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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.
61

Simulações computacionais na proteína TM1030 da bactéria hipertermófila Thermotoga maritima / Computational simulations at TM1030 protein of hyperthermofile Thermotoga maritima bacterium

David Leandro Palomino Salcedo 19 January 2016 (has links)
A Thermotoga marítima (Tm) é uma bactéria que vive em temperaturas na faixa dos 65 até 90°C, com temperatura ótima do redor dos 80°C. A proteína TM1030 de Tm, é um regulador transcricional da família TetR (Tetracycline repressor protein) reguladores da expressão génica das proteínas TetA e TetB (Tetracycline resistance protein). Neste trabalho se rodarem 200ns de trajetória de dinâmica molecular a três temperaturas (293, 323 e 353K) da proteína TM1030 (PDB-1Z77) usando o pacote GROMACS com o potencial Amber99 e solvente explicito numa caixa cúbica com 90Å de comprimento, observando que RMSD da estrutura média da trajetória é menor em relação à estrutura cristalográfica, além disso que num primer momento esse RMSD tem uma mudança grande e que se estabiliza com uma maior velocidade nas maiores temperaturas. Também foi feito um analise de modos normais na mesma estrutura usando o mesmo potencial, mas com solvente implícito, usando o modelo GBSA, minimizando a estrutura até ter um coeficiente de força média de 6,4x10-8J·mol-1·cm-1 que assegura um bom mínimo local. Das trajetórias simuladas a partir das 6 menores frequências se achou uma relação com os movimentos observados nas dinâmicas moleculares e os esperados na transição alostérica entre as duas estruturas cristalográficas. Finalmente se calculam os fatores de temperatura das três trajetórias de dinâmica molecular, observando que seus esses fatores de temperatura aumentam com o aumento da temperatura, contrario do esperado da cristalografia onde diminuam com o aumento da temperatura do sistema. / The Thermotoga maritima (Tm) is a bacterium who can lives at temperatures of 65 to 90°C, with optimum temperature around of 80°C. The TM1030 protein of Tm is a transcriptional regulator from TetR family (Tetracycline repressor protein) regulators of gene expression of the TetA and TetB protein (Tetracycline resistance protein). In this work 200ns of molecular dynamics trajectory was run at three temperatures (293, 323 and 353K) of TM1030 protein (PDB-1Z77) using GROMACS package with Amber99 potential and explicit solvent in a cubic box with length 90A, noting that RMSD of the average structure of the trajectory is smaller with respect to the crystallographic structure, in addition, in a first time this RMSD have a large change and stabilizes at a higher speed at higher temperatures. There was also an analysis of normal modes on the same structure using the same potential, but with implicit solvent, using the GBSA model, minimizing the structure to have a medium force coefficient of 6,4x10-8J·mol-1·cm-1which ensures a good local minimum. Of the trajectories simulated from 6 lower frequencies was found a relationship with the movements observed in molecular dynamics and expected the allosteric transition between the two crystal structures. Finally was calculate the temperature factor of the three trajectories of molecular dynamics, observing their temperature factors increase with increasing temperature, contrary to expectations of crystallography which decrease with the increase of the system temperature.
62

Aspects of the ecology and biology of the isopod, Exosphaeroma hylocoetes, (Barnard, 1940) in three temporarily open/closed southern African estuaries

