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Especialização individual em três espécies de peixes em um rio intermitente do semiárido brasileiroDuarte, Maria Rita Nascimento 02 February 2016 (has links)
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Previous issue date: 2016-02-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the Neotropical zone the generalist habit is common among fish populations, especially in semi-arid rivers. In these systems, where the availability of food items varies spatially and temporally, it is expected that a more generalist strategy dominates. However, populations classified as generalist may actually be composed of relatively specialist individuals. This study aims at quantifying the use of food resources and understanding the individual contribution to population niche of Hoplias malabaricus, Geophagus brasiliensis and Prochilodus brevis. Four collections were performed at four sites along the Ipanema (PE) River, in April and July 2007 (wet season) and October 2007 and January 2008 (dry season). Sampling was performed at daylight, using gillnets, manual trawls and cast nets. The specimens collected were fixed in 4% formalin and preserved in 70% ethanol. The diet was quantified using the indirect volumetric method, frequency of occurrence and numeric frequency. Spatial patterns of variation in food items between species were evaluated using the Nonmetric Multidimensional Scaling (NMS). The Multi-Response Permutation Procedure (MRPP) was used to test the significance of differences in diet composition between species, sites and sampling periods. The degree of specialization of each individual was calculated using a proportional similarity index. The amplitude and niche overlap ratios were calculated using the Levins and Bolnick indexes. The graphical analysis of Amundsen was performed in order to correlate the diet composition with the selection of specific prey. The species showed a pattern of distribution and segregation in diet between the sampling sites. The MRPP showed that there were significant differences in the diet composition between species (MRPP, A= 0, 61; p= 0, 00). Geophagus brasiliensis specie showed significant differences between site 1 and site 4 (MRPP, A = 0.14; p = 0.03) and site 2 and site 4 (MRPP, A = 0.16 p = 0, 03), the Prochilodus brevis specie between site 1 and site 3 (MRPP, A = 0.28 p = 0.02) and site 1 and site 4 (MRPP, A = 0.11; p = 0.04). The three species present individual specialization in all sampling sites and in both periods of the hydrological cycle. The species Hoplias malabaricus has a population with most experts individuals, with rest of fish as the dominant item, however, with other individuals in the population consuming a high abundance of specific prey. However Geophagus brasiliensis presented a generalist population, with individuals of the population consuming a variety of items, displaying a relatively high component within phenotype. Prochilodus brevis showed a population with varied feeding strategy, presenting degrees of specialization with the contribution of Cyclotela item and generalization, where food items were consumed by more than half of the population. It was observed that individual specialization is highly correlated with niche overlap, indicating that the smaller the overlap the larger the degree of individual specialization. It is important to emphasize that the greatest degree of individual specialization was observed where there was a greater availability of food resources consumed by the populations. / Na região neotropical o hábito generalista é comum em populações de peixes, especialmente em rios do semiárido. Nesses sistemas onde a distribuição dos itens alimentares varia espacial e temporalmente, espera-se que a estratégia generalista predomine entre as espécies. Este estudo objetiva quantificar a utilização de recursos alimentares e compreender a contribuição individual para o nicho populacional em três espécies de peixes, Hoplias malabaricus, Geophagus brasiliensis e Prochilodus brevis. Foram realizadas coletas em quatro pontos ao longo do rio Ipanema (PE) nos meses de abril e julho de 2007 (período chuvoso) e outubro de 2007 e janeiro de 2008 (período seco). As amostragens foram feitas durante o dia, usando redes de arrasto, espera e tarrafa. Os espécimes coletados foram fixados em formol 4% e preservados em álcool 70%. A dieta foi quantificada usando o método volumétrico indireto, frequência de ocorrência e a frequência numérica. Padrões espaciais de variação de itens alimentares para as espécies foram avaliados por meio Escalonamento Multidimensional Não- Métrico (NMS). O Procedimento de Permutações Múltiplas (MRPP) foi utilizado para testar diferenças na composição da dieta entre as espécies, pontos e períodos de amostragem. O grau de especialização de cada indivíduo foi calculado utilizando um índice de similaridade proporcional. A amplitude e sobreposição de nicho foram calculadas utilizando os índices de Levins e Bolnick. Foi realizada a análise gráfica de Amundsen a fim de relacionar a composição da dieta com a seleção de presas específicas. O