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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

Exploration of MARXAN for utility in marine protected area zoning

Loos, Sarah Amber 01 May 2006 (has links)
There is a lack of tools for zoning marine protected areas (MPAs). MARXAN is a popular tool for MPA siting, and this thesis explores its use for zoning. MPA managers and zoning practitioners were interviewed in order to determine the requirements of zoning. This, combined with a literature review, informed the testing of several MARXAN settings. This testing was necessary due to poor existing documentation and the uncertainty associated with many settings. Finally, different methods for creating and combining zones were also developed. Due to the complexity of MARXAN it is not possible to develop specific guidelines for many of the settings tested in this research. However, general trends for several settings were determined, and applied within the context of MPA zoning. Preliminary zones were developed and combined using MARXAN’s summed solution output, the results of which are ready for zone refinement with stakeholders and MPA planners.
2

Using Marxan and Marxan with Zones to support marine planning

Peckett, Frances January 2015 (has links)
With the growth in human pressures on the marine environment and the increase in competition for space and resources there has been recognition by many governments of the need to use the marine environment sustainably and allow for its acceptable allocation for each sector. The aim of this thesis is to evaluate the use of Marxan and Marxan with Zones as practical tools to enable the production of marine plans that integrate environmental and socioeconomic data and to suggest best practice in the types of data used. In this thesis three key aspects of data type and integration were identified and evaluated. The resolution and complexity of data required to protected marine biodiversity was assessed. The effects of using different substrate data resolution on the selection of sites to protect a range of biotopes using Marxan are determined. The nature of the data used in marine planning has significant implications for the protection of marine biodiversity. Using less complex data, of any resolution, did not adequately protect marine biodiversity. There is a need to determine what is an acceptable allocation of marine resource to each sector. Two case study areas were used to determine how to integrate conservation and socioeconomic data and objectives in a marine plan. Objectives for all the sectors could not be met completely in a single marine plan and each sector had to compromise. This research highlighted the potential compromises required and indicates that if marine heritage and biodiversity are to be protected each sector will have to change the impact it has on the marine environment. Currently marine conservation assumes that all data on habitats and species presented for use in marine planning are equal, in accuracy, precision and value. This is not always the case, with data based on a wide range of sources including routine government monitoring, specific innovative research and stakeholder based data gathering. A case study area was used to evaluate the impacts of using confidence levels in habitat data on marine biodiversity. It was found that data outputs that best protected marine biodiversity used data over 20% and over 30% confidence. With the data currently available for the UK marine environment it is not possible to be confident that a representative MPA network can be created. Together these studies contribute key recommendations for best practice in marine planning and demonstrate that the use of spatial decision support tools (Marxan and Marxan with Zones) are essential for the integration of data in marine planning, to assess how using different types of data will impact marine planning and marine biodiversity protection and to explore implications of different management actions.
3

Prioritizing Areas for Habitat Conservation in the Face of Climate and Land-Use Change

Robillard, Cassandra January 2016 (has links)
The selection of sites for biodiversity conservation is best done if it anticipates future challenges and efficiently accomplishes targets, given limited funding for such efforts. The first chapter of this thesis discusses how conservation practitioners might manage and enhance long-term survival for species whose ranges must shift as climate changes, across regions that present significant mobility barriers. I describe recommendations highlighting connectivity, refugia from climate change, adaptation, and restoration within agricultural landscapes in North America, but these recommendations are transferable elsewhere. The second chapter examines patterns of change in agricultural intensity and land price within Canada’s species-rich farmland between 1986 and 2011, and creates sequential cost-efficient plans to conserve resident species-at-risk within that time period, to determine how environmental and cost changes erode the efficiency of conservation plans. While sites initially selected as cost-efficient remained so through time, total plan costs increased, decreasing each plan’s ability to represent all species for a given budget. This emphasizes the urgent need for conservation within Canada’s farmland.
4

Assessing the Cumulative Effects of Environmental Change on Wildlife Harvesting Areas in the Inuvialuit Settlement Region through Spatial Analysis and Community-based Research

