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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.
651

Formigas e o Código Florestal Brasileiro : comparando Áreas de Preservação Permanente (APP) e Reserva Legal (RL)

Almeida, Rony Peterson Santos 26 February 2015 (has links)
The New Brazilian Forest Code (NCFB) presents some controversial points in its text, especially those related to the reduction or replacement of legal reserves (LRs) and Permanent Protection Areas (PPAs) for non-native vegetation or the compensation of these areas by another, on the same property. The NCFB therefore considers these two areas structurally similar and able to house and preserve the fauna and regional flora. This work aims to analyze the existence of similarity between LRs and PPAs, with focus on environmental complexity on the fragments and the use of ants as bioindicators. For this purpose, samplings were taken in six areas, three of them considered LR and three as PPA. In each area, one transect was subdivided into 30 plots of 5 x 5m and 6 m spaced. In each plot, we measured plant litter depth, density of trees and the canopy cover (%). Furthermore, in the central area of each plot, we toke a 1m² samples of plant litter to analyze the ant fauna. The relationship between ant richness and environmental variables were tested using generalized linear models (GLMS), and the species composition between areas was checked through non-metric multidimensional scaling analysis (NMDS). As a result, 116 ants morphospecies were collected, distributed in nine subfamilies and 42 genera. No difference was found in species richness of ants between LRs and PPAs and only percentage of canopy cover was significantly different. We also did not find differences of ant assemblages or functional groups between LR and PPA and this fact reinforces that the NCFB is coherent indicating that LR and PPA are similar in maintaining of local biodiversity. Thus, using the PPA in the calculation of LR (or vice versa) does not imply the reduction of local diversity of ants and consequently loss of ecological functions and interactions mediated by species of this group as these areas have similarity in structure and species diversity. / O Novo Código Florestal Brasileiro (NCFB) atualmente em vigor apresenta alguns pontos polêmicos em seu texto, em especial aqueles relacionados à redução ou substituição de Reservas Legais (RLs) e Áreas de Proteção Permanentes (APPs) por vegetação não nativa ou a compensação de uma dessas áreas pela outra, numa mesma propriedade. O NCFB portanto, considera essas duas áreas estruturalmente similares e passíveis de abrigar e conservar a fauna e flora regional. O presente trabalho visa analisar se RLs e APPs são, de fato, similares do ponto de vista ecológico, tendo como itens de analise a complexidade ambiental existente nos fragmentos e o uso de formigas como bioindicadores. Para tanto, foram realizadas coletas em seis áreas, sendo três consideradas como RL e três como APP. Em cada área foi feito um transecto e esse subdividido em 30 parcelas de 5 x 5 m, espaçadas 6 m. Em cada uma das parcelas foi medida a profundidade da serapilheira, contabilizada a densidade de árvores e medida a cobertura do dossel. Além disso, na área central de cada parcela foi retirada uma amostra de 1m² de serapilheira para analise da mirmecofauna (riqueza, composição e grupos funcionais). A riqueza de formigas, bem como de grupos funcionais foram testadas em resposta às variáveis ambientais por meio de modelos lineares generalizados (GLMs) e a composição entre as áreas verificada através da análise de similaridade (ANOSIM) e escalonamento multidimensional não-métrico (NMDS). Foram coletadas 116 morfoespécies de formigas, distribuídas em nove subfamílias e 42 gêneros. Não foi encontrada diferença na riqueza de espécies de formigas entre RLs e APPs e, dentre as variáveis ambientais analisadas, apenas houve relação positiva entre a riqueza e a porcentagem do dossel. Além disso, não houve diferença na composição de formigas nem na riqueza de grupos funcionais e estes resultados reforçam o texto atual do NCFB de que RLs ou APPs atuam de forma similar na manutenção da biodiversidade local. Desta forma, utilizar a APP no cômputo da RL (ou vice-versa) não implica na redução da diversidade local de formigas e consequentemente, prejuízo de suas funções ecológicas e de interações mediadas por espécies desse grupo já que essas áreas apresentam similaridade na sua estrutura e na diversidade de espécies.
652

Ecologia e conservação do tubarão galha-branca oceânico (carcharhinus longimanus, poey 1861)

