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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.
111

An evaluation of the conservation of New Zealand's threatened biodiversity : management, species recovery and legislation : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Auckland, New Zealand

Seabrook-Davison, Mark Nicholas Hawdon January 2010 (has links)
Content removed from thesis due to copyright restrictions: Seabrook-Davison, M. N. H., Weihong, J. J. & Brunton, D. H. (2010). "Survey of New Zealand Department of Conservation staff involved in the management and recovery of threatened species." Biological Conservation, 143: 212-219. doi: 10.1016/j.biocon.2009.10.005. Seabrook-Davison, M. N. H., Ji, W. & Brunton, D. H. (in press). "New Zealand lacks comprehensive threatened species legislation -- comparison with legislation in Australia and the USA." Pacific Conservation Biology, 16. / It is only recently that New Zealand wildlife managers have become aware of both the taxonomic range of New Zealand’ indigenous biodiversity and the number of species threatened with extinction. The entire New Zealand archipelago has been described as a biodiversity hotspot; a term with both negative and positive connotations as although its biodiversity is unique and diverse, it has lost three quarters of its primary vegetation and much of its remaining endemic biota is in decline. This thesis evaluated aspects of New Zealand’s approach to the management of biodiversity with an emphasis on methods used in the recovery of threatened species. Possible solutions are presented that New Zealand could investigate to improve the delivery of species recovery. A survey was conducted amongst Department of Conservation (DOC) staff to investigate management tools available to them. Results suggest that inadequate resources, staff shortages and an overwhelming workload have resulted in a failure to achieve comprehensive recovery of threatened species. A review of New Zealand wildlife conservation legislation and a comparison with the USA Endangered Species Act 1973 and Australian Environment Protection and Biodiversity Conservation Act 1999, suggests that a lack of dedicated threatened species legislation is hindering the effective recovery of New Zealand’s threatened species. The thesis concludes that New Zealand has the advantage of a large conservation estate but lacks an integrated national management approach to the conservation of its biodiversity. Considerable improvement of the management and recovery of threatened species can be achieved with the enacting of dedicated threatened species legislation. Keywords: Threatened species, biodiversity, biodiversity hotspot, conservation, management, recovery plans, recovery groups, Department of Conservation, legislation, threat classification system, listing, ecological function, ecosystem services, staff survey, New Zealand
112

An evaluation of the conservation of New Zealand's threatened biodiversity : management, species recovery and legislation : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Auckland, New Zealand

Seabrook-Davison, Mark Nicholas Hawdon January 2010 (has links)
Content removed from thesis due to copyright restrictions: Seabrook-Davison, M. N. H., Weihong, J. J. & Brunton, D. H. (2010). "Survey of New Zealand Department of Conservation staff involved in the management and recovery of threatened species." Biological Conservation, 143: 212-219. doi: 10.1016/j.biocon.2009.10.005. Seabrook-Davison, M. N. H., Ji, W. & Brunton, D. H. (in press). "New Zealand lacks comprehensive threatened species legislation -- comparison with legislation in Australia and the USA." Pacific Conservation Biology, 16. / It is only recently that New Zealand wildlife managers have become aware of both the taxonomic range of New Zealand’ indigenous biodiversity and the number of species threatened with extinction. The entire New Zealand archipelago has been described as a biodiversity hotspot; a term with both negative and positive connotations as although its biodiversity is unique and diverse, it has lost three quarters of its primary vegetation and much of its remaining endemic biota is in decline. This thesis evaluated aspects of New Zealand’s approach to the management of biodiversity with an emphasis on methods used in the recovery of threatened species. Possible solutions are presented that New Zealand could investigate to improve the delivery of species recovery. A survey was conducted amongst Department of Conservation (DOC) staff to investigate management tools available to them. Results suggest that inadequate resources, staff shortages and an overwhelming workload have resulted in a failure to achieve comprehensive recovery of threatened species. A review of New Zealand wildlife conservation legislation and a comparison with the USA Endangered Species Act 1973 and Australian Environment Protection and Biodiversity Conservation Act 1999, suggests that a lack of dedicated threatened species legislation is hindering the effective recovery of New Zealand’s threatened species. The thesis concludes that New Zealand has the advantage of a large conservation estate but lacks an integrated national management approach to the conservation of its biodiversity. Considerable improvement of the management and recovery of threatened species can be achieved with the enacting of dedicated threatened species legislation. Keywords: Threatened species, biodiversity, biodiversity hotspot, conservation, management, recovery plans, recovery groups, Department of Conservation, legislation, threat classification system, listing, ecological function, ecosystem services, staff survey, New Zealand
113

Genetic analysis of the otter population (Lutra lutra) in Kristianstad’s Vattenrike Biosphere Reserve, Sweden / Genetisk analys av utterpopulationen (Lutra lutra) i Biosfärområde Kristianstads Vattenrike