Tyson, William 15 December 2015 (has links)
Arctic ecosystems are undergoing rapid environmental transformations. Climate change is affecting permafrost temperature, vegetation structure, and wildlife populations, and increasing human development is impacting a range of ecological processes. Arctic indigenous communities are particularly vulnerable to environmental change, as subsistence harvesting plays a major role in local lifestyles. In the Inuvialuit Settlement Region (ISR), in the western Canadian Arctic, indigenous land-users are witnessing a broad spectrum of environmental changes, which threaten subsistence practices. Local cumulative effects monitoring programs acknowledge the importance of subsistence land use; however there are few cumulative effects assessments that measure the impact of environmental change on land-based activities. My MSc addresses this gap with a broad-scale spatial inventory that measures the distribution of multiple disturbances in the mainland ISR, and assesses their overlap with community planning areas, land management zones, and caribou harvesting areas. I also generated nine future disturbance scenarios that simulate increases in both human development and wildfire occurrence, in order to understand how additional environmental change may affect the availability of un-impacted harvesting lands. I used the conservation planning software, Marxan, to assess the impact of increasing environmental perturbations on the availability and contiguity of 40 subsistence harvesting areas. Results show that the study region is already impacted by multiple environmental disturbances, and that these disturbances overlap considerably with wildlife harvesting areas. This limits the success of Marxan runs that attempt to conserve high percentages of subsistence use areas. It becomes increasingly difficult to conserve large, contiguous assortments of wildlife harvesting areas when using Marxan to assess conservation potential in future disturbance scenarios. In a separate study, I conducted 20 semi-structured interviews in the communities of Inuvik, Aklavik, and Tuktoyaktuk that explored the impact of environmental change on Inuvialuit land-users. Participants in my study indicated that wildlife harvesting in the region is being affected by a range of environmental disturbances and that this change is typically considered to be negative. Climate change-related disturbances were noted to affect travel routes, access to harvesting areas, wildlife dynamics, and the quality of meat and pelts. Human activity, such as oil exploration, was noted to impact both wildlife populations and harvesters’ ability to use the land. These observations are an important contribution to local cumulative effects monitoring because they highlight local accounts of environmental change, which are often missed in broad-scale assessments, and they emphasize the concerns of local land-users. This underscores the importance of including indigenous insights in cumulative effects monitoring and suggests that combining quantitative assessments of environmental change with the knowledge of local land-users can improve regional cumulative effects monitoring. / Graduate
5

Integrating systematic conservation planning and ecosystem services : an indicators approach in the Hill Country of Central Texas

Fougerat, Matthew Gerald 30 September 2014 (has links)
Ecosystem services are the aspects of the environment utilized to produce human well-being and are key elements of landscape sustainability. Increasingly, measures of ecosystem services are being incorporated into conservation decision making. However, a framework for evaluating systematic conservation planning ranked selection scenarios with indicators of ecosystem services has not been developed. Using the Central Texas counties of Blanco, Burnet, Hays, Llano, San Saba, and Travis as a study, a suite of spatially explicit modeling tools, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), are used to quantify carbon storage, soil conservation, and water provision. A fourth service metric, ecosystem richness, is derived using Texas Parks and Wildlife ecological systems classification data. The values of these four services are then used to evaluate four conservation scenarios, developed in conjunction with a local conservation non-profit, Hill Country Conservancy (HCC), and derived using Marxan decision-support software. The evaluation process consists of both geographic information system (GIS) and statistical analysis. GIS based overlay analysis is used to identify areas of multiple ecosystem service overlap. Spearman correlation tables are used to test the spatial relationship among ecosystem services, as well as the relationship among each of the four conservation scenarios. Wilcox-Mann-Whitney U tests (WMW) are used to assess the statistical significance of each scenario’s ecosystem service values as compared to the values of a random control scenario. The results of this work reinforce the findings that there is often significant variability in the spatial congruence of multiple ecosystem services and their provision across a landscape. This work also supports the conclusion that the targeting of ecological phenomena for conservation concurrently targets areas supporting multiple ecosystem services. More distinctively, the results verify the capacity of ecosystem service indicators to effectively inform an iterative systematic conservation planning process. At the local landscape-scale, this work provides HCC with defensible support of their conservation decisions based not only on organizational priorities, but also on ecosystem service values. More broadly, this work provides a framework for evaluating conservation scenarios with spatially explicit values of ecosystem services which can be replicated across a wide range of project scales and objectives. / text
6

