Thèses sur le sujet « Coastal erosion Risk Management »

Climate change is causing serious threats on natural and human systems worldwide. In particular, climate-related impacts will be especially relevant in coastal areas, where a dense interaction between terrestrial and marine systems occur. Located at the land-sea interface, coastal areas, are dynamic environments where natural and anthropogenic forcing interact at diverse temporal and spatial scales modifying their geomorphological, physical and biological characteristics. Against this complex interplay, coastal managers and policy makers are increasingly asking for new integrated approaches supporting a multi-scenario analysis of environmental risks arising from natural and anthropic stressors. In the frame of this thesis, a GIS-based Bayesian Network (BN) approach was developed, exploiting functionalities offered by both methods to evaluate the probability (and related uncertainty) of coastal erosion risks, and connected water quality variation, against multiple ‘what-if’ scenarios, including different climate conditions (e.g. sea level rise). Resulting output of its application to the testing case of the shoreline of the municipality of Ugento (Apulia Region, Italy), represents valuable information to support robust decision-making and to provide the means for adaptive policy pathways in the context ICZM implementation and disaster risk reduction.

The main goal of this work is to provide a regional assessment of the coastal vulnerability of Sardinian sandy beaches to storm impacts. To do this we have assessed the geomorphic coastal vulnerability taking into account the intensity of storm induced hazards and the adaptation capacity of the system. The methodology aplied allows to calculate quantitatively -in a separate manner- the erosion and inundation hazards induced by the storms associated to a given probability of occurrence. The practical application of this method is to provide information that allows stakeholders to manage resource allocation and mitigate consequences. This framework has been developed by covering the following steps:(i). Define forcing conditions for the Sardinian coast using a storm classification method; to obtain this we have divided the Sardinian coast in 4 different sectors. For each sector storm events have been defined from hindcast wave data obtained for the period between 1979-2012. (ii) Find out the induced beach response to each storm class measured by the quantification of the flooding and erosion hazards. In each sector sandy beaches have been characterized in terms of their slope, height, widht and grain size. (iii) Estimation of a coastal vulnerability index formulated in terms of these two intermediate variables by means of a linear function that ranges from a minimum value of 0 (optimum state) to a maximum of 1 (failure state), defining 5 qualitative categories (Very Low, Low,. Medium, High, Very High). (iv) Assessment and mapping of the coastal vulnerability index along different sectors of the island. In terms of prospective analysis we have built a projected timeline of beach hazard based on existing storm data fitted into an extreme probability function. Once the probability of occurrence of the flooding and erosion hazards has been assessed and a risk level defined by the stakeholders, the spatial distribution of vulnerabilities associated to selected probability level will permit to "robustly" compare areas along the coast to identify the most endangered zones.

The geography of Scotland, with a highly undulating hinterland, long and indented coastline, together with a large number of islands, means that much social and economic activity is largely located at the coast. The importance of the coast is further highlighted by the large number of ecosystem services derived from the coast. The threat posed by climate change, particularly current and future sea level rise, is of considerable concern and the associated coastal erosion and coastal flooding has the potential to have a substantial effect on the socioeconomic activity of the whole country. Currently, the knowledge base of coastal erosion is poor, which serves to hinder the current and future management of the coast. This research reported here aimed to establish four key aspects of coastal erosion within Scotland: the physical susceptibility of the coast to erosion; the assets exposed to coastal erosion; the vulnerability of communities to coastal erosion; and the coastal erosion risk to those communities. Coastal erosion susceptibility was modelled here within a GIS, using data for ground elevation, rockhead elevation, wave exposure and proximity to the open coast. Combining these data produced the Underlying Physical Susceptibility Model (UPSM), in the form of a 50 m2 raster of national coverage. The Coastal Erosion Susceptibility Model (CESM) was produced with the addition of sediment supply and coastal defence data, which then moderates the outputs of the UPSM. Asset data for dwellings, key assets, transport infrastructure, historic assets, and natural assets were used along with the UPSM and CESM to assess their degree of exposure to coastal erosion. A Coastal Erosion Vulnerability Model (CEVM) was produced using Experian Mosaic Scotland (a geodemographic classification which identifies 44 different social groups within Scotland) to classify populations based upon 11 vulnerability variables. Dwellings were assigned a CESM and CEVM score in order to establish their coastal erosion risk. This research demonstrated that the issue of coastal erosion will impact on a relatively low number of properties compared to those impacted by flooding (both coastal and fluvial) as many dwellings are already protected by coastal defences. There is therefore, a considerable future liability, and great pressure for coastal defences to be maintained and upgraded in their current form. The use of the CEVM is a novel inclusion within a coastal erosion assessment for Scotland. Use of the CEVM established that coastal erosion risk is not distributed equally amongst the Scottish coastal population and highlighted that risk can be reduced by either reducing exposure or reducing vulnerability. Thus far in Scotland, reducing exposure has been the primary management approach, which has a number of implications with regards social justice. This research identified the existing data gaps that should be addressed by future research in order to further improve coastal management in Scotland. Future research should focus on assessing historical coastal change rates on a national scale, improve modelling of national scale wave exposure, enhance the information held about current coastal defences and, determine the direct and indirect economic cost associated with the loss of different asset types. It is also necessary to clarify the social justice implications of using adaptation approaches to manage coastal erosion as well as establishing a method to communicate the susceptibility, exposure, vulnerability and risk aspects whilst minimising the potential negative impacts (e.g. property blight) of releasing such information.

