6 resultados para manejo de cuencas hidrográficas

em Universidade Federal do Rio Grande do Norte(UFRN)


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In northeastern Brazil, Octopus insularis is the most commercially important cephalopod species and its capture has been performed for several years by the lobster fishermen in the region. In order to obtain information about the reproductive biology, 1108 specimens were collected between November 2009 and September 2011 in the landings and fish markets of Rio do Fogo (RN). For each specimen the mantle length (CM) and total fresh weight (PT) were recorded. Gonads of 264 males and 295 females were examined macroscopically and histologically to assess sexual maturation and determine reproductive indices. Four reproductive stages were determined for males (immature, maturing, mature and post-mature) and females (immature, early maturing, late maturing and mature). The average of eggs recorded in the female s gonads was 93.820 and 39 was the average of spermatophores found in male Needham s complex. Spermathecae with sperm were found in females with 69 mm CM (immature). Males and females become sexually mature at 64.41 and 98.50 mm of CM, respectively. The weight at sexual maturity was 270 g for males and 630 g for females. The values of the size and weight at sexual maturity found in this study show that males mature at smaller sizes than females. For both sexes the maturation peaks occurred in February and November 2010 and also in September 2011. The periods of maximum reproductive activity lasted about 3 months and it seems to occur every 7 10 months. Only one spent female (stage V) was found and the number of mature females was low. Presumably, mature females migrate to deep waters with complex habitat to protect the offspring, indicating that fishery by snorkeling with maximum depth of 15 meters is not reaches this part of the stock. Finally, it is noticeable the importance of the establishment of management strategies for the exploitation of O. insularis different of the ones used for O. vulgaris, once the species have distinct biological features

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O uso da biodiversidade pelo homem leva a alterações no funcionamento dos ecossistemas, podendo ainda levar a perda de resiliência. Pode-se definir resiliência como a capacidade de um sistema absorver um distúrbio e reorganizar-se, enquanto submetido a mudanças, mantendo a mesma estrutura e funcionamento. Em um sistema social, entende-se como a capacidade dos usuários de recursos naturais de enfrentar e adaptar-se as mudanças nas regras que regem o uso e acesso a estes. Alterações na resiliência, tanto ecológica quanto social, podem ser resultantes das ações de exploração e manejo destes recursos. Assim, torna-se essencial compreender como funcionam as estratégias de manejo e sua interação com a resiliência sócio-ecológica, permitindo a auto-avaliação das ações e possíveis modificações das mesmas. Neste projeto, propõe-se comparar a resiliência sócio-ecológica de três Unidades de Conservação (UCs) de uso sustentável: Reserva de Desenvolvimento Sustentável (RDS) Ponta do Tubarão, localizada no estado do Rio Grande do Norte; e as Reservas Extrativistas do Batoque e Prainha do Canto Verde, ambas localizadas no estado do Ceará. Em cada área de estudo serão escolhidas comunidades pesqueiras, permitindo a comparação entre elas. A partir destas comunidades, alguns aspectos relacionados ao uso dos recursos serão analisados, como atividade pesqueira, dieta e modo de vida. Os dados serão coletados através de questionários semi-estruturados, contendo questões baseadas em aspectos sociais, econômicos e ecológicos. Os resultados obtidos servirão de indicadores para a resiliência ecológica (informações obtidas com base na atividade pesqueira) e social (informações obtidas com base no acompanhamento da dieta e análise do modo de vida). Apesar da similaridade ecológica entre as áreas de estudo, algumas estratégias de manejo distintas em função da categoria da UC podem apresentar diferentes resultados sobre a resiliência sócio-ecológica. Desta forma, compreender como a resiliência sócio-ecológica se comporta, dentro dos sistemas de manejo estudados, permitirá avaliar a influência destes dois tipos de UCs (RDS e RESEX) na promoção da sustentabilidade ecológica e/ou social