MRPP mostrou que houve diferenças significativas na composição da dieta entre as espécies (A = 0,61; p = 0,005). Entre os pontos de coleta a espécie Geophagus brasiliensis apresentou diferenças significativas entre o ponto 1 e ponto 4 (MRPP, A = 0,14 e p = 0,03) e ponto 2 e ponto 4 (MRPP, A = 0,16 e p = 0,03), a espécie Prochilodus brevis entre o ponto 1 e ponto 3 (MRPP, A = 0,28 e p = 0,02) e ponto1 e ponto 4 (MRPP, A = 0,11 e p = 0,04). As três espécies apresentaram especialização individual em todos os pontos de coletas e em ambos os períodos de regime hidrológico. A espécie Hoplias malabaricus apresentou uma população com a maioria dos indivíduos especialistas, apresentando resto de peixe como item dominante, porém, com outros indivíduos da população consumindo uma alta abundância de presas especificas. Geophagus brasiliensis apresentou uma população generalista, com indivíduos da população consumindo uma variedade de itens, exibindo um componente relativamente elevado dentre- fenótipo. Prochilodus. brevis mostrou uma população com estratégia de alimentação variada, apresentando graus de especialização com a contribuição do item alimentar Cyclotela e generalização, onde os itens alimentares tinham sido consumidos por mais da metade da população. Observou-se que a especialização individual está correlacionada com a sobreposição de nicho, indicando que, quanto menor sobreposição maior é o grau de especialização individual. É importante ressaltar que o maior grau de especialização individual foi observado onde houve uma maior riqueza de recursos alimentares consumidos pelas populações.
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Ecosystem functioning in streams : Disentangling the roles of biodiversity, stoichiometry, and anthropogenic driversFrainer, André January 2013 (has links)
What will happen to ecosystems if species continue to go extinct at the high rates seen today? Although ecosystems are often threatened by a myriad of physical or chemical stressors, recent evidence has suggested that the loss of species may have impacts on the functions and services of ecosystems that equal or exceed other major environmental disturbances. The underlying causes that link species diversity to ecosystem functioning include species niche complementarity, facilitative interactions, or selection effects, which cause process rates to be enhanced in more diverse communities. Interference competition, antagonistic interactions, or negative selection effects may otherwise reduce the efficiency or resource processing in diverse communities. While several of these mechanisms have been investigated in controlled experiments, there is an urgent need to understand how species diversity affects ecosystem functioning in nature, where variability of both biotic and abiotic factors is usually high. Species functional traits provide an important conceptual link between the effects of disturbances on community composition and diversity, and their ultimate outcomes for ecosystem functioning. Within this framework, I investigated relationships between the decomposition of leaf litter, a fundamental ecosystem process in stream ecosystems, and the composition and diversity of functional traits within the detritivore feeding guild. These include traits related to species habitat and resource preferences, phenology, and size. I focused on disentangling the biotic and abiotic drivers, including functional diversity, regulating ecosystem functioning in streams in a series of field experiments that captured real-world environmental gradients. Leaf decomposition rates were assessed using litter-bags of 0.5 and 10 mm opening size which allow the quantification of microbial and invertebrate + microbial contributions, respectively, to litter decomposition. I also used PVC chambers where leaf litter and a fixed number of invertebrate detritivores were enclosed in the field for a set time-period. The chemical characterisation of stream detritivores and leaf litter, by means of their nitrogen, phosphorus, and carbon concentration, was used to investigate how stoichiometric imbalance between detritivores and leaf litter may affect consumer growth and resource consumption. I found that the diversity and composition of functional traits within the stream detritivore feeding guild sometimes had effects on ecosystem functioning as strong as those of other major biotic factors (e.g. detritivore density and biomass), and abiotic factors (e.g. habitat complexity and agricultural stressors). However, the occurrence of diversity-functioning relationships was patchy in space and time, highlighting ongoing challenges in predicting the role of diversity a priori. The stoichiometric imbalance between consumers and resource was also identified as an important driver of functioning, affecting consumer growth rates, but not leaf decomposition rates. Overall, these results shed light on the understanding of species functional diversity effect on ecosystems, and indicate that the shifts in the functional diversity and composition of consumer guilds can have important outcomes for the functioning of stream ecosystems.
