Tidal marshes serve as important “blue carbon” ecosystems that accrete large amounts of carbon with limited area. While much attention has been paid to the spatial variability of sedimentation within salt marshes, less work has been done to characterize spatial variability in marsh carbon density. Driven by tidal inundation, surface topography, and sediment supply, soil properties in marshes vary spatially with several parameters, including marsh platform elevation and proximity to the marsh edge and tidal creek network. We used lidar to extract these morphometric parameters from tidal marshes to map soil organic carbon (SOC) at the meter scale. Fixed volume soil samples were collected at four northeast U.S. tidal marshes with distinctive morphologies to aid in building our predictive models. Tidal creek networks were delineated from 1-m resolution topo-bathy lidar data using a semi-automated workflow in GIS. Sample distance to tidal creeks and flow distance to the marsh edge were then determined. Log-linear multivariate regression models were developed to predict soil organic content, bulk density, and carbon density as a function of these predictive metrics at each site and across sites. Results show that modeling salt marsh soil characteristics with morphometric inputs works best in marshes with simple, single creek morphologies. Distance from tidal creeks was the most significant model predictor. Addition of distance to the inlet and tidal range as regional metrics significantly improves cross-site modeling. Our process-based approach results in predicted total marsh carbon stocks comparable to previous studies but provides trade-offs to existing simplistic carbon mapping methods. Further, we provide motivation to continue rigorous mapping of soil carbon at fine spatial resolutions and to use these results to guide salt marsh restoration projects and aid in the development of carbon markets.

Suite aux grands changements qui bousculèrent la société, la fin du dix-neuvième siècle fut une période de grande instabilité pour l’Angleterre. Les anxiétés créées par ces bouleversements se reflétèrent dans une prolifération de la littérature Gothique. Bien que le genre soit généralement étudié en relation avec la peur, ce mémoire soutient que le gothique tire son essence d’un large éventail d’émotions — et, tout particulièrement, de la honte. Étroitement liée à la notion de moralité, la honte est profondément ancrée dans les codes sociaux et les conventions. Dans une société aussi conservatrice et rigoureusement structurée que celle de la fin de la période victorienne, la honte révèle les conflits auxquels les individus faisaient face, ainsi que leur manière de les gérer. Pour comprendre les dynamiques de ces enjeux et les valeurs à leur fondement, ce mémoire explore trois romans importants de l’époque : The Picture of Dorian Gray, de Oscar Wilde, The Beetle, de Richard Marsh et The Strange Case of Dr Jekyll and Mr Hyde de Robert Louis Stevenson. En se concentrant particulièrement sur la figure du monstre gothique, cette étude considère deux types de honte : interne et externe. Tandis que le portrait de Dorian Gray illustre le conflit interne du protagoniste, la créature de The Beetle offre un exemple de honte externe comme châtiment; enfin, le double dans Jekyll and Hyde expose la mécanique de coexistence des hontes externe et interne. Au moyen de cet angle d’analyse, ce mémoire ouvre alors de nouvelles perspectives d’études sur la littérature gothique de la fin du dixneuvième siècle. / The end of the nineteenth century in England was a period of great instability as society experienced significant changes. These disruptions created anxieties, which were manifested in the proliferation of Gothic literature. While the Gothic genre is generally studied through the lens of fear, this thesis argues that it is governed by a range of affects, especially shame. Closely linked with morality, shame is deeply embedded in social codes and conventions. In a rigidly structured, conservative society such as that of late Victorian Britain, shame reveals much about the struggles that people faced and how they handled them. To understand the dynamics of these struggles and the values that underpinned them, this thesis explores three major novels from the fin de siècle period: The Picture of Dorian Gray by Oscar Wilde, The Beetle by Richard Marsh and The Strange Case of Dr Jekyll and Mr Hyde by Robert Louis Stevenson. With a particular focus on the figure of the Gothic monster, this study considers two different types of shame, internal and external. The portrait in Dorian Gray illustrates the internal conflict of the protagonist, while the creature in The Beetle offers an example of external shame as punishment. Meanwhile, the double in Jekyll and Hyde provides an opportunity to understand how internal and external shame coexist. In so doing, this thesis provides new insights into Gothic literature of the fin de siècle.

À travers une discussion des cinq principaux domaines théoriques qui influencent mon travail artistique; la biophilie, l’écoféminisme, «foraging» (la récupération), la non-dualité et l’espace sacré, j'explore les relations synergiques entre mes réflexions socioécologiques et politiques et ma pratique artistique. Je m'intéresse aux intersections entre l'activisme et l'art, l'engagement et la transformation, et l'idée que l'art peut être vu comme une «sculpture sociale» pour emprunter à Beuys. À la recherche constante des réalités alternatives des forces polarisantes qui dominent notre (ma) vision du monde contemporain et en critiquant la division sociétale de culture - nature, mon texte raconte la connectivité entre mes projets artistiques et mes recherches théoriques, définissant enfin la relation entre les deux comme fondamentale pour mon processus de création. Le concept de seuil est primordial, proposé comme lieu de rencontre ou jonction des mondes binaires; l'intime et le public, le profane et le sacré, la culture et la nature. / Through a discussion of the five main theoretical domains that influence my art-making; biophilia, ecofeminism, foraging (recuperation), non-duality and sacred space, I explore the synergistic relations between my socio-ecological-political reflections and my art practice. I am interested in the intersections between activism and art, engagement and transformation, and the idea that art can be seen as a “social sculpture” to borrow from Beuys. Continually seeking alternative realities from the polarizing forces that dominate our (my) contemporary world-view and questioning the culture - nature divide, my text chronicles the connectivity between my art projects and my theoretical research, finally understanding the relationship between the two as fundamental to my creative process. The concept of the threshold is paramount, proposed as a meeting place or juncture between binary worlds; the intimate and the public, the secular and thesacred, culture and nature.

