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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.
161

Towards a Network of Marine Protected Areas in the South China Sea: Legal and Political Perspectives

Vu, Hai Dang 12 July 2013 (has links)
The once pristine and rich marine environment of the South China Sea is degrading at an alarming rate due to the rapid socioeconomic development of the region. Despite this, and because mainly of complicated sovereignty and maritime boundary disputes, coastal States have not been able to develop effective regional cooperation to safeguard the shared marine environment. This dissertation, “Towards a Network of Marine Protected Areas in the South China Sea: Legal and Political Perspectives”, researches legal and political measures to support the development of a network of marine protected areas in the South China Sea. Such a network, if properly developed, would not only help to protect the marine environment and resources of the region but also contribute to lower the tension among its coastal States. These measures should be developed in accordance with international law, based on the specific geopolitical context of the South China Sea region and take into consideration experiences in developing regional networks of marine protected areas from other marine regions. Consequently, three optional categories of measures for the development of a network of marine protected areas in the South China Sea are suggested at the end. They include national-focused measures; measures to enhance the regional cooperation; and measures to build a regime for marine protected areas and network of marine protected areas in the South China Sea. These measures could be taken alternatively or on a step-by-step basis.
162

Marketingová strategie chráněných dílen nestátních neziskových organizací v Jihočeském kraji / Marketing Strategy of Protected Workshops Non-Governmental Organizations in the South Bohemian Region

DUŠKOVÁ, Miluše January 2013 (has links)
The theme of the completed diploma thesis is A Marketing Strategy for Protected Work Places of NGOs in South Bohemia. In the theoretical part I focus on the definition and meaning of marketing, stategic management, the marketing process, the marketing environment, the buying behavior of consumers, marketing research. In the next section I describe the legislative basis for protected work places and I name protected work places of NGOs in South Bohemia. Then I describe the employment of people with disabilities, and I attempt to define the concept of a non-profit organization. For completion purposes, I briefly define the term South Bohemia. In the practical part I deal with the results of the research and draft a proposal for marketing strategies for the sale of products from protected work places. The practical part relates to the main goals of the diploma thesis. The first goal of the work was to map out a marketing strategy for protected work places of NGOs in South Bohemia. The second goal was to map out the opinions of the wider public in relation to the purchase of products from protected work places. The first stated hypothesis was: Protected work places of NGOs in South Bohemia do not optimally use the tools of the marketing mix to sell their products. The second stated hypothesis was: A marketing strategy has an effect on the sale of products in protected work places of NGOs in South Bohemia. I chose quantitative research with subsequent statistical data processing. The data was collected through standardized interview techniques and surveys. In both cases, the improbability of sampling techniques was used. The basic collection in terms of quantitative research was the management of protected work places of NGOs in South Bohemia and the wider public. Through standardized telephone interviews, the chosen collection of required data for the research was acquired. Due to the chosen technology. The survey, which in its form came close to being a questionnaire, was used in this thesis as an additional source of information, and was also used to acquire the primary data from the chosen sample. The sample was chosen at random. There were 94 total respondents. Through the research results which are related to the first goal, we can say that the explanatory function of the first hypothesis was not confirmed. In fact, protected work places of NGOs in South Bohemia use optimal tools of the marketing mix for the sale of their products. From the research results which are related to the second goal, we can say that the explanatory function of the second hypothesis was confirmed. With certainty we can say that a marketing strategy has an effect on the sale of products of protected work places of NGOs in South Bohemia.From the research results of controlled interviews with management of protected work places, it is evident that in addition to the long-term interests of the organization, protected work places are beginning to be interested in the desires and needs of their customers. They prefer segmented marketing, they monitor their competitors and concern themselves with competitive advantage. On the other hand, they do not engage in comprehensive marketing research and they do not create strategic marketing plans. In terms of the marketing mix, it was discovered that the quality of the products is important to those surveyed. In the communication mix, organizations mainly work with tools which can be used with lower costs.The research results of the wider public showed that the majority of respondents are aware of protected work places, but they consider their products to be unavailable. The main reason for the purchase of products from protected work places is to provide financial assistance. While respondents expect quality and attractively designed products for which they are willing to pay a higher price, the decisive incentive for the purchase may be lower-price products.
163