Bergman, Sanne January 2017 (has links)
During the past century the Swedish otter (Lutra lutra) population showed a rapid decline in abundance and genetic diversity. Among the most affected areas was the southern province of Skåne. After prohibiting hunting of otters and banning harmful pollutants like PCB, Swedish populations slowly recovered. To some areas the otter returned late, like Kristianstad in north-eastern Skåne. Here, the River Helge å enters Kristianstad’s Vattenrike, Biosphere Reserve and forms a biodiverse wetland. By 2011, otters had established once more along the river. In recent years, a female otter with cubs have appeared outside Vattenriket visitor’s centre “naturum”, to the joy of inhabitants and visitors. In Kristianstad, otters have become a recurring winter attraction. However, not much is known about this new population. For assessment of abundance and genetic diversity, microsatellite variation was investigated among now-living individuals from eleven sites in the Biosphere reserve, and stored museum samples from ten otters with origins in North-eastern Skåne. Using a non-invasive methodology, investigated DNA was extracted from faeces and muscle tissue from dead individuals. Multiple replicate screening was performed to detect errors in genotyping procedures. Results show the presence of three now-living individuals (two males and one female). Now-living otters and museum specimens from north-eastern Skåne were not closely related. Sampled individuals show Hardy-Weinberg Equilibrium, but their heterozygosity is very low. Results suggest that, even though some individuals may remain undetected, low admixture of new genes may be a cause for concern. For long-term protection and management in Kristianstad’s Vattenrike, Biosphere Reserve, further knowledge is needed about our new and precious otter population. / Den svenska utterstammen (Lutra lutra) genomgick drastiska populationsminskningar under mitten av 1900-talet. Minskningen ledde till en förlust av genetisk diversitet i många områden, och bland de värst drabbade var Skåne. Uttern blev fredad från jakt och ett förbud mot det skadliga miljögiftet PCB infördes, vilket skapade förutsättningar för utterpopulationen i Sverige att långsamt återhämta sig i antal. Men uttern återvände sent till vissa områden, som Kristianstad i Nordöstra Skåne. Genom staden Kristianstad rinner Helge å, som formar vidsträckta, artrika våtmarker i Biosfärområde Kristianstads Vattenrike. Uttern visade inga tecken på återkomst till området förrän 2011. De senaste åren har en utterhona med ungar regelbundet visat sig vid besökscentret ”naturum”, till glädje för stadens invånare och besökare. Uttrarna har blivit en återkommande vinterattraktion i Kristianstad. Men kunskapen om den nya populationen är begränsad. För uppskattning av antal och genetisk diversitet, undersöktes mikrosatellitvariationer hos nu levande individer från elva lokaler i Vattenriket. För jämförelse inkluderades arkiverade prover från Naturhistoriska Riksmuseets ”Miljöprovbank”, från tio döda uttrar med ursprung i Nordöstra Skåne. Med icke-invasiva metoder undersöktes DNA som extraherats från avföring- och muskelvävnad. Multipel replikatanalys gjordes för detektering av eventuella fel i genotypningsproceduren. Resultaten visar förekomsten av tre nu levande individer i Vattenriket (två hanar och en hona). Det är dock troligt att en- eller flera nu levande individer kan ha undkommit identifiering. Individerna var inte nära släkt med museiexemplaren från Nordöstra Skåne. Studerade individer är i Hardy-Weinberg jämvikt, men heterozygositeten är låg. Låg heterozygositet kan bero på en låg genomblandning i populationen, vilket kan vara en anledning till oro och bör undersökas närmre. Det behövs ytterligare kunskap och studier för att långsiktigt skydda och förvalta den nya, värdefulla utterpopulationen i Kristianstads Vattenrike.
114

Utilidad del Índice Neutrófilo-Linfocito como factor pronóstico de Aborto Espontáneo en gestantes con y sin amenaza de aborto: Revisión sistemática y Meta-análisis / Role of the Neutrophil-Lymphocyte Ratio as a prognostic factor for Spontaneous Abortion in pregnant women with and without threatened abortion: systematic review and meta-analysis

Bazo Rojas, Andrea Lisamarie, Ramos Nicoll, Mirtha Patricia 24 February 2022 (has links)
Antecedentes: El aborto espontáneo es la pérdida fetal espontánea antes de la 20va semana gestacional. 1 de 4 embarazos identificados terminan en aborto, resultando en una complicación frecuente del primer trimestre. El índice neutrófilo-linfocito (INL) surge como posible marcador pronóstico por su utilidad en otras enfermedades inflamatorias. Nuevas evidencias comprueban su asociación en pacientes con y sin amenaza de aborto, sin embargo aún hay estudios que no terminan de establecer una asociación. Objetivos: Evaluar si existe asociación entre un mayor valor de INL con una mayor probabilidad de aborto espontáneo en gestantes con y sin amenaza de aborto. Materiales y métodos: Se realizó una búsqueda sistemática de casos y controles y cohortes en PubMed, Scopus, Medline, Embase, Google Scholar, y Web of Science hasta agosto de 2020. Se evaluaron las medias del INL en todos los casos. El análisis por subgrupos permitió evaluar causas de heterogeneidad. Se aplicó la escala Newcastle Ottawa y el test de Egger para evaluación de sesgos. Se usó Revman 5.2 y Stata 14 para el análisis. Resultados: Se obtuvieron 10 estudios para el meta-análisis. El Odds Ratio (OR) favorecía al aborto, pero no fue significativo (OR = 0.83; IC 95% = 0.55, 1.26). Se halló una heterogeneidad alta (I2 = 88%) y el test de Egger descartó el efecto de pequeños estudios (p = 0.812). Conclusiones: No hay asociación entre el valor de INL y una mayor probabilidad de desenlace en aborto espontáneo en las gestantes que presenten o no amenaza de aborto. / Background: Spontaneous abortion is the spontaneous loss of the fetus before the 20th week of gestation. One out of four of identified pregnancies end in abortion, resulting in a frequent first trimester complication. The neutrophil-lymphocyte ratio (NLR) emerges as a possible prognostic marker in view of its usefulness in other inflammatory diseases. Recent studies have confirmed its association in patients with and without threatened abortion, however there are still studies that do not establish an association. Objective: To assess whether there is an association between a higher NLR value and a higher probability of spontaneous abortion in pregnant women with and without threatened abortion. Material and methods: A systematic search for cases and controls and cohorts was carried out in PubMed, Scopus, Medline, Embase, Google Scholar, and Web of Science until August 2020. NLR means were evaluated in all cases. Subgroup analysis was used to assess causes of heterogeneity. The Newcastle Ottawa scale and Egger's test were applied to assess biases. Revman 5.2 and Stata 14 were used for the analysis. Results: Ten studies were obtained for the meta-analysis. The Odds Ratio (OR) was not significant despite favoring the occurrence of abortion (OR = 0.83; IC 95% = 0.55, 1.26). High heterogeneity was found (I2 = 88%) and the Egger test ruled out the effect of small studies (p = 0.812). Conclusions: There is no association between the NLR value and a higher probability of a spontaneous abortion outcome in pregnant women with or without threat of abortion. / Tesis
115