TOLOTTI, Mariana Travassos 19 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-09-01T13:19:15Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) MTTolotti_EcologyConservationOceanicWhitetipShark_VF_FichaCatalografica.compressed aprovada.pdf: 5871232 bytes, checksum: 4af848c7c53529f3e28ffa5d085443f1 (MD5) / Made available in DSpace on 2016-09-01T13:19:16Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) MTTolotti_EcologyConservationOceanicWhitetipShark_VF_FichaCatalografica.compressed aprovada.pdf: 5871232 bytes, checksum: 4af848c7c53529f3e28ffa5d085443f1 (MD5) Previous issue date: 2016-02-19 / CAPEs / O objetivo principal da presente tese consistiu em agregar informações ao conhecimento sobre o tubarão galha-branca oceânico (Carcharhinus longimanus), principalmente no que se refere à sua distribuição, índices de abundância e preferências de habitat. Apesar de ser uma espécie muito capturada na pesca oceânica de atuns afins, informações acerca destes aspectos ecológicos são escassas e até mesmo ausentes na literatura relacionada à espécie. A tese é apresentada como um conjunto de capítulos autônomos, representando artigos científicos individuais. No primeiro capítulo-artigo foram discutidos os possíveis efeitos de medidas de manejo restritivas, implementadas recentemente por Organizações Regionais da Pesca Atuneira e que incluem algumas espécies de tubarões oceânicos. Medidas restritivas isoladas terão pouco impacto na redução da mortalidade de tubarões oceânicos. Um conjunto de medidas mitigadoras integradas será mais eficaz na conservação e recuperação das populações dessas espécies. No segundo capítulo-artigo foram analisados dados de captura e esforço de 14.835 lançamentos de espinhel pelágico realizados por embarcações arrendadas da frota atuneira brasileira, nos anos de 2004 a 2010. A CPUE nominal exibiu uma tendência de aumento gradual ao longo dos anos, variando de 0,04 em 2004 para 0,15 em 2010. A CPUE foi padronizada através de uma abordagem delta-GLM, entretanto, o índice de abundância padronizado não diferiu significativamente da CPUE nominal. Os modelos indicaram que as capturas de tubarões galha-branca são maiores para a estratégia de pesca espanhola, que se caracteriza pela utilização de anzóis em profundidades mais rasas. No terceiro capítulo-artigo, a interação entre tubarões galha-branca e a pesca de rede de cerco nos Oceanos Atlântico e Índico foi analisada, com o objetivo de investigar o potencial da utilização do banco de dados dessa pescaria para derivar índices de abundância e determinar tendências populacionais para a espécie. Dados de observadores de bordo da frota francesa combinados com dados históricos da União Soviética foram utilizados na análise. A série temporal combinada incluiu os anos entre 1986 e 2014. No Oceano Atlântico não foi possível determinar uma tendência populacional, uma vez que o índice de ocorrência foi muito baixo e não variou significativamente com o tempo. No Oceano Índico foi observada uma mudança bem-marcada no índice de ocorrência, oscilando em torno de 20% entre meados dos anos 80 e 90 e caindo para menos de 10% a partir de 2005. No quarto capítulo-artigo, a vulnerabilidade do tubarão galha-branca à pesca de espinhel pelágico foi avaliada utilizando dados dependentes e independentes da pesca. Os dados dependentes incluíram informações de diários de bordo (1999- 2011) e observadores embarcados (2004 a 2010), num total de 65.277 lançamentos de espinhel. Os dados independentes foram obtidos a partir de 8 tubarões marcados com marcas do tipo “pop-up satellite archival tag” na área onde a frota de espinhel operou. Locais de marcação e desprendimento das marcas foram relativamente próximos uns dos outros. Entretanto, os indivíduos marcados tenderam a viajar longas distâncias antes de retornar para a área de marcação. Foi observado um certo grau de filopatria à área. “Hotspots” de alta utilização dos tubarões marcados correspondeu à área sob forte pressão pesqueira. Todos os tubarões exibiram uma forte preferência por águas quentes e rasas da camada de mistura, gastando, em média, mais de 70% do tempo acima da termoclina e 95% acima de 120 m. Esse resultado justifica a maior capturabilidade da espécie em espinheis mais rasos. No quinto e último capítuloartigo, os movimentos verticais dos tubarões marcados foram analisados em detalhe. Apesar da distribuição vertical restrita, os dados indicaram que o tubarão galha-branca apresenta padrões de movimento complexos, incluindo padrões de migrações circadianas distintos e mergulhos profundos. O padrão circadiano mais frequentemente observado é caracterizado de um deslocamento à superfície durante o nascer do sol e uma tendência a permanecer em profundidades mais baixas durante o dia. Os movimentos verticais também foram influenciados pela temperatura da superfície do mar, o que pode indicar a ocorrência de termoregulação para espécie. A integração dos resultados de cada capítuloartigo proporcionou boas perspectivas para o desenvolvimento de medidas de