L’enjeu de cette étude est d’analyser comment le risque d’érosion côtière est appréhendé d’un point de vue juridique. Ce risque naturel se caractérise par une avancée progressive de la mer sur les terres, appelée à s’accentuer dans les prochaines décennies selon les derniers rapports scientifiques. Cependant, l’on observe que parallèlement à cela, les côtes métropolitaines accueillent une population de plus en plus grandissante ; se produit ainsi la rencontre de deux tendances antinomiques. Dès lors, l’objet de la présente étude est d’observer les conséquences juridiques résultant de cette confrontation. Par conséquent, afin de parvenir à la conciliation de ces différents enjeux, nous allons démontrer l’intérêt de faire évoluer les politiques publiques de gestion de l’érosion côtière en faveur d’une approche intégrée, selon les principes fondamentaux de la GIZC. Notre étude va ainsi proposer une traduction juridique de cette évolution
The aim of this study is to analyze how the risk of coastal erosion is apprehended at a legal point of view. This natural risk is characterized by a gradual encroachment of the sea on land, intending to grow in the coming decades according to the latest scientific reports. However, it is observed that beside this, the metropolitan coast are home to an increasingly growing population ; so we find the meeting of two contradictory trends. Therefore, the purpose of this study is to observe the legal consequences of this confrontation. So, in order to achieve the reconciliation of these issues, we will demonstrate the importance of the development of public policies for managing coastal erosion in favor of an integrated approach, based on fundamental principles of ICZM. Our study will thus provide a legal expression of this development

L’érosion des falaises meubles résulte de la dénudation progressive des formations superficielles héritées recouvrant les littoraux actuels. Leur recul est irrégulier et souvent plus modéré que le recul des littoraux d’accumulation. Ce type de falaise s’étend, en Bretagne, sur 20 % du linéaire côtier. Malgré une dynamique encore mal cernée, l’urbanisation et les activités humaines se sont densifiés à leur sommet et en arrière des versants au cours des dernières décennies. Leur érosion est donc étudiée dans cette thèse sous l’angle des risques côtiers générés par l’occupation actuelle des versants des falaises meubles régionales. L’analyse porte sur l’aléa, les enjeux exposés et la gestion afin d’évaluer le risque d’érosion et d’approcher la vulnérabilité de ces territoires.L’approche systémique vise, par emboitement d’échelles temporelles et spatiales, à identifier les composantes contribuant à augmenter la vulnérabilité de ces littoraux.Une chronique d’aléas sur les 20e et 21e siècles présente la répartition spatio-temporelle régionale de l’érosion et les facteurs générateurs. Sur six sites d’étude représentatifs, la photo-interprétation (entre 1950 et 2015) et un suivi photogrammétrique (de 2017 à 2019) quantifient les vitesses et les rythmes de recul des falaises meubles. La cartographie géomorphologique aboutit à un nouveau paradigme pour l’évaluation du risque d’érosion de ces littoraux. Enfin, des indicateurs d’enjeux et de gestion déterminent la vulnérabilité sur ces sites et une enquête régionale menée auprès des acteurs institutionnels identifie les dispositifs de gestion absents. Selon leur typologie, les falaises meubles sont diversement exposées à une érosion favorisée par les facteurs météo-marins combinés, incluant notamment les précipitations. En Bretagne, leur recul menace surtout des terrains résidentiels et agricoles. Les indicateurs de vulnérabilité mettent en évidence l’insuffisance des documents réglementaires, de stratégies locales, de concertation et de sensibilisation des citoyens. Ils permettent de mieux comprendre les difficultés posées par la gestion du risque d’érosion
The erosion of soft cliffs results from the denudation of inherited, superficial formations covering the current coastlines. Their retreat rate is unsteady and often smaller than on accumulation coasts. This type of cliffs represents, in Brittany, 20 % of the coastline. Although their evolution is not fully understood, urbanization and human activities have grown denser at the top of these soft cliffs and behind, in recent decades. This thesis addresses coastal erosion with a focus on coastal risks induced by current urbanization of these soft cliffs at regional scale. The analysis tackles the hazard, stakes and management components in order to assess erosion risk and to draw near the vulnerability of these territories.A systemic approach is adopted, nesting temporal and spatial scales, with the objective to identify the components contributing to the vulnerability of these coastal territories.A chronicle of erosion events at regional scale is produced to present the spatio-temporal distribution of erosion over the 20th and 21st centuries and to analyze the generating factors.Focusing on six representative sites, aerial photographs (between 1950 and 2015) and photogrammetric monitoring (from 2017 to 2019) allow a quantitative study of the kinematics of soft cliffs retreat. A new paradigm for assessing and mapping the erosion risk for soft cliffs is proposed.Finally, indicators for stakes and risk management allow assessing vulnerability at these sites, and a survey conducted among regional stakeholders identifies gaps in risk management policies. According to their type, soft cliffs show a range of erosion responses, controlled by a combination of subaerial and marine factors, including rainfall. In Brittany, their retreat threatens mainly residential and agricultural lands. The vulnerability indicators highlight the paucity of regulations, local management strategies, dialogue and public awareness. They allow a better understanding of the challenges raised by risk erosion management

