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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.
71

Freshwater cyanoprokaryota blooms in the Swan Coastal Plain wetlands: ecology, taxonomy and toxicology

Kemp, Annabeth S. January 2009 (has links)
Relatively little published information on cyanoprokaryote (blue-green algal) blooms in the freshwater wetlands in Western Australia is available. There has been little research on the urban lakes and rivers, examining the relationship between environmental conditions and toxin-producing blooms. In this project the ecology, morphology and toxicity of cyanoprokaryota blooms in 27 metropolitan lakes and sumplands, as well as three major rivers, from 2000 to 2003, on the Swan Coastal Plain (SCP) in the southwest of Western Australia were investigated. / A total of 24 species were identified and described, of which nine species had not been previously documented in the area. This included the potentially toxic species Cylindrospermopsis raciborskii, Aphanizomenon ovalisporum and Anabaena bergii var. limnetica. An illustrated guide to the common bloom-forming species was generated using conventional taxonomic criteria. / Microcystis flos-aquae and Microcystis aeruginosa were the dominant bloom-forming cyanoprokaryotes, widespread in their distribution. Anabaena circinalis, A. bergii var. limnetica and Anabaenopsis elenkinii were the common filamentous species. Anabaena circinalis was common to certain freshwater sites, while A. bergii var. limnetica and A. elenkinii occurred in salinity ranging from fresh (< 1ppt) to hyposaline (3-10 ppt). Sites with similar species assemblages were identified using two-way indicator species analysis and clustering analysis. From this, a distinct distribution pattern emerged, which was defined by the main genera observed in the lakes – Microcystis, Anabaena, Aphanizomenon and Anabaenopsis. / The spatial and temporal distribution of the common bloom-forming cyanoprokaryote species was examined in conjunction with spring-summer physico-chemical data using principal component analysis. It was found that pH, water temperature and electrical conductivity/salinity accounted for variations among the lakes, with electrical conductivity the variable explaining the greatest variation. Lakes located on the coast, or further inland at the base of the Darling Scarp, were more hyposaline to saline, and the remaining lakes were fresh. Although the SCP lakes form consanguineous groups based on geochemistry and hydrology, no similarities among them were found in terms of water quality. / The relationship between nitrogen (N) and phosphorus (P) concentrations (total and dissolved inorganic) and cyanoprokaryote community structure (N-fixing versus non-N-fixing species) was investigated in five selected lakes; Yangebup Lake, Bibra Lake, Blue Gum Lake, Tomato Lake and Emu Lake. The lakes ranged from mesotrophic to eutrophic and supported spring-summer blooms containing multiple species. Overall an inverse relationship between cyanoprokaryote abundance and total ambient nutrient concentrations at the time of the blooms was evident. No transition in dominance in the community was observed in Yangebup Lake, Emu Lake and Bibra Lake, as they were dominated by non-heterocytic species (M. aeruginosa and M. flos-aquae) throughout spring and summer. For Yangebup Lake and Bibra Lake, the abundance of non-heterocytic species decreased concomitantly with decreasing dissolved inorganic N. In contrast, heterocytic species (A. circinalis) dominated the spring community in Tomato Lake, and summer community in Blue Gum Lake, when N and P concentrations were at their highest. / The presence of microcystins in Microcystis dominated blooms was examined using high performance chromatography. A total of 32 natural bloom samples, representing 13 lakes, were analysed for microcystin variants; -LR, -RR and -YR. Twenty-eight samples proved to be toxic with the highest total microcystin concentration from 1645 to 8428.6 µg L[superscript]-1, the lowest concentrations were less than 10 µg L[superscript]-1 with some below the detection limit. Microcystis aeruginosa and M. flos-aquae were associated with these microcystin-containing blooms, although M. flos-aquae appear to be less toxic. The presence of Nodularia spumigena in the Lake Yangebup was associated with high concentrations of nodularin (1664 µg L[superscript]-1). / Employing enzyme-linked immunosorbent assay for microcystins and the brine shrimp (Artemia) bioassays allowed a greater number of lake samples to be analysed and provided a rapid assessment of toxicity. The three methods for cyanotoxin detection verified Yangebup Lake, Herdsman Lake, Hyde Park, Jackadder Lake and Emu Lake as highly toxic sites. Low toxicity was demonstrated in samples from Lake Goollelal, Lake Joondalup, Lake Claremont, Blue Gum Lake and North Lake. These results provided the first evidence of cyanotoxin producing blooms in urban lakes of the SCP. / A comparative study on cyanoprokaryota blooms in Swan River estuary, upper Canning River and upper Serpentine River found that these sites, although hyposaline to saline, contained species that were common in the freshwater lakes. Sampling the river systems showed M. aeruginosa, M. flos-aquae, A. circinalis, A. elenkinii and Planktothrix planctonica to be cosmopolitan in distribution, present in SCP wetlands of varied salinity. Similarities between the upper Canning River and lakes in environmental conditions and species assemblage were demonstrated using multivariate analyses. / Toxin analysis of bloom samples from the Swan River and upper Canning River revealed microcystin concentrations were less than that of the surrounding lakes (1.05-124.16 µg L[superscript]-1). Similarly, nodularin concentrations were higher in Yangebup Lake than the upper Serpentine River. However, the dominance of Anabaena in Canning River samples, and the highly toxic result from the Artemia bioassay suggests microcystin is not the predominant cyanotoxin in this wetland. / This study has produced an overview of the distribution and morphology of cyanotoxin-producing cyanoprokaryotes in the SCP wetlands. The data presented provide the basis for further cyanoprokaryote research in Western Australia, in particular the molecular characterisation of bloom-forming toxic species.
72