mitigação. A evidência em relação à preferência do tubarão galha-branca por águas quentes e rasas é sólida, indicando que a remoção dos anzóis rasos do espinhel pode ser proposta para reduzir a captura incidental da espécie. O fato de variações na CPUE já terem sido observadas, sugere que esta pode ser uma medida eficaz. O comportamento filopátrico observado para o OCS também indica que a espécie pode se beneficiar com a criação de áreas marinhas protegidas. / The ultimate goal of this thesis was to generate knowledge regarding the ecology of the oceanic whitetip shark (Carcharhinus longimanus) and contribute for an ecosystem-based fishery management. The work focuses on the interactions between tuna fisheries and the species and its habitat preferences. Despite being frequently caught on high-sea fisheries, there are wide knowledge gaps regarding the ecology of the oceanic whitetip shark. The thesis is presented as a set of selfcontained standalone chapters, constructed as individual research articles. The first article-chapter provides a discussion concerning pelagic sharks and the recent species-specific banning measures implemented by Regional Fishery Management Organizations (RFMOs) in charge of tuna fisheries. It is unlikely that banning measures alone can reduce the high level of fishing mortality and recover pelagic shark’s depleted populations. Managers should be fully aware that the development and implementation of mitigation measures are critical for a more effective conservation strategy. In the second article-chapter, catch and effort data from 14,835 longline sets conducted by foreign tuna longline vessels chartered by Brazil, from 2004 to 2010, were analyzed. The nominal catch per unit of effort (CPUE) exhibited a gradual increase, varying from 0.04 sharks/1000 hooks in 2004 to 0.15 in 2010. A CPUE standardization was performed using a delta-GLM approach, but the standardized index of abundance did not differ significantly from the nominal CPUE. The models indicated that the catches of oceanic whitetip sharks are higher for the Spanish fishing strategy, which is characterized by the deployment of hooks at shallower depths. In the third article-chapter, the interaction between oceanic whitetip sharks and the purse seine fishery in the eastern Atlantic and western Indian oceans was analyzed, in order to investigate the potential of using this fishery’s database to derive abundance indexes and determine population trends for the species. Observer data from the French purse seine fleet combined with a historic database from the Soviet Union were used in the analyses. The combined time series spanned from 1986 to 2014. The occurrence index was very low for Atlantic Ocean and no marked temporal trend was observed. For the Indian Ocean a well-marked change on the occurrence index was observed, fluctuating around 20% from mid 80’s to mid 90’s and dropping to less than 10% as from 2005. In the fourth article-chapter, a combination of fisheries dependent and independent data was used to assess the vulnerability of the oceanic whitetip shark to pelagic longline fisheries. Fisheries dependent data included information from logbooks (from 1999 to 2011) and onboard observers (2004 to 2010), totaling 65,277 pelagic longline sets. Fisheries independent data were obtained from 8 oceanic whitetip sharks tagged with popup satellite archival tags in the area where longline fleet operated. Tagging and pop-up sites were relatively close to each other, although individuals tended to travel long distances before returning to the tagging area. Some degree of philopatry was observed. High utilization hotspots of tagged sharks fell inside the area under strongest fishing pressure. All sharks exhibited a strong preference for the warm and shallow waters of the mixed layer, spending on average more than 70% of the time above the thermocline and 95% above 120 m. This result explains the higher catchability of the species on shallow longline gear. In the fifth and last article-chapter, the vertical movements of tagged oceanic whitetip sharks were analyzed in detail. Despite its restricted vertical distribution, the analyses reveled that oceanic whitetips perform complex movement patterns, including distinct diel patterns and deep diving behavior. A correlation between vertical movements and sea surface temperature was also observed, suggesting the occurrence of thermoregulation for the species. The combined results of each article-chapter have provided good insights towards the development of mitigation measures. The evidence regarding oceanic whitetip shark’s preference for warm and shallow waters is solid and this information suggests that the removal of the shallow hooks from the longline gear could be proposed as a technique to reduce OCS bycatch. The fact that CPUE variations were already observed suggests that this might be an effective measure. The philopatric behavior observed for the OCS also indicates that the species could benefit from time-area closure measures.
653

