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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An evaluation of coastal zone management

Guerinoni, Stephen C., n/a January 1989 (has links)
The coastal zone is a valuable resource which provides a diversity of benefits. The difficulties facing the coastal zone tend to fall into three categories: (1) Pressure and conflict on resources. The beach residence value, an indicator of land use pressure, implies that, of the Australian states, New South Wales' coastal zone is under the greatest pressure. Associated with population is development pressure. Many forms of development are not compatible, hence conflicts of interest can arise. (2) The dynamic nature of the coast. That is, the physical and biological aspects of the coastal zone are in a state of flux. The dynamics make predictions for management controversial. (3) Organisational problems. The lack of direction, lack of coordination and fragmentation of management leads to ad hoc management of this valuable resource. This evaluation identified and confirmed the relevance of coastal issues which led to the enactment of the Coastal Protection Act, 1979. The coastal issues investigated were: coastal erosion and development; coastal erosion and protection works; coastal land degradation; degradation of coastal habitats, fish and wildlife resources; recreation opportunities; pollution; and increasing population pressure and competition betweeen alternative uses. The administrative arrangements for management of the issues were investigated. A broad range of coastal issues were evaluated using a mix of indicators with standards of comparison to measure progress. Management tools, policies and strategies used to address the issues were investigated. Finally prescriptions to further address the issues were made as was how to implement the prescriptions. The evaluation noted: increasing coastal population and development pressure; numerous examples of conflicts of interest; complex and often bewildering administrative arrangements for coastal zone management; widely varying levels of performance by agencies; and a lack of direction and co-ordination from State authorities. The principal conclusion was that strategic planning needed to be undertaken through a lead coastal agency. The lead agency should clarify and improve direction, co-ordination and co-operation in coastal management. This should improve the effectiveness of management and reduce the incidence and duration of conflict among the different and competing coastal values. This evaluation of the effectiveness of coastal management, at a State level, should not only assist New South Wales but also other States in the management of this valuable resource.
2

Plant communities and succession in Oregon coastal salt marshes /

Jefferson, Carol A. January 1974 (has links)
Thesis (Ph. D.)--Oregon State University, 1975. / Typescript (photocopy). Includes bibliographical references. Also available online.
3

The role of contaminants in altering the coastal environment of Samoa /

Suluvale, Eletise Taauta. January 1997 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Geography & Environmental Studies, 1999? / Errata list behind front end-paper. Bibliography: leaves 335-359.
4

Raster based coastal marsh classification within the Galveston Bay ecosystem, Texas

Edwards, Aron Shaun 15 May 2009 (has links)
A mapping study using remote sensing software called ENVI was conducted utilizing four software algorithms to investigate whether these techniques could accurately classify habitat types and vegetation communities along West Bay of the Galveston Bay Ecosystem from color infra-red (CIR) imagery. The algorithms were used in a small-scale study to investigate which of these techniques could most accurately distinguish habitat types and vegetation communities from the imagery at a site specific location. The most accurate algorithm of the four was used in a large-scale classification study in which entire images were classified utilizing the same data from the small-scale study. Regions of interest (ROIs) were used within ENVI to specify areas of interest within each image that was classified. The locations of ROIs were recorded using a GPS prior to classification, then each was added into ENVI as data points, and each ROI polygon was digitized according to its respective pixel color. Once all of the ROI polygons were completed, each software algorithm was employed. After classification, each habitat type and vegetation community was ground-truthed in order to verify the accuracy of the algorithms. The position points were added as ground truth points within ENVI and an accuracy matrix was assessed. The technique with the greatest averaged accuracy within the smallscale study was selected for the large-scale study. The ROIs and ground truth points used in the smallscale study were used again in the large-scale study. The small-scale study concluded that the Parallelepiped algorithm produced significantly less accurate classifications than the other three. Although the Mahalanobis algorithm was not significantly different from the other two algorithms, it yielded the highest overall average accuracy and was used in the large-scale study. In both the small-scale and large-scale studies there was no significant difference in the two different years of aerial imagery and there were no significant differences in accuracy for locations. None of the software algorithms were accurate at classifying habitat types and vegetation communities using the imagery. The accuracy for the Mahalanobis algorithm was less than 60%. Inaccuracies were largely due to overlapping spectral signatures among habitat types and vegetation communities.
5

A review of habitat loss and coastal development of Hong Kong with special reference to Lantau Island

Tang, Wai-wah. January 2009 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 141-161).
6

Beach budget analysis and shingle transport dynamics in West Dorset

Bray, Malcolm John January 1996 (has links)
Comprehensive sediment budgets are compiled for a series of pocket shingle beaches in West Dorset backed by massive soft cliffs that degrade in a rapid and complex manner. Studies involve the identification and quantification of sediment (primarily shingle) inputs, transfers, storage and outputs within terrestrial and marine subsystem components. Results are unified within budget and flow models and applied to tackle questions of coastal evolution and management. Research involved mapping and sampling of the ground forming materials in terms of their beach forming potential. Cliff landsliding and recession are analysed using comparisons of historical maps, aerial photos and documentary evidence. A method of quantifying the release, throughput and supply to the beaches of various sediment grades from the eroding cliffs is presented. The volumes and types of sediment at the beach and in the inshore zone are investigated by various profile, intertidal, and offshore surveys. Detailed sampling and sediment analysis of the beaches is undertaken to elucidate beach drift and for attrition assessments through comparisons with cliff inputs. Shingle tracing experiments using aluminium tracers are conducted to study transport and sorting at two contrasting sites over a full spectrum of wave energy conditions. Validated littoral drift volumes and original wave power relationships are developed. Information is compiled to produce budget models for the main beaches. Complex long established links are demonstrated between eroding cliff sources and the shingle beaches that they supply. Chesil Beach is identified as the ultimate shingle sink suggesting that it is not entirely a product of the Holocene transgression as often envisioned, but a component of a Lyme Bay process system and open periodically to inputs of shingle from the west. Adverse impacts arising from various human interventions are highlighted using the models.
7

