Digital Commons Network^™

Landscape Predictors Of Current And Future Distribution Of Mountain Gorillas (Gorilla Beringei Beringei) In Bwindi Impenetrable National Park, Uganda, Dennis Babaasa

Doctoral Dissertations

Context: The impacts of ecological, anthropogenic and future climate change on the distribution of wild mountain gorillas (Gorilla beringei beringei) are of ongoing concern. Knowing the factors that determine gorilla habitat suitability now and in future is essential for conservation planning. The mountain gorilla is recognized by IUCN Red Data Book as critically endangered and a great tourist attraction. However, the factors that impact on their spatial use of Bwindi are poorly understood. Aims: I aimed at determining the major factors that determine gorilla distribution, predict the wild gorilla habitat suitability and establish the vulnerability index …

Epidemiological Evidence Of Childhood Leukaemia Around Nuclear Power Plants, Marek K Janiak

Dose-Response: An International Journal

No abstract provided.

Honesty And Carotenoids In A Pigmented Female Fish, Alexandria Christine Brown

Doctoral Dissertations

The carotenoid tradeoff hypothesis states that diet-derived carotenoids are tradedoff among competing physiological demands, but this statement is rarely tested in ornamented females. The following dissertation tests the carotenoid tradeoff hypothesis in reverse sexually dimorphic convict cichlids (Amantitlania siquia) using carotenoidsupplemented diet treatments and a field-based study of carotenoid intake. Spectral, microscopic, and chemical analysis determined how females allocated the pigments to tissues and how those decisions affected their ventral patch coloration. The results presented in the current study show that carotenoids enhance offspring growth and survival, lower oxidative stress, and reduce the time to clear a parasite. The two …

Examining Spatial Pattern And Interaction Of Human-Induced Vegetation Impacts At Cadillac Moutain In Acadia National Park, Min Kook Kim, David A. Graefe, John J. Daigle

National Environment and Recreation Research Symposium

No abstract provided.

An Assessment Of Environmental Dna As A Tool To Detect Fish Species In Headwater Streams, Stephen F. Jane

Masters Theses 1911 - February 2014

Recent years have seen an explosion of interest in the use of freely available DNA present in aquatic systems, otherwise known as environmental DNA (eDNA), as a tool for monitoring aquatic organisms. However, much remains unknown about the behavior of eDNA over a range of environmental conditions. This is particularly true in high gradient headwater streams, which have received less attention than other types of water bodies. In the summer of 2011, a headwater stream system with well established species distributions was sampled using eDNA techniques. Though species were detected where known to be present, detections also occurred where traditional …

Effects Of Invasive Winter Moth Defoliation On Tree Radial Growth In Eastern Massachusetts, Usa, Michael J. Simmons, Thomas D. Lee, Mark J. Ducey, Joseph S. Elkinton, George H. Boettner, Kevin J. Dodds

Environmental Conservation Faculty Publication Series

Winter moth, Operophtera brumata L. (Lepidoptera: Geometridae), has been defoliating hardwood trees in eastern Massachusetts since the 1990s. Native to Europe, winter moth has also been detected in Rhode Island, Connecticut, eastern Long Island (NY), New Hampshire, and Maine. Individual tree impacts of winter moth defoliation in New England are currently unknown. Using dendroecological techniques, this study related annual radial growth of individual host (Quercus spp. and Acer spp.) trees to detailed defoliation estimates. Winter moth defoliation was associated with up to a 47% reduction in annual radial growth of Quercus trees. Latewood production of Quercus was reduced by up …

Association Of Hypertension Mortality Rates With Geographic Concentrations Of Chiropractors And Medical Doctors In The U.S., 2008, John Hart

Dose-Response: An International Journal

As concentration (dose) of health care providers increases, health outcomes (responses) are expected to be favorable (e.g., decrease in mortality rates). Accordingly, this data- driven, ecological study compares hypertension mortality rates in the U.S. by state to concentrations of doctors of chiropractic (DC) and medical doctors (MD). DC and MD concentrations (per 10,000 population) were separately compared to 2008 hypertension death rates using Spearman correlation analysis and linear regression (where appropriate). DC concentrations revealed a stronger beneficial association with hypertension death rates (r = -0.430, p = 0.0020) compared to MD concentrations (r = -0.029 with an observed outlier, and …