Sustentabilidade das comunidades de aves em duas áreas protegidas do estado de Sergipe / Sustainability of the bird communities in two protected areas in the brazilian state of Sergipe

Aguilar, Juan Manuel Ruiz-Esparza 26 February 2014 (has links)
The destruction and modification of forested habitats in the Neotropics are a principal source of preoccupation for conservationists. Due to the fidelity to biomes or specific habitats, populations of wild birds can be used as indicators of impacts on habitat quality. Brazil is home to almost a fifth of the world s known bird species (1901 species), and also a large number of endangered species, which confers this nation with a considerable responsibility in terms of the conservation of the planet s natural resources. The present study characterizes and compares the composition and structure of the bird communities of two state conservation units (CUs) in Sergipe, as well as the knowledge of local residents with regard to this fauna, and their relationships and ecological functions, as a means of selecting indices of sustainability for the effective conservation of these populations over the long term. Data were collected in the 900-hectare Mata do Junco State Wildlife Refuge (RVSMJ), remnant of the Atlantic Forest, and the 2138 ha Grota do Angico State Natural Monument, representing the Caatinga. Data were collected in each CU using mist nets (2.5 m x 10 m), and MacKinnon lists of 10 species. A total of 129 species were recorded in each CU. In the RVSMJ, 37 species were classified as indicators of disturbed habitats (secondary forest, pastures or plantations), whereas only eight species were classified as indicators or typical of the Atlantic Forest, nine were endemic to Brazil, and two are under some risk of extinction, according to the IUCN - Herpsilochmus pectoralis (VU) and Pyriglena atra (EN). In the MNGA, 31 species were indicators of some degree of habitat disturbance, and five were specialists in decidual tropical dry forest. A single species (Herpsilochmus pectoralis) is classified as vulnerable to extinction by the IUCN, and 17 are endemic to Brazil. Local residents living in the buffer zones of the two CUs were interviewed, with the objective of documenting traditional knowledge and the use of the local fauna, with the emphasis on wild birds. Birds and mammals were cited as the principal animal found in both CUs, and in particular at RVSMJ, just over half the interviewees mentioned the titi monkey, Callicebus coimbrai. The collection of firewood, hunting, and the capture of animals for domestication were the responses that most exemplified the use of the local natural resources. The number of bird species known by local residents varied from zero to 13, and most interviewees cited fruit, seeds, and insects as food sources. The maintenance of local bird populations was seen as an important factor for the conservation of local habitats, and the control of deforestation as the principal means of protecting natural resources. These results were used to elaborate indices of sustainability based on the Pressure/State/Impact/Response approach, relating the applicability of the model to the anthropogenic impacts on the bird communities. This study intends to consolidate the management of the CUs and guarantee their conservation over the long term, providing a functional model that can be replicated in other conservation units. / As alteracoes ou destruicao dos habitats nas florestas das regioes neotropicais sao um fator de interesse para a conservacao. As aves silvestres sao usadas como indicadores das alteracoes ou mudancas na qualidade dos habitats, pelo grau de fidelidade a biomas e habitats especificos. No Brasil encontramos quase uma quinta parte das aves conhecidas do mundo (1.901 especies), em contrapartida tambem possui um elevado numero de especies ameacadas, tal situacao deposita uma grande responsabilidade ambiental para o pais, alem do enorme desafio no ambito da conservacao dos recursos naturais. O presente trabalho tem como objetivos caracterizar e comparar a estrutura das comunidades de aves de duas Unidades de Conservacao (UC) estaduais de Sergipe, verificar o conhecimento das populacoes locais em relacao as especies de aves, assim como sua funcao ecologica finalmente selecionar indicadores de sustentabilidade, visando garantir sua conservacao efetiva em longo prazo. Os levantamentos das aves foram realizados no Refugio de Vida Silvestre da Mata do Junco (RVSMJ), (.900 ha, de Mata Atlantica) e no Monumento Natural da Grota do Angico (MNGA), (2.138 ha, de Caatinga). Dentro destas UCs foram realizadas amostragem sistematicas de aves utilizando dez redes de neblina (2,5 x 10 m) e listas de MacKinnon (10 especies). Em ambas as areas foram encontradas 129 especies de aves, no RVSMJ, 37 especies sao classificadas como indicadoras de habitat com disturbio (floresta secundaria, areas de agricultura ou pastos), enquanto unicamente oito especies sao classificadas como indicadoras ou tipicas da Mata Atlantica, nove sao endemicas do Brasil, e duas estao classificadas em alguma categoria de risco pela IUCN, Herpsilochmus pectoralis (VU) e Pyriglena atra (EN). Ja no MNGA, 31 especies sao indicadoras de habitat com algum tipo de disturbio, somente cinco especies sao especialistas de floresta tropical decidua. Unicamente uma especie classificada como vulneravel na IUCN (Herpsilochmus pectoralis) e 17 especies sao endemicas do Brasil. Foram realizadas entrevistas com os moradores das zonas de amortecimento das UCs estudadas, com o intuito de verificar o conhecimento tradicional e uso da fauna com enfase nas aves silvestres. Em ambas as areas foram citadas as aves e os mamiferos, como os principais animais que moram na mata, sendo que no RVSMJ pouco mais da metade dos entrevistados citaram o Guigo. O uso da lenha e captura de animais para criacao em cativeiro e para caca, foram as respostas que evidenciam os usos da mata. Sobre o numero de aves conhecidas as respostas varia de zero a 13 especies, a maioria citaram as frutas, sementes e insetos como os alimentos das aves. Caso as aves sumissem da mata, a maioria relacionou este fato com o fim da mata, indicando evitar o desmatamento como a principal acao para proteger as matas. A partir destes resultados, foram elaborados indicadores de sustentabilidade baseados na metodologia Pressao/Estado/Impacto/Resposta, relacionando sua aplicabilidade aos efeitos dos impactos antropicos produzidos nas comunidades de aves. Este estudo pretende consolidar o manejo das UCs, visando garantir seus objetivos de conservacao em longo prazo, gerando um modelo que pode ser replicado em outras unidades de conservacao.
654

Influência das características fisiográficas sobre a estrutura e composição da comunidade de macroinvertebrados bentônicos em duas ecorregiões neotropicais / Physiographic characteristics influence on the structure and composition of the benthic macroinvertebrate community in two neotropical ecoregions