The action of sea storms is one of the most complex littoral processes with deep management implications. Along the Catalan shoreline which is about 700 km long, 190 km are subject to erosion and/or flooding. Around one million people live in areas potentially affected. Sea Level Rise could exacerbate this problem in the near future. Reactive interventions have been the norm in coastal engineering and management. This dissertation proposes a pre-storm strategy that foster cost-effective eco-compatible measures, termed Quick Defence Measures (QDM). Pre-storm intervention requires to forecast the future post-storm state. Hence, the main objective of this thesis is to assess present coastal risk through a Coastal Early Warning System (CEWS), termed LIM-COPAS, that forecasts the more relevant episodic coastal hazards at the area. LIM-COPAS consists of four modules: (i) meteorological model; (ii) wave generation/propagation code; (iii) coupled morpho-hydrodynamic model and (iv) risk module via non-stationary multivariate probabilistic models. The performance of this suite of models has been tested with (i) a set of hindcast events and (ii) synthetic storm conditions. The hindcasted events have been: December 2008 (D-08); October-2015 (O-15); November 2015 (N-15); January 2016 (J-16); February 2016 (F-16); December 2016 (D-16) and January 2017 (J-17). In D-08, errors in nearshore spectral wave parameters have been about twice than those in the offshore area. The error was around 20% in hydrodynamics and 50% in morphodynamics. The post-storm response has been acceptably reproduced, with a Brier Skill Score near 0.4. LIM-COPAS has shown good accuracy with high return period events (i.e. Tr,waves > 10 yrs, D-16 and J-17), but lower agreement was found for milder storms (i.e. O-15 and F-16). The meteorological module provided wind fields that were systematically overestimated. The integrated Mean Bias (MB) was -1.52 ± 0.78 m/s. Tarragona (Coefficient of Efficiency, COE = 0.27 ± 0.13) and Begur (COE = 0.29 ± 0.17) had metrics above the average value (COE = 0.24 ± 0.14); but lower agreement was found at Mahón (COE = 0.13 ± 0.16) and Dragonera. Wave metrics were more accurate than for the wind fields. The integrated Hs COE was 0.52±0.12 and Tm02 COE was 0.36±0.14. At the central coast, Hs has presented good metrics: low MB (-0.06 ± 0.08 m) and high COE (0.58 ± 0.11). The northern coast metrics were the most stable. The newly developed risk module has been implemented at 79 beaches. Erosion has been estimated as a bounded cost, whereas flooding as a high upside cost. Dissipative beaches tend to exhibit higher costs than reflective beaches under high sea levels. Tr,waves < 10 yrs events joint with storm-surges can lead to significant damage costs. The estimated losses for the N-15 event (2510·10^3 euros) do not differ excessively from J-17 (3200·10^3 euros). Two types of QDM have been numerically tested: (i) sand dunes and (ii) geotextile detached breakwaters. The benefits from maintaining the sand volumes outperform the flooding cost reduction. In general terms, the detached breakwater can be a suitable option for beaches in an intermediate morphodynamic state against low to moderate sea levels and high wave return periods. At dissipative beaches, dunes are the best option, but they require a minimum beach width (around 30 m) that ensures their lifetime. QDM functionality can be enhanced with compatible long-term actions (nourishments, sand bypasses, submerged vegetation, etc.). A healthy beach state is paramount for the QDM effectiveness. A higher sustainable management under present and future climate can be reached with the joint combination of (i) CEWS as a short-term forecasting tool; (ii) QDM that mitigate storm impacts and (iii) long-term interventions that improves the beach health.
La acción de los temporales de mar es uno de los procesos litorales más complejos, con profundas implicaciones en la gestión del litoral. A lo largo de la línea de costa catalana, 190 km están sometidos a erosión y/o inundación. Cerca de un millón de personas viven en áreas potencialmente afectadas. La tradición en ingeniería y gestión costera han sido intervenciones reactivas. Esta tesis propone una estrategia pre-tormenta que fomente una serie de medidas eco-compatibles, denominadas Medidas de Acción Rápida (MAR). Las intervenciones pre-tormenta requieren predecir el estado post-temporal de la costa. Por tanto, el principal objetivo de esta tesis es evaluar el riesgo costero episódico mediante un Sistema de Alarma Temprana Costero (CEWS), denominado LIM-COPAS, que predice las peligrosidades costeras más relevantes en dicha área. LIM-COPAS consiste de cuatro módulos: (i) modelo meteorológico; (ii) código de generación/propagación del oleaje; (iii) modelo acoplado morfo-hidrodinámico y (iv) un módulo de riesgo vía modelos probabilísticos multivariantes y no-estacionarios. El comportamiento de estos módulos ha sido analizado mediante (i) una serie de eventos pasados y (ii) temporales sintéticos. Los eventos pasados han sido: Diciembre 2008 (D-08); Octubre 2015 (O-15); Noviembre 2015 (N-15); Enero 2016 (J-16); Febrero 2016 (F-16); Diciembre 2016 (D-16) y Enero 2017 (J-17). En D-08, los errores en los parámetros espectrales de oleaje costero han sido casi el doble que en mar abierto. El error ha sido del 20% en la hidrodinámica y del 50% en la morfodinámica. La respuesta post-temporal ha sido reproducida aceptablemente, con Brier Skill Score cercanos a 0.4. LIM-COPAS ha demostrado buena precisión con tormentas de alto período de retorno (i.e. Tr,waves _ 10 yrs, D-16 y J-17), pero menor concordancia fue encontrada para las tormentas moderadas (i.e. O-15 y F-16). El módulo meteorológico estimó campos de viento que fueron sistemáticamente sobreestimados. El Sesgo Medio (MB) integrado fue de −1,52 ± 0,78 m/s. Tarragona (Coeficiente de Eficiencia, COE = 0,27±0,13) y Begur (COE = 0,29±0,17) tuvieron métricas por encima de la media (COE = 0,24±0,14); no obstante, peor ajuste se encontró en Mahón (COE = 0,13 ± 0,16) y Dragonera. Las métricas de oleaje fueron más precisas que las del viento. Hs COE integrada fue 0,52±0,12 y Tm02 COE fue 0,36±0,14. En la costa central, Hs presentó buenas métricas: bajo MB (−0,06 ± 0,08 m) y alto COE (0,58 ± 0,11). Las métricas en la costa norte fueron las más estables. El módulo de riesgo ha sido implementado en 79 playas. La erosión se ha estimado como un coste acotado, mientras que la inundación como un coste con alta cota superior. Las playas disipativas tienden a exhibir mayores costes que las playas reflejantes bajo altos niveles del mar. Episodios con Tr,waves _ 10yrs, concomitantes a mareas meteorológicas pueden conllevar costes significantes. Las pérdidas estimadas para N-15 (2510 · 103euros) no difieren en exceso de J-17 (3200 · 103 euros). Dos tipos de MAR han sido testeadas numéricamente: (i) dunas y (ii) diques exentos constituídos por geotextiles llenos de arena. Los beneficios de mantener estables los volúmenes de arena superan la reducción de los costes por inundación. En términos generales, los diques exentos pueden ser una opción adecuada para playas de estado morfodinámico intermedio frente a oleaje de alto período de retorno y niveles del mar bajos a moderados. En playas disipativas, las dunas son la mejor opción, pero requieren un ancho mínimo de playa (cerca de 30 m) que garantice su vida útil. La funcionalidad de las MAR puede mejorarse mediante acciones compatibles a largo-plazo (alimentaciones, bypass de arena, vegetación sumergida, etc.). Un estado de playa saludable es esencial para la efectividad de las MAR. Una gestión más sostenible bajo clima presente y futuro puede ser alcanzada mediante (i) CEWS como herramienta de predicción a corto plazo; (ii) MAR que mitiguen los impactos de los temporales y (iii) intervenciones a largo-plazo que mejoren la salud de la costa.