Os objetivos deste estudo foram: 1) avaliar por meio da análise elementar (C, N, H, S, O), Ressonância Paramagnética Eletrônica (RPE), e Espectroscopia de Infravermelho com Transformada de Fourier (FTIR) às características dos ácidos húmicos (AHs) extraídos do solo do manguezal de Pai Matos (Cananéia-SP-BR) sob diferentes tipos de vegetação (Rhizophora mangle, Avicennia schaueriana, Laguncularia racemosa, Spartina alterniflora) e condições de redução, bem como às características dos AHs extraídos do solo de marismas espanholas também sob diferentes tipos de vegetação (Galícia: Spartina maritima, Juncus maritimus e Phragmites australis; Valência: Phragmites australis e Scirpus maritimus) e condições de redução; e 2) avaliar por meio da Pirólise-associada à cromatografia gasosa/espectrometria de massas (Pi-CG/EM) às características da matéria orgânica (MO) extraída do solo destes ecossistemas sob os mesmos tipos de vegetação e condições e redução. O carbono orgânico total, o nitrogênio total, o enxofre total e os valores de Eh e pH dos solos estudados também foram analisados. Os resultados mostraram que o ambiente predominantemente redutor dos solos estudados ocasionou uma maior incorporação de N e S e uma menor concentração de radicais livres semiquinona (CRLS) em relação aos AHs derivados de solos de ecossistemas terrestres, sugerindo desta forma, a presença de uma matéria orgânica (MO) menos humificada no solo das áreas de estudo; entretanto, somente os AHs extraídos do solo do manguezal apresentaram uma maior razão atômica H/C e O/C em relação aos AHs derivados de solos terrestres. A CRLS também foi maior nos AHs das camadas subsuperficiais dos solos estudados, sugerindo que o ambiente mais anóxico ocasionou um maior grau de humificação da MOS destas camadas, entretanto, como os manguezais e as marismas são ambientes de sedimentação, a contribuição de uma matéria orgânica mais humificada de origem terrestre previamente depositada nas áreas de estudo também pode ter ocasionado este resultado. Entre as diferentes vegetações estudadas, foi observada uma maior relação C/N e CRLS dos AHs extraídos do solo sob Rhizophora e Avicennia (manguezal) e uma maior relação C/N dos AHs extraídos do solo da marisma de Valência-ES, sugerindo uma maior recalcitrância da MOS sob estas vegetações. Os espectros de FTIR não permitiram verificar variações significativas na composição química e estrutural dos AHs obtidos dos solos sob as diferentes vegetações e condições de redução; entretanto, observo-se através da Pi-CG/EM uma maior concentração de compostos lignificados na MO extraída do solo sob Avicennia e Rhizophora (manguezal) e da marisma de Valência-ES, também sugerindo uma maior recalcitrância e menor humificação da MOS destas áreas de estudo. Além disso, observou-se que a maior decomposição da MOS ocasionou o decréscimo no conteúdo de lignina com o acréscimo relativo de compostos alifáticos; o acréscimo dos compostos alifáticos de cadeia curta em detrimento ao acúmulo dos de cadeia longa; a perda da dominância dos alcanos/alquenos de cadeias ímpares em relação aos de cadeias pares; e o acréscimo de compostos orgânicos de origem microbiana nos solos estudados. / The goals of this study were: 1) evaluate by elemental analysis (C, N, H, S, O), Electronic Paramagnetic Resonance (EPR), and Fourier transformed infrared spectroscopy (FTIR) the characteristics of the humic acids (HA) extracted from the soil of Pai Matos mangrove forest (Cananéia, SP, BR) under different vegetation types (Rhizophora mangle, Avicennia schaueriana, Laguncularia racemosa, Spartina alterniflora) and soil reduction conditions, as well as the HA extracted from Spanish salt marsh soils (Galícia and Valência) under different vegetation types (Galicia: Spartina maritima, Juncus maritimus, and Phragmites australis; Valencia: Phragmites australis e Scirpus maritimus) and soil reduction conditions; and 2) evaluate by Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique the characteristics of the SOM extracted from the these study areas under the same vegetation types and reduction condition. The total organic carbon, the total nitrogen, the total sulfur, and the soil pH and Eh in the field also were analyzed. The results showed that the predominantly anoxic soil condition caused the higher N and S content in the HA of both study areas than the HA derived from terrestrial soils and marine environments, and that the studied HA also showed a lower semiquinone-type free radical (SFR) content than terrestrial soils, thus suggesting a lower humification degree of the SOM derived from the study areas; however, only the HA derived from de mangrove forest soil showed a higher H/C and O/C atomic ratio than the HA derived from the terrestrial soils and marine environments. In addition, the SFR content also was lower in the surface soil layers, suggesting the input of a fresh and labile plant-derived organic matter as responsible by the lower humification degree of the SOM derived from these layers; however, as mangroves and salt marshes are sedimentation environments, it is likely that besides the more anoxic soil condition, a more humified organic matter (OM) derived from terrestrial soils also may cause the highest SFR content observed in the subsurface soil layers. Among the different vegetation types, also was observed a higher C/N ratio of the soil and HA derived from Valencian salt marsh, as well as both a higher C/N ratio and SFR content in the HA extracted from the soil under Rizhophora and Avicennia (mangrove), suggesting a more recalcitrant SOM in these sites. The FTIR spectras did not show significant variation among vegetation types and soil depths, and finally, by the Py-GC/MS technique was observed that the OM derived from the Valencian salt marsh soils and from the soil under Avicennia and Rhizophora (mangrove) showed a more recalcitrant SOM (higher lignin content) than the SOM derived from the soil under the other vegetation types studied. In addition, it was also observed that the SOM decomposition caused a decrease in lignin contents and a relative increase in aliphatics; an increase in short-chain aliphatics at the expense of longer ones; a loss of odd-over-even dominance in the n-alkanes and n-alkenes; and an increase in microbial products in the studied soils.