Relações florísticas, estruturais e ecológicas entre as florestas do topo da Serra do Mar e as florestas de restinga no Estado de São Paulo / Floristic, structural and ecological relationships between restinga florest and upper montane rain florest in Serra do Mar, SP, Brazil

Joao Carlos Miguel Tomaz Micheletti Neto 18 December 2007 (has links)
As comunidades florestais periféricas às florestas que recobrem o sopé e as médias encostas da Serra do Mar apresentam uma convergência de fisionomias e aspectos xeromórficos, sustentada por floras que estão relacionadas quanto às suas origens. Como estas semelhanças podem indicar condições ecológicas similares, o trabalho investigou qualitativa e quantitativamente se as semelhanças fisionômicas, entre a Floresta do Topo dos Morros da Serra do Mar e a Floresta Seca de Restinga no Estado de São Paulo, são acompanhadas por semelhanças florísticas e estruturais. Esta investigação teve como objetivos: caracterizar e comparar, em termos fitossociológicos, as florestas secas de restinga e as florestas do topo das escarpas atlânticas; e analisar as relações entre possíveis padrões florísticos e estruturais do componente arbóreo destas florestas e condições edáficas e climáticas de seus ambientes. A amostragem foi realizada a partir de 10 parcelas de 10 m X 10 m em cada uma das seis áreas de estudo. Para o topo da Serra do Mar considerou-se a floresta nas seguintes Unidades de Conservação: Estação Biológica de Boracéia; Núcleo Curucutu do PESM e Parque Estadual Intervales. Para a floresta seca de restinga, as áreas de estudo foram: Núcleo Picinguaba do PESM, Estação Ecológica Juréia-Itatins e Parque Estadual Ilha do Cardoso. Através da descrição fitossociológica das comunidades e de técnicas de análise multivariada para classificação e ordenação, observou-se que as áreas de floresta do topo das encostas são pouco similares florística e estruturalmente em relação às florestas secas de restinga. As pequenas semelhanças entre as florestas estudadas dizem respeito às espécies de grande plasticidade ecológica e que, por isso, possuem ampla distribuição geográfica. As diferenças florísticas e estruturais foram determinadas pelas espécies oriundas das florestas que recobrem as encostas da Serra do Mar, sendo que nehuma das espécies consideradas importantes é endêmica de um dos tipos florestais, não sustentando, assim, a convergência ecológica. / Plant communities at the periphery of the Atlantic rainforest that recover the lower and middle slopes of Serra do Mar presents a convergence of physiognomy and xeromorphycs aspects, supported by floras that are related on its origins. As these convergence can indicate similar ecological conditions, this present work investigated if the similarities between Upper Slope Forest and the Restinga Forest in the State of São Paulo, Brazil, are followed by floristic and structural similarities. This inquiry had two objectives: characterize and compare the Upper Slope Forest and the Restinga Forest in its phytosociological aspects; analyze the relationships between edaphic and climatic conditions and floristic and structural patterns of the arboreal component of these forests. To characterize the Upper Slope Forest was considered forests in the following Conservation Units: Estação Biológica de Boracéia, Núcleo Curucutu do Parque Estadual da Serra do Mar and Parque Estadual Intervales; and to characterize the Restinga Forest the study areas were in the following Conservation Units: Núcleo Picinguaba do PESM, Estação Ecológica Juréia-Itatins and Parque Estadual Ilha do Cardoso. For structural vegetation analysis, were used 10 plots of 10 x 10 m in each area. The phytosociological description and multivaried analysis of classification and ordination showed that areas of Upper Slope Forest and Restinga Forest have low similarity. The resemblances are based on occurrence of broad ecological plasticity species and, therefore, of wide distribution. On the other hand, the floristic and structural heterogeneity is consequence of the predominance, in each forests type, of different species from the Atlantic rainforest that recover the lower and middle slopes of Serra do Mar, not supporting the ecological convergence hypothesis.
73

Configuração socioambiental da planície costeira no município de Paripueira – Alagoas