Les systèmes actuels de base de données géodécisionnels (GeoBI) ne tiennent généralement pas compte de l'incertitude liée à l'imprécision et le flou des objets; ils supposent que les objets ont une sémantique, une géométrie et une temporalité bien définies et précises. Un exemple de cela est la représentation des zones à risque par des polygones avec des limites bien définies. Ces polygones sont créés en utilisant des agrégations d'un ensemble d'unités spatiales définies sur soit des intérêts des organismes responsables ou les divisions de recensement national. Malgré la variation spatio-temporelle des multiples critères impliqués dans l’analyse du risque, chaque polygone a une valeur unique de risque attribué de façon homogène sur l'étendue du territoire. En réalité, la valeur du risque change progressivement d'un polygone à l'autre. Le passage d'une zone à l'autre n'est donc pas bien représenté avec les modèles d’objets bien définis (crisp). Cette thèse propose des concepts fondamentaux pour le développement d'une approche combinant le paradigme GeoBI et le concept flou de considérer la présence de l’incertitude spatiale dans la représentation des zones à risque. En fin de compte, nous supposons cela devrait améliorer l’analyse du risque. Pour ce faire, un cadre conceptuel est développé pour créer un model conceptuel d’une base de donnée multidimensionnelle avec une application pour l’analyse du risque d’érosion côtier. Ensuite, une approche de la représentation des risques fondée sur la logique floue est développée pour traiter l'incertitude spatiale inhérente liée à l'imprécision et le flou des objets. Pour cela, les fonctions d'appartenance floues sont définies en basant sur l’indice de vulnérabilité qui est un composant important du risque. Au lieu de déterminer les limites bien définies entre les zones à risque, l'approche proposée permet une transition en douceur d'une zone à une autre. Les valeurs d'appartenance de plusieurs indicateurs sont ensuite agrégées basées sur la formule des risques et les règles SI-ALORS de la logique floue pour représenter les zones à risque. Ensuite, les éléments clés d'un cube de données spatiales floues sont formalisés en combinant la théorie des ensembles flous et le paradigme de GeoBI. En plus, certains opérateurs d'agrégation spatiale floue sont présentés. En résumé, la principale contribution de cette thèse se réfère de la combinaison de la théorie des ensembles flous et le paradigme de GeoBI. Cela permet l’extraction de connaissances plus compréhensibles et appropriées avec le raisonnement humain à partir de données spatiales et non-spatiales. Pour ce faire, un cadre conceptuel a été proposé sur la base de paradigme GéoBI afin de développer un cube de données spatiale floue dans le system de Spatial Online Analytical Processing (SOLAP) pour évaluer le risque de l'érosion côtière. Cela nécessite d'abord d'élaborer un cadre pour concevoir le modèle conceptuel basé sur les paramètres de risque, d'autre part, de mettre en œuvre l’objet spatial flou dans une base de données spatiales multidimensionnelle, puis l'agrégation des objets spatiaux flous pour envisager à la représentation multi-échelle des zones à risque. Pour valider l'approche proposée, elle est appliquée à la région Perce (Est du Québec, Canada) comme une étude de cas.
Current Geospatial Business Intelligence (GeoBI) systems typically do not take into account the uncertainty related to vagueness and fuzziness of objects; they assume that the objects have well-defined and exact semantics, geometry, and temporality. Representation of fuzzy zones by polygons with well-defined boundaries is an example of such approximation. This thesis uses an application in Coastal Erosion Risk Analysis (CERA) to illustrate the problems. CERA polygons are created using aggregations of a set of spatial units defined by either the stakeholders’ interests or national census divisions. Despite spatiotemporal variation of the multiple criteria involved in estimating the extent of coastal erosion risk, each polygon typically has a unique value of risk attributed homogeneously across its spatial extent. In reality, risk value changes gradually within polygons and when going from one polygon to another. Therefore, the transition from one zone to another is not properly represented with crisp object models. The main objective of the present thesis is to develop a new approach combining GeoBI paradigm and fuzzy concept to consider the presence of the spatial uncertainty in the representation of risk zones. Ultimately, we assume this should improve coastal erosion risk assessment. To do so, a comprehensive GeoBI-based conceptual framework is developed with an application for Coastal Erosion Risk Assessment (CERA). Then, a fuzzy-based risk representation approach is developed to handle the inherent spatial uncertainty related to vagueness and fuzziness of objects. Fuzzy membership functions are defined by an expert-based vulnerability index. Instead of determining well-defined boundaries between risk zones, the proposed approach permits a smooth transition from one zone to another. The membership values of multiple indicators (e.g. slop and elevation of region under study, infrastructures, houses, hydrology network and so on) are then aggregated based on risk formula and Fuzzy IF-THEN rules to represent risk zones. Also, the key elements of a fuzzy spatial datacube are formally defined by combining fuzzy set theory and GeoBI paradigm. In this regard, some operators of fuzzy spatial aggregation are also formally defined. The main contribution of this study is combining fuzzy set theory and GeoBI. This makes spatial knowledge discovery more understandable with human reasoning and perception. Hence, an analytical conceptual framework was proposed based on GeoBI paradigm to develop a fuzzy spatial datacube within Spatial Online Analytical Processing (SOLAP) to assess coastal erosion risk. This necessitates developing a framework to design a conceptual model based on risk parameters, implementing fuzzy spatial objects in a spatial multi-dimensional database, and aggregating fuzzy spatial objects to deal with multi-scale representation of risk zones. To validate the proposed approach, it is applied to Perce region (Eastern Quebec, Canada) as a case study.