Cost-effective Conservation Planning for Species at Risk in Saskatchewan’s Milk River Watershed: The Efficiency Gains of a Multi-species Approach

Entem, Alicia R Unknown Date
No description available.
7

Designing Local-Scale Marine Protected Area Networks in the Central Saudi Arabian Red Sea

Khalil, Maha T. 12 1900 (has links)
Coral reefs around the world are at risk from overexploitation and climate change, and coral reefs of the Red Sea are no exception. Science-based designation of marine protected areas (MPAs), within which human activities are restricted, has become a popular method for conserving biodiversity, restoring degraded habitats, and replenishing depleted populations. The aim of this project was to explore adaptable methods for designing locally-manageable MPAs for various conservation goals near Thuwal in the central Saudi Arabian Red Sea while allowing human activities to continue. First, the potential for using simple spatial habitat distribution metrics to aid in designing MPAs that are well-connected with larval supply was explored. Results showed that the degree of habitat patchiness may be positively correlated with realized dispersal distances, making it possible to space MPAs further apart in patchier habitats while still maintaining larval connectivity. However, this relationship requires further study and may be informative to MPA design only in the absence of spatially-explicit empirical dispersal data. Next, biological data was collected, and the spatial variation in biomass, trophic structure, biodiversity, and community assemblages on Thuwal reefs was analyzed in order to inform the process of prioritizing reefs for inclusion in MPA networks. Inshore and offshore reef community assemblages were found to be different and indicated relatively degraded inshore habitats. These trends were used to select species and benthic categories that would be important to conserve in a local MPA. The abundances of these “conservation features” were then modeled throughout the study area, and the decision support software “Marxan” was used to design MPA networks in Thuwal that included these features to achieve quantitative objectives. While achieving objectives relevant to fisheries concerns was relatively more challenging, results showed that it is possible to design a local MPA that achieves fisheries and biodiversity goals simultaneously. However, future work should focus on expanding the biological dataset and on acquiring socio-economic data in order to formulate a comprehensive local management plan.
8

Using Anthropogenic Risks to Inform Salmonid Conservation at the Landscape Scale

Witt, Andrew W. 01 August 2018 (has links)
The expansion and industrialization of humanity has caused many unforeseen consequences to the natural world. Due to the importance of freshwater for people, rivers have been particularly altered to meet human needs, often at the expense of the natural world. Supplying water for farms, industries, and cities has reshaped the natural state of rivers by altering river paths, chemistry, and species compositions. These changes have harmed many species that prospered before widespread human alterations, including the native trout and salmon of western North America. As human populations continue to grow, new threats will surface for rivers, and the trout and salmon that call rivers home. As a result, many scientists have considered how to assess and counter-act threats to trout and salmon. Often, efforts focus around rehabilitating stretches of river, but do not consider large-scale watershed conditions,which may be responsible for chronic stream degradation. Tools have been developed to guide decision making for coordinating conservation efforts that consider the multitude of risks facing trout and salmon. In this thesis I implemented these tools to help managers and decision makers understand how risks affect their conservation efforts. Two examples are provided, with the first considering development and resource extraction risks to Pacific salmon spawning habitat in Alaska. The second example considers climate, development, and competition risks for cutthroat trout, throughout Utah. Results from both examples clarify that managers who consider risks while conducting conservation yield greater results than managers who attempt to avoid risks. The findings here intend to inform future conservation effort for trout and salmon, and also clarify the importance of risk management in conservation.
9