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Urban stormwater can be considered as potential water resources as well as problems for the proper functioning of the manifold activities of the city, resulting from inappropriate use and occupation of the soil, usually due to poor planning of the occupation of the development areas, with little care for the environmental aspects of the drainage of surface runoff. As a basic premise, we must seek mechanisms to preserve the natural flow in all stages of development of an urban area, preserving the soil infiltration capacity in the scale of the urban area, comprising the mechanisms of natural drainage, and noting preserving natural areas of dynamic water courses, both in the main channel and in the secondary. They are challenges for a sustainable urban development in a harmonious coexistence of modern developmental, which are consistent with the authoritative economic environmental and social quality. Integrated studies involving the quantity and quality of rainwater are absolutely necessary to achieve understanding and obtaining appropriate technologies, involving both aspects of the drainage problems and aspects of use of water when subjected to an adequate management of surface runoff , for example, the accumulation of these reservoirs in detention with the possibility of use for other purposes. The purpose of this study aims to develop a computer model, adjusted to prevailing conditions of an experimental urban watershed in order to enable the implementation of management practices for water resources, hydrological simulations of quantity and, in a preliminary way, the quality of stormwater that flow to a pond located at the downstream end of the basin. To this end, we used in parallel with the distributed model SWMM data raised the basin with the highest possible resolution to allow the simulation of diffuse loads, heterogeneous characteristics of the basin both in terms of hydrological and hydraulic parameters on the use and occupation soil. The parallel work should improve the degree of understanding of the phenomena simulated in the basin as well as the activity of the calibration models, and this is supported by monitoring data acquired during the duration of the project MAPLU (Urban Stormwater Management) belonging to the network PROSAB (Research Program in Basic Sanitation) in the years 2006 to 2008

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Understanding the historical and ecological relationships which are influent in current biological diversity is one of the most challenging tasks of evolutionary biology. Recent systematics emphasizes the need of integrative approaches to delimit different lineages and species. The northeastern Brazil, mostly placed in Caatinga biome, is characterized by a semi-arid weather, low precipitation and seasonal behavior of rivers. This region is regarded lacking as ichthyological knowledge and one of the most threatened by anthropic activities. Further, will be affected by a massive water diverpsion work that will transfer waters from São Francisco basin, to other major four basins: Jaguaribe, Apodi-Mossoró, Piranhas-Açu and Paraiba do Norte. Loss of diversity and richness, hibridizitation, community interactions changes, population homogenization, changes in water quality and flow regime, are examples of environmental impacts already related with similar works. The present study aims to investigate morphological and molecular variation of Cichlasoma orientale Kullander 1983 and Crenicichla menezesi Ploeg 1991, two cichlid species present in northeastern Brazil basins. Further, the study aims to evaluate the influence of geomorphological and climatic processes in this variation, and point some possible impacts of the artificial connectivity which can be brought by São Francisco interbasin water transfer to their population dynamics. Geometric morphometrics and phylogeographical analysis were used to investigate the populations from three different hydrological regions. Our results showed a significant morphological variation of populations from basins that are involved in the São Franscisco s diversion project, not related to an ancient separation between populations, emphasizing morphological variation which could represent a set of plastic responses to the variable hydrological regime in Northeastern Brazil. The role of plastical responses in naturally variable habitats as well as the potential disturbs that could be brought by the interbasin water transfer works are discussed here. Further, our molecular data allowed us to make inferences about species distribution and their taxonomy, and identification of a potential new species of Crenicichla for São Francisco river basin. Our data also allowed to identify some shared haplotypes for both species, which could be related to lineage sorting scenarios or recent gene flow between populations. However a strong structure in most of the pairwise comparisons between populations for both species was revealed. Climatic events such as Atlantic forest regression during the Pleistocene, sea level fluctuations and dispersion by paleorivers in the mouth of Apodi-Mossoró river, and neotectonic events regulating the connection between drainages are likely to have had a contribution for the actual lineages distribution in northeastern Brazil. Further, analysis of molecular variation (AMOVA and SAMOVA) showed that the actual basin s isolation is an important factor to molecular variation, in spite of the signal of recent contact between some basins. Different genetic diversity patterns between species could be related to multiple historic events of colonization, basins landscapes or biological differences. The present study represents the first effort of integrative systematics involving fish species of northeastern Brazil, and showed important morphological and molecular patterns which could be irrecoverably affected by the artificial connection that might be caused by the São Francisco interbasin water transfer