Os objetivos deste estudo foram: 1) avaliar por meio da análise elementar (C, N, H, S, O), Ressonância Paramagnética Eletrônica (RPE), e Espectroscopia de Infravermelho com Transformada de Fourier (FTIR) às características dos ácidos húmicos (AHs) extraídos do solo do manguezal de Pai Matos (Cananéia-SP-BR) sob diferentes tipos de vegetação (Rhizophora mangle, Avicennia schaueriana, Laguncularia racemosa, Spartina alterniflora) e condições de redução, bem como às características dos AHs extraídos do solo de marismas espanholas também sob diferentes tipos de vegetação (Galícia: Spartina maritima, Juncus maritimus e Phragmites australis; Valência: Phragmites australis e Scirpus maritimus) e condições de redução; e 2) avaliar por meio da Pirólise-associada à cromatografia gasosa/espectrometria de massas (Pi-CG/EM) às características da matéria orgânica (MO) extraída do solo destes ecossistemas sob os mesmos tipos de vegetação e condições e redução. O carbono orgânico total, o nitrogênio total, o enxofre total e os valores de Eh e pH dos solos estudados também foram analisados. Os resultados mostraram que o ambiente predominantemente redutor dos solos estudados ocasionou uma maior incorporação de N e S e uma menor concentração de radicais livres semiquinona (CRLS) em relação aos AHs derivados de solos de ecossistemas terrestres, sugerindo desta forma, a presença de uma matéria orgânica (MO) menos humificada no solo das áreas de estudo; entretanto, somente os AHs extraídos do solo do manguezal apresentaram uma maior razão atômica H/C e O/C em relação aos AHs derivados de solos terrestres. A CRLS também foi maior nos AHs das camadas subsuperficiais dos solos estudados, sugerindo que o ambiente mais anóxico ocasionou um maior grau de humificação da MOS destas camadas, entretanto, como os manguezais e as marismas são ambientes de sedimentação, a contribuição de uma matéria orgânica mais humificada de origem terrestre previamente depositada nas áreas de estudo também pode ter ocasionado este resultado. Entre as diferentes vegetações estudadas, foi observada uma maior relação C/N e CRLS dos AHs extraídos do solo sob Rhizophora e Avicennia (manguezal) e uma maior relação C/N dos AHs extraídos do solo da marisma de Valência-ES, sugerindo uma maior recalcitrância da MOS sob estas vegetações. Os espectros de FTIR não permitiram verificar variações significativas na composição química e estrutural dos AHs obtidos dos solos sob as diferentes vegetações e condições de redução; entretanto, observo-se através da Pi-CG/EM uma maior concentração de compostos lignificados na MO extraída do solo sob Avicennia e Rhizophora (manguezal) e da marisma de Valência-ES, também sugerindo uma maior recalcitrância e menor humificação da MOS destas áreas de estudo. Além disso, observou-se que a maior decomposição da MOS ocasionou o decréscimo no conteúdo de lignina com o acréscimo relativo de compostos alifáticos; o acréscimo dos compostos alifáticos de cadeia curta em detrimento ao acúmulo dos de cadeia longa; a perda da dominância dos alcanos/alquenos de cadeias ímpares em relação aos de cadeias pares; e o acréscimo de compostos orgânicos de origem microbiana nos solos estudados. / The goals of this study were: 1) evaluate by elemental analysis (C, N, H, S, O), Electronic Paramagnetic Resonance (EPR), and Fourier transformed infrared spectroscopy (FTIR) the characteristics of the humic acids (HA) extracted from the soil of Pai Matos mangrove forest (Cananéia, SP, BR) under different vegetation types (Rhizophora mangle, Avicennia schaueriana, Laguncularia racemosa, Spartina alterniflora) and soil reduction conditions, as well as the HA extracted from Spanish salt marsh soils (Galícia and Valência) under different vegetation types (Galicia: Spartina maritima, Juncus maritimus, and Phragmites australis; Valencia: Phragmites australis e Scirpus maritimus) and soil reduction conditions; and 2) evaluate by Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique the characteristics of the SOM extracted from the these study areas under the same vegetation types and reduction condition. The total organic carbon, the total nitrogen, the total sulfur, and the soil pH and Eh in the field also were analyzed. The results showed that the predominantly anoxic soil condition caused the higher N and S content in the HA of both study areas than the HA derived from terrestrial soils and marine environments, and that the studied HA also showed a lower semiquinone-type free radical (SFR) content than terrestrial soils, thus suggesting a lower humification degree of the SOM derived from the study areas; however, only the HA derived from de mangrove forest soil showed a higher H/C and O/C atomic ratio than the HA derived from the terrestrial soils and marine environments. In addition, the SFR content also was lower in the surface soil layers, suggesting the input of a fresh and labile plant-derived organic matter as responsible by the lower humification degree of the SOM derived from these layers; however, as mangroves and salt marshes are sedimentation environments, it is likely that besides the more anoxic soil condition, a more humified organic matter (OM) derived from terrestrial soils also may cause the highest SFR content observed in the subsurface soil layers. Among the different vegetation types, also was observed a higher C/N ratio of the soil and HA derived from Valencian salt marsh, as well as both a higher C/N ratio and SFR content in the HA extracted from the soil under Rizhophora and Avicennia (mangrove), suggesting a more recalcitrant SOM in these sites. The FTIR spectras did not show significant variation among vegetation types and soil depths, and finally, by the Py-GC/MS technique was observed that the OM derived from the Valencian salt marsh soils and from the soil under Avicennia and Rhizophora (mangrove) showed a more recalcitrant SOM (higher lignin content) than the SOM derived from the soil under the other vegetation types studied. In addition, it was also observed that the SOM decomposition caused a decrease in lignin contents and a relative increase in aliphatics; an increase in short-chain aliphatics at the expense of longer ones; a loss of odd-over-even dominance in the n-alkanes and n-alkenes; and an increase in microbial products in the studied soils.