Ferronato, Michelli Caroline 28 September 2012 (has links)
Made available in DSpace on 2017-07-10T18:13:15Z (GMT). No. of bitstreams: 1 Michelli Carolina Ferronato.pdf: 725223 bytes, checksum: b229eec1bf9717c15bc56d484e0aa987 (MD5) Previous issue date: 2012-09-28 / Ecoregion is an area that has the same physiographic characteristics (climate, geology, soil altitude, characteristics and land cover, vegetation) in a given region. This study aims to investigate the differences of the macroinvertebrate community in two ecoregions different of Paraná. Specifically we aim to answer: i) the physiographic characteristics of each ecoregion influence the structure and attributes of the benthic macroinvertebrate community? ii) What physiographic characteristics influence on the community? iii) The classification of functional groups is similar among ecoregions? iv) It is possible to identify groups indicators for each ecoregion? Macroinvertebrates were collected in two ecoregions of Paraná, 6 rivers in each ecoregion located in two protected areas (State Park Guartelá (PEG) and Iguaçu National Park (PNI)). To collect biological, used a collector type Hand-net, in addition, physical and chemical samples of the water were measured (pH, dissolved oxygen, altitude, water temperature, alkalinity, hardness, total nitrogen and total phosphorus) and analysis of the substrate. As a result, the ANOVA showed no significant differences between the ecoregions as attributes, however, the structure was different according to the PCA. Functional groups had the same composition, but with different percentages for each ecoregion. The indicator taxa of PEG were Baetidae, Aeshnidae, Coenagrionidae, Chironomidae and Ceratopogonidae and for the PNI, the indicator taxa were Leptohyphidae, Caenidae, Perlidae, Pleidae and Psephenidae. Thus, we conclude that the ecoregions were different as macroinvertebrate community structure due to the influence of the physical environment. / Ecorregião é uma área que possui as mesmas características fisiográficas (clima, geologia, solos, altitude e características de cobertura do solo, vegetação) em uma determinada região. Este estudo tem por objetivo verificar as diferenças da comunidade de macroinvertebrados em duas ecorregiões do Paraná. Especificamente objetiva-se responder: i) As características fisiográficas de cada ecorregião influenciam na estrutura e atributos da comunidade de macroinvertebrados bentônicos? ii) Quais características fisiográficas exercem influência sobre a comunidade? iii) A classificação dos grupos funcionais é semelhante entre as ecorregiões? iv) É possível identificar grupos indicadores para cada ecorregião? Foram coletados macroinvertebrados em duas ecorregiões do Paraná, sendo 6 rios em cada ecorregião localizados em duas Unidades de Conservação (Parque Estadual do Guartelá (PEG) e Parque Nacional do Iguaçu (PNI)). Para a coleta biológica, utilizou-se um coletor do tipo Hand-net, além disso, amostras físicas e químicas da água foram mensuradas (pH, oxigênio dissolvido, altitude, temperatura da água, alcalinidade, dureza, nitrogênio total e fósforo total) e análise do substrato. Como resultados, a ANOVA não mostrou diferenças significativas entre as ecorregiões quanto aos atributos, porém, a estrutura foi diferente segundo a PCA. Os grupos funcionais tiveram a mesma composição, porém com porcentagens diferenciadas para cada ecorregião. Os táxons indicadores do PEG foram Baetidae, Aeshnidae, Coenagrionidae, Chironomidae e Ceratopogonidae e para o PNI, os táxons indicadores foram Leptohyphidae, Caenidae, Perlidae, Pleidae e Psephenidae. Desta forma, concluímos que as ecorregiões foram diferentes quanto a estrutura da comunidade de macroinvertebrados devido a influencia das condições físicas do ambiente.
655

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.
656

Biodiversité et caractéristiques physico-chimiques des sols de jardins associatifs urbains français / Biodiversity and geochemical characteristics of French urban vegetable garden soils