The Preservation and Protection of Native Biodiversity in the Guadalupe Nipomo Dunes Complex

Whitaker, Lindsey M, Ritter, Matthew, Steinmaus, Scott J., Hall, Jonathan 01 August 2016 (has links) (PDF)
The Guadalupe Nipomo Dunes Complex (GNDC) is located within the California Floristic Province, a biodiversity hotspot characterized by high rates of endemism and exceptional loss of habitat. In 1980, the US Fish and Wildlife Service described the GNDC as, “the most unique and fragile ecosystem in the State of California,” and ranked it first on a list of 49 habitat areas needing state protection. It is the largest coastal dune area in California and it is one of the last remaining, relatively intact ecosystems of its type and size in the western United States. The growing recognition of species decline and the limited number of dollars allocated to conservation and restoration have led to development of new conservation planning software and conservation strategies. Marxan and Zonation were selected for this project due to their worldwide acceptance in biodiversity conservation planning as well as their specialization in identifying priority zones for conservation. This document describes the unique use of conservation planning software to select areas for resource allocation. It outlines the process of selecting conservation targets, the habitats and species important to overall health of an ecosystem, by using the expert involvement approach. Most importantly, this document outlines areas of high biodiversity that will later be used to allocate resources for the preservation and protection of biodiversity within the Guadalupe Nipomo Dunes Complex. Introduced species are the second-leading cause (after habitat degradation/loss), causing or contributing to the decline in species abundance and diversity. Ehrharta calycina Smith has become highly invasive in the coastal dune communities of Central and Southern California and currently holds a “high” CAL-IPC inventory rating, defined as a species with severe ecological impacts on physical processes, plant and animal communities and vegetation structure as well as reproductive biology and other attributes conducive to moderate to high rates of dispersal and establishment. Ehrharta calycina is a prolific seeder and stores its seeds annually in the soil, collecting a substantial seedbank. Little is known about E.calycina outside its native range, as its invasion into California coastal ecosystem is fairly recent. A field experiment in the Guadalupe Nipomo Dunes Complex assessed the contribution of seeds originating from the seedbank as compared to seeds from above ground either dropping from maternal plants or blown in from outside the plots to the establishment of new E. calycina cover. After a nine month perios, new E. calycina cover from both sources was not significantly different. Visible coverage of E. calycina began 77 days (November 24, 2015) after plot installation. After nine months of surveying, coverage reached 19% in the Seedbank Present treatment and 21% in the Seedbank Absent treatment. There was no significant effect associated with the slope and aspect of the experimental locations. This experiment will aid in management of this invasive species by educating land managers to focus on preventing current seed production of established individuals as those sources of seed were as important as those originating in the seedbank. Stimulating germination of seeds from the seedbank with a concomitant management strategy such as herbicide application or physical removal will likely be the most effective methods for dealing with seeds in the seedbank.
10

Conservation des habitats marins soumis à des usages multiples : méthodes, objectifs et contraintes pour l'optimisation d'un réseau d'Aires Marines Protégées en Manche Orientale / Conservation of marine habitats under multiple human uses : Methods, objectives and constraints to optimize a Marine Protected Areas network in the Eastern English Channel

