Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta dissertação consiste de dois capítulos, cada um correspondendo a um estudo realizado de modo independente. Em um córrego de Mata Atlântica, Rio de Janeiro, Brasil, foram estudados efeitos de herbívoros e de controles ambientais no perifíton. No primeiro trabalho foram testados os efeitos do camarão Potimirim glabra, um engenheiro do ecossistema, nos parâmetros metabólicos de comunidades perifíticas (Produção, Respiração, Metabolismo Líquido da Comunidade e razão Produção:Respiração). O tratamento de inclusão de Potimirim produziu resultados inversos aos esperados, com aumento da clorofila e massa seca das comunidades perifíticas, levantando dúvida com relação à eficácia dos tratamentos. Nenhuma das variáveis metabólicas esteve relacionada aos tratamentos. Considera-se que efeitos artefato da gaiola utilizada na inclusão dos camarões podem ter prejudicado o efeito esperado de remoção de material pelos camarões. Os resultados podem indicar, entretanto, que para o efeito de herbívoros os parâmetros clorofila e massa seca sejam mais sensíveis e variáveis que os metabólicos para as comunidades estudadas. São recomendados futuros trabalhos com metodologias que reduzam os efeitos artefato, tais como exclusão de herbívoros com cercas elétricas. No segundo trabalho, foram estudados os estoques, a distribuição e os controles da biomassa perifítica para o córrego. Entre os substratos estudados, a areia apresentou os maiores estoques, com 5 vezes mais clorofila e 20 vezes mais massa seca que os substratos pedra e folha. Diferenças entre trechos com diferentes densidades do camarão herbívoro Potimirim glabra revelaram para o substrato pedra menores valores de massa seca para os locais onde o camarão é mais numeroso. Entre as variáveis ambientais, apenas a profundidade esteve relacionada aos dados de biomassa nos substratos pedra e areia. A comparação dos dados deste estudo com trabalhos anteriores pode indicar que distúrbios provocados por enchentes podem alterar os estoques e os padrões de distribuição para este córrego. / This dissertation consists of two chapters, each corresponding to an independent study. In an Atlantic Rainforest stream, Rio de Janeiro, Brazil, the effects of herbivores and of environmental controls on periphyton were studied. In the first experiment I tested the effects of the shrimp Potimirim glabra, an ecosystem engineer, on the metabolic parameters of periphytic communities (Production, Respiration, Net Daily Metabolism and Production:Respiration ratio). The Potimirim inclusion treatments produced results opposite to the expected, with higher chlorophyll and dry mass of the periphytic communities. This lead to doubt of the efficacy of the treatments. None of the metabolic variables was related to the treatments. It is considered that artificial effects of the cage used in the shrimp inclusion may have changed the expected effect of material removal by the shrimps. The results may hint, however, that the chlorophyll and dry mass parameters may be more sensitive to and variable with the effects of herbivores than the metabolic parameters in the studied communities. Future work is recommended with methods that reduce artificial effects, such as herbivore exclusion using electric fences. In the second experiment, stocks, distribution and controls of periphytic biomass were studied for the stream. Among the studied substrates, sand presented the highest stocks, with 5 times more chlorophyll and 20 times more dry mass than the rock and leaf substrates. Differences among reaches with different densities of the herbivore shrimp Potimirim glabra revealed for the stone substrate smaller dry mass values in the reaches where the shrimp is more abundant. Among environmental variables, only depth was related to biomass, in the substrates rock and sand. The comparison of data in this study with previous work may hint that disturbances caused by spates may change stocks and distribution patterns for this stream.