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Raster based coastal marsh classification within the Galveston Bay ecosystem, TexasEdwards, Aron Shaun 15 May 2009 (has links)
A mapping study using remote sensing software called ENVI was conducted utilizing four
software algorithms to investigate whether these techniques could accurately classify habitat types and
vegetation communities along West Bay of the Galveston Bay Ecosystem from color infra-red (CIR)
imagery. The algorithms were used in a small-scale study to investigate which of these techniques could
most accurately distinguish habitat types and vegetation communities from the imagery at a site specific
location. The most accurate algorithm of the four was used in a large-scale classification study in which
entire images were classified utilizing the same data from the small-scale study.
Regions of interest (ROIs) were used within ENVI to specify areas of interest within each image
that was classified. The locations of ROIs were recorded using a GPS prior to classification, then each
was added into ENVI as data points, and each ROI polygon was digitized according to its respective pixel
color. Once all of the ROI polygons were completed, each software algorithm was employed.
After classification, each habitat type and vegetation community was ground-truthed in order to
verify the accuracy of the algorithms. The position points were added as ground truth points within ENVI
and an accuracy matrix was assessed. The technique with the greatest averaged accuracy within the smallscale
study was selected for the large-scale study. The ROIs and ground truth points used in the smallscale
study were used again in the large-scale study.
The small-scale study concluded that the Parallelepiped algorithm produced significantly less
accurate classifications than the other three. Although the Mahalanobis algorithm was not significantly
different from the other two algorithms, it yielded the highest overall average accuracy and was used in the
large-scale study. In both the small-scale and large-scale studies there was no significant difference in the
two different years of aerial imagery and there were no significant differences in accuracy for locations. None of the software algorithms were accurate at classifying habitat types and vegetation communities
using the imagery. The accuracy for the Mahalanobis algorithm was less than 60%. Inaccuracies were
largely due to overlapping spectral signatures among habitat types and vegetation communities.
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High-Fidelity Numerical Simulation of Shallow Water WavesZainali, Amir 09 December 2016 (has links)
Tsunamis impose significant threat to human life and coastal infrastructure. The goal of my dissertation is to develop a robust, accurate, and computationally efficient numerical model for quantitative hazard assessment of tsunamis. The length scale of the physical domain of interest ranges from hundreds of kilometers, in the case of landslide-generated tsunamis, to thousands of kilometers, in the case of far-field tsunamis, while the water depth varies from couple of kilometers, in deep ocean, to few centimeters, in the vicinity of shoreline. The large multi-scale computational domain leads to challenging and expensive numerical simulations. I present and compare the numerical results for different important problems --- such as tsunami hazard mitigation due to presence of coastal vegetation, boulder dislodgement and displacement by long waves, and tsunamis generated by an asteroid impact --- in risk assessment of tsunamis. I employ depth-integrated shallow water equations and Serre-Green-Naghdi equations for solving the problems and compare them to available three-dimensional results obtained by mesh-free smoothed particle hydrodynamics and volume of fluid methods. My results suggest that depth-integrated equations, given the current hardware computational capacities and the large scales of the problems in hand, can produce results as accurate as three-dimensional schemes while being computationally more efficient by at least an order of a magnitude. / Ph. D.
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Potential Wave Impacts On Shorelines In Intertidal WaterwaysRies, Collin 01 January 2016 (has links)
Coastal erosion is caused by a deficit in the sediment balance along coastal shorelines. Within the intertidal waterway of Jacksonville, Florida, the primary processes acting on the shoreline are tidal currents and waves generated by winds and passing vessels. This study focuses on the analysis of vessel-generated waves and their possible effects on different shoreline types. The experiment conducted herein examines variations in turbidity related to passing boats at a specifically selected site location, at which different tidal stages expose three different shoreline types, a non-vegetated scarp, a vegetated scarp and a vegetated area with no scarp in the breaking zone. Statistical analyses were used to quantify relationships between turbidity and wave height within these three different shoreline types. It was determined that both wave heights and the type of shoreline can affect local turbidity levels. Shorelines that contained vegetation experienced significantly less turbidity, than shorelines with no vegetation. Based on the findings here, some preventative measures are suggested to reduce the erosion of intracoastal shorelines into the channel. This would most likely entail boating restrictions or some protective measures to shelter the intracoastal banks.