Henninger, Tony Oskar January 2009 (has links)
Temporarily open/closed estuaries (TOCE’s) are the numerically dominant type of estuary accounting for ≈ 70 % of all estuaries along the South African coastline. Despite their numerical dominance, aspects of the biology of organisms within these systems, particularly macrocrustacea remain poorly understood. This study firstly assessed the abundance and biomass of the most common isopod, Exosphaeroma hylocoetes, in three Eastern Cape TOCE’s, (the West Kleinemonde, East Kleinemonde and Kasouga Estuaries), and their response to mouth breaching events. This study was followed by aspects of the biology of the isopod including their utilisation of submerged macrophytes as a refuge from predation and/or possible food source, as well as the growth rates of the isopods in the laboratory under different environmental conditions. Mean isopod abundances and biomasses ranged between 0 and 4 791 ind. m⁻² and 0 and 9.65 mg dwt. m⁻² in the West Kleinemonde Estuary and between 0 and 108 ind. m⁻² and 0 and 0.318 mg dwt. m⁻² in the nearby East Kleinemonde Estuary. In the Kasouga Estuary, the values ranged between 0 and 3 650 ind. m⁻² and 0 and 5.105 mg dwt. m⁻². Temporal and spatial changes in the abundance and biomass of E. hylocoetes within the three systems was primarily linked to mouth phase, with populations declining when the mouth was open and to a lesser extent, seasonality. In all three estuaries maximum isopod abundances and biomasses were recorded in their middle and upper reaches, which could be ascribed to the presence of submerged macrophytes particularly Ruppia maritima, in two of the estuaries. Males (5.71 ± 0.41 mm) were significantly larger than females (3.99 ± 0.26 mm), but the sex ratios were skewed in favour of females, (a common feature in many isopod populations). Females were found carrying brood throughout the study, releasing offspring directly into the water column, to allow recruitment to the populations. The larger the female, the larger the brood carried (up to a maximum of 72 embryo/mancas). Results of laboratory experiments indicate that the close association of Exosphaeroma hylocoetes with submerged macrophytes is a result of the plant stands providing a refuge against predation by selected ichthyofauna. However stable carbon isotope and fatty acid analyses indicate that E. hylocoetes made use of ephiphytic algae and detritus on the stems of R. maritima, rather than the submerged macrophyte itself. There were no significant differences in the growth rates of male and female isopods at combinations of temperature (15 and 25 °C) and salinity (15 and 35 ‰). Laboratory growth studies revealed that males lived longer than females (25.77 ± 3.40 weeks vs 21.52 ± 3.00 weeks), and therefore achieved larger overall size. Females, however, reached sexual maturity (at 2.5 mm) at a faster rate (two to four weeks) than males (5.5 mm after 6.5 to 11 weeks), dependent on temperature. Exosphaeroma hylocoetes with its association with submerged macrophytes, early maturity, its growth rates and longevity, female-biased sex ratios and year-round breeding, all contribute to its success in temporary open/closed estuaries.
63

Avaliação da atividade biológica do extrato seco da Remiria maritima Aubl. / ASSESSMENT OF BIOLOGICAL ACTIVITY OF EXTRACT DRY LYOPHILIZED REMIRIA MARITIMA AUBL.