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Processus de la couche limite atmosphérique stable hivernale en vallée alpine / Wintertime Stable Boundary-Layer Processes in Alpine ValleysArduini, Gabriele 06 June 2017 (has links)
La dynamique de la couche limite atmosphérique d'une vallée alpine est influencée par le relief environnant et par l’écoulement de grande échelle qui la surmonte. La paramétrisation de cette circulation atmosphérique requiert donc de caractériser finement ces effets. C'est l’objectif de ce travail de thèse : comprendre l’influence du relief environnant une vallée sur les bilans de masse et de chaleur au travers d’une section de cette vallée, par conditions stables et sèches et lorsque le vent synoptique est faible mais non négligeable. Le travail s’appuie sur des simulations numériques.Plusieurs vallées idéalisées ont tout d’abord été considérées: une vallée infiniment longue (bidimensionnelle) et une vallée tridimensionnelle, qualifiée de supérieure, ouvrant soit sur une plaine (cas “vallée-plaine”), soit sur une autre vallée, qualifiée d’inférieure. Cette seconde vallée est soit plus large (cas “drainage”) ou plus étroite (cas “quasi-stagnation”).Dans les vallées tridimensionnelles, deux régimes principaux ont été identifiés, quelle que soit le cas considéré : un régime transitoire, avant que le vent de vallée (descendant) ne se développe, puis un régime quasi-stationnaire, quand le vent de vallée est complètement développé. La présence d’une vallée inférieure réduit la variation de température le long de la vallée, de sorte que le vent de vallée y est plus faible que dans le cas vallée-plaine. En conséquence, la durée du régime transitoire augmente et est maximum pour le cas quasi-stagnation. Lorsque la vallée inférieure est très étroite, la variation de température peut même changer de signe, conduisant à un vent de vallée montant, de la vallée inférieure vers la vallée supérieure. Durant ce régime transitoire, le taux de refroidissement moyenné sur le volume de la vallée est maximum, sa valeur dépendant du cas considéré. En conclusion, les cas drainage et quasi-stagnation conduisent à une couche limite dans la vallée supérieure plus froide et plus profonde que dans le cas vallée-plaine.Dans le régime quasi-stationnaire, le taux de refroidissement moyenné sur le volume de la vallée est plus faible que dans le régime transitoire et varie peu en fonction du cas considéré. En effet, lorsque la vallée inférieure devient plus étroite, le réchauffement lié aux effets advectifs diminue car la vitesse du vent de vallée diminue, de sorte que la contribution (refroidissante) du flux de chaleur sensible diminue également. La conservation de la masse dans la couche limite de la vallée supérieure est assurée par un équilibre entre la convergence des vents de pente au sommet de la couche limite (alimenté par un courant de retour au-dessus (et en sens inverse) du vent de vallée descendant) et la divergence du vent de vallée, les effets de subsidence loin des parois de la vallée jouant un rôle négligeable.Le cas réaliste de la vallée de l’Arve autour de Passy durant une période d’observation intensive de la campagne de mesures PASSY-2015 a permis de caractériser l’impact des vallées environnant Passy sur les bilans de masse et de chaleur dans la vallée. Une couche d’air froid persistante se forme en fond de vallée, suite à l’advection d’air chaud associée au passage d’une crête anticyclonique au-dessus de l’Europe. Les écoulements le long des vallées tributaires présentent une grande variabilité durant la phase persistante de l’épisode, dépendant de la variabilité de l’écoulement à grande échelle, et ont un impact majeur sur l’intensité de la couche d’air froid et la hauteur de l’inversion qui la surmonte. La forte stratification près du sol conduit à leur décollement au-dessus du fond de vallée, les empêchant d'y pénétrer. L’évolution de l’écoulement à grande échelle durant l’épisode a un profond impact sur la dynamique proche du fond de vallée. Durant la nuit en effet, la canalisation de cet écoulement réduit