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Risk assessment for Linear Alkylbenzene Sulfonates in Mediterranean coastal forest exposed to marine aerosols: a physiological perspectiveJalba, Adriana 09 February 2011 (has links)
The aim of this study was to understand the contribution of Linear Alkylbenzene Sulfonates (LAS) to the decline of Mediterranean coastal forest exposed to marine aerosols. LAS are a group of synthetic anionic surfactants widely used in the composition of household or industrial detergents and agrochemicals. This study was part of a large project (RISICO) aiming the assessment of the environmental impact of the LAS at multiple levels: biodegradation in the coastal waters, sorption – desorption processes in the sediments, toxicity to the aquatic life and toxicity to the coastal forest (by aerosolisation of the sea water).
Previous studies pointed out this group of surfactants as the main cause of the coastal forest decline. However, the quantification of this surfactant in the environmental samples (mainly sea water and foliar deposition) was done using non-specific analytical methods as methylene blue active substances (MBAS), leading to overestimation of the environmental concentrations of LAS.
The work hypothesis was that at actual environmental concentrations, the LAS does not play a key role in the foliar uptake of the sea salt deposited on the coastal vegetation by the marine aerosols, therefore the LAS may not be the main cause of the coastal forest decline.
The research involved both greenhouse experiments and field measurements. The experimental work was conducted on young Mediterranean trees (Laurus nobilis L., Quercus ilex L. and Pinus halepensis P. Mill.) and investigated the synergistic toxic effects of exposure to simulated marine aerosol contaminated with surfactants. An array of endpoints was used including photosynthetic activity, relative water content, foliar deposition and uptake of salt and LAS, and pigments analysis. The results of those experiments revealed that LAS itself did not have phytotoxic effects. Nevertheless, the surfactant was shown to enhance the foliar uptake of the salt in the tested species, especially in Pinus halepensis, confirming the conclusions of previous studies regarding the sensitivity of this species to polluted marine aerosols.
The field work was conducted in San Rossore National Park (Italy) and Porquerolles Island (France) and was focused on evaluating the health status of the Mediterranean forest (Quercus ilex L., Pinus halepensis Mill. and Pinus pinaster Aiton.) and also on quantification of LAS in coastal aerosols using highly specific analytical methods, like the mass spectrometry (MS). The frequencies and extent of injuries in the coastal trees were found to be correlated to the salt but not with the LAS content of the leaves. The concentrations of LAS in the Pinus and Quercus leaves were comparable in the two studied sites but the concentrations of salt were extremely high in San Rossore, suggesting that other factors may determine the excessive salt foliar uptake. The parallel MS and MBAS carried out in the same set of aerosol samples revealed that MBAS measurements were not relevant for LAS concentrations in the marine aerosols. Projecting the experimental results to the real LAS and salt exposure of the coastal forest, we concluded that LAS may play a marginal role in coastal vegetation decline.
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Root system structure and functions across coastal saltmarsh flooding gradientsRedelstein, Regine 08 February 2018 (has links)
No description available.
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Hodnocení vegetace pobřeží zatopených pískoven s využitím obrazové analýzy fotografického materiálu / Evaluation of vegetation flooded coast sand using image analysis of photographic materialHEYDUKOVÁ, Kateřina January 2012 (has links)
The main aim of this study was added and verified metodology, analysis of quality and quantity coastal vegetation, considering experience about my previous bachelor´s work and with help pictorial analysis. The ekotonal vegetation were analysed at 9 km long section of coastline, included three sandy-gravel lake (Cep II., Tušť a Františkov). Pictorial analysis, photographs about coastline, was refilled in fytocenology snapshots. Pursuase of this study were discussed influences of cause succession coastal vegetation, species variety and utility of method analysis of pictorial to evaluace vegetation.