Joimel, Sophie 09 March 2015 (has links)
Les jardins associatifs (p.ex. familiaux) connaissent aujourd’hui un regain d’intérêt en France et sont souvent associés à de nombreuses fonctionnalités et services au sein des systèmes urbains (p.ex. alimentation, support de biodiversité). A ce titre, les sols de jardins représentent un enjeu majeur et leur caractérisation, aussi bien physicochimique que biologique nécessite d’être mieux appréhendée. Quelle est la relation entre les caractéristiques physicochimiques et les pratiques de jardinage ? Quelle est l’influence de ces propriétés sur la biodiversité fonctionnelle et taxonomique ? Pour répondre à ces questions, des investigations ont été menées au sein de jardins potagers choisis pour être représentatifs de la variabilité de ces systèmes sur le territoire national français. Les travaux ont porté sur les propriétés agronomiques et toxiques des terres de surface. La végétation et les microarthropodes du sol ont aussi été caractérisés. A l’aide de plusieurs bases de données, des comparaisons avec d’autres usages de sols ont permis de replacer les sols de jardins étudiés au sein de la couverture pédologique française. Ainsi, en dépit de teneurs totales élevées en métaux, les sols de jardins présentent une fertilité physicochimique indéniable et sont le support d’une biodiversité du sol élevée. En revanche, pour la végétation, une homogénéisation biotique croissante au sein des villes est observable avec la sélection d'espèces ayant des traits adaptés au milieu urbain. Les sols de jardins, pourtant situés dans un contexte urbain fortement anthropisé, ne doivent donc pas être considérés comme des écosystèmes dégradés, mais au contraire comme une ressource à préserver / Community gardens (e.g. allotments, shared gardens) currently experience a renewed interest among the French and are often associated with many functions and services within urban ecosystems (vegetable supply, biodiversity). As such, garden soils are a major concern and their characteristics (physico-chemical as well as biological ones) need to be better understood. What connection is there between the functional quality of garden soils and the alteration of their physico-chemical characteristics by gardening practices? What influence do these properties in garden soils have on functional and taxonomic biodiversity? In order to answer these questions, investigations were conducted in vegetable gardens chosen as representative of the ecosystemic variability within French territory. On one hand work was done on the topsoil's agronomical properties and toxicity. On the other hand these soils were characterised using several biological indicators, such as vegetal species and soil microarthropods. With the help of several databases, we were able to place these garden soils among other french topsoils by comparing them to other land uses. Despite having high total metallic contents garden soils show an undeniable physico-chemical fertility, and support a high level of soil biodiversity. In contrast, an increasing plant biotic homogenisation can be observed within cities. Indeed, there is a selection of species with traits that are particularly adapted to urban environments. In conclusion, even though garden soils exist in a highly anthropised urban context they are not degraded ecosystems, but rather a precious resource
657

Zu den Auswirkungen experimenteller Waldneugründungs- und Waldumbaumaßnahmen auf die saprophage Invertebratenfauna an extrem immissionsgeschädigten Kammlagenstandorten des Osterzgebirges (Sachsen): Oligochaeta: Enchytraeidae, Lumbricidae; Acari: Oribatida; Insecta: Collembola: Bodenzoologisch-ökologische Untersuchungen

La France, Martin 29 November 2002 (has links)
The effects of reafforestation with seedlings of spruce, birch, mountain-ash, beech and larch, partially in combination with liming and removal of the topsoil layer before planting, on the community of saprophagous invertebrates (lumbricids, enchytraeids, oribatids, collembolans) were examined. The study area was located on plateau sites of the eastern Ore Mountains (Saxonia, Germany). Investigations were carried out on study sites exposed to high sulphur dioxide immissions and reforested 3 respectively 10 years ago. Invertebrates were sampled by the extraction of soil cores and by the ?electro-octett-method? (lumbricids). Additionally, the ?minicontainer method? was used to investigate decomposition rates of different types of litter. On the control area, a diedback spruce stand, the decomposer community showed high adaptations to the acidic soil substrate and was dominated by few enchytraeid species. Long-termed loss of tree shelter, liming and topsoil removal before planting resulted in a severe decline of most saprophagous species. However, changes in invertebrate community pattern due to different plantations were not found. A comparison of leaf and needle litter decomposition rates resulted in the following order: birch (k = 0.50) &amp;gt; mountain-ash (0.40) &amp;gt; spruce (0.30) &amp;gt;&amp;gt; larch (0.12). Considering all investigated taxa, the metabolic decomposing capacity of the larch litter reached 39 %, that the spruce litter 54 % of the foliage litter results. / Anläßlich des kompletten Ausfalls der Fichte in den extrem immissionsbelasteten Kammlagen des Osterzgebirges (Sachsen) wurden im Rahmen eines interdisziplinären Verbundprojektes verschiedene Waldbaukonzepte hinsichtlich ihrer Einflüsse auf die saprophage Invertebratenfauna (Enchytraeidae, Lumbricidae, Oribatida, Collembola) untersucht. Zur Disposition standen Verfahren zur Waldneugründung (Kulturparzellen mit Reihenpflanzung von Birke, Eberesche oder Fichte; zusätzlich waldbaulich unbeeinflußte Sukzessionsparzellen) und zum Waldumbau (Kulturparzellen mit Reihenpflanzung von Buche oder Lärche nach Abtrieb und flächigem Oberbodenabschub). Ein absterbender Fichtenreinbestand in fortgeschrittener Auflösung diente als Referenz- bzw. Korrelationsmaßstab. Die Erfassung der Mesofauna erfolgte über die Extraktion von Stechrohrproben. Lumbriciden wurden mit der Elektrooktett-Methode aufgenommen. Neben der flächenbezogenen Datenerfassung wurden 1.200 mit Blattstreu von Birke, Eberesche, Fichte und Lärche befüllte Minicontainer über 19 Monate auf einer Sukzessionsparzelle exponiert, um substratspezifische Abbaugeschwindigkeiten zu ermitteln und faunistische Sukzessionsverläufe zu studieren. Die Referenzfläche zeichnete sich durch eine stark enchytraeendominierte Zersetzergemeinschaft aus, die deutliche Anzeichen einer kalkungsbedingten Überprägung erkennen ließ. Der Enchytraeenanteil an den potentiellen Umsatzleistungen der untersuchten Destruententaxa (berechnet über metabolische Äquivalenzwerte) lag bei über 90 %. Hiervon ausgehend zeigten die Zersetzergemeinschaften der Versuchsanlagen &amp;quot;Waldneugründung&amp;quot; und &amp;quot;Waldumbau&amp;quot; stark divergierende Entwicklungsrichtungen. Als ausschlaggebende Faktoren konnten Schirmverlust, Kalkung und Oberbodenbeseitigung wahrscheinlich gemacht werden. Dagegen waren Einflüsse der unterschiedlichen Kulturbaumarten kaum nachzuweisen. Die streuspezifischen Dekompositionsgeschwindigkeiten unterschieden sich wie folgt: Birke (k = 0,50) &amp;gt; Eberesche (0,40) &amp;gt; Fichte (0,30) &amp;gt;&amp;gt; Lärche (0,12). Diese vergleichsweise geringen Abbauraten stehen überwiegend mit dem rauhen Montanklima in Zusammenhang. Enchytraeen besiedelten alle Streutypen zügig, während Collembolen vor allem die Ebereschenstreu verzögert aufsuchten und mit geringster Dichte bevölkerten. Oribatiden zeigten die geringste Besiedlungsgeschwindigkeit und hatten wie die Enchytaeen in der Laubstreu signifikant höhere Wohndichten. Nur Steganacarus spinosus zeigte eine besondere Affinität für Nadelstreu. Das metabolische Leistungspotential des Destruentenbesatzes der Lärchenstreu erreichte 39 %, das der Fichtenstreu 54 % der Laubstreuresultate.
658