la variation de température le long de la vallée contrôlant le vent de vallée, favorisant la stagnation de l’air. / Alpine valleys are rarely closed systems, implying that the atmospheric boundary layer of a particular valley is influenced by the surrounding terrain and large-scale flows. A detailed characterisation and quantification of these effects is required in order to design appropriate parameterisation schemes for complex terrains. The focus of this work is to improve the understanding of the effects of surrounding terrain (plains, valleys or tributaries) on the heat and mass budgets of the stable boundary layer of a valley, under dry and weak large-scale wind conditions. Numerical simulations using idealised and real frameworks are performed to meet this goal. Several idealised terrains (configurations) were considered: an infinitely long valley (i.e. two-dimensional), and upstream valleys opening either on a plain (valley-plain), on a wider valley (draining) or on a narrower valley (pooling). In three-dimensional valleys, two main regimes can be identified for all configurations: a transient regime, before the down-valley flow develops, followed by a quasi-steady regime, when the down-valley flow is fully developed. The presence of a downstream valley reduces the along-valley temperature difference, therefore leading to weaker down-valley flows. As a result, the duration of the transient regime increases compared to the respective valley-plain configuration. Its duration is longest for pooling configuration. For strong pooling the along-valley temperature difference can reverse, forcing up-valley flows from the narrower towards the wider valley. In this regime, the volume-averaged cooling rate is found maximum and its magnitude dependent on the configuration considered. Therefore pooling and draining induce colder and deeper boundary layers than the respective valley-plain configurations. In the quasi-steady regime the cooling rate is smaller than in the transient regime, and almost independent of the configuration considered. Indeed, as the pooling character is more pronounced, the warming contribution from advection to the heat budget decreases because of weaker down-valley flows, and so does the cooling contribution from the surface sensible heat flux. The mass budget of the valley boundary layer was found to be controlled by a balance between the convergence of downslope flows at the boundary layer top and the divergence of down-valley flows along the valley axis, with negligible contributions of subsidence far from the slopes. The mass budget highlighted the importance of the return current above the down-valley flow, which may contribute significantly to the inflow of air at the top of the boundary layer. A case-study of a persistent cold-air pool event which occurred in February 2015 in the Arve River Valley during the intensive observation period 1 of the PASSY-2015 field campaign, allowed to quantify the effects of neighbouring valleys on the heat and mass budgets of a real valley atmosphere. The cold-air pool persisted because of warm air advection at the valley top, associated with the passage of an upper-level ridge over Europe. The contributions from each tributary valley to the mass and heat budgets of the valley atmosphere were found to vary from day to day within the persistent stage of the cold-air pool, depending on the large-scale flow. Tributary flows had significant impact on the height of the inversion layer and the strength of the cold-air pool, transporting a significant amount of mass within the valley atmosphere throughout the night. The strong stratification of the near-surface atmosphere prevented the tributary flows from penetrating down to the valley floor. The evolution of the large-scale flow during the episode had a profound impact on the near-surface circulation of the valley. The channelling of the large-scale flow at night, can lead to the decrease of the horizontal temperature difference driving the near-surface down-valley flow, favouring the stagnation of the air close to the ground.