Santos, Edilsa Oliveira dos 20 June 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Coastal areas are dynamic and unstable, fragile and vulnerable environments that comprise the transition zone between the continent and the sea, bringing together unique landscapes, but complex, due to their natural dynamics, associated with the socioeconomic activities that configure these spaces. It is a territorial portion of great diversity of natural resources, be it in relation to fauna or flora. These characteristics are attractive, whether for rest, recreation, leisure, sports or economic activities. In regions where constructions on the coastline have been intensified in a direct or indirect manner, the changes in the sedimentary balance and consequently the decharacterization of this environment, accelerated by social factors, become perceptible. In this sense, the importance of a study on the socioenvironmental issues and on the degree of fragility of the coastal environments is evidenced, to provide subsidies for land use planning. Space and landscape are the categories of this research analysis, whose general objective is to analyze the socioenvironmental dynamics in the Coastal Plain of the municipality of Paripueira, located on the north coast of Alagoas. For that, the characterization of the physical elements was done, to understand the operation of the environmental system of the spatial cut of the research. For the construction, three levels of research were adopted as methodological procedures: exploratory, descriptive and explanatory, divided into three stages, carried out through a bibliographical review, documentary research, fieldwork and study, with the creation of thematic maps in a Geographic Information Systems (GIS) environment. The results indicate that the Coastal Plain in question is formed by deposits dated from the Quaternary, developed from the events of marine transgressions and regressions. Consisting of marine terraces, plain fluvio lagoon, fluviomarinha, dunes, coastal strands and mangroves. Its structure indicates a marked level of environmental fragility, caused by the socioeconomic demands of this environment that have shown population growth. The urban occupation is distributed irregularly, with modification and degradation in the natural landscape, having as main motivating agent, the tourist activities. It is inferred, therefore, that it is necessary to awaken in society the need through scientific research, management and monitoring actions and try to find a balance between the use and conservation of coastal environments, through investments that aim to minimize damages to the environment, and environmental education programs with the local population in the quest to change people's attitudes and behaviors towards the environment. / As áreas litorâneas são ambientes dinâmicos e instáveis, frágeis e vulneráveis, que compreendem a zona de transição entre o continente e o mar, reunindo paisagens peculiares, porém complexas, devido a sua dinâmica natural, associados às atividades socioeconômicas que configuram esses espaços. É uma porção territorial de grande diversidade de recursos naturais, seja em relação à fauna ou à flora. Essas características são atrativas, sejam para repouso, recreação, lazer, práticas esportivas ou atividades econômicas. Em regiões onde as construções na linha de costa têm sido intensificadas de maneira direta ou indireta, tornam-se perceptíveis as alterações no balanço sedimentar e consequentemente a descaracterização desse ambiente, acelerado por fatores sociais. Neste sentido, evidenciam-se a importância de estudo sobre as questões socioambientais, e sobre o grau a fragilidade os ambientes costeiros, no intuito de fornecer subsídio para o ordenamento territorial. O Espaço e a paisagem constituem as categorias dessa análise da pesquisa, cujo objetivo geral é analisar a dinâmica socioambiental na Planície Costeira do município de Paripueira, localizado no litoral norte de Alagoas. Para tal, foi feita a caracterização dos elementos físicos, com o intuito de compreender o funcionamento do sistema ambiental do recorte espacial da pesquisa. Para a construção adotou-se como procedimentos metodológicos três níveis da pesquisa: exploratório, descritivo e explicativo, divididos em três etapas, realizados mediante revisão bibliográfica, pesquisa documental, trabalho de campo e gabinete, com a confecção dos mapas temáticos em ambiente dos Sistemas de Informações Geográficas (SIG). Os resultados apontam que a Planície Costeira em questão é formada por depósitos datados do Quaternário, desenvolvida a partir dos eventos de transgressões e regressões marinhas. Constituída por terraços marinhos, planície fluviolagunar, fluviomarinha, dunas, cordões litorâneos e mangues. Sua estrutura aponta nível de fragilidade ambiental acentuado, provocado pelas demandas socioeconômicas conferidos a esse ambiente que têm apresentado crescimento populacional. A ocupação urbana apresenta-se distribuída de forma irregular, com modificação e degradação na paisagem natural, tendo como principal agente motivador, as atividades turísticas. Infere-se, portanto, que é preciso despertar na sociedade a necessidade através de pesquisas cientificas, ações de gerenciamento e monitoramento e tentar encontrar uma situação de equilíbrio entre o uso e conservação dos ambientes costeiros, através de investimentos que visem minimizar os danos ao meio ambiente, e programas de educação ambiental junto à população local na busca de mudar atitudes e comportamentos das pessoas em relação ao meio ambiente. / São Cristóvão, SE
74

Dinâmica ambiental e derivações antropogênicas na planície costeira entre as desembocaduras dos rios Sergipe e Vaza-Barris