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Qualidade e potencial antioxidante de frutas nativas do litoral cearense em diferentes estÃdios de maturaÃÃo. / QUALITY AND ANTIOXIDANT POTENTIAL OF FRUITS COASTAL NATIVE CEARENSE AT DIFFERENT STAGES OF RIPENINGRafaela Vieira FaÃanha 28 February 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / O presente trabalho teve como objetivo avaliar as caracterÃsticas fÃsicas, fÃsico-quÃmicas e quÃmicas e atividade antioxidante total de frutos de viuvinha (Myrcia splendens (Sw.) DC.), mapirunga (Eugenia tinctoria Gagnep.) e araticum-do-brejo (Annona glabra L.) oriundos da vegetaÃÃo litorÃnea do CearÃ, em diferentes estÃdios de maturaÃÃo. Os frutos foram caracterizados fisicamente quanto à massa fresca, dimensÃes, coloraÃÃo, rendimento e firmeza. Para a avaliaÃÃo das caracterÃsticas fÃsico-quÃmicas e quÃmicas foram feitas as seguintes anÃlises: sÃlidos solÃveis (SS), acidez total titulÃvel (ATT), pH, relaÃÃo SS/ATT, aÃÃcares solÃveis totais e redutores, pectina solÃvel, vitamina C, clorofila e carotenÃides totais, antocianinas e flavonÃides amarelos, polifenÃis extraÃveis totais (PET) e atividade antioxidante total pelo mÃtodo ABTS. Os resultados indicaram que os frutos de viuvinha e mapirunga apresentaram um aumento na massa fresca, comprimento, diÃmetro e rendimento em polpa no decorrer do amadurecimento. Nos frutos de araticum-do-brejo observou-se um declÃnio nestes parÃmetros no final da maturaÃÃo. Observou-se tambÃm um aumento, no teor de sÃlidos solÃveis totais, na relaÃÃo SS/ATT, aÃÃcares solÃveis totais e aÃÃcares redutores nos frutos analisados à medida em que ocorria a hidrÃlise do amido. Apenas nos frutos de viuvinha ocorreu diminuiÃÃo da acidez ao longo do amadurecimento. Houve solubilizaÃÃo da pectina ao longo do amadurecimento, exceto nos frutos de mapirunga. Dentre os compostos bioativos observou-se aumento na vitamina C no decorrer do amadurecimento das frutas analisadas. Constatou-se alto teor de antocianinas nos Ãltimos estÃdios de maturaÃÃo na polpa de mapirunga. Apenas nos frutos de viuvinha houve uma diminuiÃÃo de flavonÃides amarelos no decorrer do amadurecimento. Foram encontrados altos valores de polifÃnois extraÃveis totais e elevada atividade antioxidante nos frutos de viuvinha e mapirunga. Houve correlaÃÃo positiva e significativa entre a atividade antioxidante total e o teor de polifenÃis extraÃveis totais de todas as espÃcies analisadas. As polpas de viuvinha e mapirunga sÃo promissoras tendo em vista considerÃveis teores de compostos bioativos como, carotenÃides, antocianinas, flavonÃides amarelos e polifenÃis totais extraÃveis que as fazem produtos diferenciais no mercado de frutas nativas. / O presente trabalho teve como objetivo avaliar as caracterÃsticas fÃsicas, fÃsico-quÃmicas e quÃmicas e atividade antioxidante total de frutos de viuvinha (Myrcia splendens (Sw.) DC.), mapirunga (Eugenia tinctoria Gagnep.) e araticum-do-brejo (Annona glabra L.) oriundos da vegetaÃÃo litorÃnea do CearÃ, em diferentes estÃdios de maturaÃÃo. Os frutos foram caracterizados fisicamente quanto à massa fresca, dimensÃes, coloraÃÃo, rendimento e firmeza. Para a avaliaÃÃo das caracterÃsticas fÃsico-quÃmicas e quÃmicas foram feitas as seguintes anÃlises: sÃlidos solÃveis (SS), acidez total titulÃvel (ATT), pH, relaÃÃo SS/ATT, aÃÃcares solÃveis totais e redutores, pectina solÃvel, vitamina C, clorofila e carotenÃides totais, antocianinas e flavonÃides amarelos, polifenÃis extraÃveis totais (PET) e atividade antioxidante total pelo mÃtodo ABTS. Os resultados indicaram que os frutos de viuvinha e mapirunga apresentaram um aumento na massa fresca, comprimento, diÃmetro e rendimento em polpa no decorrer do amadurecimento. Nos frutos de araticum-do-brejo observou-se um declÃnio nestes parÃmetros no final da maturaÃÃo. Observou-se tambÃm um aumento, no teor de sÃlidos solÃveis totais, na relaÃÃo SS/ATT, aÃÃcares solÃveis totais e aÃÃcares redutores nos frutos analisados à medida em que ocorria a hidrÃlise do amido. Apenas nos frutos de viuvinha ocorreu diminuiÃÃo da acidez ao longo do amadurecimento. Houve solubilizaÃÃo da pectina ao longo do amadurecimento, exceto nos frutos de mapirunga. Dentre os compostos bioativos observou-se aumento na vitamina C no decorrer do