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A diversidade beta de comunidades de macroinvertebrados é menor em córregos degradados? Uma avaliação experimentalLibório, Rogério Aparecido 04 March 2011 (has links)
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Previous issue date: 2011-03-04 / Universidade Federal de Minas Gerais / Aiming to answer the question: preserved streams can sustain higher beta diversity than degraded streams? We estimated beta diversity of preserved and degraded streams during the rainy season of 2009 in pool and riffle areas using as substrate bags of leaf litter of tree species Talauma ovata. We analyzed the similarity in taxonomic composition of different mesohabitats using different indices of similarity (Sørensen, Morisita-Horn and Horn) and their corresponding estimators of diversity. Our study showed higher values of beta diversity in streams degraded when estimated by the similarity indices of Sørensen and Morisita-Horn. On the other hand the Horn index indicated no differences between the streams. This greater differentiation in faunistic composition between the different streams in degraded mesohabitats seems to be related to degradation of the riparian zone which favored the largest effect of hydrological disturbance due to increased volume of water especially in areas of pool resulting in elimination of taxa and increase local the dominance of more tolerant taxa, affecting beta diversity. This study paves the way for new understandings of the effects of degradation of riparian zones in streams, because the comparison between habitats within a given stream may provide a basis to assess their state of degradation, making possible new approaches to biomonitoring. / Com o objetivo de responder a pergunta: Córregos preservados podem sustentar uma maior diversidade beta que córregos degradados? Estimamos a diversidade beta de córregos preservados e degradados durante a estação chuvosa de 2009 em áreas de remanso e corredeira utilizando como substrato sacos de detritos foliares da espécie arbórea Talauma ovata. Analisamos a similaridade na composição taxonômica dos diferentes mesohabitats utilizando diferentes índices de similaridade (Sørensen, Morisita-Horn e Horn) e seus estimadores de diversidade correspondentes. Nosso estudo mostrou maiores valores de diversidade beta nos córregos degradados quando estimado pelos índices de similaridade de Sørensen e Morisita-Horn. Já o índice de Horn não indicou diferenças entre os córregos. Esta maior diferenciação na composição faunística entre os diferentes mesohabitats nos córregos degradados parece estar relacionada à degradação da zona ripária que favoreceu o maior efeito das perturbações hidrológicas devido ao maior volume de água especialmente nas áreas de remanso, resultando em eliminação local de táxons e aumento na dominância de táxons mais tolerantes, afetando a diversidade beta. Este estudo abre caminho para novas perspectivas de compreensão dos efeitos da degradação das zonas ripárias em córregos, pois a comparação entre habitats dentro de um dado córrego pode fornecer subsídios para avaliar seu estado de degradação, possibilitando novas abordagens de biomonitoramento.
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Cycle des nutriments dans les mares d’une tourbière ombrotrophe du sud du QuébecArsenault, Julien 01 1900 (has links)
No description available.
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Biodiverzita a ekologie makrofyt vybraných stojatých vod v aluviu horního toku Lužnice / Biodiversity and ecology of makrophytes in selected standing waters in the floodplain of the Lužnice riverDVOŘÁKOVÁ, Olga January 2008 (has links)
This is a field study describing seven backwaters in the floodplain of the Luznice river. The backwaters include alluvial pools, river arms and oxbows which differ in their genesis, morfology, hydrological régime, macrophyte vegetation and chemistry of water and sediments. This study was carried out in the Trebonsko - Protected Landscape Area and Biosphere Reserve, South Bohemia, Czech Republic. The data of species composition of the vegetation on transects of the backwaters are supplemented by water and sedimet analyses.