Menezes, Rodrigo da Silva 26 February 2013 (has links)
Deutsch Akademischer Austausch Dienst / The process of occupation of the coastal areas in Sergipe, as in Brazil, has intensified in recent decades as a result of the implementation of public policies for housing and tourism, consolidated with the construction of infrastructure responsible for generating social conflicts and deep environmental impacts. Among other objectives, the present study aimed to analyze the natural elements of geographic stratum and socioeconomic aspects of the coastal plain between the rivers Sergipe and Vaza Barris from the 1980s, in order to contribute to regional planning in this important environmental area fragility in the city of Aracaju. For characterization purposes, it has become essential to the adoption of methodological procedures associated with the different stages of technical jobs, which consisted of bibliographic and cartographic secondary data and field work. The results of this study show that in the landscape of the city of Aracaju, the coastal plain is the largest unit of geomorphic expression sand, extending for approximately 21 km between the estuaries of the Sergipe and Vaza Barris. Spatial representation of the neighborhoods it covers, such as the Coroa do Meio, Atalaia, Aeroporto, Farolândia and Zona de Expansão shows a marked degree of urbanization in the coastal plain, inheriting the older neighborhoods with consolidation, which have a significant density revealed in last Census, 2010; across the plain totaling a population contingent of 28,988 inhabitants. This way, the intense speculation responsible for direct environmental impacts and associated tourism as a transforming agent of the geographic space of the coastal plain, makes this area a fragmented territory, where the production of vertical and horizontal condominiums and housing projects, particularly in the area of Expansion, away from the main center and outside the consolidated urban fabric, this translates as a new central zone with key role in forging the link between users and urban space as constituting a central city of a new born, as this area is 40% Aracaju of the territory. What one finds, finally, is that there are areas that have been neglected by capital and real estate by state action, like the draft Coastal Management, Master Plan and Orla, because due to this, the upgrading of these places is by reordering their functions and the construction of new arrangements of an urban structure deficit. / O processo de ocupação dos espaços costeiros em Sergipe, como no Brasil, intensificou-se nas últimas décadas em decorrência da implantação de políticas públicas voltadas para habitação e turismo, consolidadas com a construção de infraestruturas responsáveis pela geração de contrastes sociais e de impactos ambientais profundos. Dentre outros objetivos, o presente trabalho visou analisar os elementos naturais do estrato geográfico e os aspectos socioeconômicos da planície costeira entre as desembocaduras dos rios Sergipe e Vaza Barris, a partir da década de 1980, na perspectiva de contribuir para o ordenamento territorial nessa importante área de fragilidade ambiental no município de Aracaju. Para caracterização dos objetivos, tornou-se indispensável à adoção de procedimentos metodológicos associados a diferentes etapas com emprego de técnicas, que consistiram em levantamentos bibliográficos e cartográficos de dados secundários e trabalho de campo. Os resultados desse estudo mostram que na paisagem do município de Aracaju, a planície costeira é a unidade geomorfológica de maior expressão areal, com extensão em torno de 21 km entre os estuários dos rios Sergipe e Vaza Barris. A representação espacial dos bairros em que abrange, tais como Coroa do Meio, Atalaia, Aeroporto, Farolândia e Zona de Expansão evidencia um acentuado grau de urbanização na planície costeira, herdando dos bairros com consolidação mais antiga, que apresentam uma densidade demográfica significativa revelada no último Censo de 2010; totalizando no conjunto da planície um contingente populacional de 28.988 habitantes. Assim, a intensa especulação imobiliária responsável por impactos ambientais diretos e o turismo associado como agente transformador do espaço geográfico da planície costeira, torna essa área num território fragmentado, em que a produção de condomínios verticais e horizontais e conjuntos habitacionais populares, sobretudo na zona de Expansão, distante do centro principal e fora da malha urbana consolidada, traduzem essa zona como uma nova centralidade com papel fundamental na criação de laços entre usuários e espaço urbano se constituindo como lugar central de uma nova cidade que nasce, já que esta área corresponde a 40% do território aracajuano. O que se constata, por fim, é que existem áreas que foram esquecidas pelo capital imobiliário e pela ação do Estado, a exemplo dos projetos de Gerenciamento Costeiro, Plano Diretor e Orla, pois devido a isso, a revalorização desses lugares passa pela reordenação de suas funções e na construção de novos arranjos de uma estrutura urbana deficitária.
75

Avaliação da sustentabilidade ambiental dos fragmentos de maciços florestais da planície costeira e baixa encosta do município de Bertioga (SP) / Evaluation of the environmental sustainability of massive forestry fragments of the coastal plain and lower slopes of Bertioga (SP)