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Coastal and marine protected areas are created to protect habitat, avoid biodiversity loss, and to help maintain viable fisheries. However, most of these areas in tropical countries occurs in impoverished regions and directly affect the livelihood and survival of coastal communities which directly depend on fisheries and shellfisheries. Therefore, socioeconomic and conservation goals overlap. In this context, fishers should have a central place in resource management. They are critical resource users and their behavior directly affects the system. Shellfish resources are important sources of food, employment and income to fishing communities in Latin America. But despite its widespread use for food and income, there is an urgent need of more research on shellfish management. This research discusses the artisanal fisheries of Venus clam (Anomalocardia brasiliana) (Gmelin, 1791) (Bivalvia: Veneridae) in Brazil, and points out strategies to improve the system. Venus clam is a small and commonly exploited species for food and income on the Brazilian coast. This research was carried out at Ponta do Tubarão Sustainable Development Reserve (Brazilian Northeast coast), where there was no information available about who harvest, where or how much Venus clam has been harvested, despite this resource being exploited for generations. Clam fishery follows the pattern of socio-economic invisibility that general clam exploitation has in Brazil. Methods used were interviews, participatory monitoring and focal follow observation from January 2010 to May 2011. Results include: (a) the identification of shell fishers, (b) how harvest and meat processing are performed (mollusk beds, time spent, gross and net production), (c) the analisis of shell fisher income and their economic sustentability, and (d) the involvement of shell fisher families in data gathering and analyses for the first time. Based on the acquired knowledge, we propose a new institutional arrangement for clam fishery including co-management, fisheries agreement, compensatory arrangements and improvements for the Venus clam value chain such as the establishment of a minimum price for clam meat. This research also includes two other results: a general description for Venus clam harvesting in the Brazilian Northeast coast and a specific discussion about co-management of Venus clam in Brazil. The first one was possible through the meeting of several shell fisherwomen from other states during activities promoted by People of the Tides (PoT) project. PoT was an international initiative aiming to develop coastal communities that depend on mollusk for their livelihood. The second one is a comparison between PoT and Venus clam management at Pirajubaé Marine Extractive Reserve (Santa Catarina). It evaluates the success and failures of these only two initiatives involving co-management of A. brasiliana in Brazil

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Hydrographic basins always exercised a big fascination over humankind that attracted for its scenery beauty or for its richness in natural resources, had been acting in order to modify these important ecosystems without, therefore, considering the possible consequences of these changes. The attributed importance to the coast ecosystems, in eminence to the hydrographic basin of Punaú river and adjacent areas, is had when it s verified the diversity of the ecosystems that contemplate it. Hydrographic basin in evidence in Rio Grande do Norte state, occupies an area of nearly 652.71 km², being it sited in the homogeneous micro-region Litoral Nordeste, with a regional population estimated in nearly 75,188 inhabitants, according to the Anuário Estatístico do Rio Grande do Norte 2004. The region of the researched basin is formed by seven municipal districts related as it follows: Maxaranguape, Pedra Grande, Pureza, Rio do Fogo, São Miguel de Touros, Taipu and Touros, but Maxaranguape, Rio do Fogo, Touros and Pureza have a direct participation in the basin. Basin in study have it lands evaluated according to the agriculturist aptitude by the conventionally methodology practiced in the country, having as objective, then, a compara-tive analysis between the ambient unities, Aeolian littoral and coast tray, identified in the researched area. From the characterization of the physic way of the area in study and owning the kept data, it was proceeded the integrated analysis of the structural elements of the landscape which were evidenced that the fragile areas are associated with the areas of agriculture cultivation, such as the ones of irregular occupation. About the degradation, the ambient diagnostic of the basin indicated that the equivalent to the Aeolian Littoral Ambient Unit correspond to the bigger pledging of the ambient quality, in other words, high ambient fragility, being this result due to the use and occupation of the soil, propitiating this way, vulnerability in the vegetal cover of the area, despite it disposes of a low agriculture cultivation percentage. Already in the Coast Ambient Tray, is emphasized the medium ambient fragility, despite of the high index of cultivated area. In a general way, the total area of the hydrographic basin of Punaú river and adjacent areas presented ambient impacts over the tolerance limit, indicating the necessity of a review of the practices of use and handling of the soil, reforesting of the water courses edges, control of erosion and contamination of the aqueous in the perspective to reduce the effects of the impacts due to the use and occupation of the basin in regard. The present search evaluated the ambient impacts diagnosised in the hydrographic basin of Punaú river and adjacent areas, pointing the causes and the probable consequences of the damages caused by these impacts to the basin ambient. From the analysis of these data, if was possible to become explicit how they are fundamental as key elements in the process of decision taking in the ambient questions