Die Anpassung von Küstenniederungen, Seemarschen und Inseln an klimatische Veränderungen und einen steigenden Meeresspiegel ist eine der großen Herausforderungen des 21. Jahrhunderts. Im Gegensatz zu eingedeichten Küstenmarschen und Inseln besitzen tidebeeinflusste Seemarschen ein natürliches Anpassungspotential an sich verändernde hydrologische Rahmenbedingungen. Überflutungsabhängige Sedimenteinträge führen zu einem Anwachsen der Marschoberfläche und kompensieren somit einen Anstieg des Meeresspiegels. Die 10 verbliebenen nordfriesischen Halligen (Schleswig-Holstein, Deutschland) (Kapitel 1) sind bewohnte Inselmarschen, welche aufgrund ihrer anthropogenen Überprägung von naturbelassenen Seemarschen unterschieden werden müssen. Diese umfasst z.B. den Bau von flachen Sommerdeichen und Sielanlagen. Inwiefern sich diese Veränderungen auf die Sedimentdynamik der Marschen auswirken, ist bislang unzureichend belegt, was eine fundierte Diskussion bezüglich zukünftiger Entwicklungsperspektiven der Halligmarschen verhindert. Die vorliegende Arbeit ist dazu angelegt, diese Wissenslücke zu schließen. Sie untersucht das vertikale Marschwachstum exemplarisch auf den Halligen Hooge, Langeneß und Nordstrandischmoor und beurteilt deren Anpassungsvermögen an einen steigenden Meeresspiegel. Darüber hinaus werden zukünftige Entwicklungsperspektiven diskutiert. Um Faktoren und Prozesse, welche maßgeblich die Sedimentdynamik der Halligen beeinflussen, messbar zu machen, musstengeeignete Methoden entwickelt und angewendet werden. Zur Berechnung jährlicher Überflutungshäufigkeiten wurden Pegelschwellenwerte für Überflutungsereignisse auf Basis von digitalen Geländemodellen (DGMs) und d-GPS (differential global positioning system) Messungen errechnet und auf die verfügbaren, regionalen Pegeldaten angewendet (Kapitel 2). Sedimentfallen, bestehend aus LDPE (low density polyethylene) Flaschen (1 Liter) und Kunstrasenmatten (20 x 30 cm), bilden die Grundlage einer dreijährigen (November 2010 – März 2013) Feld- und Laborstudie zur zeitlichen und räumlichen Erfassung der sturmflutabhängigen Sedimentdeposition (Kapitel 3). Durch die Verwendung regionaler bodenphysikalischer Parameter (Lagerungsdichte und Gehalt an organischer Bodensubstanz) können Depositionsraten in eine vertikale Wachstumskomponente transformiert werden. Dazu werden Ergebnisse einer Rammkernsondierung genutzt, welche 12 Sedimentkerne mit einer Länge von maximal 100 cm umfasst. Die Sedimentbohrkerne sind weiterhin die Grundlage für eine 137Cs- und 210Pb-Datierung. Die Kombination beider Datensätze (Kapitel 4) ermöglicht einen schlüssigen Vergleich der Marschentwicklung seit dem Jahr 1915 mit regionalen Pegeldaten und Projektionen des zukünftigen Meeresspiegelanstiegs. Die Analyse der verfügbaren Pegeldaten (Kapitel 2) zeigt eine hohe Variabilität der jährlichen Überflutungshäufigkeiten. Das zehnjährige Mittel eintretender Ereignisse beträgt 2 Überflutungen auf Hooge, 9 – 10 Überflutungen auf Langeneß und 15 Überflutungen auf Nordstrandischmoor. Aufgrund der künstlichen Überhöhung der Marschkante durch Sommerdeiche mit + 1.54 m ü. mittlerem Tidehochwasser (MThw) auf Hooge und + 0.98 m ü. MThw auf Langeneß werden die betreffenden Halligen lediglich bei selten eintretenden Sturmflutereignissen überflutet. Die Höhe des wasser- und sedimentundurchlässigen Steinpflasters auf Nordstrandischmoor beträgt lediglich + 0.7 m ü. MThw. Die methodischen Untersuchungen bezüglich der Nutzung von Sedimentfallen (Kapitel 3) zeigen, dass beide Typen von Sedimentfallen vergleichbare Ergebnisse liefern. Oberhalb einer Depositionsrate von ~ 2.0 kg/m2 sinkt das Rückhaltevermögen der Kunstrasenmatte im Vergleich zur LDPE Flasche deutlich ab. Die parallele Nutzung beider Fallentypen, insbesondere wenn die Depositionsraten den Schwellenwert (~ 2.0 kg/m2) nicht überschreiten, erlaubt: (1) Die Überprüfung, ob beide Datensätze konsistent sind. (2) Die Identifizierung von Ausreißern. (3) Eine Abschätzung, ob Sediment auf oder in der Sedimentfalle nach der Überflutung remobilisiert wird. Um die Sedimentdeposition