Jaime Enrique de Jesus Badel Mogollón 01 November 2012 (has links)
A zona costeira paulista alterna extensas zonas de grande diversidade de biótopos, com outras de intensa degradação ambiental. Essas características são observadas no município de Bertioga e seus maciços florestais, localizados entre as bacias hidrográficas dos rios Itaguaré e Guaratuba. Por suas características especiais, essas bacias em conjunto receberam a denominação de Sistema Bertioga. Este trabalho pretendeu mapear o panorama da região sob a perspectiva do planejamento ecológico, com a finalidade de dar elementos teóricos e práticos para proteger, reparar e/o desenvolver a natureza e a paisagem cênica desse território. Nesse contexto foi avaliada a sustentabilidade ambiental desse sistema, a partir da análise de risco ecológico e a sensibilidade às mudanças ambientais dos diferentes ecótopos presentes. Para atingir essa meta, foi elaborado um inventário dos recursos naturais do território (biológicos, climáticos, hídricos, edáficos) para todo o sistema, e, com esses elementos, estabelecer um zoneamento ambiental do território, segundo critérios de proteção, reparação e desenvolvimento (manejo) para as diferentes formações vegetais. Foi realizado um refinamento espacial tanto dos ambientes sedimentares como dos ecótopos estudados, e foi quantificado o grau de artificialização do sistema. Um cruzamento dessa informação permitiu propor um sistema de classificação da cobertura vegetal baseado nos grupos funcionais observados. Com base nessa classificação, foi feito um agrupamento das geoformas que ajudasse a entender sua incidência sobre a disposição espacial dos ecótopos. Foi possível realizar uma primeira aproximação sobre o funcionamento hidráulico do sistema, e sugerir as características do pulso hidrossedimentológico que rege o mesmo. Por outra parte, foram confeccionados mapas probabilísticos das características físico-químicas v das águas subsuperficiais do sistema, com base na medição do lençol freático em uma série temporal. Foram definidas as características das águas superficiais e sua incidência no sistema. Foram confeccionados mapas probabilísticos dos diferentes tipos de solos, com os quais foram definidas algumas linhas gerais de sua evolução e os elementos críticos que afetariam sua conservação, tanto do ponto de vista da estabilidade da sua estrutura superficial como de suas características físico-químicas. Por fim, com base em toda a informação compilada foi possível propor uma mapa de objetivos ambientais zonificados, classificados em Zonas Prioritárias para a preservação do Meio Ambiente e em Zonas Preferenciais para o desenvolvimento equilibrado do Meio Ambiente. / The São Paulo coastal zone alternates extensive zones of great diversity of biotopes with others intensively degradated. These characteristics are observed in the municipality of Bertioga and its forest regions localized among Itaguaré and Guaratuba river basins. Due to their special characteristics these basins are denominated Bertioga System. The aim of this work was to map the region scenario under the perspective of ecological planning in order to give the theoretical and practical elements to protect, repair and/or develop the nature and the landscape of this territory. In this context, the environmental sustainability of the system was evaluated using the ecological risk analysis and the sensibility to environmental changes to the different ecotopes. An inventory of the territory natural resources for all the system was performed (biologic, climatic, hydric, edaphic), from which an environmental zone division of the territory following criteria of protection, reparation and development (management) for all the vegetal formations. A spatial refinement of both sedimentary environment and ecotopes was performed, as well as the quantification of the artificialization grade of the system. An exchange of that information was the base to propose a classification system of the vegetation cover based on observed functional groups. A geoshape clustering was performed to help in the understanding of its incidence on the ecotopes spatial disposition. It was possible to perform a first approach about the hydraulic functioning of the system and to suggest the hidrosedimentological pulse characteristics that rule the system. On the other hand, probabilistic maps of the physical and chemical characteristics of the subsuperficial waters of the system were made, on the basis of the freatic level in a temporal vii series. The characteristics of the superficial waters and their incidence on the system were also defined. Probabilistc maps of soil types were made, which were used to define some general lineaments about their evolution and the critical elements that could affect its conservation from two points of view: superficial structure stability, and physical and chemical characteristics. Finally, a zone division map of ambient objectives was proposed. Those ambient objectives were classified in Prioritary Zones for the preservation of the environment and Preferential Zones for the balanced development of the environment.
76

Unidades demonstrativas de restauração ecológica através de técnicas nucleadoras: Floresta Estacional Semidecidual, Cerrado e Restinga / Ecological Restoration Demonstrative Units using Nucleation Techniques: Seasonal Semidecidual Forest, Brazilian Savanna and Coastal Plain Vegetation