Oliveira, Isamar Dantas 22 June 2010 (has links)
Remiria maritime Aubl., popularly known as "capim da praia" is used as teas to treat diarrhea, kidney disease, high fever and analgesic and antiinflammatory. There are no records in the literature about its biological properties. Therefore, this study was designed to evaluate the possible action of the antimicrobial effects, antioxidant, antinociceptive and antiinflammatory effect of aqueous extract of dried sea Remiria Aubl. (ERMA) using tests in vivo and in vitro. The extract was first subjected to tests phytochemicals. Antimicrobial activity was evaluated in vitro by the technique of disk diffusion method and minimum inhibitory concentration. The antioxidant effect was observed in vitro by testing the extent of lipid peroxidation (TBARS), nitric oxide (NO) and hydroxyl radical scavenger capacity where ERMA concentrations used were 10 μg/mL, 100 μg/mL e 1 mg/mL. The antinociceptive activity was evaluated by testing the writhing induced by acetic acid 0.9% and 1% formalin. The test of motor coordination was used to assess possible effects of muscle relaxants and sedatives ERMA might interfere with the antinociceptive effects. The anti-inflammatory activity was evaluated by testing peritonitis induced by carrageenan 1%. The animals (n = 6/group) were treated 30 min before each experiment, vehicle (saline + 0.2% Tween 80, ip) or ERMA (100, 200 and 400 mg / kg, ip). The phytochemical screening showed the presence of several chemical classes: phenols, tannins, alkaloids, volatile coumarins, flavonoids, saponins and triterpenes. The ERMA demonstrated antimicrobial activity against Gram-positive and negative. Additionally, evaluation of antioxidant activity in the TBARS assay, there was a reduction of lipid peroxidation (p <0.001). In the test of NO reduction occurred in the formation of nitric oxide (p <0.001). In the test to assess the ability of hydroxyl radical scavenger was significant with (p <0.001). Treatment with ERMA intraperitoneally produced a significant decrease in the number of writhing 100 (26.0 ± 2.1, p <0.01), 200 (25.1 ± 2.4, p <0.01) and 400 mg / kg (19.3 ± 2.9, p <0.001). In the formalin test, there was a reduced response Algic significantly only in the second phase, 200 mg / kg (22.9 ± 2.9, p <0.05) and 400 mg / kg (15.3 ± 3, 9, p <0.001). In the hot plate there was no significant difference in nociceptive behavior. In Rota rod test was verified that the ERMA does not alter the motor coordination of animals. In the test of peritonitis, treatment with ERMA promoted a significant reduction in leukocyte migration induced by carrageenan at all doses 100 (8.9 ± 0.1, p <0.01), 200 (6.6 ± 0.2 p <0.01) and 400 mg / kg (3.9 ± 0.6, p <0.01) . The results suggest that ERMA has antimicrobial activity, antioxidant, antinociceptive and antiinflammatory. However, further studies are required to better assess and characterize the mechanisms involved in these effects. / Remiria marítima Aubl., popularmente conhecida como Capim da praia é utilizada na forma de chás para o tratamento de diarréia, doenças renais, febre alta e como analgésico e antiinflamatório. Não há na literatura registros a respeito de suas propriedades biológicas. Portanto, este estudo foi desenvolvido visando avaliar a ação dos possíveis efeitos antimicrobiano, antioxidante, antinociceptivo e anti-inflamatório do extrato aquoso liofilizado da Remiria marítima Aubl. (ERMA) utilizando ensaios in vivo e in vitro. O extrato foi submetido primeiramente aos ensaios fitoquímicos. A atividade antimicrobiana foi avaliada in vitro pela técnica do método de disco difusão e concentração inibitória mínima. O efeito antioxidante foi verificado in vitro através do teste de medida da lipoperoxidação (TBARS), óxido nítrico (NO) e capacidade scavenger de radical hidroxila onde as concentrações do ERMA utilizadas foram 10 μg/mL, 100 μg/mL e 1 mg/mL. A atividade antinociceptiva foi avaliada através do teste das contorções abdominais induzidas pelo ácido acético a 0,9% e da formalina 1%. O teste da placa quente foi realizado para avaliar possivel ação central do ERMA. O teste da coordenação motora foi utilizado para avaliar possíveis efeitos miorrelaxantes e sedativos do ERMA que pudessem interferir nos efeitos antinociceptivos. A atividade anti-inflamatória foi avaliada através do teste da peritonite induzida por carragenina a 1%. Os animais (n = 6/grupo) foram tratados 30 min antes de cada experimento, com o veículo (salina + tween 80 0,2%; i.p.) ou ERMA (100, 200 e 400 mg/kg; i.p.). A triagem fitoquímica mostrou a presença de diversas classes quimicas: fenóis, taninos condensados, alcalóides, cumarinas voláteis, flavonóides, saponinas e triterpenos. O ERMA demonstrou ação antimicrobiana frente as bactérias Gram-positivas e negativas. Adicionalmente, na avaliação da atividade antioxidante, no teste TBARS, houve uma redução da lipoperoxidação (p < 0,001). No teste do NO, houve redução na formação de óxido nítrico (p < 0,001). No teste para avaliar a capacidade scavenger de radical hidroxila foi significativo com (p < 0,001). O tratamento com ERMA via intraperitonial produziu uma redução significativa do número de contorções abdominais 100 (26,0 ± 2,1; p < 0,01), 200 (25,1 ± 2,4; p < 0,01) e 400 mg/kg (19,3 ± 2,9; p < 0,001). No teste da formalina, houve uma redução da resposta álgica de maneira significativa apenas na segunda fase, 200 mg/kg (22,9 ± 2,9; p < 0,05) e 400 mg/kg (15,3 ± 3,9; p < 0,001). No teste da placa quente não houve diferença significativa no comportamento nociceptivo. No teste do Rota rod foi verificado que o ERMA não altera a coordenação motora dos animais. No teste da peritonite, o tratamento com ERMA promoveu uma redução significativa na migração dos leucócitos induzida pela carragenina em todas as doses 100 (8,9 ± 0,1; p < 0,01), 200 (6,6 ± 0,2; p < 0,01) e 400 mg/kg (3,9 ± 0,6; p < 0,01).. Os resultados sugerem que o ERMA possui efeito antimicrobiano, antioxidante, antinociceptivo e anti-inflamatório. Entretanto, novos estudos são requeridos para uma melhor avaliação e caracterização dos mecanismos envolvidos nesses efeitos.
64

Svensk maritim strategi – i takt med tiden?