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta dissertação consiste de dois capítulos, cada um correspondendo a um estudo realizado de modo independente. Em um córrego de Mata Atlântica, Rio de Janeiro, Brasil, foram estudados efeitos de herbívoros e de controles ambientais no perifíton. No primeiro trabalho foram testados os efeitos do camarão Potimirim glabra, um engenheiro do ecossistema, nos parâmetros metabólicos de comunidades perifíticas (Produção, Respiração, Metabolismo Líquido da Comunidade e razão Produção:Respiração). O tratamento de inclusão de Potimirim produziu resultados inversos aos esperados, com aumento da clorofila e massa seca das comunidades perifíticas, levantando dúvida com relação à eficácia dos tratamentos. Nenhuma das variáveis metabólicas esteve relacionada aos tratamentos. Considera-se que efeitos artefato da gaiola utilizada na inclusão dos camarões podem ter prejudicado o efeito esperado de remoção de material pelos camarões. Os resultados podem indicar, entretanto, que para o efeito de herbívoros os parâmetros clorofila e massa seca sejam mais sensíveis e variáveis que os metabólicos para as comunidades estudadas. São recomendados futuros trabalhos com metodologias que reduzam os efeitos artefato, tais como exclusão de herbívoros com cercas elétricas. No segundo trabalho, foram estudados os estoques, a distribuição e os controles da biomassa perifítica para o córrego. Entre os substratos estudados, a areia apresentou os maiores estoques, com 5 vezes mais clorofila e 20 vezes mais massa seca que os substratos pedra e folha. Diferenças entre trechos com diferentes densidades do camarão herbívoro Potimirim glabra revelaram para o substrato pedra menores valores de massa seca para os locais onde o camarão é mais numeroso. Entre as variáveis ambientais, apenas a profundidade esteve relacionada aos dados de biomassa nos substratos pedra e areia. A comparação dos dados deste estudo com trabalhos anteriores pode indicar que distúrbios provocados por enchentes podem alterar os estoques e os padrões de distribuição para este córrego. / This dissertation consists of two chapters, each corresponding to an independent study. In an Atlantic Rainforest stream, Rio de Janeiro, Brazil, the effects of herbivores and of environmental controls on periphyton were studied. In the first experiment I tested the effects of the shrimp Potimirim glabra, an ecosystem engineer, on the metabolic parameters of periphytic communities (Production, Respiration, Net Daily Metabolism and Production:Respiration ratio). The Potimirim inclusion treatments produced results opposite to the expected, with higher chlorophyll and dry mass of the periphytic communities. This lead to doubt of the efficacy of the treatments. None of the metabolic variables was related to the treatments. It is considered that artificial effects of the cage used in the shrimp inclusion may have changed the expected effect of material removal by the shrimps. The results may hint, however, that the chlorophyll and dry mass parameters may be more sensitive to and variable with the effects of herbivores than the metabolic parameters in the studied communities. Future work is recommended with methods that reduce artificial effects, such as herbivore exclusion using electric fences. In the second experiment, stocks, distribution and controls of periphytic biomass were studied for the stream. Among the studied substrates, sand presented the highest stocks, with 5 times more chlorophyll and 20 times more dry mass than the rock and leaf substrates. Differences among reaches with different densities of the herbivore shrimp Potimirim glabra revealed for the stone substrate smaller dry mass values in the reaches where the shrimp is more abundant. Among environmental variables, only depth was related to biomass, in the substrates rock and sand. The comparison of data in this study with previous work may hint that disturbances caused by spates may change stocks and distribution patterns for this stream.