Delavenne, Juliette 30 November 2012 (has links)
La Manche orientale représente une zone économique importante qui supporte diverses activités anthropiques comme le tourisme, le transport maritime et l’exploitation de ressources vivantes ou minérales. De plus, cette région possède un riche patrimoine biologique illustré par sa grande diversité d’habitats. Les Aires Marines Protégées (AMP) sont souvent évoquées comme un instrument de gestion permettant d’aménager l’exploitation durable de ces ressources marines, dans le cadre d’une gestion écosystémique intégrée et responsable. Si les Etats ont pour obligation de créer des réseaux d’AMPs dans leurs eaux nationales, chacune d’elles est souvent localisée au cas par cas. Afin de coordonner la mise en place des différents réseaux d’AMPs, une démarche de planification spatiale systématique de la conservation est de plus en plus encouragée. Cette démarche a pour but de proposer un réseau d’AMP qui soit cohérent, même dans un contexte transfrontalier, comme c’est le cas en Manche orientale. Les travaux de recherche menés lors de cette thèse apportent ainsi une contribution scientifique à la mise en cohérence de l’aménagement des activités anthropiques avec les objectifs de conservation de l’écosystème marin de Manche orientale. Dans le cadre d’une approche de conservation intégrée, toute la biodiversité de la Manche orientale doit être représentée. Pour cela, en complément des typologies benthiques existantes dans la zone, une typologie des masses d’eau a été proposée et validée avec différents jeux de données d’espèces pélagiques. Marxan et Zonation, deux logiciels largement répandus en planification de la conservation ont été comparés dans le processus de conception du réseau d’AMP en Manche orientale. La conclusion a été que Marxan serait le logiciel utilisé pour la suite des analyses. En effet, ce logiciel est conçu pour atteindre clairement les cibles de conservation, ce qui facilite l’interprétation des résultats.Puis une étape essentielle de planification de la conservation a été réalisée à travers une analyse des lacunes (gap analysis) à l’échelle de la Manche orientale. Elle a permis de montrer que le réseau d’AMP existant atteint les cibles de conservation calculées dans cette thèse et qu’il couvre 33% de la Manche orientale. Il faut toutefois noter que l’étude des possibles lacunes au niveau de la gestion des AMPs n’a pu être réalisée de façon approfondie car la majorité de ces AMPS ne possèdent pas encore de plan de gestion défini.Finalement, l’influence de l’intégration des activités humaines dans le processus de conception du réseau d’AMP a été explorée grâce à l’utilisation de données d’effort de pêche et de données de débarquements. De plus, d’autres informations sur le trafic maritime, les extractions de granulats marins et les potentielles zones d’éoliennes en mer ont été ajoutées pour prendre en compte la totalité des usages et réglementation qui génèrent des contraintes spatiales en Manche orientale. / The eastern English Channel is a significant economic area that supports a number of human-based activities, such as tourism and recreational activities, international ports and shipping, and the extraction of both living and mineral resources. In addition, the region supports a number of important marine biological features and large habitat diversity. Marine Protected Areas (MPAs) are increasingly used as a management tool to foster a sustainable exploitation of marine resources in an ecosystem based management framework. All European countries have a legal obligation to develop MPA networks in their national waters. However, there has to date been only limited attempts to coordinate the design and positioning of such networks at an international level and the use of a systematic conservation planning approach is now recommended. This process aims to propose a coherent MPA network, even in a trans-boundary context as in the eastern English Channel (EEC). The studies conducted in this thesis contribute to the scientific knowledge needed to support both anthropogenic activities and conservation objectives in the eastern English Channel.The representation of the whole biodiversity of the eastern English Channel is important in a context of an integrated conservation approach. With this objective, to complete the existing benthic typologies, a pelagic typology was produced and validated with various pelagic species distribution data to ensure that the total biodiversity of the eastern English Channel would be considered.Marxan and Zonation, two widely used conservation planning software packages that provide decision support for the design of reserve systems were compared in the MPA network design process in the EEC. It was found that Marxan was most suitable for subsequent analyses in this thesis because it found reasonably efficient and clear solutions to the problem of selecting a system of spatially cohesive sites that met a suite of biodiversity targets, and the results were easily interpretable.Then, as it is an essential step in a conservation planning approach, a gap analysis was realized at the scale of the EEC. The currently proposed network met conservation targets proposed in this thesis and was found to cover 33% of the EEC. However, a correct assessment of management gaps was not possible as a major part of these MPA do not have management rules yet.Finally, the influence of the human activity data on the MPA design process was studied using landings and fishing effort data. Other information on maritime traffic, aggregate extraction or offshore windmills zones, and on-going MPA projects were also added to consider the whole set of uses and regulations that generate spatial constraints in the eastern English Channel.

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