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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.
361

Ecogovernamentalidade e meio ambiente urbano: uma análise sobre o Plano Diretor de Resíduos Sólidos da Região Metropolitana da Grande Vitória

Mozine, Augusto Cesar Salomão 03 October 2014 (has links)
Made available in DSpace on 2016-04-26T14:55:04Z (GMT). No. of bitstreams: 1 Augusto Cesar Salomao Mozine.pdf: 5355782 bytes, checksum: b4302d9bf705c2fc24768d098c9f41d4 (MD5) Previous issue date: 2014-10-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This tesis aims to outline Brazilian society participation in the formulation of the National Policy on Solid Waste in light of the Master Plan for Solid Waste in the Metropolitan Region of Grande Vitória. It analyses the documents related to this Policy formulation provided by Brazilian Parliament in other to extract from them the political and social discourse used by different actors that intervened in the legislative processes. The main issue that is brought in this paper is how social participation was considered on this policy formulation giving legitimacy to the political processes. In a first glance, it s important to provide a historical perspective of solid waste management in Brazilian society. Then, it s relevant to show how this discussion is related with Brazilian constitutional aims and how it affects politics in a federative system, considering social participation and accountability in this process / Objetiva discutir a participação social na formulação da Política Nacional de Resíduos Sólidos diante de Plano Diretor de Resíduos Sólidos da Região Metropolitana da Grande Vitória. Propõe uma discussão baseada na ecologia política do processo legislativo brasileiro e sua relação com a ação social com vistas ao controle ambiental da questão dos resíduos sólidos urbanos. Dessa maneira, parte da premissa de que a ausência de entendimento é, hoje, uma constante na política brasileira. A falta de prática da Política no espaço público nacional tem contribuído a um excesso de regulamentação da vida privada, sob pretextos alarmistas ou salvacionistas e, não raro, sob ambos. Há, sim, uma ênfase na necessidade de que o Brasil atue frente ao problema da gestão do lixo urbano através da criação, implementação e expansão de mecanismos regulatórios de metas de tratamento de resíduos, sempre ressaltando que isso deve ocorrer provocando uma mudança no sistema produtivo, na forma de ordenamento das relações sociais por meio do aprimoramento da tecnologia, sem, contudo, prever qualquer debate social amplamente difundido para tratar como isso pode ser realizado
362

Estudo de dois métodos de amostragem para inventário da arborização de ruas dos bairros da orla marítima do município de Santos, SP. / Study of two sampling methods employed for the street tree inventory in the coastal neighbourhoods of the city of Santos, in the state of São Paulo, Brazil.