Ecology Of Non-Breeding And Breeding Crested Caracaras (Caracara cheriway) In Florida

Dwyer, James F. 14 June 2010 (has links)
Like many species, Florida's population of Northern Crested Caracaras (Caracara cheriway, hereafter "caracara") is likely declining due to loss of breeding habitat. Consequently, management-oriented restrictions on landscape modification are applied where breeding occurs, but management rarely is extended beyond breeding areas. Focusing management on breeding areas can be effective if all caracaras occupy breeding areas, all breeding areas are detected, and no intermittent breeding occurs. Management may not operate as intended if any of these criteria are unmet. To explore this possibility, I investigated the movement, habitat, survival, and social biology of non-breeding caracaras. I also investigated long-term occupancy of breeding habitat, and factors contributing to detection of breeding. Non-breeding caracaras occupy areas much larger than individual breeding territories, particularly during breeding seasons. Pastures occupied by cattle were the most used habitat, but non-breeding caracaras also occupied habitats atypical of breeding areas. Specifically, citrus groves were occupied extensively, and row crops were used particularly during breeding seasons. Non-breeding caracaras also shared communal roosts, sometimes with hundreds of conspecifics, and roosts were occupied year-round. Survival of non-breeding caracaras was lowest during breeding seasons. Adult non-breeding caracaras persisted in groups for multiple years without establishing breeding territories. This implies that breeding habitat is limited and saturated. Given the proportion of adults in groups, adults also were the first to find carrion more often than expected. Apparently, young caracaras benefit from grouping by following adults. I found caracaras at all sampled breeding areas where nests were originally documented during the 1990s, and found nests at 83% of territories where nests likely existed. I also found that observer experience, visit start time, and weather affected the probability that a nest would be detected. Thus, not all caracaras occupy breeding areas, and not all breeding attempts are likely to be detected. Long-term occupancy of breeding areas should render annual verification of nesting unnecessary as a trigger for maintaining management actions. Rather management should persist even without confirmation of annual breeding. Caracara management also may be optimized through supporting the non-breeding population by maintaining a matrix of cattle pasture and citrus groves, particularly around roosts. / Ph. D.
116

A Multidisciplinary Approach to Restoration of Butternut (Juglans cinerea)

Andrea N Brennan (9390080) 16 December 2020 (has links)
<div>Anthropogenically driven global change is disrupting ecosystems and habitats of many plant species, straining the ability of native species to survive and reproduce. The overarching goal of this research was to holistically work towards restoration of a threatened tree species by connecting research from different disciplines. In order to do so, the threatened butternut tree (<i>Juglans cinerea</i>) and its hybrids were used as a case study. Hybridization can incorporate stress tolerance in plants and could be a potential restoration tool. Evidence in some wild butternut populations indicates that naturalized hybrids of butternut with Japanese walnut (<i>Juglans ailantifolia</i>) may be more tolerant to butternut canker disease (BCD) than butternut, but this has not been formally tested. Thus, chapter 2 examined potential BCD tolerance within and between unadmixed and hybrid butternut inoculated with two BCD fungal isolates. Differences in canker growth were observed by fungal isolate, which could help to explain some differences in BCD severity found among butternut populations. Smaller and fewer cankers and greater genetic gains were detected in hybrid families, demonstrating that hybrids warrant further evaluation as a possible breeding tool for developing BCD-resistant butternut trees.</div><div>However, even with increased disease tolerance, hybrids must possess similar ecophysiological tolerances to their native progenitor to be an effective replacement. Butternut is extremely cold hardy, but Japanese walnuts are native to a warmer ecosystem, indicating potential disparities in extreme temperature tolerances between the two species and their hybrids. Thus, samples from mature trees were subjected to cold and heat treatments to compare relative extreme temperature tolerances within butternut and between butternut, Japanese walnut, and their hybrids. Within butternut, trees from colder areas exhibited less cold damage than those from warmer areas. Differences in heat damage among provenances occurred but did not follow a clear trend. Butternut exhibited greatest cold tolerance, Japanese walnut exhibited greatest heat tolerance, and hybrids were intermediate. Thus, the utility of hybrids for restoration could be limited at the extremes of the species’ distributions.</div><div>A second, but different type of freeze test was conducted for chapter 4 using seedlings to gain a more nuanced understanding of cold tolerance within butternut and between butternut and its hybrids. No survival or damage differences were detected in butternut provenances, although seedlings from the coldest provenances experienced more delayed budbreak at the two warmest treatments than those from warmer provenances. Interspecific differences were not observed in dieback but were detected in survival and budbreak. The hybrids had greater survival than butternut from warmer provenances at the lowest temperature treatment (-38 °C), but given that temperatures that low are extremely unlikely to occur in those provenances, it is not anticipated to give the hybrids an advantage if planted in those areas. However, the hybrids’ earlier budbreak could limit the success of restoration with these hybrids in the coldest extents of butternut’s range. </div><div>If hybrids, as well as genetically modified (GM) trees, are successfully developed for effective disease tolerance and to serve as an ecologically suitable replacement, success of restoration using hybrids will ultimately depend on those directly responsible for replanting efforts. A survey was administered to land managers in 46 organizations in Indiana to gauge perceptions of hybrid and GM trees, as well as current use of hybrid trees. Land managers had stronger concern for ecological, rather than economic, issues. Agreement was highest for using hybrid and GM trees for “conservation and restoration of at-risk species”, “timber production”, and “non-timber products (fruit, syrup, etc.)”. However, perceptions varied by characteristics, such as concern type, age, and the type of land they managed. Ecological concern and the type of land being managed most strongly predicted current hybrid use. Overall, results indicate the majority of land managers in Indiana would likely be agreeable to recommendations towards using hybrids. However, most nonetheless had strong ecological concerns about their suitability as a native replacement. It is important to note, though, that consistent with the results of previous studies, great variation was seen within the performance and characteristics of the butternut hybrids in chapters 2-4. Thus, it may be possible with careful selection and breeding to harness this variation to develop disease tolerant and ecologically similar hybrids acceptable to land managers.</div>
117