Influence of landscape-scale variables on the age and growth of coastal cutthroat trout Oncorhynchus clarkii clarkii in headwater streams /

Rehe, William G. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves [86-108]). Also available on the World Wide Web.
8

Habitat use, movement, and life history variation of coastal cutthroat trout, Oncorhynchus clarkii clarkii, in the Salmon River estuary, Oregon /

Krentz, Lisa K. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
9

Exploring coastal spaces : towards linking social and ecological systems.

Colenbrander, Darryl. January 2009 (has links)
Coastal zone definitions are typically guided by the presence of absolute demarcations. As a result, the coastal zone becomes confined to, and identified as, an absolute space. This research challenges the ‘fixed’ nature of the coastal zone and suggests that there are a wide range of relational spaces that overlap and engage with each other to form the coastal space. These spaces and their sphere of influence extend beyond the ‘boundaries’ of what is legally defined as the coastal zone. Multiple coastal spaces have been identified based upon coastal stakeholder perceptions of what is relevant to the management of the coastal zone. Although there is a place for the absolute manner in which coastal zones are defined, definitions founded on absolute parameters tend not only to create a fixed abstract space, but they also naturalize a geographical construct to an unhelpful scale in terms of the functioning of coastal socio-economic and environmental systems. The absolute manner in which the coastal zone is defined and the reduced scale at which such a definition and the associated legislation is directed, severs and discounts, both temporarily and spatially, the influences of relational spaces that function at broader scales. The complication arises when the influences of such spaces are enmeshed within and beyond that legally defined coastal space. The legal definition and the associated legislation, in essence, attempts to address and solve issues occurring within the legal space, but disregards causative mechanisms that may lie outside of that legal space. This study suggests that a broader scaled and more holistic approach to defining the coastal zone, namely a system characterized by flows of interrelated spaces, will enable higher levels of sustainability to be achieved. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2009.
10

Past, Present and Future: Morphology and Dynamics of Rivermouth Lagoons in Westland, New Zealand

Kain, Claire Louise January 2009 (has links)
Coastal wetlands and rivermouth lagoons are dynamic systems, which respond rapidly to sea-level, tectonic, meteorological, anthropogenic and other synergistic drivers. This research used a multi-disciplinary approach to investigate two representative West Coast lagoon systems (Totara Lagoon and the Shearer Swamp-Waikoriri Lagoon Complex) in order to document their present-day geomorphology and determine the development and processes acting on these systems over historical time. This information was then used to predict their future under varying climate, development and management pressures. In addition to adding to the West Coast knowledge base, the findings of this research are applicable to similar systems elsewhere in New Zealand and internationally. This investigation used a multidisciplinary approach to investigate the dynamics, structure, development and active processes in the two study systems. Techniques to document current hydrology and topography included hydrological records of water level, temperature and conductivity, and Global Navigation Satellite Surveys (GNSS). Outlet dynamics over a decadal scale were investigated through temporal aerial photograph analysis, and sediment core analyses showed changes occurring over longer timescales. Significant differences in morphology and dynamics were observed between Totara Lagoon and Waikoriri Lagoon, with the former being much larger, more stable, and less dynamic in terms of dune morphology and outlet migratory patterns. Hydrologically, Totara Lagoon is currently in an estuarine phase, and experiences significant tidal inflows, which demonstrates the connectivity between definitions of coastal lagoons and estuaries. Waikoriri Lagoon is freshwater, and can be described as a hapua-type system, but exhibits very different river flow and barrier composition to East Coast examples. Sediment core analyses from Shearer Swamp and northern Totara Lagoon showed little change over a decadal to centennial scale, but evidence of a change in margin dynamics in response to farming and stabilisation of adjacent dune ridges was observed in Shearer Swamp. Results suggest landward migration of the southern end of Totara Lagoon occurred over this timeframe. The future of these systems depends on the interaction between climate and anthropogenic (including management) factors. A conceptual model of process and response suggests three possible resultant scenarios: lagoon loss, natural lagoon, or artificially modified lagoon. A significant finding of this research is the recognition that some systems exist on a continuum between a hapua and an estuary, switching hydrological states through time while maintaining consistent morphology. In addition, the importance of barrier permeability in hapua formation is highlighted, and the term ‘sandy hapua’ introduced to distinguish these low-flow systems with low barrier permeability from the typical mixed sand and gravel examples documented on the East Coast. These findings enhance scientific understanding of rivermouth lagoon systems, and demonstrate the wide spectrum of conditions under which they may form. This process-based understanding is important from a coastal management perspective as concerns of human induced climate change and accelerated sea level rise grow.

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