Meneghetti, Gabriela Ignarra Pedreira 07 October 2003 (has links)
Este estudo teve como objetivo verificar a eficiência de dois métodos de amostragem de árvores de rua para os bairros da orla marítima da cidade de Santos. Foram empregadas a amostragem sistemática simples e a amostragem estratificada por bairros. Cinco estratos corresponderam aos bairros Ponta da Praia, Aparecida, Embaré, Boqueirão, e, o último, denominado Composto, compreendeu três bairros vizinhos, o Gonzaga, o Pompéia e o José Menino. Dos 470 quarteirões não compostos integralmente por áreas verdes e localizados na área de estudo, foram selecionados 70 para compor a amostra (14,9%) tanto da amostragem sistemática simples quanto da amostragem estratificada. A fim de estimar o parâmetro populacional que representa a abundância de árvores, utilizou-se a variável "número de árvores por quilômetro de calçada". Foi realizado um inventário qualitativo e quantitativo no qual foram anotados o perímetro dos quarteirões (incluindo as calçadas), o número de elementos existentes (árvores e arbustos vivos ou mortos) e suas características. Os dois métodos de amostragem foram eficientes para o levantamento de árvores de ruas nos bairros da orla marítima da cidade de Santos, mas deu-se preferência para a amostragem sistemática simples, uma vez que o ganho em precisão obtido através da estratificação por bairros foi muito pequeno. Para avaliar a riqueza e a abundância das espécies e as diferenças na composição de espécies dos estratos foram calculados os índices de diversidade de Shannon e de Jaccard. As sete espécies mais freqüentes foram Inga laurina (ingá), Sapindus saponaria (saboneteira), Terminalia catappa (chapéu-de-sol), Ficus benjamina (figueira-benjamin), Delonix regia (flamboyant), Lagerstroemia indica (resedá ou extremosa) e Callophyllum brasiliensis (guanandí). De cada um dos 1282 elementos vivos avaliados foram levantadas características relacionadas ao tamanho das árvores, ao tipo de condução ou poda, à qualidade da copa e do tronco, à fitossanidade, à compatibilidade com o local de plantio, à área livre de pavimentação, aos danos aos passeios e à presença de redes aéreas e de obstáculos ao desenvolvimento das plantas. / The aim of the present study is to examine the efficiency of two sampling methods for street trees inventory in the coastal neighborhoods of the city of Santos. Two methods have been employed: the simple systematic sampling and the stratification according to neighborhood. The five strata which have been analyzed correspond to the following neighborhoods: Ponta da Praia, Aparecida, Embaré, Boqueirão and one strata hereby called Compound, which actually comprehends three adjacent neighborhoods, namely Gonzaga, Pompéia and José Menino. Of the 470 blocks not entirely made up of green areas witch still situated in the study area, 70 have been selected to be the sample (14.9%), in the simple systematic method as well as in the stratified type. In order to estimate the population parameter representing the abundance of trees, the variable "number of trees per kilometer of sidewalk" has been utilized. A qualitative as well as a quantitative inventory has been drawn up in which we have annotated the perimeter of the blocks (sidewalks included), the number of existing elements (trees, bushes and shrubs, either dead or living) and their characteristics. Although both methods of sampling have proven to be efficient for street trees inventories in the coastal neighborhoods of the city of Santos, we have given preference to the simple systematic sampling type, since very little gain in accuracy has been obtained from the sampling method of stratification by neighborhood. So as to estimate the wealth and abundance of the species and the differences in the species composition between the five strata, we have calculated both Shannon and Jaccard diversity indexes. The seven most frequent species are the following ones: Inga laurina (ingá), Sapindus saponaria (saboneteira), Terminalia catappa (chapéu-de-sol), Ficus benjamina (figueira-benjamin), Delonix regia (flamboyant), Lagerstroemia indica (resedá or extremosa) and Callophyllum brasiliensis (guanandí). Of each of the 1.282 evaluated living elements, we have registered characteristics related to the following aspects: tree size, type of conduction or pruning, quality of crown and trunk, insect or disease problems, degree of compatibility with the planted site, areas devoid of paving, damage caused to pavements and the presence of wiring and cables or any obstacles to plant development.
363

The Ma(r)king of memory and the right to remember: design, interpretation and the movement of meaning. An investigation into the role of design in shaping Euro-Western experience and interpretation of the post genocide memoryscapes of Cambodia and Rwanda

Davis, Shannon January 2009 (has links)
Bearing witness to tragedy, the aftermath of genocide often resides quite evidently within the landscape. A potent container of memories and representation, the landscape provides both a symbolic role in which to honour the victims and give survivors a place to mourn and remember, but is also often infused with the tensions of post-genocide life. The memoryscapes of the Cambodian and Rwandan genocides illustrate these contested concerns explicitly. The case study sites investigated in this study - the Tuol Sleng Genocide Museum and the Choeung Ek Genocidal Centre in Cambodia, and the Kigali Memorial Centre in Rwanda - each express today (consciously or unconsciously) design strategies that engage the Euro-Western visitor. Termed Euro-Western ‘cues to connect’, encountered and existential phenomenological data is analysed in relation to design interpretation and the affective cognition of meaning. Finally, considered in relation to Berlin’s Memorial to the Murdered Jews of Europe, post genocide memorialisation is analysed in its ability to connect through time and culture - through its ability to transpose interpretations and evolve as the needs of society change.
364

以風環境與熱環境觀點模擬社區規劃之適宜性- 台北市健康社區為例 / CFD Simulation of The Suitability of Jian-Kang Community from The Perspective of Thermal and Wind Environment