Ökologie der Fischbestände in Fließgewässern des Khentii-Gebirges (Mongolei): Bestandsaufbau, Dynamik und Gefährdung durch den Gold-Tagebau

Krätz, Daniel A. 25 March 2009 (has links)
Die Fischfauna der Mongolei umfasst 64 Arten, von denen aktuell in der Roten Liste elf Arten als regional bedroht und vier Arten als potentiell bedroht eingestuft werden. Eine der wichtigsten Ursachen für den Rückgang der Arten ist der Gold-Tagebau. Viele Goldvorkommen lagern in alluvialen Sedimenten der Fließgewässerauen und werden durch großflächigen Abbau und mechanische Auswaschungsprozesse gewonnen. Dies führt zu erheblichen Störungen im Schwebstoff- und Stoffhaushalt der Fließgewässer und beeinflusst die Habitatverfügbarkeit und -qualität für die Fischfauna. Das primäre Ziel der Arbeit war daher die abiotische und ichthyologische Charakterisierung ausgewählter Referenzgewässer sowie durch Gold-Tagebau beeinflusster Gewässer und die Quantifizierung der Einflüsse des Gold-Tagebaus. Ein weiteres Ziel lag in der Formulierung von angepassten Managementstrategien für eine nachhaltige Entwicklung des expandierenden Bergbausektors in der Mongolei. Die Untersuchungen fanden in den Jahren 2003 bis 2006 an vier rhitralen Gewässern des Khentii-Gebirges im Nord-Osten der Mongolei statt. Die Erfassung der Fischbestände erfolgte mit Hilfe von Elektrofischfanganlagen und Reusen, wobei die vorkommenden Habitate repräsentativ erfasst wurden. Zusätzlich erfolgten Untersuchungen zum Stoffhaushalt der Gewässer und der Gewässersohle. Die relevanten Habitate wurden kartiert und Experimente zum Wanderverhalten ausgewählter Arten durchgeführt. Die Untersuchungen erbrachten folgende wesentliche Ergebnisse: 1. Die Fischfauna der untersuchten Gewässer umfasste 14 Taxa mit überwiegend rhitralen Charakterarten wie Salmoniden, Äschen und Elritzen. Die Fischbestände wiesen eine sehr hohe saisonale Dynamik auf, wobei kleinere Fließgewässer im Herbst verlassen und im Frühjahr neu besiedelt wurden. 2. Der Gold-Tagebau führte zu erhöhten Schwebstoffkonzentrationen und zur Kolmation des hyporheischen Interstitials. Die physikalisch-chemischen Untersuchungen ergaben vor allem eine signifikante Erhöhung der Wassertemperaturen in den belasteten Gewässerabschnitten. Durch den Gold-Tagebau wurden weiterhin die Auenvegetation und die natürlichen Uferstrukturen zerstört, was zu vielfältigen Habitatveränderungen führt. 3. Die untersuchten Effekte des Gold-Tagebaus sind als sublethal und verhaltens-verändernd einzustufen. Sie wirken sich z.B. auf das funktionale Gefüge der verschiedenen trophischen Ebenen des Fließgewässerökosystems aus. So wiesen zahlreiche Fischarten einen signifikant verringerten Konditionsfaktor auf, der offensichtlich bottom-up gesteuert durch verminderten Aufwuchs und geringere Abundanzen des Makrozoobenthos verursacht wird. Auch wurde ein deutlicher Einfluss auf die Fischwanderung festgestellt, der vermutlich durch ungünstige physikalisch-chemische oder hydraulische Habitateigenschaften innerhalb des Abbaugebiets verursacht wird. Für Arktische Äschen und Lenok ist das Abbaugebiet nicht oder nur eingeschränkt passierbar. 4. Die Kolmation des Kieslückensystems führte zum Verlust von Laich- und Überwinterungshabitaten und ist daher als ein gravierender Einflussfaktor für die lokale Fischfauna einzustufen. 5. Letale Effekte wie Kiemen- oder Schleimhautverletzungen auf Grund von direkter Schädigung der Tiere durch die erhöhten Schwebstofffrachten wurden nicht beobachtet. Im Rahmen der Arbeit wurden ökologische Grundlagenkenntnisse zu Fischbeständen und Populationsdynamiken im Nord-Osten der Mongolei erarbeitet. Diese Informationen tragen zu einem besseren Verständnis der Gefährdungsursachen bei. Auf Basis der gewonnenen Erkenntnisse über die Ökologie der Arten und der Einflüsse des Gold-Tagebaus wurden Managementempfehlungen unterschiedlicher Priorität formuliert und an Hand eines Fallbeispiels exemplarisch bearbeitet. Darüber hinaus wurden Grundlagen für ein ökologisches Monitoring des Gold-Tagebaus entwickelt. / The fish fauna of Mongolia comprises 64 species of which eleven are regionally endangered and four potentially endangered according to the Red List of Mongolian Fish. Gold mining is regarded as one of the major causes for declining fish populations. Many gold deposits are found in the alluvial sediments of the floodplains and