in eine vertikale Wachstumsrate zu übersetzen, muss die mittlere Bodendichte als auch der Gehalt an organischer Bodensubstanz des Marschbodens berücksichtigt werden. Die Bohrkernuntersuchungen zeigen, dass diese bodenphysikalischen Parameter auf den unterschiedlichen Halligen stark variieren. Marschen, die häufig überflutet werden lagern weniger organisches Material im Oberboden ein als selten überflutete Marschen. Niedrige Gehalte an leichten organischen Materialien geringer Dichte resultieren wiederum in einer höheren Lagerungsdichte des Marschbodens (Hooge 0.64 g/cm3, Langeneß 0.67 g/cm3, Nordstrandischmoor 0.83 g/cm3). Autochthones organisches Material (welches primär von der Halligvegetation stammt) trägt mit einem Anteil von 9.0 ± 1.4 % (Hooge) bis 21.4 ± 6.6 % (Nordstrandischmoor) zum Marschwachstum bei. Die Ergebnisse der Sedimentfallenuntersuchungen als auch der Datierungen zeigen deutlich ein Ungleichgewicht zwischen Marschwachstum und Meeresspiegelanstieg seit Beginn des 20. Jahrhunderts. Die langjährigen Wachstumsraten, basierend auf der 210Pb-Datierung, liegen mit 1.0 ± 0.3 mm/a auf Hooge, 1.2 ± 0.3 mm/a auf Langeneß und 2.6 ± 0.9 mm/a auf Nordstrandischmoor deutlich unterhalb des MThw-Anstiegs von 5.0 ± 0.3 mm/a (1951 – 2011, Wyk auf Föhr). Projektionen des Meeresspiegelanstiegs bis zum Jahr 2100 (Berechnet durch das fwu, Siegen) weisen darauf hin, dass extreme Wasserstände (höchste, jährliche Tidehochwasserstände, HThw, 6.6 ± 3.8 mm/a) deutlich schneller ansteigen werden als das MThw oder der mittlere Meeresspiegel (2.6 ± 0.4 mm/a). Aufgrund dieser Beobachtungen ist von einem zukünftigen Anstieg des Gefährdungspotentials für die Halligen auszugehen, wenn es nicht gelingt, ein sedimentologisches Gelichgewicht zwischen Meeresspiegel und Marschwachstum herzu stellen. Der Anstieg der Wellenhöhe und Periode, aufgrund von steigender Wassertiefe und einer geringeren Wellentransmissionsrate an den Sommerdeichen, resultiert in einer steigenden hydrodynamischen Belastung der Warften und der Marschoberfläche. Das sedimentäre Ungleichgewicht, besonders auf Hooge und Langeneß, kann eindeutig auf das hydrologische Management der Halligen zurückgeführt werden. Aus sedimentologischer Sicht sind die beiden Hauptkritikpunkte (1) die geringe Anzahl an Überflutungen aufgrund der Deichanlagen und (2) der eingeschränkte Transport suspendierter Feststoffe über die Binnenpriele. Letzteres resultiert aus der Blockade der Binnenpriele durch Sielanlagen und führt zu einer Abnahme der Sedimentdeposition mit zunehmender Entfernung zur Uferlinie. Um dem Ungleichgewicht zwischen Marschwachstum und Meeresspiegelanstieg entgegenzuwirken, ist es dringend erforderlich, neue Managementstrategien für die Halligen zu entwickeln (Kapitel 6), welche sedimentologische/geomorphologische Aspekte sowie die speziellen Bedürfnisse der Halligbevölkerung gleichermaßen berücksichtigen. Letztere beinhalten die Minimierung ökonomischer Schäden wie etwa Einschränkungen der landwirtschaftlichen Nutzung oder des Tourismus. Mögliche Szenarien können ein Abflachen der bestehenden Deiche oder deren Rückbau und Erneuerung durch wasser- und sedimentdurchlässige Rauhstreifen (z.B. Elastocoast®, BASF) beinhalten. Weiterhin erscheint die Reaktivierung der blockierten Binnenpriele eine plausible Maßnahme zu sein. Erste Freilandexperimente auf Hallig Langeneß (Kapitel 5) belegen einen erhöhten Sedimenttransport in die Binnenmarsch aufgrund geöffneter Sielanlagen in Verbindung mit Windstau (Thw-Ereignisse über Springtideniveau). Ob die generelle Umsetzung derartiger Maßnahmen möglich ist, ist in erster Linie davon abhängig, ob die Halligbevölkerung derartigen Veränderungen ihrer Umwelt aufgeschlossen gegenübersteht und diese lokalpolitisch getragen werden. Auf jeden Fall ist ein Umdenken dahingehend erforderlich, die halligtypischen Überflutungen (Land-Unter) nicht ausschließlich als Bedrohung zu verstehen. Sie sind ein natürliches Phänomen, welches notwendig ist, um das Gleichgewicht zwischen Meeresspiegelanstieg und Sedimentdeposition aufrechtzuerhalten.