Egmont Key, located at the mouth of Tampa Bay, is part of a dynamic system with many interrelated natural and anthropogenic factors influencing its morphodynamics. This study started in August 2012. During the 3-year period until August 2015, 28 beach profile transects were established and surveyed 10 times. Seventeen historical aerial images from 1942 to 2013 were geo-rectified and analyzed. Three hundred and fourteen sediment samples were procured from the navigation channel dredge area and the beach nourishment area and analyzed for grain size. A numerical wave model was established to simulate the nearshore wave field. The overall goals of this study are to understand the complex morphodynamics of Egmont Key and to evaluate the shore-protection efforts. The overall area of the Egmont Key has reduced 52% from 2.1 km2 in 1942 to 1.o km2 in 2002. The area loss was mostly caused by beach erosion along the Gulf-facing beach. The island-area reduction from 1942 to 2002 was largely linear. Two periods of accelerated area loss from 1978-1984 and 1999-2002 can be related to dredging of the Egmont Channel and the disposal of dredged materials along the channel. Concerning the relatively high mud content in the borrow area for the 2014 nourishment, a large amount of the fine sediment was lost at a temporal scale of hours to days during the dredging and beach nourishment construction processes. Some of the mud was deposited outside the surf zone at water depths of 2 m or greater. This mud became eroded naturally by energetic conditions at a temporal scale of months. Beach erosion and accretion along the Gulf-facing beach can be related qualitatively to tidal flow patterns. Numerical wave modeling shows that the transverse bars offshore Egmont Key have a moderate influence on the wave field, leading to slightly different wave heights along the shoreline. However, there is no clear relationship between the nearshore wave conditions and the erosion/accretion patterns. The severe shoreline erosion has exposed various fort structures at the shoreline and in the nearshore zone. These structures function as detached breakwaters or groins and have localized influence on the beach state.

Shippagan Gully is a tidal inlet located near Shippagan, New Brunswick on the Gulf of Saint Lawrence. It is a particularly complex tidal inlet due to the fact that its tidal lagoon transects the Acadian peninsula and is open to the Bay des Chaleurs at its opposite end. As such, two open boundaries with phase lagged tidal cycles drive flow through the inlet, alternating direction with each tide and reaching velocities in excess of 2m/s. Hydrodynamic and morphological processes at the site are further complicated by the presence of a highly variable wave climate. Presently, shipping practices through the inlet are limited due to continual sedimentation within and immediately offshore from Shippagan Gully. As such, an extensive field study, desktop analysis and numerical and morphological modeling of Shippagan Gully have been conducted in order to provide guidance for future works. Modeling was conducted using the CMS-Wave and CMS-Flow numerical modeling system.

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O litoral central do estado de Pernambuco concentra grande parte da população do Estado, além de apresentar grande atrativo comercial e turístico. Paralelamente, a região sofre com o processo erosivo tanto estrutural (de médio e longo-termo) quanto episódico (de curto-termo), o que acarreta danos e prejuízos em termos ambientais e socioeconômicos. Neste contexto, o presente estudo foi desenvolvido no intuito de abordar a problemática da erosão costeira nos municípios de Paulista, Olinda, Recife e Jaboatão dos Guararapes, com especial atenção àquela associada à escala temporal de horas a dias, além de discutir suas causas. Adicionalmente, foi contemplado neste estudo o conceito do risco e a sua aplicação no domínio do gerenciamento costeiro. Para tanto, o estudo foi dividido em quatro capítulos centrais (Capítulos 2, 3, 4 e 5), em consonância com os seus objetivos específicos. O primeiro deles (Capítulo 2), teórico, foi dedicado à elaboração do estado-da-arte dos estudos que abordam o tema “risco” aplicado à erosão costeira nas escalas local, regional e global. Entre os resultados, observou-se que tais estudos tem se avolumado ao longo do tempo e que ainda existem indefinições no que se refere ao conceito do risco, o qual nem sempre é aplicado segundo a métrica da equação que o descreve, na qual o risco é o produto entre a incerteza associada a um evento e suas consequências. O segundo (Capítulo 3) objetivou caracterizar o processo erosivo em curso na área de estudo e sua elaboração indicou que, embora as praias nos municípios contemplados sofram frequentemente com a erosão, o mesmo não necessariamente está relacionado à retração da linha de costa. Muitas vezes, tal processo é produto da ocupação inadequada dos setores da praia, a qual não permite que o sistema se ajuste diante de qualquer oscilação nas condições hidrodinâmicas. O terceiro capítulo central da tese (Capítulo 4) trata das forçantes associadas aos eventos de alta energia, os quais promovem episódios erosivos de curto-termo na região. Corroborando estudos anteriores, os resultados apontam para a contribuição do vento, em especial da intensificação da sua componente sul, bem como da maré, na ocorrência de tais eventos. As ondas, embora contribuam, apresentam menor importância. Finalmente, o Capítulo 5 apresenta uma análise de risco à erosão episódica simples e semi-quantitativa para duas praias do litoral de Paulista, município identificado como área crítica no que se refere à erosão. A abordagem metodológica procurou ser fiel à equação que descreve o risco e fez uso de dados pretéritos e de ferramentas computacionais acessíveis. Os resultados demonstraram que, mesmo diante de cenários frequentes, as praias não apresentam a resiliência necessária para se ajustar às oscilações energéticas impostas por ondas e níveis de água, sofrendo alterações consideráveis, em especial nas áreas mais ocupadas. Como considerações finais, pode-se dizer que o conceito do risco tem amplo potencial de aplicação ao gerenciamento costeiro, em especial no que se refere ao manejo da erosão costeira e, finalmente, que a manutenção da resiliência costeira é fundamental para a redução de riscos associados a este processo por meio da atenuação das suas consequências.