Fernando Campanhã Bechara 06 July 2006 (has links)
Refazer ecossistemas de forma artificial representa um desafio de iniciar um processo de sucessão o mais semelhante possível aos processos naturais. A recuperação ambiental tem se baseado no modelo da silvicultura tradicional, plantandose árvores sob espaçamento 3 x 2 m, em área total, com altos insumos de implantação/manutenção, e gerando-se bosques desenvolvidos em altura, porém com baixa diversidade de formas de vida e regeneração. Técnicas nucleadoras de restauração formam microhabitats em núcleos propícios para a chegada de uma série de espécies de todas as formas de vida, que num processo de aceleração sucessional, irradiam diversidade por toda a área. As técnicas foram implantadas em áreas piloto de um hectare, denominadas “Unidades Demonstrativas” (UDs). As UDs foram montadas em Floresta Estacional Semidecidual (Capão Bonito-SP), Cerrado (Santa Rita do Passa Quatro-SP) e Restinga (Florianópolis-SC). Na primeira UD, com um ano de idade, as técnicas nucleadoras introduziram 1.603 mudas de 148 espécies nativas, dentre 84 espécies arbóreas (883 mudas), 12 arbustivas (124 mudas), 30 herbáceas (242 mudas), 20 trepadeiras (260 mudas) e 2 bromeliáceas (3 mudas), além de 94 mudas de hábito indeterminado. Entre as espécies, ocorreram 69 zoocóricas, 32 autocóricas e 29 anemocóricas, além de 21 plantas indeterminadas. Desconsiderando-se as 47 espécies arbóreas implantadas por mudas, houve introdução de: 25% de arbóreas, 8% de arbustos, 20% de ervas, 14% de lianas e 1% de bromeliáceas. Na UD de Cerrado, apesar de impactada por gado, aos dois anos de idade, foram introduzidos 354 indivíduos de 31 espécies nativas. Destas, 39% foram espécies arbóreas, 13% arbustivas, 16% herbáceas, 16% lianas e 16% indeterminadas. Foram registradas 35% de espécies zoocóricas, 29% de anemocóricas, 19% de autocóricas e 16% de plantas com síndrome indeterminada. Na UD de Restinga, foram detectadas, aos dois anos e meio de idade, 180 espécies de 108 gêneros e 55 famílias. As técnicas nucleadoras resultaram num custo experimental estimado em torno de 34% mais barato em relação ao modelo tradicional que varia em torno de R$ 5.500,00 reais/ha. O uso da nucleação aumentou nitidamente a eficiência da restauração ecológica. Foi restituída a diversidade, não só em seu aspecto estrutural, mas considerando-se também os diferentes nichos, formas e funções, formando um mosaico de ambientes e permitindo uma maior dinâmica das comunidades. No atual estágio de conhecimento, é importante a definição de qual paradigma almejamos para a restauração de nossas florestas: cultivar plantações de árvores nativas ou permitir e acelerar a sucessão natural? O novo paradigma das técnicas nucleadoras, ao contrário dos modelos tradicionais de recuperação que apenas satisfazem exigências legais, promovem a restituição de produtores, consumidores e decompositores, gerando a conservação efetiva dos ecossistemas, e assumindo, desta forma, um compromisso ético com as futuras gerações. / To remake ecosystems of artificial form represents a challenge to initiate a process of the possible most similar succession to the natural processes. The environmental recuperation has based on the model of traditional forestry, standing trees under 3 x 2 m spacing, in total area, with high implantation/ maintenance inputs, and generating forests developed in height, however with low diversity of forms of life and regeneration. Restoration nucleation techniques form microhabitats in nuclei propitious for the arrival of a series of species of all the life forms that in a process of sucessional acceleration, radiate diversity for all the area. The techniques had been implanted in pilot areas of one hectare, called "Demonstrative Units" (UDs). The UDs had been mounted in seasonal semidecidual forest (Capão Bonito-SP), Brazilian savanna (Santa Rita do Passa Quatro-SP) and coastal plain vegetation (Florianópolis-SC). In the first UD, with one year of age, the nucleation techniques had introduced 1,603 seedlings of 148 native species, amongst 84 arboreal species (883 seedlings), 12 shrubs (124 seedlings), 30 herbaceous ones (242 seedlings), 20 lianas (260 seedlings) and 2 bromelias (3 seedlings), in addition to 94 seedlings of indeterminate habit. Among the species, 69 zoochore, 32 autochore and 29 anemochore had occurred, plus 21 indetermined plants. Disrespecting the 47 arboreal species implanted by traditional seedlings, there was introduction of: 25% of arboreal, 8% of shrubs, 20% of herbaceous, 14% of lianas and 1% of bromelias. In Brazilian savanna UD, although affected by cattle when two years of age, 354 individuals of 31 native species had been introduced. Of these, 39% had been arboreal species, 13% shrubs, 16% herbaceous, 16% lianas and 16% indetermined. There had been registered 35% of zoochore species, 29% of anemochore, 19% of autochore and 16% of plants with indetermined syndrome. In coastal plain vegetation UD, in two years and half of age, 180 species of 108 genus and 55 families had been detected. The nucleating techniques had resulted cheaper in an esteemed experimental cost around 34% in relation to the traditional model that varies around R$ 5,500.00 reais/ha. The use of the nucleation clearly increased the efficiency of the ecological restoration. The diversity not only restituted its structural aspect, but also the different niches, forms and functions, forming an environment mosaic and allowing a dynamic growth of the communities. In the current period of knowledge, is important the definition of which paradigm we wish for the restoration of our forests: to cultivate plantations of native trees or to allow and to speed up the natural succession? The new paradigm of the nucleation techniques, in contrast to the traditional models of recovery that only satisfy legal requirements, replenishes the producers, consumers and decompositors, promoting the conservation of the ecosystems, and adopting an ethical commitment with the future generations.
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As abordagens sistêmica e do equilíbrio dinâmico na análise da fragilidade ambiental do litoral do Estado de São Paulo: contribuição à geomorfologia das planícies costeiras / Systemic approaches and the dynamic equilibrium in the analysis of environmental fragility of the coast of the state of S Paulo: contribution of geomorphology of coastal plains