Vulnérabilité des écosystèmes montagnards aux changements globaux par une modélisation spatialement explicite -implications pour la conservation / Vulnerability of mountainous ecosystems to global change - a spatially explicit modeling approach and conservation implications

Boulangeat, Isabelle 06 June 2012 (has links)
Les conséquences des récents changements environnementaux sont déjà observables sur les écosystèmes du monde entier et menacent la biodiversité. Dans l'objectif de conserver les bénéfices que nous procurent les écosystèmes, l'enjeu est de comprendre et prédire la dynamique spatiale et temporelle des paysages et de la biodiversité afin de mieux anticiper les changements possibles et adapter les décisions de conservation. En zone de montagne, où l'environnement est très hétérogène, les effets combinés des modifications du climat et de l'agriculture sont susceptibles d'avoir un impact important sur les écosystèmes. La présente thèse a pour objectif principal de caractériser les espèces et les habitats vulnérables aux changements climatiques et changements d'utilisation des terres dans les Alpes Françaises. Elle apporte sa contribution en se basant sur des données accumulées par le Conservatoire Botanique National Alpin et le Parc national des Ecrins (PNE), et en utilisant trois angles d'approche complémentaires. Dans une première partie, les cadres théoriques expliquant la coexistence des espèces et leur répartition spatiale ont été testés empiriquement. Les patrons de rareté des plantes des Alpes françaises ont ainsi été reliés aux caractéristiques des espèces, mettant en évidence les compromis entre différentes stratégies fonctionnelles. Une seconde analyse de la répartition de 21 espèces cibles a démontré la différence entre les facteurs expliquant la présence d'une espèce à un endroit donné et ceux expliquant son abondance. Cette analyse a également permis de souligner l'importance de la dispersion et mis en évidence des dynamiques source-puits chez certaines espèces. La deuxième partie s'appuie sur les mêmes cadres théoriques et a consisté à développer un modèle dynamique de la structure et de la diversité de la végétation. Ce modèle a été calibré et validé sur la végétation du PNE. Une troisième partie porte son attention sur les évolutions possibles de la végétation sous plusieurs scénarios de changements climatiques et d'utilisation des terres. Les simulations ont montré qu'il est nécessaire de considérer la dynamique temporelle du fait que les conséquences d'un changement climatique peuvent être observées bien après la phase du changement. D'autre part, l'analyse a montré les effets conjugués que peuvent avoir les changements climatiques et la déprise agricole sur la structure de la végétation. Un tel modèle ouvre la voie à l'exploration de multiples scenarios, en permettant non seulement de décrire des paysages futurs potentiels mais aussi les états de transition qui devraient y mener. / On-going global changes have already affected ecosystems and threaten the biodiversity all over the world. In order to maintain the ecosystems services provided to humans and adapt conservation planning, the challenge is to improve our understanding of the mechanisms underlying the maintenance of biodiversity and to predict its response to global changes. In mountainous areas, where the environment is very heterogeneous, the modifications of both climate and land use are expected to strongly influence the landscapes and current biodiversity. This PhD thesis has for main objective to assess the vulnerability of species and habitat to environmental changes in the French Alps. It uses three different approaches and relies on the large databases accumulated by two institutions: the National Alpine Botanical Conservatory and the Ecrins National Park (PNE). The first part of the PhD confronts theoretical hypotheses for species coexistence to observations and describes the characteristics of the regional flora. The species ecological niche breadth has been estimated and related to other rarity facets and trade-off between plant functional strategies. A second analysis disentangles the drivers of the presence or the local abundance of 21 focal species and highlights the importance of the dispersion and the source-sink dynamics. The second part is based on the same conceptual background and aims to develop a dynamic model of the vegetation structure and diversity. The model has been validated for the vegetation of the PNE. The last part proposes an application of this dynamic model to provide multiple biodiversity scenarios in respect to change in both climate and land management. The simulations showed that the consequences of climate change might be visible only after a certain time-lag, demonstrating the interest of considering the spatial but also temporal vegetation dynamics. Furthermore, the analysis pointed out the importance of the interplay effects between climate and land use abandonment. Such a model should pave the way for the exploration of multiples scenarios and will be able to describe not only the potential future landscapes but also the transition states leading to it.
164