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Importância da hidroconectividade e do banco de ovos de resistência na recolonização de ambientes costeiros por organismos zooplanctônicosAraújo, Luciana Rabelo de 27 February 2012 (has links)
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Previous issue date: 2012-02-27 / Poças adjacentes em ambientes aquáticos costeiros podem servir como refúgio para organismos em condições ambientais desfavoráveis, desde que haja conexão hidrológica entre os sistemas. Neste trabalho, foram avaliados os fatores estruturadores e a importância da hidroconectividade para comunidades zooplanctônicas de 3 lagoas salinas e 15 poças adjacentes localizadas em Quissamã/RJ, e o papel do banco de ovos de resistência na recolonização de uma lagoa costeira. Amostras da comunidade e das variáveis ambientais foram coletadas no período de um ano (Maio 2010 – Fevereiro 2011) e o banco de ovos foi coletado em agosto de 2010 no sistema Garça. Através de uma NMS utilizando o índice de similaridade de Bray-Curtis, as poças mostraram ser mais similares entre si do que com as lagoas, independente do período (seca ou chuva). Uma RDA mostrou que a salinidade e o pH foram os principais fatores estruturadores das comunidades. O cálculo da diversidade beta evidenciou que as poças apresentaram uma menor turnover temporal. No sistema Garça, as poças apresentaram bancos de ovos mais ricos que a lagoa, e 45% das espécies registradas na comunidade ativa da lagoa foram registradas exclusivamente nas poças. Embora as lagoas e suas poças não tenham sido mais similares no período chuvoso, a conectividade parece ter uma grande importância, devido à presença de espécies dulcícolas nas lagoas nos períodos mais chuvosos, encontradas também nas poças. Este fato, além da menor diversidade beta exibida pelas poças sugere que a dispersão não é limitante, possivelmente formando uma metacomunidade. A alta contribuição da comunidade ativa e dormente das poças para a comunidade ativa da lagoa da Garça mostra o potencial destes ambientes na manutenção e recolonização da comunidade zooplanctônica deste sistema. / Small-sized pools next to coastal lakes may serve as refuge for organisms during unfavorable environmental conditions in the lakes, due to sporadic connections between all aquatic systems. We assessed the importance of environmental variables and of the hydrological connectivity for the structure of zooplankton communities in three saline lagoons and 15 adjacent pools from Brazil. We also evaluated the role of the resting egg bank in the recolonization of the zooplankton community in one coastal lagoon. Zooplankton and environmental variables were collected during one year (2010–2011) and the resting egg bank was collected in August 2010 in the Garça system. NMS analyses using a Bray-Curtis index showed that the pools were more similar between each other than between the lagoons, regardless of the season (dry or rainy). A RDA showed that salinity and pH were the main structuring factors of communities in all lagoon systems. The beta-diversity index demonstrated that the lagoons had a higher temporal turnover. In the Garça system, the pools showed richer egg banks than the lagoon and 45% of the species recorded in the lake’s active community were founded in the pools. Although lagoons and pools were not more similar in the rainy season, the connectivity seems to have a major role due to the presence of freshwater species in the lakes, that were also found in the pools. This fact, plus the lower beta diversity showed by pools suggest that dispersal is not limited. The high contribution of the active and dormant communities of the pools for Garça lake’s active community shows the potential of these environments in the maintenance and recolonization of zooplankton community in this system.
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The dynamics of microalgal communities in response to environmental variables and nutrient fluxes in ephemeral wetlands in the Nelson Mandela Bay MetropoleLategan, Jodi January 2016 (has links)
Ephemeral wetlands provide numerous ecosystem services, but are disappearing due to urbanisation and habitat fragmentation. Knowledge is required to conserve these systems, but ephemeral wetland research in South Africa is lacking. As primary producers, microalgae provide a key link between the biotic and abiotic components of aquatic ecosystems. Despite their importance, there is a paucity in information concerning microalgal dynamics in ephemeral wetlands. The aim of this study was to understand the spatial and temporal dynamics of microalgae in ephemeral wetlands of the Nelson Mandela Bay Metropole. The research followed a funnel-based approach that assessed 35 wetlands at a regional level, followed by a temporal assessment of six wetlands, monitored biweekly, monthly or quarterly. Thereafter, a case study at local scale was carried out to address wetland connectivity and Hydrogeomorphic unit trends. The research culminated in a benthic flux chamber experiment, addressing the influence of microalgal-mediated processes on wetland development for a month post inundation. Phytoplankton biomass showed strong regional associations with rainfall zone, with Chl a concentrations of 17; 4.6; and 25 µg.L-1 in the high, intermediate and low rainfall zones, respectively. The MPB communities in Seeps, Depressions and Wetland flats, comprised between 45 and 60 % diatoms, whilst other microalgal groups were dominant in the water columns (> 90 %). Phytoplankton and MPB interactions facilitated significant night-time NH4+ and SRP effluxes, (1.5 and 0.4 mg.m-2.h-1, respectively) four days post inundation. High Silica uptake in the latter stages, was attributed to an increase in diatom abundance. Within the chambers, MPB growth was continuous whilst phytoplankton exhibited cyclical growth as the system approached dynamic equilibrium. This study demonstrated the importance of nutrient cycling in structuring aquatic food webs, and indicated the sensitivity of ephemeral wetlands to environmental perturbations.