Social Vulnerability, Green Infrastructure, Urbanization And Climate Change-Induced Flooding: A Risk Assessment For The Charles River Watershed, Massachusetts, Usa, Chingwen Cheng

Open Access Dissertations

Climate change is projected to increase the intensity and frequency of storm events that would increase flooding hazards. Urbanization associated with land use and land cover change has altered hydrological cycles by increasing stormwater runoff, reducing baseflow and increasing flooding hazards. Combined urbanization and climate change impacts on long-term riparian flooding during future growth are likely to affect more socially vulnerable populations. Growth strategies and green infrastructure are critical planning interventions for minimizing urbanization impacts and mitigating flooding hazards. Within the social-ecological systems planning framework, this empirical research evaluated the effects of planning interventions (infill development and stormwater detention) through …

Resilient Environmental Governance: Protecting Changing Ecosystems Through Multilevel Governance, Casey Stevens

Open Access Dissertations

International governance is increasingly defined by multilevel governance; with short-term projects, transnational cooperation between different groups, and unclear institutional space. In this situation, a key issue is the resilience of governance arrangements or the ability of governance arrangements to respond to political and ecological shocks to the system. Using international biodiversity governance, this study explores the question: What social and political processes produce resilient governance?

This study argues that the key to understanding resilient governance is the network structure within and outside of the governance arrangement. Modular network structures are able to generate ideas from multiple sources, able to solve …

Land Elevation And Cancer Mortality In U.S. Cities And Counties Using Median Elevations Derived From Geographic Information Systems, John Hart

Dose-Response: An International Journal

There are a number of variables that are correlated with land elevation. Land elevation, and in particular, its surrogate variables such as natural background radiation, can be studied in relation to cancer rates. The present ecological study focuses on three such variables correlated with land elevation: natural background radiation (NBR), oxygen concentration (OC), and barometric pressure (BP). In addition, the study uses a novel approach for determining median land elevation values from which the surrogated variables are estimated. Inverse correlations were observed for NBR while direct correlations were found for OC and BP suggesting the presence of a protective effect …

Social Enterprise In Latin America: Dimensions Of Collaboration Among Social Entrepreneurs, Kevin Moforte Madsen

School of Public Policy Capstones

No abstract provided.

Seasonal Variation Of Suicide Rates Within Alaska: Associations Of Age And Sex, Jonviea Chamberlain

Masters Theses 1911 - February 2014

Background: Suicide rates among Alaska Natives in rural Alaska are almost 16 times higher than the national average. Some studies in northern latitudes have shown seasonal variation among suicide rates, with differences in patterns by age and sex, reasons for this variation and contributing factors are unclear. We modeled our hypotheses based on the assumption that vitamin D deficiency influences seasonal variation of suicide. We assessed the relationship between age, sex and seasonal variation of suicidal behavior in a rural region of Alaska. Methods: We utilized data from 804 individuals who exhibited lethal and nonlethal suicidal behavior (1990-2009). Information on …

The Lovely And The Wild: Considering Naumkeag, Carol Waag

Masters Theses 1911 - February 2014

This paper investigates Fletcher Steele’s ideas about nature, and the fitness of gardens, in order to guide and support a reinvigoration of Naumkeag. Its aim is to highlight the protection of ecological resources while preserving aesthetic and historic integrity. This topic is particularly timely as The Trustees of Reservations are in the process of completing an extensive and unprecedented restoration plan, which will be carried out over the next five years. The Trustees have a long history of historic preservation and ecological conservation. This paper explores how these two aspects of their work can be integrated at Naumkeag, with particular …

Vernal Pool Vegetation And Soil Patterns Along Hydrologic Gradients In Western Massachusetts, Kasie Collins

Masters Theses 1911 - February 2014

This study looks at relationships along the hydrologic gradient between and within six pools; including the vegetation community, soil characteristics and hydrology. Pool conditions were monitored weekly throughout the 2011 and 2012 growing seasons. Each pool was equipped with permanent platinum-tipped redox probes to quantify the severity and duration of soil reduction. We described and analyzed 12 soil profiles in each pool, distributed in summit/upland, basin, and rim/transition positions as defined by the high water line. The pools were systematically surveyed for understory vegetation during the 2012 growing season.