La gestion prévisionnelle des emplois et des compétences du point de vue du droit social / Forward planning of employment and skills in the social law's point of view

Leca, Marie 30 November 2015 (has links)
La gestion prévisionnelle des emplois et des compétences est une locution appartenant au vocabulaire gestionnaire ce qui lui confère une dimension organisationnelle indéniable et originelle. En droit la notion bénéficie depuis son apparition dans le Code du travail d'une indéniable publicité bien qu'elle préexistait à cette juridification. Elle garde malgré cela une certaine dose de mystère qui tient en partie aux relations qu'elle a longtemps entretenu avec les licenciements pour motif économique, à la pluralité des thématiques qui la composent ainsi qu'aux évolutions constantes de son régime juridique. Depuis qu'elle est devenue un objet du droit social, elle a bénéficié de multiples enrichissements légaux et jurisprudentiels. Partant, la présente étude, qui commandait une approche d'ensemble de la notion, tend à la détermination des contours de la gestion prévisionnelle des emplois et des compétences du point de vue du droit social. / He management of jobs and skills is a phrase belonging to the manager vocabulary which gives it a distinct and original organizational dimension. By law the concept has since appeared in the Labour Code of undeniable advertising although it existed before this juridification. She keeps nevertheless a certain dose of mystery partly due to the relationship it has long maintained with redundancies, with the plurality of themes that compose it and the constant changes in its legal system. Since it became an object of social law, she received multiple legal and jurisprudential enrichment. Accordingly, this study which commanded an overall approach to the concept, tends to determine the contours of the management of jobs and skills of the labor law perspective.
118

Programa de proteção a vítimas e testemunhas ameaçadas - Provita: um estudo sobre o serviço social

Santa, Elaine Christina 28 September 2006 (has links)
Made available in DSpace on 2016-04-29T14:16:53Z (GMT). No. of bitstreams: 1 CD 1 - SSO - Elaine Christina Santa.pdf: 360653 bytes, checksum: e8294b9deb33575061816f1118cbf33d (MD5) Previous issue date: 2006-09-28 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The purpose of this research analyses The Victims and Threatened Witnesses Program of Protection - Provita - appears, in 1996, from an initiative of the civil society in partnership with the State. As a result of this process, in July 13 1999, is promulgated the Federal Law nº 9.807, that establishes standards for the organization and maintenance of this Program. The focus of this Program is the reduction of the impunity, creating security conditions to the threatened witnesses. From a revision of the historical construction process of the national security system, it is considered as a basic guarantee instrument to the right to the life and to the security, in a context where the violence and impunity are daily expressed realities. During the research process, we aimed to better understand the inter-relations, connections and factors responsible for the existence of this Program in our Brazilian society and the Social Service role. So, the objective of this research is centered on studying the social worker job in this Program, approaching questions on its attributions, objectives and challenges. It aims to reflect on professional practices, in the prism of human rights defense, in accordance with what was praised in the Code of Professional Ethics. This research concludes the require and importance of enlargement of the responsibility of the State about execution of public security activities, when the limitations were given to the development of the service created, between other factors, by the absence of articulation with the set of public politics, essential policies for the service to the necessities of the persons in regime of protection; resource insufficiency for the formation and security of the professionals group; slowness of the judicial processing. The data, between 2000 and 2005, of 75 people protected, of which 21 testified in processes that reached the final verdict, and 20 turned in condemnatio n, illustrate both the importance and the difficulties of the Program. We also perceived that the social worker practice still is permeated by the challenge of acting and implementing the commitment with its practice citizens. This professional has the dut y of working in search for the citizenship promotion, the emancipation and to make possible the conditions of the protected person of struggle for his rights, during the protection process and over all, later / Este estudo apresenta a análise do Programa de Proteção a Vítimas e Testemunhas Ameaçadas - Provita -, que surge, em 1996, a partir de uma iniciativa da sociedade civil em parceria com o Estado. Em decorrência desse processo, em 13 de julho de 1999, é promulgada a Lei Federal nº 9.807, que estabelece normas para a organização e manutenção deste Programa. O objetivo principal do Programa é a redução da impunidade, criando condições de segurança para pessoas capazes de prestar testemunho, apesar de ameaçadas. A partir de uma revisão do processo de construção histórica do sistema de segurança nacional, é estudado como um instrumento fundamental de garantia ao direito à vida e à segurança, num contexto de violência extrema e cotidiana. O processo de pesquisa produziu uma melhor compreensão das inter-relações, conexões e fatores responsáveis pela sua existência na sociedade brasileira. A análise baseou-se na experiência profissional da autora e nos depoimentos de exprofissionais de Serviço Social pertencentes à equipe de trabalho do Provita. Teve como objetivo central estudar o papel do Serviço Social no Programa, abordando questões relacionadas às atribuições, objetivos e desafios do trabalho do assistente social. A prática profissional foi refletida pelo prisma da defesa dos direitos humanos, de acordo com o preconizado no Código de Ética profissional. Concluiu-se pela necessidade e importância da ampliação da responsabilidade do Estado quanto à execução das atividades de segurança pública, dadas as limitações ao desenvolvimento do atendimento criadas, entre outros fatores, pela ausência de articulação com o conjunto de políticas públicas, essenc iais para o atendimento às necessidades das pessoas em regime de proteção; insuficiência de recursos para a formação e segurança do corpo de profissionais; morosidade do processamento judiciário. Os dados de permanência, entre 2000 e 2005, de 75 protegidos, dos quais 21 testemunharam em processos que chegaram ao veredicto final, e 20 resultaram em condenação, ilustram tanto a importância como as dificuldades do Programa. A prática do assistente social foi sempre permeada pelo desafio do compromisso com os sujeitos de sua prática, em busca da promoção da cidadania e da emancipação, para possibilitar ao protegido condições de luta por seus direitos, durante o processo de proteção e, sobretudo, depois
119