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-05-05T13:45:21Z No. of bitstreams: 1 marcoaurelioalvespereira.pdf: 7599008 bytes, checksum: 48e04292d562d8084f38167b184afde1 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-17T13:39:25Z (GMT) No. of bitstreams: 1 marcoaurelioalvespereira.pdf: 7599008 bytes, checksum: 48e04292d562d8084f38167b184afde1 (MD5) / Made available in DSpace on 2017-05-17T13:39:25Z (GMT). No. of bitstreams: 1 marcoaurelioalvespereira.pdf: 7599008 bytes, checksum: 48e04292d562d8084f38167b184afde1 (MD5) Previous issue date: 2010-03-26 / O cervo-do-pantanal (Blastocerus dichotomus) é um mamífero de grande porte, sendo considerado o maior cervídeo nativo da America do Sul. Esta espécie encontra-se extinta em 60% da sua área de distribuição histórica que compreendia as várzeas naturais dos grandes rios entre o sul do Amazonas e o norte da Argentina. Apesar de se encontrar ameaçado de extinção, pouco se sabe acerca dos aspectos ecológicos do cervo-do-pantanal. Nesse contexto, o presente estudo, busca investigar a sazonalidade no comportamento espacial desta espécie, como também analisar informações relacionadas à fidelidade de habitat e relações intra-específicas através da sobreposição de áreas núcleo. Para tanto o mesmo contém uma revisão introdutória e dois capítulos abordando os seguintes temas: 1- estudo comparativo para o efeito da sazonalidade entre animais reintroduzidos e ou nascidos na Estação Ecológica de Jataí (EEJ) e animais de população natural, localizados na bacia do rio Paraná; 2- relações espaciais através da sobreposição de áreas núcleo para animais reintroduzidos e ou nascidos na EEJ. Ao todo 39 cervos-do-pantanal marcados sendo 9 da área de reintrodução e 30 da área de população natural, contribuíram para as análises do presente trabalho. Os resultados revelam que ambas as populações estudadas tiveram áreas de vida maiores para machos do que para fêmeas, o que pode ser reflexo das diferenças nas estratégias de utilização do ambiente por indivíduos de ambos os sexos. Para os animais da EEJ as áreas estimadas para a estação chuvosa geralmente foram menores do que as estabelecidas na seca, já para os animais da bacia do rio Paraná observou-se uma inversão na ordem desses valores, ou seja, a média na estação chuvosa foi maior do que a média no período de seca. Tal inversão pode estar relacionada com a dinâmica das características ambientais promovida pela sazonalidade para cada região. A análise de fidelidade de habitat na área de reintrodução revelou uma sobreposição de suas áreas núcleos estimada para as duas estações seca e chuvosa, com fêmeas apresentando porcentagem de fidelidade maior do que machos. A análise envolvendo a sobreposição de áreas núcleo entre os animais desta região revelaram que dois animais, sendo um macho e uma fêmea, sobrepuseram seus núcleos de atividade mesmo quando estimados com concentração média harmônica (30%) de distribuição de utilização das localizações espaciais. Os dados utilizados neste trabalho fazem parte dos resultados obtidos pelo Projeto Cervo-do-Pantanal de Porto Primavera, coordenado pelo NUPECCE (Núcleo de Pesquisa e Conservação de Cervídeos), localizado na Faculdade de Ciências Agrárias e Veterinárias FCAV/UNESP de Jaboticabal, como parte das ações compensatórias referente ao reservatório formado pela usina hidrelétrica Sérgio Motta ou “Porto Primavera”. / Marsh deer (Blastocerus dichotomus) is a large mammal and is considered the largest deer native to South America, this species is extinct in 60% of its historic range that included the natural flood plain of the great rivers between the southern Amazon and northern Argentina. Despite being threatened with extinction, little is known about the ecological aspects of deer marsh. In this context, this study aims to investigate the seasonality in the spatial behavior of this species, but also analyze information related to habitat use and intraspecific relations using overlapping core areas. To this end it contains a review and two introductory chapters covering the following topics: 1 - comparative study for the seasonality effect of reintroduced animals and / or born in the Ecological Station (EEJ) and animals natural population located in the River Paraná; 2 - spatial relations using overlapping core areas to reintroduced animals and / or born in the EEJ. A total of 39 deer-billed and 9 marked the reintroduction area and 30 in the area of natural population, contributed to the analysis of this work. The results show that both populations studied areas of life were higher for males than for females, which may reflect differences in strategies for using the environment of individuals of both sexes. For animals of the EEJ areas estimated for the rainy season were generally lower than those established in the dry season, as for animals of the Paraná River basin showed a reversal in the order of these values, ie, the average during the rainy season was higher than the average during the dry season. This reversal can be related to the dynamics of environmental characteristics promoted by the seasonal pattern for each region. The analysis of habitat use of reintroduction area revealed an overlap in their core areas estimated for both dry and wet seasons, with females showing higher percentage of fidelity than males. The analysis involving the overlap of core areas among the animals of this region revealed that two animals are one male and one female overlapped its core activity even when estimated harmonic mean concentration (30%) of distribution of use of spatial locations. The data used in this work are part of the results obtained by the Project Cervo-do-Pantanal de Porto Primavera, coordinated by NUPECCE (Núcleo de Pesquisa e Conservação de Cervídeos), located at the Faculdade de Ciências Agrárias e Veterinárias FCAV/UNESP de Jaboticabal, as part stock compensation related to the reservoir formed by the Sergio Motta or "Porto Primavera Dam.