amadurecimento das frutas analisadas. Constatou-se alto teor de antocianinas nos Ãltimos estÃdios de maturaÃÃo na polpa de mapirunga. Apenas nos frutos de viuvinha houve uma diminuiÃÃo de flavonÃides amarelos no decorrer do amadurecimento. Foram encontrados altos valores de polifÃnois extraÃveis totais e elevada atividade antioxidante nos frutos de viuvinha e mapirunga. Houve correlaÃÃo positiva e significativa entre a atividade antioxidante total e o teor de polifenÃis extraÃveis totais de todas as espÃcies analisadas. As polpas de viuvinha e mapirunga sÃo promissoras tendo em vista considerÃveis teores de compostos bioativos como, carotenÃides, antocianinas, flavonÃides amarelos e polifenÃis totais extraÃveis que as fazem produtos diferenciais no mercado de frutas nativas. / The objective of this work was to characterize physical, chemical and physico-chemical and evaluate the total antioxidant activity of fruits of viuvinha (Myrcia splendens (Sw.) DC.), mapirunga (Eugenia tinctoria Gagnep.) and araticum-do-brejo (Annona glabra L.) from the coastal vegetation of CearÃ, at different stages of maturation. Fruits were physically characterized by size, color, total weight, yield, and firmness. For the evaluation of the physico-chemical and chemical analyzes were made as follows: soluble solids (SS), acidity, pH, SS / TA ratio, total soluble sugars and reducing sugars, soluble pectin, vitamin C, chlorophyll and total carotenois, anthocyanins and yellow flavonoids , total extractable polyphenols (TEP) and total antioxidant activity (TAA) by ABTS method. The study found that the fruits of viuvinha and mapirunga showed an increase in total weight, length, diameter and yield of the pulp during ripening. In fruits of araticum observed a decrease in these parameters at the end of maturation. Were also observed an increase in soluble solids, SS / TA ratio, total soluble sugars, reducing sugars in the fruits analyzed as starch hydrolysis occurred. Only the fruits of viuvinha there was a decrease in acidity during the ripening. There solubilization of pectin during ripening, except in the fruits of mapirunga. Among the bioactive compounds reported an increase in vitamin C during ripening of fruits analyzed. There was a high content of anthocyanins in late-stage of viuvinha and mapirunga. Only in the fruits of viuvinha there were yellow flavonoids during ripening. Emphasis was placed high values of extractable polyphenols and total antioxidant activity in fruits of viuvinha and mapirunga. There was significant positive correlation between total antioxidant activity and total extractable polyphenol content of all species analyzed. The pulp of viuvinha and mapirunga are promising in view of considerable amounts of bioactive compounds such as carotenoids, anthocyanins, yellow flavonoids and total polyphenols total extractable differentials that make products on the market of native fruits. / The objective of this work was to characterize physical, chemical and physico-chemical and evaluate the total antioxidant activity of fruits of viuvinha (Myrcia splendens (Sw.) DC.), mapirunga (Eugenia tinctoria Gagnep.) and araticum-do-brejo (Annona glabra L.) from the coastal vegetation of CearÃ, at different stages of maturation. Fruits were physically characterized by size, color, total weight, yield, and firmness. For the evaluation of the physico-chemical and chemical analyzes were made as follows: soluble solids (SS), acidity, pH, SS / TA ratio, total soluble sugars and reducing sugars, soluble pectin, vitamin C, chlorophyll and total carotenois, anthocyanins and yellow flavonoids , total extractable polyphenols (TEP) and total antioxidant activity (TAA) by ABTS method. The study found that the fruits of viuvinha and mapirunga showed an increase in total weight, length, diameter and yield of the pulp during ripening. In fruits of araticum observed a decrease in these parameters at the end of maturation. Were also observed an increase in soluble solids, SS / TA ratio, total soluble sugars, reducing sugars in the fruits analyzed as starch hydrolysis occurred. Only the fruits of viuvinha there was a decrease in acidity during the ripening. There solubilization of pectin during ripening, except in the fruits of mapirunga. Among the bioactive compounds