Informed statistical modelling of habitat suitability for rare and threatened species

O'Leary, Rebecca A. January 2008 (has links)
In this thesis a number of statistical methods have been developed and applied to habitat suitability modelling for rare and threatened species. Data available on these species are typically limited. Therefore, developing these models from these data can be problematic and may produce prediction biases. To address these problems there are three aims of this thesis. The _rst aim is to develop and implement frequentist and Bayesian statistical modelling approaches for these types of data. The second aim is develop and implement expert elicitation methods. The third aim is to apply these novel approaches to Australian rare and threatened species case studies with the intention of habitat suitability modelling. The _rst aim is ful_lled by investigating two innovative approaches for habitat suitability modelling and sensitivity analysis of the second approach to priors. The _rst approach is a new multilevel framework developed to model the species distribution at multiple scales and identify excess zeros (absences outside the species range). Applying a statistical modelling approach to the identi_cation of excess zeros has not previously been conducted. The second approach is an extension and application of Bayesian classi_cation trees to modelling the habitat suitability of a threatened species. This is the _rst `real' application of this approach in ecology. Lastly, sensitivity analysis of the priors in Bayesian classi_cation trees are examined for a real case study. Previously, sensitivity analysis of this approach to priors has not been examined. To address the second aim, expert elicitation methods are developed, extended and compared in this thesis. In particular, one elicitation approach is extended from previous research, there is a comparison of three elicitation methods, and one new elicitation approach is proposed. These approaches are illustrated for habitat suitability modelling of a rare species and the opinions of one or two experts are elicited. The _rst approach utilises a simple questionnaire, in which expert opinion is elicited on whether increasing values of a covariate either increases, decreases or does not substantively impact on a response. This approach is extended to express this information as a mixture of three normally distributed prior distributions, which are then combined with available presence/absence data in a logistic regression. This is one of the _rst elicitation approaches within the habitat suitability modelling literature that is appropriate for experts with limited statistical knowledge and can be used to elicit information from single or multiple experts. Three relatively new approaches to eliciting expert knowledge in a form suitable for Bayesian logistic regression are compared, one of which is the questionnaire approach. Included in this comparison of three elicitation methods are a summary of the advantages and disadvantages of these three methods, the results from elicitations and comparison of the prior and posterior distributions. An expert elicitation approach is developed for classi_cation trees, in which the size and structure of the tree is elicited. There have been numerous elicitation approaches proposed for logistic regression, however no approaches have been suggested for classi_cation trees. The last aim of this thesis is addressed in all chapters, since the statistical approaches proposed and extended in this thesis have been applied to real case studies. Two case studies have been examined in this thesis. The _rst is the rare native Australian thistle (Stemmacantha australis), in which the dataset contains a large number of absences distributed over the majority of Queensland, and a small number of presence sites that are only within South-East Queensland. This case study motivated the multilevel modelling framework. The second case study is the threatened Australian brush-tailed rock-wallaby (Petrogale penicillata). The application and sensitivity analysis of Bayesian classi_cation trees, and all expert elicitation approaches investigated in this thesis are applied to this case study. This work has several implications for conservation and management of rare and threatened species. Novel statistical approaches addressing the _rst aim provide extensions to currently existing methods, or propose a new approach, for identi _cation of current and potential habitat. We demonstrate that better model predictions can be achieved using each method, compared to standard techniques. Elicitation approaches addressing the second aim ensure expert knowledge in various forms can be harnessed for habitat modelling, a particular bene_t for rare and threatened species which typically have limited data. Throughout, innovations in statistical methodology are both motivated and illustrated via habitat modelling for two rare and threatened species: the native thistle Stemmacantha australis and the brush-tailed rock wallaby Petrogale penicillata.
120

Ecological assessment of salmonid populations in a country undergoing rapid environmental and socioeconomic transitions (Mongolia)