The Florida Everglades ecosystem is threatened by human development, increased pollution, freshwater scarcity, and invasive species; factors that have negatively impacted the Everglades and native species health and populations. Man-made canals and levies have redirected the natural flow of fresh water from Lake Okeechobee into the Florida Everglades, starving central and south Florida ecosystems of necessary fresh water and nutrients. Through the efforts of the Comprehensive Everglades Restoration Project (CERP), freshwater is being redirected back into central and south Florida, returning the sheet flow of water back into the Everglades. Monitoring species abundance in the Everglades is a beneficial conservational tool for assessing restoration efforts from CERP. As a semi-aquatic apex predator, river otters (Lontra canadensis) are a useful health bio-indicator for the Florida Everglades. In order to conduct future population studies of river otters in the Florida Everglades, it must first be ascertained where they can be found and what time of year they are most likely to be sighted. For this study, Moultrie infrared game cameras were used to photograph the presence or absence of river otters within the five main habitats in the Everglades; the pinelands, hardwood hammock, cypress swamp, marsh prairie, and mangrove estuary at two protected areas in the Florida Everglades (Big Cypress National Preserve and Fakahatchee Strand State Park). River otters were most frequently sighted in the hardwood hammock habitat, but were also found in the cypress swamp. The large majority of river otter sightings occurred during dry season, which is thought to be a function of restricted water availability and aquatic mobility. Future population studies of river otters would be most productive in the hardwood hammock and cypress swamp habitats during dry season. Game camera images along with field opportunistic sightings, resulted in a variety of species documented. This provided valuable information of species richness and distribution within and amongst the habitats. The hardwood hammock was found to be the most species rich habitat, having over half the species observed in the study in this habitat. The Aves class was the most abundantly observed in the Everglades, and was most frequently sighted during the dry season. As a refuge for migratory birds, the Everglades house the majority of bird species during the winter months, which occur during dry season. The Aves class was most frequently sighted in the pinelands habitat during dry season. This habitat, being the highest in elevation and therefore the driest, shows a stronger resemblance to most northern bird habitats then does the water-saturated wetlands found throughout the Everglades. The mangrove estuary was the most commonly occurring outlier, having the least species overlap when compared to the other habitats. All other habitats in the Everglades are freshwater wetlands, while the mangrove estuary is a brackish environment, which limits the species that are unable to tolerate saline conditions. Further studies of species abundance throughout the Everglades will aid in monitoring CERP restoration efforts over time.

The spatial and temporal patterns in the ichthyofaunal community composition and structure in Taylor’s salt marsh and adjacent eelgrass beds (Zostera capensis) in the Kariega Estuary, was investigated every two months between May 2006 and March 2007. Total ichthyofaunal abundances and biomass in the salt marsh ranged between 0.55 and 21.7 ind.10m-2 and between 0.03 and 1.9 g.wwt.10m⁻², respectively. There were no significant spatial patterns in the values evident (P > 0.05 in all cases) although seasonal trends were marked, with highest values consistently recorded during the warmer summer months. Investigations into the community structure showed that the ichthyofaunal community within salt marsh was composed almost exclusively of juveniles of estuarine dependant (category II) species, mainly juvenile Mugilidae (<20mm SL) that comprised up to 83% of all fish sampled. Hierarchical cluster analysis and multidimensional scaling did not identify any distinct spatial patterns in the ichthyofaunal community within the salt marsh. The absence of any spatial patterns in the community structure could be related to the absence of any significant spatial patterns in the physico-chemical (temperature, salinity and dissolved oxygen concentrations) and biological (water column and microphytobenthic algal concentrations) variables within the salt marsh (P > 0.05 in all cases). Temporal shifts in the ichthyofaunal community structure within the salt marsh were, however, evident largely reflecting the breeding cycles of individual species within the sub-region. Within the adjacent eelgrass beds, total ichthyofaunal abundances and biomass ranged between 8.4 and 49.4 ind.10m⁻² and between 2.9 and 94.5 g.wwt.10m⁻², respectively. Once again there were no distinct spatial patterns in the abundance and biomass values evident although seasonal patterns were marked. In contrast to the salt marsh, within the in the eelgrass community, there were a large number of adult individuals recorded. Again category II species, the estuarine dependent species, were numerically and gravimetrically dominant. The dominance of category II species reflects the marine dominance of Kariega Estuary. The remaining estuarine utilisation categories did not contribute significantly to abundance or standing stock totals. Hierarchical cluster analysis showed that the salt marsh and eelgrass beds represented two distinct habitats within the Kariega Estuary. Within the salt marsh, the family Mugilidae were numerically dominant contributing 83% of the total catch. Within the eelgrass beds, the sparid, Rhabdosargus holubi and representatives of the family Gobidae contributed 36.3% and 33.9% respectively to the total catch. Estuaries with a wide range of microhabitats have been demonstrated to support a more diverse ichthyofaunal community. Shallow water habitats in general are important areas for juvenile fish within estuaries. Taylor’s salt marsh provides an alternative shallow water habitat, occupied by a distinct ichthyofaunal community composition, with increased food availability and decreased predation pressure, for a wide range of fish species.

