collecting biological data from restored streams. The purpose of this project was to use WHEP student-collected data to detect benthic macroinvertebrate community responses to stream restoration practices. …

Is Chir Pine Displacing Banj Oak In The Central Himalaya? Socioeconomic Implications For Local People And The Conservation Of Oak Forest Biodiversity, Ankush Nautiyal

Graduate Theses and Dissertations

Various studies have suggested that chir pine (Pinus roxburghii) is replacing banj oak (Quercus leucotrichophora) in the Central Himalaya. Five sites with three different types of forests (banj oak, chir pine and mixed oak-pine) were sampled to compare the diversity of their vegetation and to assess the impact of this ongoing conversion on biodiversity. Soil samples collected from oak and pine forests were analyzed and compared. In addition, dendrochronology was used to obtain age estimates of chir pine and to understand the growth response of this species to precipitation. Also, samples of ectomycorrhizal fungi were collected in the form of …

Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a critical need for detailed surveys of lakes covering large spatial (>100 km²) and temporal scales (decades) to determine if there is an increase in the magnitude and frequency of phytoplankton blooms. Remote sensing was used to: (1) develop a regression model that relates chlorophyll a (chl-a) as a proxy of lake phytoplankton biomass to Landsat TM and ETM+ optical reflectance (r²=0.85, p

Investigating Seed Dispersal Distances And Long Distance Dispersal Mechanisms Of The Invasive Plant, Alliaria Petiolata, Christopher Loebach

Theses and Dissertations

Alliaria petiolata, an herbaceous plant, has aggressively invaded North American woodlands. It has been extensively studied to understand why it is a successful invader, but certain aspects of its biology have been understudied such as seed dispersal distances and long distance dispersal mechanisms (LDDM). My thesis experimentally measured A. petiolata seed dispersal distances and determined if epizoochory (external animal transport) is a LDDM. To measure dispersal distances, seed traps were placed around three A. petiolata seed point sources to capture dispersed seeds at increasing distances away from the point sources. Eight mathematical functions that describe dispersal distances were fitted to …

Examining The Impacts Of Valley Fills In Stream Ecosystems On Amphibian And Aquatic Insect Communities In Southeastern Kentucky, John Clayton Bourne

Online Theses and Dissertations

Chapter 1. Abstract: Biodiversity is not evenly distributed, and understanding factors that determine spatial patterns of species diversity remains a key question in ecology. Because of their relatively high abundance and complex life cycles, stream salamanders and aquatic insects are important trophic links and serve a critical role in transferring energy. Despite this importance little research has examined their community structure simultaneously in aquatic ecosystems. The primary objective of this research was to determine the structure of these communities across natural areas of southeastern Kentucky and understand what factors impact their abundances and distributions. To address this, we sampled eight …

Effects Of Prescribed Fire On Upland Plant Biodiversity And Abundance In Northeast Florida, Peter D. Maholland

UNF Graduate Theses and Dissertations

Terrestrial ecosystems in the southeastern United States have evolved with fire as a common disturbance and as a result many natural communities require the presence of fire to persist over time. Human development precludes natural fires from occurring within these communities; however, prescribed fire is considered to be a critical tool in the effort to restore fire-dependent ecosystems after decades of fire exclusion. Direct effects of fire on individual floral and faunal species as well as benefits to biodiversity at the landscape (gamma diversity) level have largely been supported in previous research. However, information on the effects of natural and …

An Assessment Of The Role Of Roads In Population Demography And Genetic Structuring In Two Species Of Lizards In The Northern Chihuahuan Desert, Kevin Floyd

Open Access Theses & Dissertations

Roads can fragment habitat and increase mortality rates of wildlife, potentially reducing population sizes and gene flow, which in turn can reduce genetic diversity through genetic drift. Although negative road impacts have been found in a variety of taxa, not all species are impacted. For instance, species that move less and rarely encounter roads and those that avoid the roads are predicted to not be negatively affected. Yet tests of these predictions are uncommon, especially for reptiles and particularly lizards. Side-blotched lizards (Uta stansburiana) are small sit-and-wait predators, while the larger marbled whiptails (Aspidoscelis marmorata) are active foragers. Their responses …

Mercury Reduces Avian Reproductive Success Through Direct Embryotoxicity Rather Than Altered Parental Behavior, Stephanie Yen Chin

Dissertations, Theses, and Masters Projects

No abstract provided.

A Gis Assessment Of Ecoregion Representation In Chile's Existing And Proposed Integrated Network Of Protected Areas, Jessica Schutz

Graduate Student Theses, Dissertations, & Professional Papers

Chile's state designated protected areas are reported to show representation bias and to be unable to meet conservation goals. Private protected areas are considered an important tool to resolve these issues, which has led to support for increasing the role of private protected areas in Chile and creating an integrated public-private protected area network. But the validity of the capacity of private protected areas to fix Chile's state protected area network bias, and the advantage of creating an integrated protected area network, have not been assessed. This study uses the most recent data on Chile's state, private, and international protected …