Thern, Jonas January 2021 (has links)
Samverkan inom svenskt totalförsvar avseende operativa maritima resurser för säkerhetsfrämjande verksamhet till sjöss har under lång tid varit begränsad. Flera statliga utredningar, kommissioner och propositioner har konstaterat detta och trots att problemet är välkänt har initiativ till utökad samverkan mellan berörda myndigheter uteblivit. Den diversifierade och allt mer komplexa hotbild som uppstått sedan inledningen av 1980-talet, borde ha föranlett ett effektivt utnyttjande av de befintliga maritima resurserna, något som inte har skett. Denna studie undersöker hur Sveriges olika hotbilder under 1980-talet och 2020-talets har påverkat dess maritima strategi och nyttjande av sina nationella maritima resurser. I studien nyttjas Ken Booths klassiska teori för att beskriva en flottas funktioner, vilken modifieras och appliceras på de maritima komponenterna i det svenska totalförsvaret i syfte att beskriva förändring och kontinuitet. Studiens resultat visar att avsaknaden av en svensk holistisk maritim strategi försvårar samverkan och samordning mellan de maritima myndigheter som ingår i totalförsvaret och att Sveriges sektoriella syn på maritim säkerhet inte bidrar till att möta dagens gråzonsproblematik.
65

Operationalizing the SDGs in a Systems Engineering Framework for ship design concept studies / Operationalisering av de globala målen för hållbar utveckling i ett systemtekniskt ramverk för konceptstudier inom fartygsdesign

Ekman, Fanny January 2019 (has links)
Sustainable transport involves more choices and possibilities than ever before, and the topic is widely discussed within the maritime industry. To a large extent the innovations and technology exists, but even though there is a drive and consciousness to change, sustainability is still not a cornerstone in the decision-making process when new ships and transport solutions are developed. The gap between sustainability ambitions and actual actions is far from closed. This thesis introduces a new framework called Systems Engineering for Sustainable Ship design (SE4SS), which is based on the Systems Engineering methodology for conducting concept developments and the Sustainable Development Goals (SDG) for operationalizing sustainability. The new framework makes sustainability aspects an essential part of ship design concept development and the following decision-making process. The SE4SS framework includes an application of the SDGs on a product level (ship) and suggests appropriate tools &amp; methods for sustainability assessment, considering different levels of ambitions and amount of available resources that projects may have. The framework has been validated against three cases of ship design concept development within the commissioner organization SSPA. The result shows that the suggested approach is useful in terms of ; (1) raising a holistic awareness of sustainability aspects in ship design, highlighting the existing opportunities and responsibilities, (2) creating a more transparent trade-off analysis where priorities need to be stated, preventing greenwashing, (3) structuring the process which facilitates the integration of sustainability aspects from the start and the communication between the project manager/naval architect and different stakeholders. Full-scale application of the SE4SS is needed in order to fully validate its usability and generalizability, however this thesis argues that the introduced framework may be a valuable tool in both illuminating and reducing the ambition-action gap within the maritime sector. / Hållbara transporter involverar fler val och möjligheter än någonsin tidigare och ämnet är mycket omdiskuterat inom den maritima industrin. Till stor del så finns redan innovationerna och teknologin som krävs för en hållbar omställning, men trots ett driv och en medvetenhet kring förändring så är hållbarhet fortfarande inte en grundsten i beslutsfattandeprocessennär nya fartyg och transportlösningar utvecklas. Gapet mellan hållbarhetsambitioner och faktiska handlingar är fortfarande stort.Den här masteruppsatsen introducerar ett nytt ramverk kallat systemteknik för hållbar skeppsdesign (SE4SS) som baseras på en systemteknisk metodik för konceptutveckling där FNs globala mål (SDGna) för hållbar utveckling har använts för att operationalisera hållbarhet. Detta nya ramverk gör hållbarhets aspekter till en grundläggande del i konceptutvecklingen av fartyg och den efter följande beslutsprocessen.SE4SS-ramverket inkluderar en applicering av SDGna på produktnivå (fartyg) och föreslår lämpliga verktyg &amp; metoder för hållbarhetsanalyser, där hänsyn tas till att olika ambitionsnivåer samt tillgängliga resurser projekt kan ha.Ramverket har validerats gentemot tre fallstudier av konceptstudier inom fartygsdesign som genomförts av det uppdragsbeställande företaget SSPA. Resultatet visar att det föreslagna ramverket är användbart med avseende på; (1) skapar en holistisk medvetenhet när det gäller hållbarhetsaspekter inom fartygsprojektering där möjligheter och ansvar betonas,(2) skapar en mer transparent avvägningsanalys där prioriteringar måste fastställas, vilket försvårar grönmålning, (3) strukturerar utvecklingsprocessen vilket underlättar både integreringen av hållbarhetsfrågor från början och kommunikationen mellan projektledaren/skeppsdesignern och olika intressenter. Fullskalig applicering av SE4SS behövs för att stärka valideringen kring användarbarhet och generaliserbarhet, emellertid så argumenterar denna uppsats för att det introducerade ramverket kan vara ett värdefullt verktyg när det gäller att både belysa och minska ambition-handlingsgapet inom den maritima branschen.
66