The central coast of Pernambuco State concentrates much of the state's population, and present great commercial and tourist attraction. At the same time, the region suffers with coastal erosion in both time scales, structural (medium and long-term) and episodic (short-term), which causes damages in environmental and socioeconomic aspects. In this context, the present study was developed in order to aim the problem of coastal erosion in the cities of Paulista, Olinda, Recife and Jaboatão dos Guararapes, with special attention to that associated with the time scale of hours to days, besides discussing its causes. Additionally, it was considered in this study the concept of risk and its application in the field of coastal management. Therefore, the study was divided into four main chapters (Chapters 2, 3, 4 and 5), in consonance with their specific goals. The first of them (Chapter 2), theoretic, was dedicated to the development of state-of-art of studies addressing the topic "risk" applied to coastal erosion in local, regional and global scales. Among the results, it was observed that such studies has been increasing over time and that there are indeterminations as regards the risk concept, which is not always applied according to the metric of equation that describes it, in which risk is the product of the uncertainty associated with an event and its consequences. The second (Chapter 3) aimed to characterize the erosion process in progress in the study area and its development indicated that although the beaches in the covered municipalities often suffer from erosion, it is not necessarily related to the shoreline retreat. Often, such a process is a product of inadequate occupation of the beach areas, which does not allow the system to fit on any fluctuation in hydrodynamic conditions. The third central chapter of the thesis (Chapter 4) deals with the forcings associated with high-energy events, which promote erosion episodes of short-term in the region. Corroborating previous studies, the results point to the wind contribution, particularly to the intensification of its southern component as well as the tide, as most responsible for the occurrence of such events. The waves, although contributing, present lower importance. Finally, Chapter 5 presents a risk analysis to short-term erosion that was conducted by a simple and semi-quantitative method and applied to two beaches located in Paulista, municipality identified as a critical area with regard to erosion. The methodological approach sought to be faithful to the equation that describes the risk and uses past data and accessible computational tools. The results showed that, even face to frequent scenarios, the beaches do not present the resilience necessary to adjust its shape to the energy oscillations caused by waves and water levels, undergoing considerable changes, especially in the urban areas. As final considerations, it can be said that the risk concept has broad potential application to coastal management, especially with regard to the management of coastal erosion and finally that the maintenance of coastal resilience is key to reducing risk associated with this process through the mitigation of their consequences.

The increase in frequency and intensity of extreme coastal storms and the continuous exponential development of the coasts of the world are threatening coastal communities, exposing them to higher levels of risk. Notwithstanding the future projections are affected by large uncertainty, coastal managers, as recommended by the United Nations and the European Union, need to properly evaluate coastal risk in order to propose adequate risk reduction plans for the current and future climate change scenarios. This should be done while considering all the components that influence risk: hazard, vulnerability and exposure. The involvement of local stakeholders and the adoption of multi-disciplinary approaches, including social sciences, are becoming very common in coastal risk studies, supporting the idea that the same should be done at the management level, to properly address coastal risk issues. The work of this PhD thesis aimed at applying innovative approaches for the evaluation of coastal risk, at different scales, on Mediterranean sandy beaches. The innovations are related to fieldwork methodologies, numerical applications and coastal risk assessment. Part of the work was done in the framework of the EU FP7 RISC-KIT project, that aimed at providing tools in support of coastal managers, in order to increase the resilience of coastal communities. The approaches were implemented at locations along the Emilia-Romagna (Italy) and Catalunya (Spain) coasts. The first part of this thesis focuses on fieldwork activities. Post-storm and seasonal surveys were implemented based on up-to-date low-cost drones and photogrammetric techniques for post-processing. The approach allowed to collect local-scale high-resolution data used to integrate regional post-storm assessments, including qualitative information collected involving the local community, and to detect significant changes of the beach due to the influence of coastal storms and winds. Numerical models were used to analyze the propagation of errors due to the use of synthetic time-series of waves in a process-based chain of models used to simulate erosion and flooding hazards. Results were analyzed with a Bayesian-based approach. The use of synthetic time-series can produce significant errors in the hazard assessment, if compared with the use of real ones, and can influence the risk assessment. Then, two coastal risk assessments are presented, respectively at the local and regional levels. The studies were implemented using the RISC-KIT tools: the Coastal Risk Assessment Framework (CRAF) Phase 1 for the identification of critical areas (hotspots) at the regional level and the Bayesian-based Hotspot tool for testing local measures for disaster reduction, in the current and future scenarios. The CRAF Phase 1 was validated on the Emilia-Romagna coast, confirming that it is able to detect well-known hotspots. The Hotspot tool provided useful insights on the tested measures at the two analyzed case study sites, in Italy and Spain. The applications confirmed that the RISC-KIT approach for regional and local scale assessments is valuable for coastal managers, in order to propose adequate solutions for risk reduction. An interesting aspect of this PhD work is that the majority of the applications were implemented including local people and managers in the process. Large parts of the integrated risk assessments were supported by a strong collaboration between physical and social scientists, confirming that a multi-disciplinary approach is a key aspect in order to properly understand and reduce coastal risk. Coastal managers should take into account all the aspects analyzed in this PhD thesis that can affect risk assessments, from the fieldwork to the deskwork. They should be able to properly address risk by interacting with physical and social scientists, as well as with local communities, if they want to provide effective and acceptable risk reduction strategies.