Metoder för motverkande av bruteforce-attacker mot Wi-Fi Protected Setup

Forsman, Erik, Skoglund, Andreas January 2012 (has links)
Konfigurationsprotokollet Wi-Fi protected setup (WPS) har vissa brister idess design gällande hur autentiseringen av den PIN-kod som används för attansluta en enhet till ett trådlöst nätverk är implementerad. Dessa brister kanutnyttjas av en attackerare för att utföra en bruteforce-attack som på enrelativt kort tid kan identifiera den korrekta koden. Detta arbete har tagit frammetoder för att motverka eller fördröja attacker mot WPS-protokollet sommed relativt enkla medel kan implementeras i befintliga nätverk. Genomutförda praktiska experiment där en fristående server upptäckt en attack ochgenomfört olika försvarsmetoder har de mekanismer som presenterats utvärderats. Slutsatsen är att den effektivaste metoden för att avbryta en bruteforce-attackmot protokollet är att automatiskt byta ut PIN-koden då en attack upptäcks. / Wi-Fi protected setup (WPS), a protocol used to configure wireless clients, isflawed in regard to the design of the authentication procedure for the PIN-code used to connect a new device. This flaw can be exploited by an attackerto perform a brute force attack to identify the code. This report presentsmethods to counteract brute force attacks performed against the WPS-protocol. The study has been performed by practical experiments where thecountermeasures have been evaluated and their performance has beenmeasured. With simple means, such as a third party acting on the routersbehalf in implementing countermeasures against the attacker, the attack canbe counteracted. The conclusion is that the most effective way of countering the WPS-bruteforce attack presented is to automatically replace the PIN-code with arandomly generated one when an attack is detected.
165

Wireless Protected Setup (WPS) : Prestandajämförelse mellan Reaver och Bully

Alm, Fredrik January 2015 (has links)
Wireless Protected Setup (WPS) är ett säkerhetsprotokoll för trådlösa nätverk. Dess design medför en allvarlig säkerhetsbrist som kan möjliggöra att obehöriga kan få åtkomst till ett lösenordskyddat trådlöst nätverk. Vid attack finns det olika verktyg tillgängliga att använda. I denna rapport jämförs mjukvaruverktygen Reaver och Bully i attack mot WiFi’s WPS-protokoll, där Bullys prestanda tidigare har påvisats vara mer effektiv och förutsätts snabbare utföra brute-forceattack jämfört med Reaver. Ett praktiskt laborationsexperiment har utförts för att undersöka vilken skillnad i hastighet som kan ses mellan verktygen Reaver och Bully i en brute-forceattack. Experimentet utfördes genom att mäta tiden det tog för de två verktygen att testa 100 PIN-nycklar mot en router utan skyddsmekanismer hos WPS. Resultatet visar att Bully utför en brute-forceattack i högre hastighet jämfört med Reaver. Dock, med den högre attackhastigheten som Bully innehar, kan stabilitetsproblem vid attack medföras, vilket öppnar upp för framtida diskussion om högre hastighet bör prioriteras över stabilitet för lyckade attacker. / Wireless Protected Setup (WPS) is a security protocol for wireless networks. Its design contains a serious security flaw that could allow an attacker access to a password-protected wireless network. An attack can be executed using various tools available. In this report, the software-tools Reaver and Bully are compared in performance against WiFi’s WPS-protocol, where Bully previously has been shown to be more effective and predicted faster to execute a bruteforce-attack. A practical laboration has been executed in order to determine differences in speed that can be seen between the tools Reaver and Bully in a bruteforce-attack. The experiment was done by measuring the time it took both tools to test 100 PIN-numbers against a router without protection for WPS. The result shows that Bully performs a bruteforce-attack in higher speed compared to Reaver. However, with the higher attack-speed that Bully uses, some stability issues may follow, opening the topic of future discussion regarding priorities of speed vs. stability for successful attacks.
166

INDICAÇÕES GEOGRÁFICAS NO BRASIL: POSSIBILIDADES PARA OS PRODUTORES INSERIDOS NA ÁREA DE PROTEÇÃO AMBIENTAL DO IBIRAPUITÃ RS / GEOGRAPHICAL INDICATIONS IN BRAZIL: POSSIBILITIES FOR FARMERS IN THE APA OF IBIRAPUITÃ RS