Vegetation patterns varied between study areas. No clear pattern of unique …

Special Issue Introduction, Bobby R Scott, Ludwik Dobrzy´Nski

Dose-Response: An International Journal

No abstract provided.

The Cancer Mortality In High Natural Radiation Areas In Poland, Krzysztof Wojciech Fornalski, Ludwik Dobrzyn´Ski

Dose-Response: An International Journal

The cancer mortality ratios (CMRs) in Poland in high and low level radiation areas were analyzed based on information from national cancer registry. Presented ecological study concerned six regions, extending from the largest administration areas (a group of voivodeships), to the smallest regions (single counties). The data show that the relative risk of cancer deaths is lower in the higher radiation level areas. The decrease by 1.17%/mSv/year (p = 0.02) of all cancer deaths and by 0.82%/mSv/year (p = 0.2) of lung cancers only are observed.

Cancer Mortality, State Mean Elevations, And Other Selected Predictors, John Hart, Seunggeun Hyun

Dose-Response: An International Journal

This ecological inquiry compares cancer mortality rates in the U.S. to the predictor of natural background radiation (via land elevation means) along with eight other predictors thought to be associated with cancer mortality. Age-adjusted cancer mortality in 2006 was compared to the predictors of mean land elevation, percent of smokers, educational attainment, percent of population without health insurance, income, obesity, health perception, physical activity, and diet. Among the six predictors considered appropriate for multiple linear regression, three were found to be statistically significant; from strongest to weakest, these three were: smoking, land elevation, and educational attainment. The predictors of smoking …

An Investigation Of Human-Error Rates In Wildlife Photographic Identification; Implications For The Use Of Citizen Scientists, Megan Chesser

Masters Theses 1911 - February 2014

Rapid technological advancements in digital cameras and widespread public access to the internet have inspired many researchers to consider alternative methods for collecting, analyzing, and distributing scientific data. Two emerging fields of study that have capitalized on these developments are “citizen science” and photo-id in wildlife capture-mark-recapture (CMR) studies. Both approaches offer unprecedented flexibility and potential for acquiring previously inconceivable datasets, yet both remain dependent on data collection by human observers. The absence of rigorous assessment of observer error rates causes many scientists to resist citizen science altogether or to fail to incorporate citizen-collected data into ecological analyses. This same …

Risk Considerations Related To Environmental Arsenic Exposure: Drinking Water Ingestion Versus Dietary Intake Or Soil Exposure, Christopher M. Teaf, Douglas Covert

Proceedings of the Annual International Conference on Soils, Sediments, Water and Energy

The February 2010 release of the Draft Toxicological Review of Inorganic Arsenic by the U.S. Environmental Protection Agency provoked discussion of a potential significant downward revision of the arsenic cancer slope factor (CSF), which would be applicable to many oral exposure evaluations. Given the extreme variability in soil cleanup guidelines that are in use throughout the United States and internationally for arsenic, it may be appropriate to more seriously consider bifurcating the manner in which arsenic is evaluated in environmental media. In much the same fashion by which manganese and cadmium presently are evaluated from a risk perspective, arsenic may …

Residential Radon Appears To Prevent Lung Cancer, Bobby R Scott

Dose-Response: An International Journal

Residential radon has been found to be associated with lung cancer in epidemiological/ ecological studies and the researchers have inappropriately concluded that residential radon causes lung cancer. Their conclusion relates to the linear-no-threshold (LNT) hypothesisbased, risk-assessment paradigm; however, the LNT hypothesis has been invalidated in numerous studies. It is shown in this paper that our hormetic relative risk (HRR) model is consistent with lung cancer data where detailed measurements of radon in each home were carried out. Based on the HRR model, low-level radon radioactive progeny is credited for activated natural protection (ANP) against lung cancer including smoking-related lung cancer. …

Dose-Response, Vol 9, No 4, Table Of Contents

Dose-Response: An International Journal

No abstract provided.