陳建宏, Chen, Chien Hung Unknown Date (has links)
林憲德等人於1999年提出台北夏季午夜之都市熱島強度為4.5℃,至2012年簡子翔等人所提出夏季白天最大熱島強度6.18℃、午夜4.38℃,可以發現台北市的高溫化現象並未有顯著的差異,甚至還新增加了多個新興熱區。 本研究以健康新城為研究對象,以實測方式、CFD電腦模擬方法,釐清社區建築環繞下,社區內的高溫化現象,並與社區外的街道環境比較溫度差異,評估熱舒適性。研究結果顯示,建築環繞下的社區內部(社區中庭),在日落後的確有高溫化現象,白天時則會因為各社區的遮蔽條件、綠化條件不同,而有不同程度的差別。而模擬結果亦顯示,社區開口條件、通風道配置不同,也會影響社區中庭與外部周邊街道環境之舒適性差異。 建議未來社區的建築規劃設計,除了增加綠化措施之外,尚能適度增加開放空間,增加通風性能;而公部門在訂定法定容積時,應考量都市環境因素(增加遮蔽、通風),酌以調整已達優良的都市實質環境。 / According to Urban Heat Island’s studies by Lin et al. (1999) and Chien et al. (2012), urban heat island intensity (UHIs) of Taipei didn’t get an obvious improvement from 1999 to 2012. UHIs of Taipei was 4.5℃ in the midnight in 1999, 4.38℃ in the midnight in 2012 and 6.18℃ in the daytimes in 2012. Obviously, there are several high temperature area appeared in the years. This study tries to measure the thermal comfort between the area inside Jian-Kang community and the streets’ environment around Jian-Kang community. Furthermore, this study utilize CFD simulation that can help the study knows the reason effects thermal comfort. As the result of the study, the area inside Jian-Kang community has higher temperature after sunset. In the morning, it will have difference due to the shadow and green situation. Also, the simulation results show that the draft condition of the community will influence the thermal comfort. In the future, this study suggests some strategy to have a better urban environment. First, increase much more greening measures. Second, preserve open spaces to improve the ventilation when deciding the community’s design. Third, consider the urban environmental factors when rule the building’s height.
365

都市環境管理における官民パートナーシップと効率性に関するアジア比較研究

白川, 博章, 金子, 慎治 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(C) 課題番号:17510035 研究代表者:白川 博章 研究期間:2005-2006年度
366

Bayesian Approach for Reliable GNSS-based Vehicle Localization in Urban Areas / Zuverlässige satellitengestützte Fahrzeuglokalisierung in städtischen Gebieten

Obst, Marcus 20 March 2015 (has links) (PDF)
Nowadays, satellite-based localization is a well-established technical solution to support several navigation tasks in daily life. Besides the application inside of portable devices, satellite-based positioning is used for in-vehicle navigation systems as well. Moreover, due to its global coverage and the availability of inexpensive receiver hardware it is an appealing technology for numerous applications in the area of Intelligent Transportation Systems (ITSs). However, it has to be admitted that most of the aforementioned examples either rely on modest accuracy requirements or are not sensitive to temporary integrity violations. Although technical concepts of Advanced Driver Assistance Systems (ADASs) based on Global Navigation Satellite Systems (GNSSs) have been successfully demonstrated under open sky conditions, practice reveals that such systems suffer from degraded satellite signal quality when put into urban areas. Thus, the main research objective of this thesis is to provide a reliable vehicle positioning concept which can be used in urban areas without the aforementioned limitations. Therefore, an integrated probabilistic approach which preforms fault detection & exclusion, localization and multi-sensor data fusion within one unified Bayesian framework is proposed. From an algorithmic perspective, the presented concept is based on a probabilistic data association technique with explicit handling of outlier measurements as present in urban areas. By that approach, the accuracy, integrity and availability are improved at the same time, that is, a consistent positioning solution is provided. In addition, a comprehensive and in-depth analysis of typical errors in urban areas within the pseudorange domain is performed. Based on this analysis, probabilistic models are proposed and later on used to facilitate the positioning algorithm. Moreover, the presented concept clearly targets towards mass-market applications based on low-cost receivers and hence aims to replace costly sensors by smart algorithms. The benefits of these theoretical contributions are implemented and demonstrated on the example of a real-time vehicle positioning prototype as used inside of the European research project GAlileo Interactive driviNg (GAIN). This work describes all necessary parts of this system including GNSS signal processing, fault detection and multi-sensor data fusion within one processing chain. Finally, the performance and benefits of the proposed concept are examined and validated both with simulated and comprehensive real-world sensor data from numerous test drives.
367