Marisa de Souto Matos Fierz 10 December 2008 (has links)
A presente pesquisa tem como objetivo principal avaliar, por meio da abordagem sistêmica e do equilíbrio dinâmico, as diferenças de configurações geológicas e geomorfológicas e de fragilidade nos variados compartimentos geomorfológicos ao longo das planícies costeiras na enseada da Fortaleza, em Ubatuba, litoral norte de São Paulo e região de Peruíbe-Itanhaém, litoral centro-sul de São Paulo. Essas diferenças de configurações morfológicas são resultantes de processos pretéritos e do arcabouço geológico que sustentam as formas manifestadas na paisagem, moldadas pelos processos que atuam como agentes modeladores e de manutenção do equilíbrio dinâmico dessas formas. O equilíbrio dinâmico, nos moldes ecogeográficos de Tricart (1977), é mantido pela cobertura vegetal que pode manter constantes os processos de morfogênese e pedogênese ao longo da planície costeira que constituída de material friável, areias finas a muito finas que lhes conferem, a princípio, um caráter de fragilidade intrínseca. O equilíbrio dinâmico nos moldes geomorfológicos de Hack (1960, 1965) é mantido pela variação da resistência dos materiais que compõem o relevo, sustentando as formas. Essas duas abordagens auxiliaram na determinação da fragilidade ambiental, que é identificada e representada, sobretudo, pelas variações de resistência entre os diversos compartimentos ou subsistemas geomorfológicos mapeados ao longo da planície. Entretanto, em alguns trechos da planície costeira, sobretudo no litoral sul, onde o solo do tipo espodossolo apresenta horizonte B espódico também denominado, nesta tese, de fragipã (?), cuja principal característica é de caráter endurecido pela composição de ácidos húmicos e fúlvicos, retidos ali pelo processo de podzolização. Nestes trechos, os testes de resistência resultaram em poucos impactos de penetração ou nulos. O horizonte B espódico rígido, destarte a classificação da fragilidade ambiental obteve diversidades influenciadas pelas características desses trechos de espodossolos e por apresentarem interferências diretas nos processos de mudanças dos níveis topográficos. / The principal aim of this research, based on the Systems Approach and on the Dynamic Equilibrium, is to evaluate geological and geomorphologic different configurations and environmental fragility on the several geomorphologic topographic features in the coastal plains of Fortaleza bay in Ubatuba, located in the north coast of São Paulo and Peruíbe-Itanhaém area, located in center-southern coast of the São Paulo State.These morphological configurations differences are result of the geologic past processes and the geologic structure that sustain the stamped landscapes forms by active processes that behave as modeling agents and of maintenance of the dynamic equilibrium of this forms.The dynamic equilibrium by ecogeography principles of Tricart (1977) is maintained by the vegetal cover that prolong constant the process of morphogenesis and pedogenesis for all coastal plain that is mainly formed by material, thin to very thin sand particles that gives the region character of intensive fragility.The dynamic equilibrium on the geomorphologic models of Hack (1960, 1965) is maintained by the materials resistance variation that composes the reliefs forms. These both examples help in the determination of the environmental fragility that is identified and represented, mainly by the variations of the resistance among the various compartments geomorphologic or subsystems mapped throughout coastal plain. In some parts of the coastal plain, mainly in the south shore, where the kind of soil is Espodossoil presents level B espodic, also denominated as fragipã (?), which the principal characteristic is present by the character hardened by the composition of the humic and fulvic acids, retained there by the podzolization process. In these places the resistance tests resulted in few or null impacts penetration. The hardened level B espodic, regardless classification of the environmental fragility, showed direct interferences in the process of the changes on the topographic levels.
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QUANTIFYING CURRENT SEDIMENT DEPOSITION, LEGACY SEDIMENTS, AND PRE-IMPOUNDMENT VERTICAL ACCRETION AND CARBON DYNAMICS FOLLOWING DAM REMOVAL IN A RECENTLY RESTORED TIDAL FRESHWATER WETLAND