Helicopters have now become an essential part for civil and military activities, for the next few years a significant increase in the use of this mean of transportation is expected. Unlike many fixed-wing aircraft, helicopters have no need to be pressurized due to their operating at low altitudes. The Environmental Control Systems (ECS) commonly used in fixed-wing aircraft are air cycle systems, which use the engine compressor’s bleed flow to function. These systems are integrated in the aircraft from inception. The ECS in helicopters is commonly added subsequently to an already designed airframe and power plant or as an additional development for modern aircraft. Helicopter engines are not designed to bleed air while producing their rated power, due to this a high penalty in fuel consumption is paid by such refitted systems. A detailed study of the different configurations of ECS for rotorcraft could reduce this penalty by determining the required power resulting from each of the system configurations, and therefore recommend the most appropriate one to be implemented for a particular flight path and aircraft. This study presents the conducted analysis and subsequent simulation of the environmental control system in a selected representative rotorcraft: the Bell206L-4. This investigation seeks to optimize the rotorcraft’s power consumption and energy waste; by taking into consideration the cabin heat load. It consequently aims to minimize these penalties, achieving passenger comfort, an optimally moist air for equipment and a reduction in the environmental impact. For the purpose of this analysis a civil aircraft was chosen for a rotary-wing type. This helicopter was analysed with different air-conditioning packs complying with the current airworthiness requirements. These systems were optimized with the inclusion of different environmental control models, and the cabin heat load model, which provided the best air-conditioning for many conditions and mission scopes, thus reducing the high fuel consumption in engines and hence the emission of gases into the environment. Each of the models was computed in the Matlab-simulink® software. Different case studies were carried out by changing aircraft, the system’s configurations and flight parameters. Comparisons between the different systems and sub-systems were performed. The results of these simulations permitted the ECS configuration selection for optimal fuel consumption. Once validated the results obtained through this model were included in Rotorcraft Mission Energy Management Model (RMEM), a tool designed to predict the power requirements of helicopter systems. The computed ECS model shows that favourable reductions in fuel burn may be achievable if an appropriated configuration of ECS is chosen for a light rotorcraft. The results show that the VCM mixed with engine bleed air is the best configuration for the chosen missions. However, this configuration can vary according to the mission and environment.

Syftet med studien är att analysera det praktiska tillämpandet av miljöbalken inom lantbruksområdet i form av den miljötillsyn som utförs avkommunala tillsynsmyndigheter gentemot lantbrukare med anmälnings- eller tillståndspliktig verksamhet. Studien avser att kartlägga erfarenheteroch upplevelser av den operativa delen av miljölagstiftning samt ifall förändringar av densamma efterfrågas. I studien har semi-struktureradeintervjuer genomförts med sju respondenter i Östergötland. Resultatet av intervjuerna analyseras utifrån de teman som identifierats, för attundersöka erfarenheter och upplevelser av miljötillsynen. Resultaten visar att det som är av störst betydelse för lantbrukarna är möjligheterna tillkommunikation och dialog samt att inspektörernas förståelse för verksamhetens förutsättningar måste öka. Även skillnader som uppstår på grundav tolkningsfriheten för respektive tillsynsmyndighet, måste enligt lantbrukarna begränsas för att bli enhetlig nationellt sett. Vi identifierar att detfinns en förtroendeklyfta mellan lantbrukare och inspektörer vilket kan påverka upplevelsen av miljötillsynen. Arbete med att ta fram åtgärder föratt minska denna klyfta bör ske kontinuerligt för att säkerställa en effektivare miljötillsyn och för att skapa ett ökat förtroende mellan lantbrukareoch inspektörer. / The purpose of the study is to analyze the practical application of the Environmental Code in the field of agriculture in the form of environmentalinspections carried out by municipal regulatory authorities vis-à-vis farmers with a notification or authorization requirement. The study intends tomap the experiences of the operational part of environmental legislation and if changes to it are required. In the study, semi-structured interviewswere conducted with seven respondents in the county of Östergötland. The results of the interviews are analyzed based on the themes identified toinvestigate the experiences of environmental supervision. The results show that the most important thing for farmers is the possibility ofcommunication and dialogue, and that the inspectors' understanding of the business conditions must increase. Even differences arising from thefreedom of interpretation of the respective supervisory authorities, according to farmers, must be limited to being uniform nationally. We identifythat there is a trust gap between farmers and inspectors, which can affect the experience of environmental oversight. Work to develop measures toreduce this gap should be done continuously to ensure more effective environmental inspections and to increase trust between farmers andinspectors.