Vergleichende biochemische und strukturelle Untersuchung thermophiler α-Amylasen / Comparative biochemical and structural studies of thermophilic α-amylases

Ballschmiter, Meike 27 April 2005 (has links)
No description available.
67

Versuche zur Strukturaufklärung bakterieller Thiouridin Synthetasen / Crystallization and structure determination attempts with bacterial thiouridine synthetases

Naumann, Peter-Thomas 18 January 2006 (has links)
No description available.
68

Etude de deux halophytes, Armeria maritima (Mill.) Willd. et Helichrysum stoechas (L.) Moench : exploration phytochimique, approche biotechnologique et valorisation dermo-cosmétique / Study of two halophytes, Armeria maritima (Mill.) Willd. et Helichrysum stoechas (L.) Moench : phytochemical exploration, biotechnological approach and dermocosmetic valorization.

Gourguillon, Lorène 03 July 2017 (has links)
L'étude phytochimique d'Armeria maritima et d'Helichrysum stoechas a permis d'isoler pour la première fois 31 molécules dans le genre Armeria dont 4 nouveaux flavonols diglycosylés, ainsi que le développement d'une stratégie de déréplication pour l'étude d'H. stoechas. Dans les deux espèces, nous avons relevé une richesse en polyphénols, qui pourraient être extraits par des techniques respectueuses de l'environnement comme la SFE. En parallèle, ces deux halophytes ont montré un fort potentiel biologique avec des extraits et des molécules dotés d'activités anti-oxydante, anti-collagénase, anti-inflammatoire ou encore cicatrisante. De plus, nous avons initié pour la première fois des suspensions cellulaires d'A. maritima et identifié des éliciteurs comme le méthyl jasmonate permettant d’augmenter dans les cellules d'H. stoechas la teneur en acide 3,5-dicaféoylquinique, un bio-marqueur de l'activité anti-inflammatoire. La production de molécules bioactives dans des cultures végétales in vitro pourrait par la suite être transposée à plus grande échelle, afin d’amplifier le potentiel de valorisation de ces deux halophytes en dermo-cosmétique. / The phytochemical study of Armeria maritima and Helichrysum stoechas led to the isolation of 31 molecules never reported before in the genus Armeria, 4 of which being new flavonol diglycosides, and to the development of a dereplication strategy for the study of H. stoechas. In both species, an abundance of polyphenols was observed, which could be extracted with eco-friendly methods like SFE. Both halophytes showed a strong biological potential as their extracts and molecules demonstrated antioxidant, anti-collagenase, anti-inflammatory and wound healing activities. Moreover, we initiated for the first time cell suspensions of A. maritima, and identified elicitors, such as methyl-jasmonate, which led to H. stoechas cell suspensions with an increased content in 3,5-dicaffeoylquinic acid, a bio-marker of anti-inflammatory activity. The production of bioactive molecules in "plant cell factories" could be scaled-up to enhance the valorization potential of both halophytes in dermocosmetics.
69

[en] THE VISIBILITY OF OFFSHORE TOOLS WITH RFID AND GPS ASSOCIATION: ECONOMIC JUSTIFICATION / [pt] A VISIBILIDADE DE FERRAMENTAS OFFSHORE COM A ASSOCIAÇÃO RFID E GPS: JUSTIFICATIVA ECONÔMICA