Le coste del mondo sono minacciate dall'incremento, in frequenza ed intensità, delle mareggiate e dello sviluppo costiero. Pertanto, le comunità costiere sono esposte a livelli di rischio sempre più elevati. Le Nazioni Unite e l'Unione Europea richiedono ai manager costieri di valutare il rischio delle coste per proporre piani di riduzione adeguati, sia per lo scenario attuale, sia per quello futuro, considerando i possibili effetti del cambiamento climatico, sebbene le proiezioni future siano caratterizzate da incertezze non trascurabili. Le valutazioni di rischio devono essere basate considerando pericolosità, vulnerabilità ed esposizione. Dovrebbero essere svolte adottando approcci multi-disciplinari e coinvolgendo i portatori di interesse. Il lavoro oggetto di questa tesi è stato svolto applicando approcci innovativi per la valutazione del rischio su spiagge sabbiose del Mediterraneo, a diverse scale spaziali. Le applicazioni riguardano diversi campi: rilievi di spiaggia, modellazione numerica e valutazione integrata del rischio. Parte del lavoro è stato svolto nell'ambito del progetto EU FP7 RISC-KIT, il cui obiettivo era fornire ai manager costieri strumenti utili alla riduzione del rischio ed all'incremento della resilienza delle comunità costiere. Gli approcci sono stati applicati in località costiere in Emilia-Romagna (Italia) e Catalogna (Spagna). La prima parte di questa tesi riguarda aspetti di misure sul campo. Sono stati utilizzati droni a basso costo e tecniche di fotogrammetria per rilievi post-evento e stagionali. Sono stati raccolti a scala locale dati ad alta risoluzione utili sia ad integrare rilievi post-evento a scala regionale, includendo informazioni qualitative ottenute coinvolgendo la comunità locale, sia all'analisi delle variazioni della spiaggia dovute alle mareggiate e ai venti. Sono stati utilizzati modelli numerici per analizzare, tramite approccio Bayesiano, la propagazione degli errori dovuti all'utilizzo di mareggiate sintetiche in input ad una catena di modelli per la simulazione dell'erosione ed inondazione costiera. L'uso di input sintetici produce errori significativi nella valutazione dei pericoli, se confrontato con l'uso di serie temporali reali, e può avere effetti importanti sulle successive analisi del rischio. Inoltre, si presentano due valutazioni di rischio, a scala regionale e locale. Sono stati applicati gli strumenti forniti da RISC-KIT, il Coastal Risk Assessment Framework (CRAF) Phase 1 per l'identificazione delle aree critiche (hotspot) a livello regionale e l'Hotspot tool, un approccio Bayesiano per l'analisi dell'efficacia di misure di riduzione del rischio, per gli scenari attuali e futuri. Il CRAF Phase 1 è stato validato per la costa dell'Emilia-Romagna dimostrandosi efficace nell'identificare aree critiche note. L'Hotspot tool ha fornito informazioni utili alla caratterizzazione delle misure in entrambi i casi studio, in Italia e Spagna. Le analisi hanno dimostrato che l'approccio di RISC-KIT è utile ai manager costieri per la preparazione di piani adeguati di riduzione del rischio. Un aspetto interessante di questo lavoro riguarda il coinvolgimento dei portatori di interesse e dei manager costieri nella maggior parte delle analisi svolte. La collaborazione tra studiosi delle scienze naturali e sociali è stata di estrema importanza per l'appropriata valutazione del rischio costiero a diverse scale spaziali. Questo conferma che l'approccio multi-disciplinare è un aspetto chiave per comprendere e ridurre il rischio costiero. I manager costieri dovrebbero tenere in considerazione tutti gli aspetti che influenzano le valutazioni di rischio presentati in questa tesi, dalle misure sul campo al lavoro alla scrivania. Dovrebbero interagire maggiormente con i ricercatori che studiano le coste, sia dal punto di vista fisico sia sociale, e con i portatori di interesse, per fornire strategie per la riduzione del rischio che siano efficaci e condivisibili.