Vargas, Ivens Cristian Silva 15 April 2008 (has links)
Agribusiness is an important sector to contribute the Brazilian trade surplus. The European Union and the United States are among the main destinations of agrofood products, taking part in 31.4% and 14.2% out of the exportations, respectively. The consumers, especially the Europeans, have presented themselves more demanding in what concerns farming products for human consumption, due to the nature of these products and the frequent food crisis. Thus, market segmentation based on information about the origin of the product and production process for differentiation and price attribution has become important, due to the fact that farming systems which are scale-based and linked to the production of commodities have become weakened beyond such markets. In this context, an alternative for development for certain regions is to consider regional/local specificities as factors that determine their identity, based on the concept of geographical indications. This scenario presents an opportunity for the farmers located in the APA of Ibirapuitã. Historically, the region is linked to animal production, due to the fact that the natural pastures there found provide a good support for this type of activity, which has marked the tradition, history and culture of the Gaúcho. The natural environment, therefore, characterises certain intrinsically specific attributes for the products that are originated from it, being that an important aspect in Geographical Indications. Thus, the geographical origin system, used in a Protected Designations of Origin or Protected Geographical Indications approach, is an alternative of development through the territorial perspective. This region is inserted in a conservation area legally known for its peculiar characteristics linked to the Pampa Bioma, which legitimizes extensive animal production. The development of a prototype of a system with a geo-referenced database occurred due to the need of obtaining the position of farmers in relation to the borders of the APA of Ibirapuitã. Finally the geographical indications can be used not only as tools to access other markets, but also for agricultural development, in the sense of valuing territories, mainly for small farmers that are strongly linked to their place of origin, history and culture. This space-time relation values the richness of natural, historical and cultural characteristics, i.e., the features which are fundamental for the differentiation of its production. This approach allows the origin of a product and/or its production processes to be valued, and to convert them into a differentiation and value aggregation factor, besides assuring the products identified according to pre-established parameters in what refers mainly to environmental, social and sanitary issues, as an alternative to the new barriers present in today s economical negotiations. / O agronegócio tem importante contribuição no superávit da balança comercial brasileira. A União Européia e os Estados Unidos estão entre os principais destinos dos produtos agrícolas, com uma participação de 31,4% e 14,2%, respectivamente. Os consumidores, principalmente europeus, têm se mostrado motivados em exigir maior transparência em relação aos produtos agroalimentares, devido à própria natureza destes produtos e às freqüentes crises alimentares. Assim, torna-se importante a segmentação de mercado baseado em informações sobre origem do produto e/ou processo de produção para diferenciação e agregação de valor, pois sistemas agropastoris baseados em escala e vinculados à produção de commodities se enfraqueceram frente a estes mercados. Dentro deste contexto, uma alternativa de desenvolvimento para certas regiões é considerar especificidades regionais/locais do território como determinantes de sua identidade, base do conceito de indicações geográficas. Este cenário possibilita uma oportunidade para os produtores localizados na APA do Ibirapuitã, historicamente a região está vinculada à pecuária, decorrente do suporte dos campos naturais ao desenvolvimento desta atividade, que marcou a tradição, história e cultura do gaúcho. O meio natural, portanto, caracteriza atributos intrínsecos específicos para produtos provenientes deste, sendo um aspecto importante nas Indicações Geográficas. Deste modo, o sistema de indicações geográficas, seja utilizando uma abordagem de Indicação de Procedência ou Denominação de Origem, é uma alternativa de desenvolvimento pela perspectiva territorial da região. A mesma está inserida numa unidade de conservação reconhecida legalmente por suas características pecualiares vinculadas à localização no Bioma Pampa, o que legitima a atividade de produção animal extensiva. O desenvolvimento do protótipo de um sistema com uma base de dados georreferenciada ocorreu pela necessidade de obtenção, neste primeiro momento, da localização dos produtores em relação aos limites APA do Ibirapuitã e de dados sobre recursos sócio-econômicos, objetivando obter um conhecimento prévio da área em estudo. A extensão geográfica - característica da área - associada à complexidade e diversidade de características dos sistemas agrários requer, sempre que possível, o uso de instrumentos e tecnologias disponíveis ao levantamento e análise de informações, processo que pode ser facilitado com a utilização de imagens de satélites, aplicação de fichas de levantamento adequadas à região e pelo uso de técnicas estatísticas para o tratamento dos dados. Analisando sobre estes aspectos, os resultados preliminares do protótipo desenvolvido foram adequados aos objetivos propostos, pois possibilitou a facilidade de armazenamento e obtenção de resultados baseados na análise dos dados, além da facilidade de localização destes produtores em relação aos limites desta unidade de conservação. Finalmente, as indicações geográficas podem ser utilizadas, não apenas como instrumentos para acesso a mercados, mas também como uma ferramenta de desenvolvimento rural, no sentido da valorização dos territórios, principalmente para os pequenos produtores que possuem forte vinculação com o local de origem, história e cultura. Esta relação espaço-tempo oferece a riqueza de seu patrimônio natural e histórico-cultural, ou seja, sua tipicidade fundamental à diferenciação de sua produção. Esta abordagem permite proteger e valorizar a origem de um produto e/ou processos de produção, e convertê-las em fator de diferenciação e agregação de valor, além de garantir produtos identificados de acordo com parâmetros pré-estabelecidos no que se refere principalmente a questões ambientais, sociais e sanitárias, alternativa às novas barreiras presentes nas atuais negociações econômicas.
167