AYRES DE AZEVEDO FILHO 26 February 2019 (has links)
[pt] Essa dissertação apresenta as tecnologias de radiofrequência e geoposicionamento (RFID/GPS) associadas. A questão fundamental para esse estudo seria a implementação de um sistema baseado em RFID que permita o rastreamento de ferramentas especiais e a localização destas em tempo real. Essas ferramentas são usadas no processo para produção “offshore” de óleo e gás. Como se trata de investimento em uma tecnologia inovadora é relevante considerar a análise financeira do negócio e, portanto se recomenda o cálculo do Valor Presente Líquido (VPL) e consequentemente o retorno sobre o investimento (ROI). A análise econômica foi baseada em uma fase de operação onde há postergação do óleo e a inoperância com sonda, cujos custos são parâmetros que expressam valores em moeda mais significativos. Os resultados mostraram que o valor investido é recuperado em 4 anos e são potencializados quando há tendência de elevação no preço do óleo, alta produtividade do campo e redução dos custos decorrente da melhoria de equipamentos ou pelo aumento da demanda desses. Os resultados obtidos permitiram avaliar e comparar não apenas o retorno do investimento, como benefício de impacto, mas também perceber e avaliar os benefícios agregados à cadeia de valor que certamente vinculada a demanda pressionará a evolução de novas tecnologias em função de mudanças e procedimentos. / [en] This dissertation presents the radio frequency technologies and geopositioning (RFID and GPS) associated with it. The fundamental question for this study would be the implementation of a system based on RFID, which would allow the tracking and the location of these special tools in real time. These tools are used in the process for offshore production of oil and gas. As it comes to investment in innovative technology is relevant considering business and financial analysis, so it is recommended the calculation of the net present value (NPV) and therefore the return on investment (ROI). The economic analysis was based on a phase of operation where there is a delay of oil and ineptitude with the drilling rigs, which costs are parameters that express the most significant currency values. The results showed that the amount invested is recovered in 4 years and are enhanced when: there is a tendency to rise in price of oil, the field features high productivity and as there will be an increased demand and improvements in RFID equipment, the investment costs tend to decrease. The results obtained made it possible to evaluate and compare not only the return on investment, as the benefit of impact, but also realize and assess the benefits of value chain aggregates that certainly linked to the demand will put pressure on the evolution of new technologies in the light of changes and procedures.
70

The effect of cattle grazing on the abundance and distribution of selected macroinvertebrates in west Galveston Island salt marshes

Martin, Jennifer Lynn 30 September 2004 (has links)
The effect of cattle grazing on the abundance and distribution of vegetation, burrowing crabs (Uca rapax, Uca pugnax, and Sesarma cinereum), marsh periwinkles (Littoraria irrorata), horn snails (Cerithidea pliculosa), and salt marsh snails (Melampus bidentatus) was evaluated over four seasons (summer 2000, fall 2000, winter 2001, and spring 2001) in grazed and ungrazed treatments. A Galveston Island salt marsh adjacent to Snake Island Cove was sampled at five elevations, from the water's edge to the high tidal flats. Data were analyzed for statistical differences using a two-way ANOVA in SAS. Cattle grazing may affect the vegetation and macroinvertebrate communities in salt marshes through trampling and herbivory. Vegetation resources available to other herbivores are decreased by the direct consumption of plant material by cattle. Spartina alterniflora and Salicornia virginica heights were significantly greater in ungrazed treatments than grazed for every season in the edge, upper, and middle elevation zones. Total aerial vegetative cover was also reduced significantly in grazed treatments, with the greatest impact in the edge and upper marsh. In the ungrazed treatments, S. alterniflora stem density was significantly greater in edge elevations, while both S. virginica percent cover and stem density in the edge elevation was greater. Burrowing crab populations were greater in the upper marsh and edge habitat of ungrazed treatments, while significantly greater in most of the middle marsh habitats of the grazed treatment. Size of burrowing crabs was generally significantly greater in ungrazed treatments. Cerithidea pliculosa size decreased in grazed treatments, but population had an overall increase in grazed treatments. Littoraria irrorata had very few differences between treatments, although few specimens were found. Melampus bidentatus populations were too small to evaluate thoroughly. Macroinvertebrate populations could be used to assess the overall health of grazed salt marshes.

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