On Ecological Studies: A Short Communication, John Hart

Dose-Response: An International Journal

The typical objective of research is to try and identify cause-and-effect relationships. As with any research design, there are strengths and weaknesses involved in trying to achieve this objective. Some study designs are stronger than others in attempting to establish cause-and-effect associations. The task of establishing cause-and-effect relationships is challenging (Hill, 1965) and any study that does not include experimentation, that is by manipulating a variable’s exposure, is inhibited from drawing causal inferences (Heath, 1995). Similarly, statistical significance is also based on probability rather than certainty. This article focuses on a particular research design, namely, the ecological study, and attempts …

Deadly Radon In Montana?, John Hart

Dose-Response: An International Journal

No abstract provided.

Cancer Mortality For A Single Race In Low Versus High Elevation Counties In The U.S., John Hart

Dose-Response: An International Journal

A previous study compared cancer mortality in the six lowest versus six highest elevations in the U.S. for all races. This study looks at a single race since death rates tend to vary by race. In this ecological study, cancer mortality rates were compared between low and high states for a race that had sufficient number of counties reporting mortality data, that is, the white race. The average cancer mortality rate for low elevation counties was 73.47 + 18.35 compared to 53.90 + 13.76 for high elevation counties, a difference that was statistically significant (p < 0.0001), with a very large effect size (of 1.2). Higher elevation counties showed less cancer mortality rates for a single race compared to lower elevation counties, suggesting the presence of radiation hormesis. Further rigorous research is indicated to verify or refute these findings.

Lung Cancer In Oregon, John Hart

Dose-Response: An International Journal

Factors thought to be related to lung cancer include smoking, radon, and educational attainment. These factors were analyzed in the present ecological study for Oregon with correlation and linear regression statistics. A moderate, inverse, and statistically significant correlation was found with educational attainment while surprisingly, negligible and statistically insignificant correlations were found with smoking and radon. More rigorous research such as case-control study designs, are indicated to verify or refute these findings.

Deadly Radon In Montana?, Jerome S Puskin

Dose-Response: An International Journal

No abstract provided.

The Conservation Value Of Residential Landscapes For Native Bird Communities: Patterns, Processes, And Management Implications, Susannah Beth Lerman

Open Access Dissertations

Urbanization, as it transforms natural biotic systems into human-dominated landscapes, is recognized as one of the greatest threats to biodiversity throughout the world. Furthermore, urban dwellers are becoming increasingly disconnected with the natural world. Here I investigate whether residential landscape designs that mimic the natural environment can provide habitat for native birds. First I uncover some of the patterns of bird distribution in residential yards by incorporating habitat features, urbanization measurements and socioeconomic factors with bird monitoring data into a multivariate analysis. The results indicate that native birds associate with neighborhoods with native plants and shrubs, neighborhoods closer to desert …

Deadly Radon In Montana? A Brief Note, John Hart

Dose-Response: An International Journal

No abstract provided.

Deadly Radon In Montana? A Rebuttal To Dr. Larsson, John Hart

Dose-Response: An International Journal

No abstract provided.

Developing An Efficient Cover Cropping System For Maximum Nitrogen Recovery In Massachusetts, Ali Farsad

Open Access Dissertations

Time of planting plays a critical role in nitrogen (N) uptake by rye cover crop (CC). Even a few days of delay in planting can severely decrease CC performance. Evaluating the amount of N accumulation related to time of planting is critical to the farmer who has to optimize the winter rye planting date based on completion of corn harvest, suitable weather conditions and time availability for fall manure application. Winter rye cover crop was planted at 6 planting dates in fall from mid August to early October at weekly intervals from 2004 to 2009.

The results suggest that delay …