Governing Change and Adaptation at Pacific Rim National Park Reserve (Canada) and Saadani National Park (Tanzania)

Orozco-Quintero, Alejandra 18 January 2016 (has links)
In what can be characterized as a period of rapid ecological change, the global community has now reached an agreement on the importance of protecting what remains of the world’s biological diversity. In 2011, world governments pledged to extend protected areas (PAs) to 17% of the earth’s surface. Although, accumulated research documents the role PAs areas play in coping with environmental change, much of conservation practice remains at odds with the actual purpose of conservation: to enable natural and human systems to adapt and sustain life. Challenges in PA planning and management, and their connections (or lack thereof) to wider socio-economic and institutional frameworks have made environmental governance a leading concern in the study of PAs. This research examined the nature and dimensions of environmental governance affecting adaptive capacity and the sustainability of protected landscapes, particularly for PAs deemed to have been established and/or operating through ‘participatory’ governance. These issues are explored through comparative research based on case studies of two coastal PAs: Pacific Rim National Park Reserve in Canada, and Saadani National Park in Tanzania. Methods utilized included gathering qualitative and spatial data through interactions with decision-making bodies and representatives of agencies at the village/First Nations and park levels, interviews with state authorities at district and higher levels and document research. The research findings on the two PAs and adjacent communities unravel the nature and dynamics of steering institutions, institutional interplay and spatial interconnectedness as they relate to cooperation, agency and adaptability within and around protected landscapes. An examination of spatial and institutional arrangements within national frameworks, and an examination of governance and management practice at the level of individual parks reveal significant mismatches between policy discourses on multi-level cooperation and actual practice in state-based conservation. This research also reveals ways in which sustainability can be conceived and addressed through institutions and institutional interplay among park and community actors. The research analyzed ways in which encompassing frameworks shaped institutions, relationships and activities on the ground, and spatial interconnectedness and interdependence shaped the actions and agency of grassroots actors. The findings also demonstrate that there are critical differences between participation and the exercising of agency. While it is important to achieve a fair distribution of burdens and benefits across levels, it is shared jurisdiction and fair institutional interplay, rather than economic benefits, which can better enable all levels of social organizations to contribute to sustainability. In this regard, enhancing agency is essential to enabling adaptability and goes beyond addressing disruptive power relations; it also entails redefining perceptions of human nature and of spatial interconnectedness among communities and natural landscapes in the design of environmental institutions. It is through institutionally-driven processes, such as giving full political and financial support to states fixed on gaining spatial control of culturally diverse landscapes through restrictive conservation approaches, that conservation has become an instrument of oppression, and it is only through institutionally-driven means that acknowledge the importance and role of indigenous approaches to preserve ecological diversity that PAs can be made to serve their purpose: to preserve nature and cultural heritage for present and future generations. / Graduate / 0534 / 0366 / aleja@uvic.ca
168

Challenges of Wireless Security in the Healthcare Field : A study on the WPA3 standard