Biodiversidade como tema para a educação ambiental : contextos urbanos, sentidos atribuídos e possibilidades na perspectiva de uma educação ambiental crítica

Thiemann, Flávia Torreão Corrêa da Silva 20 March 2013 (has links)
Made available in DSpace on 2016-06-02T19:29:56Z (GMT). No. of bitstreams: 1 5129.pdf: 1704174 bytes, checksum: cf67946242d496e698e4fa00a29c2344 (MD5) Previous issue date: 2013-03-20 / Universidade Federal de Sao Carlos / Biodiversity is all around us, in what we wear, eat, into objects from our daily, past and future lives. It is present as an explosion of colors and hues, sounds and smells. It is both invisible and inescapable. The discourses on biodiversity are also multiple: it is the basis of life on Earth, it is essential, and yet suffers constant threats. In this thesis we seek to raise possibilities of working with biodiversity as a theme in an urban environment, the São Carlos Ecological Pole, and to understand the meanings attributed to biodiversity by researchers and students in the Life Sciences and similar areas, and to envision possibilities for addressing the concept of biodiversity in environmental education processes conducted within the principles of a critical environmental education. We conducted a qualitative study, using naturalist research techniques and the Delphi Method, and used a philosophical hermeneutics perspective to interpret and understand the data. This research generated nine categories of meaning attributed to biodiversity: Concreteness, Symbolic, Knowledge, Holism, Kaleidoscope, Hidden, Threatened, Inclusive and Exclusive, listed 16 sets of concepts considered essential, organized in spheres that contemplate aspects of scientific content, values and action, and six suggestions of themes that can help the process of learning about biodiversity: Experiencing biodiversity; "Opening your eyes" for biodiversity; Exercising dialogue/discussions; Acknowledging the importance of biodiversity and the limits of human interference; Biodiversity in our own territory; Overcoming teaching fragmentation. The results are ideas, suggestions, possibilities to be explored from the perspective of a critical environmental education, and must be contextualized in processes that respect the multiplicity of views on environmental issues, and seek understanding and to build agreements that allow for action in favor of the diversity of life on Earth. / A biodiversidade está em tudo ao nosso redor, no que vestimos, comemos, em objetos de nosso cotidiano, passado e futuro. Faz-se presente como uma explosão de cores e tons, de sons e aromas. É ao mesmo tempo invisível e inescapável. Os discursos sobre a biodiversidade também são múltiplos: ela é a base da vida na Terra, é essencial, e, no entanto, sofre ameaça constante. Nesta tese buscamos levantar possibilidades de trabalho com o tema da biodiversidade em um ambiente urbano, o Polo Ecológico de São Carlos e entender quais são os sentidos atribuídos à biodiversidade por pesquisadoras/es e estudantes da área de Ciências Biológicas e afins, e as possibilidades de trabalhar com o conceito da biodiversidade em processos educativos conduzidos dentro dos princípios de uma educação ambiental crítica. Realizamos uma pesquisa qualitativa, com o uso de técnicas de pesquisa naturalista e do Método Delphi, e utilizamos o referencial da hermenêutica filosófica na interpretação e compreensão dos dados. Na pesquisa foram geradas nove categorias de sentido atribuído à biodiversidade: Concretude, Simbólico, Conhecimento, Holismo, Caleidoscópio, Oculta, Ameaçada, Inclusiva e Exclusiva, elencados 16 conjuntos de conceitos considerados essenciais, organizados em esferas que contemplam aspectos de conteúdos científicos, valores e atuação, e seis sugestões de temas que podem auxiliar o processo de aprendizagem sobre a biodiversidade: Experimentar a biodiversidade; Abrir os olhos para a biodiversidade; Exercitar diálogo/debates; Perceber a importância da biodiversidade e os limites da interferência humana; Biodiversidade no próprio território; Superação da fragmentação do ensino. Os resultados são ideias, sugestões, possibilidades a serem exploradas, sob a perspectiva da educação ambiental crítica, e devem ser contextualizadas em processos que respeitam a multiplicidade de olhares sobre a questão ambiental e buscam a compreensão e a construção de acordos que permitam a ação em prol da diversidade de vida do planeta.
368