Kaus, Andrew 11 April 2018 (has links) (PDF)
Mongolia is currently undergoing a rapid socioeconomic transition with extensive development driven by increased mineral resource extraction and large scale agriculture and pastoral expansion. There has also been unprecedented urbanisation and continued population growth that has placed added pressure on the ageing public infrastructure including power stations and waste water treatment plants. As a result, the country’s pristine landscapes, including its vast freshwater ecosystems, are now facing widespread degradation, contamination and species losses in the most impacted regions. The proposed large-scale dams and imminent climate change effects will further damage these fragile ecosystems. With a number of rivers and lakes deteriorating, resident aquatic communities, including unique fish species, have suffered significant population declines. However, a more substantial threat currently facing these fish populations is the rapid and largely unregulated rise in fishing activities within an emerging recreational fishery. Although historically fish capture and consumption has not been a traditional part of the Mongolian diet or culture, this is changing rapidly. Therefore a comprehensive set of research projects were developed and implemented across Mongolia, to gather essential information on this new fishery, while also addressing existing knowledge gaps regarding the spatial ecology and genetic structure of the main target species. In addition, a potential human health risk was evident due to the increased consumption of locally caught fish species from a heavily impacted river basin, and thus this was also investigated. Overall, the collective aim of this fisheries research was to increase the scientific understanding and knowledge across a range of issues and ultimately advise authorities on improving current management regulations and conservation strategies. It is hoped that the recommendations can assist in safeguarding the future sustainability and resilience of the threatened fish populations and the emerging recreational fishery across Mongolia for the future. A total of five fisheries related research projects were completed between 2011 and 2014, with the results from each used to formulate the conservation and management recommendations presented in this thesis. Due to the lack of knowledge regarding the emerging recreational fishery, roving creel surveys were conducted across three river basins and covered five key topics including angler demographics, fishing practices, current fishing trip data, fishing gear and costs, and angler knowledge and opinions. Fifty-eight fishing groups (n = 154 anglers) were interviewed and two angler types were identified: rural anglers with no or low incomes, who reside in the basin, fish alone or in smaller groups, fish frequently for shorter periods, and consumed fish more regularly; and urban anglers who have medium to high incomes, live in larger cities, spent more money on fishing gear / trips and fished for multiple days at a time. B. lenok was identified as the most targeted and caught species in the fishery. The results of the creel surveys confirmed increased fish consumption in the Kharaa River basin, which was identified as a potential human health risk due to the widespread heavy metal contamination from both past and present mining activities. Thus heavy metal contaminates in river water, sediment and five consumed fish species were examined at 11 sites across the basin. Heavy metals were evident in all five sampled species, with maximum muscle contents of chromium (Cr), arsenic (As), mercury (Hg) and lead (Pb) detected in fish from the middle and lower reaches, while zinc (Zn) was highly elevated in B. lenok from the upper tributaries. Elevated median contents of Cr, copper (Cu), Hg and Pb increased with trophic level, with the bioaccumulation of Hg posing the greatest threat to human health with over 10 % of all fish sampled exceeded the internationally recommended threshold for Hg in consumable fish tissue (> 0.5 µg g-1 ww). This bioaccumulation in resident fish species could lead to chronic toxicity in people who consume them regularly and have additional exposure to other sources of contamination e.g. gold mining. A further two projects were conducted that utilised passive acoustic telemetry to describe the spatial and temporal autecology, habitat use and behaviour of B. lenok in the Eroo River and H. taimen in the Onon/Balj rivers under Mongolia’s extreme seasonal conditions. The maximum longitudinal movements (home ranges) detected were more extensive than previously reported for both species with 45.3 km for B. lenok and 126.1 km for H. taimen. Increased movements were recorded in spring and summer, with individuals entering surrounding tributaries and remaining there for between four and 85 days before returning to the main river channel. The results highlighted the importance of maintaining the integrity and connectivity of tributary habitats for spawning, feeding and overwintering, as well as hydrological and thermal refuges, which will be increasingly important for these species in the region with the pending impacts of climate change. This increased knowledge relating to the spatial ecology of these threatened species can guide the design and implementation of new protective measures such as the introduction of Freshwater Protected Areas (FPAs) across Mongolia. Further research was conducted to gain a broader, multigenerational understanding of the interconnectedness between conspecific populations of H. taimen, B. lenok and T. baicalensis across the major river basins. Both molecular and nuclear markers were used to demarcate the population’s genetic structure and define Evolutionary Significant Units (ESUs) and priority populations for these species across their Mongolian distributions. Across all species, the most prominent pattern was a strong differentiation among major basins with low differentiation and weak patterns of isolation by distance within basins, which indicates high within-basin