Davis, Melissa J 01 January 2017 (has links)
Damming disrupts natural sediment flow to downstream resulting in legacy sediment accumulation. Legacy sediments have been well investigated in streams throughout the Piedmont region; however, there is no research of legacy sediments following dam removal in low-gradient Coastal Plain streams. Research objectives were to: characterize legacy sediments in a low-gradient stream restoration, quantify pre-impoundment accretion and carbon dynamics, and assess current sediment deposition rates via 14C analyses within sediment cores and sediment collection tiles. Carbon accumulation and accretion rates of modern tidal sediment have reached that of the tidal relic benchmark and current sediment deposition rates are similar between the natural reference and restored tidal wetlands. At this site, the pattern of legacy sediment accumulation and stream incision was reversed relative to previous studies in higher gradient systems. Results suggest in dam impacted Coastal Plain streams, legacy sediment may become a benefit rather than a liability for downstream tidal wetlands.
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Physical and Hydrologic Responses of an Intensively Managed Loblolly Pine Plantation to Forest Harvesting and Site Preparation

Miwa, Masato 30 September 1999 (has links)
The Southeastern Lower Coastal Plain wet pine flats include thousands of acres of jurisdictional wetlands that are economically, socially, and environmentally important. These highly productive forests have been intensively managed as pine plantations for the past few decades. More recently, harvesting and site preparation practices have become a concern among natural resource managers because intensive forestry practices may alter soil physical properties and site hydrology. These alterations could decrease seedling survival, growth, and future site productivity. However, the effects of soil disturbance on long-term site productivity and the effects of amelioration techniques on site hydrology are uncertain. The overall objectives of this study were (1) to characterize disturbed forest soil morphology and physical properties, (2) to assess their impact on the processes that control site hydrology and site productivity, (3) to determine effects of harvesting and site preparation on site hydrology, specifically on the overall hydrological balance and on spatial and temporal patterns of surface water storage. The study site is located in an intensively managed loblolly pine (Pinus taeda L.) plantation in the lower coastal plain of South Carolina. This study was established in winter 1991, and dry- and wet-weather harvesting treatments were installed in summer 1993 and winter 1994, respectively. Bedding and mole channel/bedding treatments were installed in both dry- and wet-harvested plots in fall 1995. Soil profiles were described for a recently disturbed, deeply-rutted area, and 2-year-old deeply-rutted and churned areas, bedded and undisturbed areas. Intact soil core samples and composite loose soil samples were collected from each morphological section for soil physical characterizations. Automated weather station and wells were used to collect continuous climatic and surface water level data since 1996. Surface water levels were monitored monthly on a 20 x 20 m grid of 1-m wells since 1992. Total groundwater heads were determined from differential piezometer measurements at high and low elevation places in each treatment plot. Soil profile descriptions and soil physical property measurements indicated that significant amounts of organic debris were incorporated into the surface horizons, and subsurface soil horizons showed significant soil structural changes and increased redoximorphic features caused by soil disturbance. The disturbed soil layers in recently created traffic ruts consisted of exposed and severely disturbed subsurface soils, but this layer was naturally ameliorated 2 years after the disturbance. Bedding site preparation had little amelioration effects on the physical properties of surface soil horizons because the surface horizons already had some incorporation of organic debris. Overall, the main consequence of bedding in a disturbed wet site was to increase the aerated soil volume. The bedding appeared to have little effect on disturbed subsurface horizons. Groundwater head in the study site was constantly higher than -25 cm during the study period, which caused groundwater inflow when the surface water level was low. Frequent fluctuation of the surface water level and constant water supply from the groundwater probably explain the high productivity of the study site. Results of the annual water balance showed that surface soil water storage changes were very small, and annual precipitation and potential evapotranspiration were approximately equal. Silvicultural practices and minor topography on the study site had significant effects on the water balance because they influenced surface water level. Surface water hydraulic gradient evaluation and multivariate cluster analysis indicated that micro-site hydrology and water flow patterns were significantly altered by wet-weather harvesting and bedding site preparation, but overall site hydrology was not altered. Evaluation of predicted surface water level indicated that micro-topography and precipitation patterns had significant influences on surface water levels during the site establishment period. These results revealed that the hydrologic components of wetland delineation are complex in the wet pine flatwoods. / Ph. D.
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A vegetation classification and description of five wetland sysems and their respective zones on the Maputuland Coastal Plain

Pretorius, Mathilde Luïse 14 May 2013 (has links)
The Maputaland Coastal Plain in Kwa Zulu-Natal is covered by aeolian sands . According to the national wetland delineation manual delineating wetlands in this area is complex due to problematic wetland soils. The aim of this study was to classify and describe the vegetation of the different zones of the wetland systems to determine the main drivers of the plant communities. The understanding of these complex ecosystems could assist in wetland delineation. Twenty wetlands from five wetland systems were surveyed. The vegetation zones of each wetland were sampled and basic environmental data were collected. The results from this study indicate that different plant species assemblages are characteristic for the wetland zones. However, zone delineation using vegetation composition varies between the different wetland systems, and should be evaluated according to the system in question. The major determinants of the vegetation communities in wetlands on the MCP are the substrate type and hydrological regime / Environmental Sciences / M.Sc. (Environmental Management)

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