Understanding and exploiting mobility in wireless networks / Comprendre et exploiter la mobilité dans les réseaux sans fil

Uppoor, Sandesh 29 November 2013 (has links)
Le degré de pénétration du marché des appareils intelligents tels que les smartphones et les tablettes avec les technologies de communication embarquées comme le WiFi, 3G et LTE a explosé en moins d’une décennie. En complément de cette tendance technologique, les applications des réseaux sociaux ont virtuellement connectées une grande partie de la popula- tion, en génerant une demande croissante de trafic de données vers et depuis l’infrastructure de communication. Les communications pervasives ont aussi acquis une importance dans l’industrie automobile. L’émergence d’une gamme impressionnante d’appareils intelligents dans les véhicules a permis des services tels que : l’assistante au conducteur, l’infotainment, le suivi à distance du véhicule, et la connectivité aux réseaux sociaux même en déplacement La demande exponentielle de connectivité a encore défié les fournisseurs de services de télé- communications pour répondre aux attentes des utilisateurs.L’objectif de cette thèse est de modéliser et comprendre la mobilité dynamique des utilisateurs à grande vitesse et leurs effets sur les architectures de réseau sans fil. Compte tenu de l’ importance du développement de notre étude sur une représentation réal- iste de la mobilité des véhicules, nous étudions tout d’abord les approches les plus populaires pour la génération de trafic routier synthétique et discutons les caractéristiques des ensem- bles de données accessibles au public qui décrivent des mobilités véhiculaires. En utilisant l’information des déplacements de la population dans une région métropolitaine, les données détaillées du réseau routier et les modèles réalistes des conduites microscopiques, nous pro- posons un jeu de données de mobilité véhiculaire original qui redéfinit l’état de l’art et qui replie la circulation routière de façon réaliste dans le temps et dans l’espace. Nous étudions ensuite l’impact des dynamiques des mobilité du point de vue de la couverture cellulaire en présence d’un déploiement réel des stations de base. En outre, en examinant les effets de la mobilité des véhicules sur les réseaux autonomes, nous voyons des possibilités pour les futurs paradigmes de réseaux hétérogènes. Motivés par l’évolution dynamique dans le temps, de la mobilité des véhicules observée dans notre jeux de données, nous proposons également une approche en ligne pour prédire les flux de trafic macroscopiques. Nous analysons les paramètres affectant la prédiction de la mobilité en milieu urbain. Nous dévoilons quand et où la gestion des ressources réseaux est la plus cruciale pour accueillir le trafic généré par les utilisateurs à bord. Ces études révèlent de multiples opportunités de gestion intelligente des transports, soit pour construire de nouvelles routes, soit pour l’installation de bornes de recharge électriques, ou pour la conception de systèmes de feux de circulation intelligents, contribuant ainsi à la planification urbaine. / The market penetration of smart devices like smartphones and tablets with embedded communication technologies like WiFi, 3G and LTE has exploded in less than a decade. Complementing this technological trend, social networking applications have virtually connected a large portion of the population generating an ever-growing data traffic demand on the communication infrastructure. Pervasive communications have gained significance in the automobile industry as well, with the emergence of an impressive range of in-vehicle smart devices enabling driver assistance, infotainment, over-the-air vehicle monitoring, and even social connectivity on the move. This surge in the demand for connectivity has further challenged telecommunication service providers to meet the expectations of high-speed network users. The goal of this thesis is to model and understand the mobility dynamics of high-speed users and their effect on wireless network architectures. Given the importance of developing our study on a realistic representation of vehicular mobility, we first survey the most popular approaches for the generation of synthetic road traffic and discuss the features of publicly available vehicular mobility datasets. Using original travel demand information of the population of a metropolitan area, detailed road network data and realistic microscopic driving models, we propose a novel state-of-art vehicular mobility dataset that closely mimics the real-world road traffic dynamics in both time and space. We then study the impact of such mobility dynamics from the perspective of wireless cellular network architecture in presence of a real-world base station deployment. In addition, by discussing the effects of vehicular mobility on autonomous network architecture, we hint at the opportunities for future heterogenous network paradigms. Motivated by the time-evolving mobility dynamics observed in our original dataset, we also propose an online approach to predict near-future macroscopic traffic flows. We analyze the parameters affecting the mobility prediction in an urban environment and unveil when and where network resource management is more crucial to accommodate the traffic generated by users onboard. Such studies unveil multiple opportunities in transportation management either for building new roads, installing electric charging points, or for designing intelligent traffic light systems, thereby contributing to urban planning.
369