reported an increase in vitamin C during ripening of fruits analyzed. There was a high content of anthocyanins in late-stage of viuvinha and mapirunga. Only in the fruits of viuvinha there were yellow flavonoids during ripening. Emphasis was placed high values of extractable polyphenols and total antioxidant activity in fruits of viuvinha and mapirunga. There was significant positive correlation between total antioxidant activity and total extractable polyphenol content of all species analyzed. The pulp of viuvinha and mapirunga are promising in view of considerable amounts of bioactive compounds such as carotenoids, anthocyanins, yellow flavonoids and total polyphenols total extractable differentials that make products on the market of native fruits.
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Vegetation and functional diversity of sand dune habitats between and within different bioclimatic regionsMahdavi, Parastoo 26 April 2017 (has links)
No description available.
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Short-term Effects of Nutrients on a Barrier Island Grassland CommunityMoulton, Ashley 01 January 2017 (has links)
Increased nutrient availability globally has the potential to affect community functional composition of plants in nutrient limited environments, such as coastal grassland systems. Stability of these systems are threatened worldwide by urbanization, as well as effects of sea level rise and increased frequency and intensity of storms, and atmospheric N deposition, associated with climate change. Annual net primary productivity (ANPP), species composition, and functional traits (community weighted specific leaf area (CWSLA), leaf area index (LAI), growth form and photosynthetic pathway) were measured across four treatments to assess multiple resource limitation of nitrogen (N) and phosphorus (P) and functional community response in a coastal grassland on Hog Island, VA within the Virginia Coast Reserve, Long Term Ecological Research Network (LTER) applied at a rate of 10 g m-2 yr-1 Nutrient enrichment did not alter species diversity or richness. ANPP was highest in plots receiving any type of nitrogen enrichment, and was higher than expected of low nutrient systems. CWSLA was significantly higher in NP plots, and was lower than other grasslands. P treatments were not significantly different from controls. Graminoid species, specifically C4 species responded with higher ANPP than C3 forbs or graminoids within treatments. Evidence of synergistic NP effects were seen on community level resource allocation and leaf construction, but no significant species changes occurred over a 1-year time span. These results have expanded the knowledge of functional response to increased nutrient availability in an understudied, coastal grassland, which are at high risk to being lost to sea level rise and anthropogenic development and inform community assembly processes in stressful environments.
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The Distribution of Coral, Reefs and Coastal Habitats in North Central CubaBrady, Aisling 24 February 2009 (has links)
Coral communities have begun to form under small inlet-style bridges along the causeway connecting Cayo Coco to Cayo Guillermo. To understand how these bridge-reefs formed and characterize their attributes relative to surrounding communities, a combination of ecological observations and 13C isotopes were analyzed from the bridges and surrounding reefs, mangrove channels and seagrass patches. Hierarchical Cluster Analysis, Detrended Correspondence Analysis and Canonical Correspondence Analysis were carried out to group which physical attributes contributed to the coral communities in the bridge-reefs and also which habitats they were most similar to, with respect to coral and benthic composition. Bridge reef coral assemblages resembled shallow patch reefs and mangrove channels, while benthic coverage was similar to mangrove channels. Organic matter was from combined seagrass and mangrove sources, with mangrove dominating in some regions more than others. This work demonstrates that habitats within the seascape are inter-related through varying mechanisms and development is multi-dimensional.
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