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Dynamika uvolňování živin v průběhu procesu dekompozice smrkového dřeva v prostředí horského lesa / Mineralization of nutrients during the process of spruce dead wood decomposition in the mountain forestVišňová, Anna January 2017 (has links)
Summary: This thesis is focused on collecting information on the importance of dead wood on biogeochemical cycles of chemical elements in the mountain forest ecosystems of central Europe. The goal of this thesis was to determine the concentration of various elements(C, N, P, Ca, Mg, K, Na, Mn, Al, Fe) in the coarse woody debris of spruce samples of different age, stage of decomposition which were collected in different localities in the national park Šumava. Another goal was to determine the speed of which these elements are released from the dead wood. The information on the quantity of different elements and the speed of their release is currently lacking and could lead to better understanding of various biogeochemical cycles of elements in the mountain forest. During the decomposition the concentration of the elements N, P, Al and Fe increased whereas the Kalium concentration decreased. The other elements' (C, N, Ca, Mg, Mn) concentrations varied. Carbon constituted approximately 50% of weight in all of the samples analyzed. We carried out a laboratory experiment based on decomposition of dead wood samples in various stage of decay during a period of six months. The released concentration of CO2 was measured at two to four weeks intervals. The release of CO2 continually decreased during the experiment.....
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Centro de alto rendimiento para remo / High performance rowing centerHerrera Mendoza, Ana Claudia 29 September 2019 (has links)
El proyecto busca satisfacer las necesidades de un deportista de alto rendimiento de remo, para esto tiene zonas esenciales para su desarrollo y entrenamiento como un gimnasio con áreas para cardio (que incluye remoergometros) y musculación, una residencia, área de bienestar y rehabilitación, así como pozas de entrenamiento y el hangar de embarcaciones. Así mismo cuenta con una terraza para visitantes para eventos o días de competencia. La ubicación del proyecto es esencial porque al estar en un medio natural ayuda a la alta concentración del deportista y permite que el deporte se realice con eficacia, el lugar elegido es la “albufera de medio mundo” que es una laguna de 7km de largo, y que es propicia para la práctica del remo porque cuenta con aguas tranquilas las cuales son muy importantes para llevar a cabo del deporte, cabe resaltar el medio tranquilo, natural y aislado de la ciudad ayuda a la plena concentración. Ante este entorno natural y de conservación se ha optado por una construcción sostenible que respete y tenga compromiso con el medio ambiente, este implica el uso eficiente de la energía solar y el tratamiento del agua, la orientación del edificio para aprovechar los vientos y tener ventilación cruzada, así como un sistema constructivo de madera elevado sobre el nivel del suelo para reducir el impacto y que perdure ante la acción del medio costero. / The project seeks to satisfy the needs of a high performance rowing athlete, for this it has essential areas for its development and training as a gym with areas for cardio (which includes remoegometros) and fitness, a residence, wellness and rehabilitation area as well as rowing tanks and the boat storage. It also has a terrace for visitors for events or days of competition. The location of the project is essential because being in a natural environment helps the high concentration of the athlete and allows the sport to be carried out effectively, the chosen place is the "Albufera de Medio Mundo" which is a lagoon of 7km long, and that is conducive to the practice of rowing because it has calm waters which are very important to carry out the sport, it is worth highlighting the quiet, natural and isolated environment of the city helps the full concentration. Faced with this natural environment and conservation has opted for a sustainable construction that respects and is committed to the environment, this involves the efficient use of solar energy and water treatment, the orientation of the building to take advantage of the winds and have ventilation crossed as well as a constructive system of wood raised above ground level to reduce the impact and to last before the action of the coastal environment. / Tesis
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