Métodos de visão computacional aplicados a extração de características de ambientes urbanos em imagens de satélite de baixa resolução / Computer vision methods applied to extraction of characteristics of urban environments in low resolution satellite imagery

Almeida, Dyego de Oliveira 03 October 2018 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2018-11-05T18:46:12Z No. of bitstreams: 2 Dissertação - Dyego Oliveira Almeida - 2018.pdf: 32110237 bytes, checksum: 4d30b2227be666802bbb2e5437450fc2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-06T10:03:22Z (GMT) No. of bitstreams: 2 Dissertação - Dyego Oliveira Almeida - 2018.pdf: 32110237 bytes, checksum: 4d30b2227be666802bbb2e5437450fc2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-06T10:03:22Z (GMT). No. of bitstreams: 2 Dissertação - Dyego Oliveira Almeida - 2018.pdf: 32110237 bytes, checksum: 4d30b2227be666802bbb2e5437450fc2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-10-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The urban growth of the population and the deforestation of greenareas are one of the most critical problems currently in Brazil. Due to mobilization of rural people to the urban, high solar irradiation and the deforestation, the Government is creating sustainable actions sustainable in order to enlarge the green areas and permeable. In this perspective, to promote this mapping effectively in large areas necessary to the use of technologies of recognition of facial features. Low-resolution satellite imagery have low cost and great coverage area coverage, and therefore apply them in identifying features is advantageous over other types of images. However, to accomplish this identification is computationally complex due to the different features present in images of this type. This work proposes an effective method of digital processing of low resolution images in the identification of features, in particular the pertinent green aáreas with average accuracy of 80.5% and detection of buildings with an average accuracy of 63%. / O crescimento urbano da população e o desmatamento de áreas verdes são um dos problemas mais críticos atualmente no Brasil. Devido a mobilização da população rural para o âmbito urbano, elevação da irradiação solar e o desmatamento, o governo está criando ações sustentáveis a fim de ampliar as áreas verdes e permeáveis. Nesta perspectiva, para promover esse mapeamento de forma eficaz em grandes áreas se faz necessário o uso de tecnologias de reconhecimento de feições. Imagens de satélite de baixa resolução possuem baixo custo e grande abrangência de área, e portanto aplicá-las na identificação de feições é vantajoso em relação a outros tipos de imagens. No entanto, realizar essa identificação é computacionalmente complexo devido as diferentes características existentes em imagens desse tipo. Este trabalho propõe um método eficaz de processamento digital de imagens de baixa resolução na identificação de feições, em particular as pertinentes a áreas verdes com acurácia média de 80,5% e detecção de edificações com precisão média de 63%.
370

Impacto de cães (Canis familiaris) e gatos (Felis catus) errantes sobre a fauna silvestre em ambiente peri-urbano. / Impact of free-ranging dogs (Canis familiaris) and cats (Felis catus) on wildlife in a suburban area.