are extracted by large scale mining and mechanical elutriation. This heavily disturbs the balance of suspended sediments and matter in running waters and affects the habitat availability and quality for the fish fauna. Thus, the primary objective of this study was the abiotic and ichthyological characterization of selected reference waters and waters influenced by gold mining as well as the quantification of gold mining effects. Furthermore, an aim was the formulation of management strategies for a sustainable development of the expanding mining sector in Mongolia. The investigation took place from 2003 to 2006 at four rhitral waters of the Khentii Mountains in north-east Mongolia. Data acquisition of the fish fauna was carried out with electric fishing devices and fish traps on representative habitats. In addition, the balance of mater and characteristics of the hyporheic zone were analyzed, relevant habitats mapped and the migratory behavior of selected species experimentally studied. The following major results were obtained from this research: 1. The fish fauna of the examined waters comprised 14 taxa dominated by rhitral characteristic species like salmonids, arctic grayling and minnows. The fish population was strongly seasonally influenced, whereas small running waters being repopulated yearly in spring. 2. Gold mining brings about an increase in concentrations of suspended sediment and clogging of the hyporheic interstitial. Physical-chemical investigations primarily identified a significant rise in water temperatures in the polluted water sectors. Furthermore, gold mining degrades floodplain vegetation and natural bank structures causing varied habitat changes. 3. The examined gold mining effects are sublethal to fish or influence their behavior. They disrupt the functional arrangement of the different trophic levels of the river ecosystem. Thus, the condition of some fish species was significantly decreased, evidently regulated bottom-up by depleted periphyton and reduced abundances of macro invertebrates. Moreover, a strong influence on the river continuum was assessed. Arctic grayling and lenok did not migrate through the mining area, possibly due to unfavorable physical-chemical or hydraulic conditions within the mining site. 4. The clogging of the river bed substrate resulted in a loss of spawning and hibernation habitats and thus must be regarded as a major thread to the local fish fauna. 5. Lethal effects like injuries of gills or skin by direct lesions of suspended particles could not be observed. In this study basic ecological knowledge and population dynamics of the fish fauna in north-east Mongolia have been identified. This information is fundamental for a better understanding of the causes of endangerment. Based on the findings on the ecology of fish species and the influences of gold-mining management recommendations of different priority were developed and exemplified in a case study. Furthermore, this study worked out basic principles for an ecological monitoring of gold mining.
659

Právní a politická dimenze mezinárodního obchodu s ohroženými druhy volně žijících živočichů a rostlin / Legal and Political Dimension of International Trade in Endangered Species of Wild Fauna and Flora

Ulík, Karel January 2014 (has links)
The thesis deals with the issue of compliance in the context of international treaties on protection of endangered species. Two important treaties are subject of the analysis - the 1973 Convention on International Trade in Endangered Species of Wild Fauna and Flora (known as CITES) and the 1946 International Convention for the Regulation of Whaling. My research focuses on the question whether member states comply with their obligations arising from the treaties. If they do not, then I look for a response to the violation such as use of compliance instruments (e. g. sanctions) and its effect on the breaching state, mainly if the response (if there was any) was successful in making the state come back into compliance. Finally, based on experience with CITES, ICRW and other multilateral environmental treaties, I attempt to design some of the new ICRW compliance mechanism features in order to increase its effectiveness.
660

Invasive

James, Lindsey Taylor 08 May 2018 (has links)
No description available.

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