connectivity between populations, although exact patterns were not completely concordant among species. The extensive results produced from the current scientific research has facilitated the development of a comprehensive set of key recommendations for implementing new, and enhancing existing, management and conservation measures relating to Mongolia’s threatened salmonid species and its emerging recreational fishery. These recommendations include: 1. Establishing a series of Freshwater Protected Areas (FPAs) throughout Mongolia’s major river basins, with their design and location based upon the spatial ecology and genetic population structure determined by the current research results; 2. Shifting the opening date of the fishing season to encompass the entire spawning period of B. lenok (the fishery’s main target species), which appears to currently not be the case; 3. Adding the blunt-snouted lenok (B. sp.) to the prohibited species list, as it has been genetically proven to be an independent species and has a restricted distribution and low abundance in Mongolia; and 4. Introducing minimum (and potentially maximum) size limits for B. lenok and T. baicalensis, to better protect immature and pre-spawning individuals from being removed from the population. In addition, it is highly recommended to commence fisheries dependent and independent assessments in key river basins and conduct biomonitoring programs (using a bioindicator species) to track toxic heavy metal contamination and identify potential human health risks associated with consuming resident fish species from the more heavily impacted regions. The lack of knowledge of the current fishing regulations by anglers as well as the observed and reported widespread illegal fishing activities demands a wide-ranging angler education program to improve understanding and compliance within the fishery. The future survival of these threatened salmonids and the sustainability of the emerging recreational fishery in Mongolia currently hangs in the balance. However, if these scientifically based recommendations are implemented in full, and can be adequately enforced, then the responsible authorities can take a huge step forward towards reversing the current trends and preserving the country’s imperilled freshwater fish populations and their valuable aquatic ecosystems. Mongolia can be a model for freshwater species conservation and management throughout the region and the world. / Die Mongolei befindet sich derzeit in einem rasanten sozioökonomischen Übergang mit tiefgreifenden Veränderungen, die v.a. durch eine Zunahme bergbaulicher Aktivitäten sowie einen Ausbau ackerbaulicher Nutzungen wie auch der Viehwirtschaft angetrieben werden. Derzeit vollzieht sich eine noch nie dagewesene Urbanisierung und ein weiteres Bevölkerungswachstum, das auf die alternde öffentliche Infrastruktur, einschließlich Kraftwerke und Abwasserbehandlungsanlagen, einen zusätzlichen Druck ausübt. Infolgedessen zeigen sich in den weitgehend unberührten Landschaften des Landes, einschließlich seiner riesigen Süßwasser-Ökosysteme, deutliche Anzeichen von Übernutzung natürlicher Ressourcen, Umweltverschmutzung und Artenverlusten. Zukünftig geplante große Staudämme werden neben den bevorstehenden Auswirkungen des Klimawandels die Hydrologie deutlich verändern. So sind bereits deutliche Beeinträchtigungen der Fluss-und See-Ökosysteme erkennbar, insbesondere in Hinblick auf ihre aquatischen Lebensgemeinschaften. Einige der weltweit einzigartigen Fischarten haben bereits erhebliche Bevölkerungsrückgänge erlitten. Eine weitere existenzielle Bedrohung für diese Fischpopulationen ist der rasche und weitgehend un-regulierte Anstieg der Fischereitätigkeiten aus einer aufstrebenden Freizeitfischerei. Obwohl Fischfang und -konsum keine traditionellen Elemente der mongolischen Ernährung oder Kultur darstellen, vollziehen sich diesbezüglich derzeit tiefgreifende Veränderungen. Daher wurden in der Mongolei umfangreiche Forschungsprojekte geplant und durchgeführt, um wesentliche Informationen über diese neue Art der Fischerei zu sammeln und gleichzeitig bestehende Wissenslücken in Bezug auf die räumliche Ökologie und die Metapopulationsstruktur der wichtigsten Zielarten zu schließen. Darüber hinaus zeigten Untersuchungen, dass sich aufgrund des erhöhten Konsums von lokal gefangenen Fischarten aus einem stark beeinträchtigten Einzugsgebiet ein potenzielles Risiko für die menschliche Gesundheit ergibt. Insgesamt ist das übergeordnete Ziel dieser Fischereiforschung, das wissenschaftliche Verständnis und Wissen zu erweitern und letztlich die derzeitigen Managementinstrumente zu verbessern und neue Erhaltungsmaßnahmen zu ergreifen, um die Nachhaltigkeit und Widerstandsfähigkeit der bedrohten Fischartenpopulationen und die aufkommende Erholung zu sichern. Insgesamt wurden zwischen 2011 und 2014 insgesamt fünf fischereibiologische Forschungsprojekte abgeschlossen, wobei die Ergebnisse dieser Arbeiten in Erhaltungs- und Managementempfehlungen münden. Wegen des Mangels an Wissen über die aufkommende Freizeitfischerei wurden Anglerbefragungen in drei Einzugsgebieten durchgeführt, welche fünf wichtige Themen wie Angler-Demographie, Fischereipraktiken, Reisetätigkeiten, Fanggeräte und Kosten sowie Anglerwissen und Meinungen umfassten. Fünfundsechzig Angelgruppen (n = 154 Angler) wurden interviewt und zwei Anglertypen identifiziert: ländliche Angler ohne oder niedrige Einkommen, die in dem Becken wohnen, alleine oder in kleineren Gruppen fischen, häufig für kürzere Zeiten fischen und regelmäßig Fisch verzehren; und städtische Angler, die mittlere bis hohe Einkommen haben, in größeren Städten leben, mehr Geld für Fanggeräte / Ausflüge ausgegeben und typischerweise für mehrere Tage am Stück fischen. B. lenok wurde als die bevorzugte und am meisten gefangene Zielarten der Fischerei identifiziert. Die Ergebnisse der Anglerbefragungen bestätigten den erhöhten Fischkonsum im Kharaa-Einzugsgebiet, das aufgrund der weit verbreiteten Schwermetallverunreinigung aus der Vergangenheit und den gegenwärtigen Bergbauaktivitäten als potenzielles