Claudia Bueno de Campos 17 December 2004 (has links)
Os objetivos deste estudo foram quantificar a população de cães (Canis familiaris) e gatos (Felis catus) errantes em ambiente peri-urbano representado pelo Campus “Luiz de Queiroz” da Universidade de São Paulo, em Piracicaba, SP; descrever e comparar qualitativa e quantitativamente a dieta das duas espécies e estimar sua pressão de predação sobre as espécies silvestres de mamíferos. Durante os meses de julho de 2002 e janeiro de 2003, foram realizadas observações visuais e coletadas amostras de fezes de cães e gatos ao longo de uma transeção linear. Foram amostrados 0,276 km², ou 3,2% da área de 860ha do Campus. As características físicas de cada indivíduo (espécie, raça, pelagem, sexo, tamanho e marcas naturais) foram registradas para o cálculo da abundância das duas espécies na área amostrada, assim como o número de encontros por dia e por ambientes (rural e suburbano). A dieta foi analisada através das amostras de fezes que foram esterilizadas, lavadas, secas e triadas, sendo seus componentes identificados com o auxílio de referências bibliográficas. A importância de cada item foi expressa como porcentagem do número total de itens encontrados e como porcentagem de uma estimativa da biomassa consumida. A amplitude e sobreposição de nicho foram calculadas através dos índices de Levins e Pianka, respectivamente. O resultado da estimativa de abundância dos cães e gatos domésticos na área amostrada foi de 42 cães e 81 gatos. Cães e gatos são mais abundantes em ambiente suburbano que rural (T = 3,78, p < 0,001, N = 55; T = 8,38, p < 0,001, N = 55 respectivamente) e os gatos são mais abundantes que cães em ambiente suburbano (T = 6,76, p < 0,001, N = 55), porém não houve diferença significativa quanto à abundância de cães e gatos em ambiente rural (T = 0,82, p = 0,46, N = 55). Os resultados das análises das dietas indicam que os cães e gatos domésticos errantes são oportunistas de hábito generalista. Em 234 amostras de fezes foram detectadas 1212 ocorrências de 57 itens (68,4% de origem animal, 15,8% de origem vegetal e 15,8% formados por itens não alimentares). Considerando os itens de origem animal da dieta das duas espécies, invertebrados foram os mais consumidos, seguidos por mamíferos (cães: 57,05% e 25,15%; gatos: 63,24% e 20,51%, respectivamente). A amplitude de nicho (B) foi de 0,4463 para cães e 0,4892 para gatos. A sobreposição de nicho (O) foi próxima de completa (0,97108). O consumo de mamíferos por cães foi estimado entre 16,76 e 25,42 kg/ind/ano e por os gatos foi entre 2,01 e 2,9 kg/ind/ano, o que pode ser a causa das baixas densidades populacionais de pequenos mamíferos silvestres na área de estudo. / The goals of this study were to quantify the population of free-ranging dogs (Canis familiaris) and cats (Felis catus) in suburban areas; to describe and compare the diet of both species, and to estimate their predation pressure on the wildlife, at Campus " Luiz of Queiroz " of the University of São Paulo, in Piracicaba, SP. During the months of July 2002 and January 2003, visual observations and scats collection of dogs and cats were accomplished along a transect line. The sampled area comprised 0.276 km², or 3.2% of the 860ha of the Campus area. Physical characteristics of each individual (species, race, fur, sex, size and natural marks) were registered for the calculation of the abundance of both species in the sampled area, as well as the number of encounters a day and the environment (rural and suburban). The diet was analyzed through scats sterilized, washed, dried and sorted. Their components were identified with the aid of bibliographical references. The importance of each item was expressed as the percentage of the total number of items found and as the percentage of an estimate of the consumed biomass. Breadth and overlap niche were calculated through the indexes of Levins and Pianka, respectively. The results of estimate abundance of free-ranging dogs and cats in the sampled area were of 42 and 81 respectively. Dogs and cats are more abundant in suburban than rural environment (T = 3.78, p <0.001, N = 55; T = 8.38, p <0.001, N = 55 respectively) and the cats are more abundant than dogs in suburban environment (T = 6.76, p <0.001, N = 55), even though there was no significant difference between the abundance of dogs and cats in rural environment (T = 0.82, p = 0.46, N = 55). The results of diet analyses indicated that free-ranging dogs and cats are opportunistic predators of generalist habit. In 234 samples of scats 1212 occurrences of 57 items (68.4% of animal origin, 15.8% of vegetable origin and 15.8% formed by no food items) were detected. Considering the items of animal origin found in the diet of both species, invertebrates were the most consumed, followed by mammals (dogs: 57.05% and 25.15%; cats: 63.24% and 20.51%, respectively). Niche breadth (B) was 0.4463 for dogs and 0.4892 for cats. Niche overlap (O) was almost complete (0.97108). The consumption of mammals was estimated between 16.76 and 25.42 kg/ind/year for dogs and between 2.01 and 2.9 kg/ind/year for cats. This is a possible reason for the low population densities of small wild mammals in the study area.

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