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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 …

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 …

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 …

Elemental Challenges: Environmental Troubles Beyond The Limits Of Democracy, Brad Mapes-Martins

Open Access Dissertations

From an examination of how environmental issues reshape politics, this inquiry focuses on the theoretical grounds of deliberative democratic theory to ask whether such a vision offers the best means of resolving environmental problems. Arguing that the very terms in which environmental politics have been defined retain features better suited to previous historical circumstances, the analysis proceeds from features typical of environmental problems to a more context-specific assessment of the role for democratic participation. Engaging the works of Jürgen Habermas, the author details the way in which deliberative democratic theory is indebted to a concept of communicative action that defines …

Growth Of Atlantic Salmon (Salmo Salar) In Freshwater, Douglas Bradlee Sigourney

Open Access Dissertations

Growth plays a key role in regulating ecological and population dynamics. Life history characteristics such as age at maturity, fecundity and age and size at migration are tightly linked to growth rate. In addition, size can often determine survival and individual breeding success. To fully understand the process of growth it is important to understand the mechanisms that drive growth rates. In Atlantic salmon, growth is critical in determining life history pathways. Models to estimate growth could be useful in the broader context of predicting population dynamics. In this dissertation I investigate the growth process in juvenile Atlantic salmon (Salmo …

New England Terrestrial Settlement In A Submerged Context: Moving Pre-Contact Archaeology Into The Twenty First Century, Kerry J. Lynch

Open Access Dissertations

Human occupation of the New England region of North America during the early Holocene has long been established archaeologically. However, the data exists almost solely from terrestrial sites. Vast portions of aerial land once available to early occupants of the area for resource procurement and living surfaces are now submerged. Underwater pre-Contact resources embedded in these submerged landforms will undeniably contribute to a holistic understanding of New England's cultural history. Examination of current archaeological procedures reveal that the archaeological standards, practices, and theories commonly employed in terrestrial archaeology are largely not being extended past the coastline into the underwater environment. …

Greenspace Conservation Planning Framework For Urban Regions Based On A Forest Bird-Habitat Relationship Study And The Resilience Thinking, Sadahisa Kato

Open Access Dissertations

The research involves first conducting a "case study" of ecological data and applying the results, together with the resilience concept, to the development of a greenspace conservation planning framework for urban regions. The first part of the research investigates the relationship between forest bird abundance and the surrounding landscape characteristics, especially, forest area and its spatial configuration in urban regions at multiple scales. The results are similar for simple and multiple regression analyses across three scales. The percentage of forest cover in a landscape is positively correlated with bird abundance with some thresholds. Overall, the percentage of forest cover in …

Ciliate Biodiversity And Phylogenetic Reconstruction Assessed By Multiple Molecular Markers, Micah Dunthorn

Open Access Dissertations

Ciliates provide a powerful system within microbial eukaryotes in which molecular genealogies can be compared to detailed morphological taxonomies. Two groups with such detailed taxonomies are the Colpodea and the Halteriidae. There are about 200 described Colpodea species that are found primarily in terrestrial habitats. In Chapters 1 and 2, taxon sampling is increased to include exemplars from all major subclades using nuclear small subunit rDNA (nSSU-rDNA) sequencing. Much of the morphological taxonomy is supported, but extensive non-monophyly is found throughout. The conflict between some nodes of the nSSU-rDNA genealogy and morphology-based taxonomy suggests the need for additional molecular marker. …

Distribution And Diversity Of Planktonic Ciliates: Patterns And Processes, Mary Doherty

Open Access Dissertations

The nature and extent of microbial biodiversity remain controversial with persistent debates over patterns of distributions (i.e. cosmopolitanism vs. endemism) and the processes that structure these patterns (neutrality vs. selection). We used culture-independent approaches to address these issues focusing on two groups of ciliates, the Oligotrichia (Spirotrichea) and Choreotrichea (Spirotrichea). To assess the diversity of these ciliates, we designed primers specific to SSU rDNA of ciliates within these clades, and investigated (1) geographic and temporal distributions along three coastal sites in the Northwest Atlantic; (2) the relationship between ciliate communities in the benthos and the plankton along the New England …

An Assessment Of Natural Resources Management Conflicts In The Working Landscapes Of Mediterranean Turkey (Turkiye): Koprulu Kanyon National Park, Nedim Kemer

Open Access Dissertations

Environmental conservation and natural resources management are critical global issues of the 21st century. The management of protected public lands emerges as a challenge particularly in developing countries because of the biophysical and socio-cultural importance of these lands. These lands are often referred to as 'working landscapes' where the natural systems and the collective actions of local residents have shaped one another in well-balanced interactions for generations. The working landscapes of the Köprülü Kanyon National Park (KKNP) in Turkey have provided the case study for this dissertation. Eleven villages exist within the park with a total of approximately 7,100 residents. …