Mironov, Georgiana January 2020 (has links)
The healthcare environment is a complex one, saturated by wireless medical devices and sensitive patient data flowing through the network traffic. With the increased popularity of wireless medical devices in the healthcare domain together with the announcement of the new wireless security standard WPA3 comes a need to prepare for a new generation shift in wireless security. The goal of this study is therefore to investigate what challenges the healthcare sector can encounter when faced with the inevitable transition to WPA3. By performing a literature review on the security state of WPA3 compared to its predecessor and performing qualitative interviews with network technicians working in the healthcare sector, three major challenges were identified. IT professionals in the healthcare domain struggle with integrating legacy software systems, keeping middleware software solutions secure, and with handling hardware medical devices that come with outdated wireless standards. By analysing existing literature, several mitigating actions to battle these challenges were presented in this study.
169

Skyddade områden i Kalmar län - utveckling och resiliens / Protected areas in Kalmar County - development and resilience

Turesson, Anette January 2016 (has links)
The biological diversity of the world has decreased. Sweden has ratified the UN Convention "Convention on Biological Diversity" which aims to increase biodiversity. Formally protected areas in Sweden are national park, national reserve, habitat area and conservation area. Kalmar County follows the national targets where one of the goals is to increase the proportion of protected areas to 20 % of the land area by the year 2020. Climate change is an added stress factor for different species and is seen as one of the most serious threats to biodiversity. To explore the development of formally protected areas in Kalmar County over a period of 20 Years, from 1994 to 2014, the number of areas, its acreage, variability and connectivity has been investigated for the years 1994, 2000, 2005, 2010 and 2014. Analyses have been made of the findings in relation to goals made by the government, current research and the impact of climate change. Facts have been found in literature on the subject and by GIS analysis. The results show that the number of and the acreage of protected areas has increased. The proportion of protected land in Kalmar County during the period increased from 0.65 % to 2.3 %. According to the goals of the government and research on the subject regarding climate change, this is far too low. The variability of habitat has also increased, but according to research and the goals of the government are the different areas too small. An assessment is that the core areas should be on 250 hectares, wich only 5 % of the areas in the County of Kalmar were. The distance between formally protected areas has decreased and the proportion of areas that had direct contact has increased from none to 21.9 % in 2014. Because of insufficient facts and of the big importance of the protected areas surrounding environment, no conclusions can be drawn for connectivity in this study.
170

Species assembly patterns and protected area effectiveness in times of change : a focus on African avifauna