Risiko für die menschliche Gesundheit identifiziert wurde. So wurden Schwermetallverunreinigungen im Flusswasser, Sediment und fünf konsumierten Fischarten an 11 Standorten im Einzugsgebiet untersucht. Schwermetalle zeigten sich in allen fünf Stichprobenarten, wobei der maximale Muskelgehalt von Cr, As, Hg und Pb in Fischen aus dem Mittel- und Unterlauf festgestellt wurde, während Zn in B. lenok in den Oberlaufregionen stark erhöht war. Der erhöhte mediane Gehalt an Cr, Cu, Hg und Pb nahm mit trophischer Ebene zu, wobei die Bioakkumulation von Hg die größte Bedrohung für die menschliche Gesundheit darstellte, wobei über 10% aller Fischproben den international empfohlenen Schwellenwert für Hg im verzehrbaren Fischgewebe überstiegen (> 0,5 μg g-1 ww). Diese Bioakkumulation in residenten Fischarten könnte zu chronischen Intoxikationen bei Menschen führen, die sie regelmäßig konsumieren und zusätzliche Exposition gegenüber anderen Kontaminationsquellen haben, z.B. im Goldbergbau. Es wurden weitere zwei Projekte durchgeführt, die eine passive akustische Telemetrie zur Beschreibung der räumlichen und zeitlichen Autökologie, des Lebensraumnutzens und des Verhaltens von B. lenok im Eroo River und H. taimen in den Flüssen Onon und Balj unter den extremen Klimabedingungen der Mongolei verwendeten. Die maximalen Längsbewegungen (Heimatbereiche) wurden -umfangreicher als bisher angenommen- für beide Arten wurden auf 45,3 km für B. lenok und 126,1 km für H. taimen ermittelt. Im Frühjahr und Sommer wurden erhöhte Bewegungen aufgezeichnet, wobei die Individuen in die umliegenden Nebenflüsse eintraten und dort zwischen 4 und 85 Tagen verblieben, bevor sie zum Hauptfluss des Flusses zurückkehrten. Die Ergebnisse zeigen die Bedeutung der Aufrechterhaltung der Integrität und der Konnektivität von Nebenflüssen für Laichen, Nahrungssuche und Überwinterung sowie hydrologische und thermische Schutzräume, die für diese Arten in der Region mit den anstehenden Auswirkungen des Klimawandels zunehmend an Bedeutung gewinnen werden. Die verbesserten Kenntnisse der räumlichen Ökologie dieser bedrohten Arten kann die Gestaltung und Umsetzung neuer Schutzmaßnahmen wie Süßwasser-Schutzgebiete in der Mongolei wissenschaftlich fundieren und leiten. Weitere Untersuchungen wurden durchgeführt, um ein breiteres, multigenerationales Verständnis der Zusammenhänge zwischen den konkreten Populationen von H. taimen, B. lenok und T. baicalensis über die großen Flusseinzugsgebiete zu gewinnen. Sowohl molekulare als auch nukleare Marker wurden verwendet, um die genetische Struktur abzugrenzen und definieren, so z.B. evolutionär signifikante Einheiten (ESUs) und eigenständige Populationen für diese Arten einschließlich ihrer räumlichen Verteilung in der Mongolei. Über alle Arten hinweg war das deutlichste Muster eine starke Differenzierung zwischen den großen Becken mit geringer Differenzierung. Dem gegenüber stehen schwache Muster der Isolation durch die Distanz in den Becken, die eine hohe einzugsgebietsinterne Konnektivität anzeigen, obwohl exakte Muster nicht vollständig unter allen Arten übereinstimmten. Die Prioritäten der Erhaltung müssen sich auf die Verbesserung des Schutzes der vorrangigen Bevölkerungsgruppen innerhalb jeder Art und ESU konzentrieren, um die begrenzten verfügbaren Ressourcen für die Arten- und Populations-Erhaltung und fischereiliche Bewirtschaftung in der Mongolei zu maximieren. Die umfangreichen Ergebnisse aus der aktuellen wissenschaftlichen Forschung ermöglichten die Ableitung umfassender Empfehlungen für die Umsetzung neuer und die Verbesserung der bestehenden Management- und Erhaltungsmaßnahmen in Bezug auf die bedrohten Lachsarten der Mongolei und die aufkommende Freizeitfischerei. Diese Empfehlungen beinhalten 1.die Gründung einer Reihe von Süßwasser-Schutzgebieten (FPA) in den großen Flussgebieten der Mongolei auf der Grundlage der räumlichen Ökologie und der genetischen Bevölkerungsstruktur, die durch die aktuellen Forschungsergebnisse untermauert wird; 2. Eine Verschiebung des Eröffnungstermins der Fangsaison, welche im Gegensatz zur aktuellen Praxis die gesamte Laichzeit von B. lenok (die Hauptzielspezies der Fischerei); umfassen sollte; 3. Hinzufügen des Stumpfschnauzen-Lenok (B. sp.) zur Liste der besonders geschützten Arten, da er sich als eine genetisch unabhängige Spezies erwiesen hat, welche eine begrenzte räumliche Verteilung und geringe Populationsdichte in der Mongolei hat; und 4. Einführung von minimalen (und potentiell maximalen) Körpergrößenbeschränkungen für B. lenok und T. baicalensis, um die unreifen und heranwachsenden Individuen besser vor menschlichen Einflüssen zu schützen. Darüber hinaus empfiehlt es sich dringend, in den wichtigsten Flussgebieten fischereilich genutzte und nicht genutzte Fischpopulationen zu erfassen und Biomonitoring-Programme (unter Verwendung von Bioindikator-Spezies) zu implementieren, um toxische Schwermetallverunreinigungen zu verfolgen und potenzielle Risiken für die menschliche Gesundheit zu identifizieren, die mit dem Verzehr Fischen aus beeinträchtigten Regionen einhergehen. Schließlich verlangt das Fehlen von Kenntnissen über die derzeitigen Fischereiverordnungen durch Angler sowie die beobachteten und gemeldeten weitverbreiteten illegalen Fischereitätigkeiten ein weitreichendes Angler-Bildungsprogramm, um das Verständnis und die Einhaltung fischereilicher Regelungen zu verbessern. Das künftige Überleben der bedrohten Salmoniden und die Nachhaltigkeit der aufkommenden Freizeitfischerei in der Mongolei sind eng miteinander verbunden. Sofern die hier dargestellten wissenschaftlich fundierten Empfehlungen in vollem Umfang umgesetzt werden und hinreichend kontrolliert werden können, würden die zuständigen Behörden einen großen Schritt in Richtung der Umkehrung der aktuellen Trends machen und die gefährdeten Süßwasserfischpopulationen des Landes und ihre wertvollen aquatischen Ökosysteme bewahren. Die Mongolei könnte dann ein Modell für die Erhaltung und Bewirtschaftung von Süßwasserarten in der ganzen Region und der Welt werden.

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