Les prés-salés sont des interfaces complexes entre le milieu continental et maritime d'une grande importance environnementale. En contexte de changement climatique, ces zones vulnérables font maintenant l'objet d'une attention particulière. Cette étude porte sur la mesure et la compréhension de la dynamique des prés-salés soumis à un régime méga-tidal (marnage supérieur à 10 m), à travers l'étude de deux estuaires des côtes du Nord-Ouest de la France : l'estuaire du Couesnon en baie du Mont-Saint-Michel (MSM) et l'estuaire de la Somme. L'originalité de l'approche est de considérer une très large gamme d'échelles temporelles, depuis l'échelle séculaire jusqu'à l'événement de marée. A l'échelle séculaire, la mesure de l'évolution de la surface des prés salés en Baie de Somme, à partir de documents historiques et de photos aériennes, montre une évolution étonnamment similaire à celle de l'estuaire du Couesnon depuis la canalisation de la partie terminale de ces rivières au milieu du XIXème siècle. Après une phase de développement rapide des prés salés, une réduction concomitante des taux de croissance est observée dans les deux estuaires au début du XXème siècle. Nous proposons que l'augmentation du niveau marin à cette période soit responsable de cette réduction de croissance des prés-salés. L'analyse pluriannuelle des surfaces en baie de Somme met en évidence des périodes d'érosion des prés-salés résultant de la migration des chenaux tidaux à la frontière des prés-salés. Une étude sur 3 ans en baie du MSM a permis de caractériser le fonctionnement d'un chenal tidal sinueux en frontière des prés salés, grâce à des mesures topographiques inédites réalisées avec un Lidar terrestre haute résolution, combinées à des mesures hydro-sédimentaires. Des relevés journaliers durant les marées d'équinoxe de Septembre et de Mars ont mis en évidence une relation très non-linéaire entre érosion des berges et hauteur de marée. Cette relation est régie principalement par une forte augmentation des vitesses du courant lors du jusant. L'étude des taux d'accrétion dans la partie interne du méandre tidal a révélé l'importance de la présence de la végétation pionnière. Des lois empiriques de sédimentation et d'érosion en fonction de la hauteur de marée sont proposées. Il est montré que 6 % des marées les plus hautes de l'année sont responsables de 90 % de l'érosion des prés-salés par migration du chenal, alors que la sédimentation est dominée par les marées les plus fréquentes. Ces travaux mettent en évidence le rôle fondamental de la divagation des chenaux en marge des prés salés méga-tidaux. Leur dynamique est contrôlée principalement par les marées les plus importantes, dont la fréquence est régit par des cycles nodaux de 4,4 à 18,6 ans. Les données topographiques et hydro-sédimentaires inédites acquises durant ce travail de thèse fournissent des contraintes fortes pour le développement de modèle d'évolution des prés salés. / Salt marshes are complex interfaces between land and sea of high environmental values. Theses vulnerable landforms are now subjected to particular attention since they are very sensitive to sea level changes and storm events. This study focuses on salt marsh dynamic subjected to a mega-tidal range (higher than 10 m) that received less attention, through the study of two estuaries of the north-western coast of France: The Couesnon estuary in the Bay of Mont -Saint-Michel and the Somme estuary. The originality of this study is to consider a wide range of time scales, from the secular one to tide events. At secular time scale, we measure the evolution of salt marsh surfaces in the Somme bay, from historical documents and aerial photographs. The comparison with the Couesnon estuary reveals a surprisingly similar evolution of salt marsh extension, since the derivation and embankment of their main river in early mid XIXth century. After a period of rapid salt marsh extension, a concomitant reduction of growth rates is observed in both estuaries in the early XXth century. We propose that the increase in sea level rise during this period is responsible for the reduced growth of salt marshes. The pluriannual analysis highlights periods of erosion of salt marshes resulting from the tidal channels migration on salt marsh fringe. However, the pluriannual time scale does not capture the processes governing the dynamics of channel migration. This has motivated a 3 years study of a sinuous tidal channel located on the fringe of the marsh with the aim to understand its dynamics at daily to annual scales. We have acquired 36 high resolution topographic surveys with Terrestrial Laser Scanner. We used daily surveys during spring tides of various High Water Level (HWL) to analyze channel dynamics at tidal event timescales. Daily TLS measurements revealed a non-linear relationship between bank erosion and tidal height. This relationship is related to a sharp increase in flow velocities during the ebb (up to 2.2 m/s) for overmarsh tides. Spatially averaged accretion on the inner bend tends to increase linearly with HWL and is increased by a factor 2 during summer/autumn spring tides at the peak of pioneer vegetation development. We propose empirical laws of sedimentation and erosion depending on the tide height, which model that 6% of the highest tides of the year are responsible for 90 % of salt marsh erosion by channel migration, while sedimentation is dominated by frequent tides. These results highlight the need to incorporate the influence of vegetation on sedimentation rates as well as tidal migration processes in models of salt marsh dynamic in mega-tidal environment. Long term modeling should account for the highest tides of the year, that make tidal channel very sensitive to the nodal cycle (18.6 years) which controls the occurrence of the highest tides in mega-tidal environment.