Coetzee, Bernard Walter Thomas 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The challenge of conserving biodiversity is daunting. Despite some local conservation gains, most indicators of the condition of global biodiversity show declines since the 1970’s, while indicators of the threats to biodiversity all show increases. Humanity has in part responded to the global biodiversity extinction crisis by establishing protected areas (PA) and they are widely considered cornerstones of conservation. However, their efficacy in maintaining biodiversity is much debated. Previous studies have been unable to provide a general answer because of their typically restricted geographic and/or taxonomic focus, or qualitative approach. Using a global meta-analysis with 861 pairwise comparisons inside and outside PAs from 86 studies across five major taxon groups, I tested the hypothesis that PAs achieve significant conservation outcomes measured as higher biodiversity values compared with alternative land covers. I found that globally, PAs typically contain higher abundances of individual species, higher assemblage abundances and higher species richness. Variation in effect sizes among taxa nonetheless underscores that PA efficacy can be context specific. To examine factors driving the context specific nature of PA efficacy, an exact distance, timed point count methodology was used to assess PAs ecological effectiveness in terms of bird assemblages of the Kruger National Park (KNP), South Africa, in the Phalaborwa section. Bird assemblages inside the KNP were compared to matched sites in rural and urban land cover, as well as the connecting habitat matrix outside the KNP. Species richness and abundance were significantly lower inside the KNP compared to other land covers. However, the species assemblages are markedly different. The artificial addition of resources in an otherwise resources poor area, mainly in terms of gardening, provide suitable habitat for a range of species, consistent with the more individuals hypothesis. Large-bodied and ground nesting species are virtually absent outside the KNP. Thus species richness and abundance differences between land cover regions mask insidious changes in species traits. Nonetheless, not formally protected land can contribute positively to the regional biodiversity portfolio. Since an understanding of the mechanisms that structure species assemblages can aid in the consequences of anthropogenic drivers disentangling them, I describe and analyse the body size frequency distributions (BSFDs) of avian assemblages at several spatial scales in the Afrotropical biogeographic realm. I found that the African avifaunal continental BSFD is unimodal and right-skewed. African avifaunal BSFDs are quantitatively dissimilar to the African mammal BSFDs, which are bimodal at all spatial scales. Much of the change in median body size with spatial scale can be captured by a range-weighted null model, suggesting that differential turnover between smaller- and larger-bodied species might explain the shift in the central tendency of the BSFD. My results for the first time quantitatively demonstrate that PAs are a vital component of a global biodiversity conservation strategy. However, I also show that PA ecological effectiveness can be context specific, and understanding which species traits are at risk outside of PAs is critical to predicting their efficacy. / AFRIKAANSE OPSOMMING: Dit is ‘n uitnemende uitdaging om biodiversiteit te bewaar. Ten spyte van sommige sukses op ‘n lokale skaal, dui die meeste indikators aan dat die toestand van globale biodiveristeit afgeneem het vanaf die 1970’s, terwyl bedreigings daartoe toegeneem het. Die mensdom het gedeeltelik reageer op die biodiversiteits uitsterfings krisis deur die uiteensetting en instandhouding van bewaringsgebiede (BG). Hierdie metodiek word wêreldwyd geag as ‘n hoeksteen van bewaring. Die ekologiese doeltreffendheid van BG word egter baie debateer. Vorige studies was geografies beperk of het net op sekere takson groepe gefokus. Vorige studies is ook tipies statisties kwalitatief van aard. As gevolg daarvan het ek ‘n globale meta-analiese gebruik, wat bestaan het uit 861 gepaarde meetings vanaf 86 studies, oor vyf verskillende taksonomiese groepe. Ek het die hipotese getoets dat BG statisties beduidende bewaring laat gekiet in terme van hoër biodiveristeits waardes binnekant hul grense, in kontras met areas buite BG. Ek het gevind dat BG juis hoër waardes van hoër indivuduele spesies hoeveelhede, gemeenskaps hoeveelhede en spesiesrykheid bevat. Tog dui die variasie in effek grootte onder takson groepe aan dat BG effektiwiteit konteks spesifiek is. Aangesien BG effektiwiteit konteks spesifiek is, het ek verder ‘n tydstip, eksakte-afstand punttelling metodiek gevolg om die Kruger Nationale Park (KNP) in Suid Afrika, se ekologiese doeltreffendheid te bepaal. Ek het voëlgemeenskappe binne KNP vergelyk met voëlgemeenskappe buite KNP. Metings is buite die KNP gedoen in tuislande, die stadsgebied van Phalaborwa, asook in die habitat matriks wat die areas verbind. Beide spesiesrykheid en hoeveelheid is hoër buite KNP, maar die voëlgemeenskap struktuur tussen gebiede verskil noemenswaardig. Die uitbreiding van bronne ten opstigte van nesmaak en voeding (meestal deur tuinmaak), bied vir voëls goeie habitat in die stadsgebied, soos verwag kan word uit die meer individue hipotese. Hierdie veranderinge in spesiesrykheid tussen die verskillende areas versteek veranderinge in die spesies einskappe. Voëls met groot liggaamsmassa, veral die wat op die grond nes maak, kom in baie minder getalle voor buite KNP. Tog bied onbewaarde areas ‘n positiewe inpak tot die omgewing se biodiversiteit. ‘n Holistiese begrip van die meganismes wat spesies gemeenskappe struktureer kan help om die menslike invloed daarop uit te lig. Daarvolgens beskryf ek die liggaamsmassa frekwensie verspreiding (LMFV) oor verkillende skale in die Afrotropies biografiese streek. Ek het bevind dat Afrika se voëlgemeenskappe op die kontinentale skaal unimodaal en regs-geskewe is. Afrika se voël LMFV is beduidend verskillend van Afrika soogdier LMFV, wat bimodaal is op verskeie skale. Baie van die verandering in mediaan liggaams massa oor verskillende skale kan verduidelik word met ‘n verspreidings-aangepaste nul-model, wat voorstel dat die verskille in omset van voëls met of klein, of groot liggaamsmassa in die landskap die veranderings in LMFV verduidelik. My studie is die eerste van sy soort wat kwantitatief bepaal dat die gebruik van BG krities is tot ‘n globale bewaringsstrategie. Verder het ek bewys dat BG se ekologiese doeltreffendheid afhang van die kontkes op ‘n lokale skaal, en dat spesies eienskappe geïnkorporeer moet word om BG se doeltreffendheid te bepaal.

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