Nowadays, one of the urgent issues in the management of river basin resources as land degradation, especially soil erosion risk occurs due to complex factors of climate, cultivation practices of human and impacting of the operation of socio-economic development taking place in the basin. Soil erosion has been considered as the primary cause of soil degradation since soil erosion leads to the loss of topsoil and soil organic matters, which are essential for the growing of plants. Ta Trach river watershed, is a mountainous basin lying to the West - South of Thua Thien Hue province, having complex terrain. The result of this study showed that the amount of sediment yield accounts for high percentage. The average annual sedimentation is 41.60 tones per hectometer in the period of 2005 to 2010, soil erosion were classified by 5 levels. In which, the less deleterious erosion level still occupies high percentage with more than 55 % of watershed area. The main area of less deleterious soil erosion was located at high topography and high slope. The area of deleterious soil erosion occupies percentage lower than 22.63% of the entire basin, but it is also a warning sign to the extent of land degradation taking place in the basin if the erosion rate increases in the future
Ngày nay, một trong những vấn đề cấp bách trong quản lý tài nguyên lưu vực sông là sự thoái hóa đất và đặc biệt là nguy cơ xói mòn đất xảy ra do yếu tố khí hậu phức tạp, phương thức canh tác của con người và tác động của những hoạt động phát triển kinh tế - xã hội đang diễn ra ở lưu vực. Lưu vực sông Tả Trạch là một lưu vực miền núi nằm về phía Tây - Nam của tỉnh Thừa Thiên Huế, có địa hình khá phức tạp. Mục tiêu của nghiên cứu này là ứng dụng công cụ SWAT để mô phỏng xói mòn đất ở lưu vực sông Tả Trạch thuộc tỉnh Thừa Thiên Huế từ năm 2005 đến năm 2010. Kết quả của nghiên cứu cho thấy lượng đất bồi lắng ở lưu vực chiếm tỷ lệ cao, trung bình mỗi năm bồi lắng 41.60 tấn/ha trong giai đoạn 2005 đến 2010, mức độ xói mòn được phân cấp thành 5 cấp xói mòn. Trong đó, mức độ xói mòn ít nguy hại chiếm ở tỷ lệ cao hơn 55 % diện tích lưu vực, chủ yếu phân bố ở những khu vực có địa hình cao, độ dốc lớn. Diện tích xói mòn nguy hại chiếm tỷ lệ thấp hơn 22,63% diện tích toàn lưu vực nhưng đây cũng là một dấu hiệu báo động cho mức độ thoái hóa đất diễn ra ở lưu vực trong tương lai nếu mức xói mòn này tăng lên

Coastal urban settlements require a special planning approach since they bring the concepts of &ldquo
urban&rdquo
and &ldquo
coastal&rdquo
together. In relation to the specific contents of these concepts, there are also different models of management plans. &ldquo
Urban Disaster Risk Management&rdquo
and &ldquo
Integrated Coastal Zone Management&rdquo
are two of them. Urban Disaster Risk Management model deals with the planning and management problems of urban settlements in the case of disaster risk conditions. Likewise, Integrated Coastal Zone Management model focuses on the whole coastal area and deals with the sustainable use and protection of all types of coastal resources. However, in case of urban coastal settlements, these models of management plans can be valid together, can overlap, and they can even conflict with each other. In this thesis study, these two models of management plan and their coexistence are considered. A Coastal Area Assessment Model is set up and applied for Iskenderun case. This model provides a detailed spatial analysis opportunity in planning and management of coastal urban settlement. Therefore the model offers a significant input for the planning process through determining urban and coastal risks at the same time. Coastal Area Assessment Model is a tool which takes both Urban Disaster Risk Management and Integrated Coastal Zone Management models&rsquo
concerns into account and evaluates the coastal settlement in terms of urban risk sectors and coastal management issues. This study also introduces an approach on classification of the coastal areas and coastal urban settlements while setting up the Coastal Area Assessment Model. Coastal Area Assessment Model becomes an advantageous tool since it has significant contributions to the planning process by making a simple risk analysis and guiding the proper utilization and protection of the population, built environment, and resources of the coastal areas. Risk sectors, coastal management issues, critical and prior intervention areas of a coastal urban settlement are easily determined, and preparation of development plans of a coastal settlement is guided by the implementation of Coastal Area Assessment Model. In addition to these, general principles on planning and management of coastal settlements are determined by the implementation of the model for the implementation conditions of Urban Disaster Risk Management model, Integrated Coastal Zone Management model, and the Coastal Area Assessment Model in Turkey are also discussed and presented.

Na atual discussão do processo de mudanças climáticas, e seus efeitos nas zonas costeiras, o presente estudo tem como objetivo ampliar o entendimento dos fatores responsáveis pelo processo erosivo estabelecido na praia do Hermenegildo, entre os anos de 1947 e 2012, através da associação de dados oceanográficos que levam a intensificação desse processo, e dados geomorfológicos tradicionais. A partir de dados de linha de costa, obtidos através de imagens de satélite, fotografias aéreas, de diferentes épocas, e dados de GPS RTK coletados in situ, foi possível caracterizar o comportamento da linha de costa da praia do Hermenegildo em micro e mesoescala. Dados de TSM, direção e intensidade dos ventos e altura de ondas, obtidos da NOAA, também foram incorporados no estudo. Ao longo de 65 anos, a taxa de retração média da linha de costa foi de 1,68 m/ano, com os maiores picos erosivos registrados entre os anos de 1996 a 2000 (6,29 m/ano) e 2005 a 2006 (5,25 m/ano). Os intervalos com as maiores taxas de recuo são coincidentes com os períodos de ocorrência de forte El Niño e anomalias na TSM. Em anos onde esses eventos são coincidentes, em mesma intensidade, foram registradas as maiores perdas por erosão. Um comparativo feito entre os dados de TSM e retração média da linha de costa apresentaram uma correlação de 80%, num cenário onde os ventos provenientes do quadrante SW são os mais significativos. Quando comparados os dados de TSM e nível médio do mar local (obtidos por modelagem), esses não apresentam correlação significativa. Contudo, quando analisados e comparados separadamente, os dados variam coincidentemente para o mesmo intervalo temporal de forma que, quando se identificou variações na TSM, observou-se também uma variação no nível. O conhecimento do comportamento da linha de costa é fundamental para fins de planejamento e ordenamento do litoral. Dessa forma, a partir do conjunto de dados, foi efetuada uma previsão da posição futura da linha de costa para os anos de 2022, 2032 e 2100, tendo como base o ano de 2012. Estas apresentaram um recuo de 8,18 m, 22,29 m e 151,57 m, respectivamente. De posse dessas informações, um mapa de probabilidades ao processo erosivo foi gerado destacando que, o setor norte do balneário é o mais suscetível à erosão. O produto cartográfico obtido, o qual contempla informações de diferentes escalas, poderá servir como uma ferramenta importante aos gestores costeiros municipais. No que diz respeito ao estabelecimento de possíveis soluções para amenizar ou mitigar a problemática da erosão, o mapa de probabilidades à erosão dará suporte ao processo de expansão do balneário, à medida que os gestores terão mapeadas as áreas de maior e menor probabilidade ao processo erosivo.
In the context of the current discussion of climate change and its effects along the coast al zones, this study aims to broaden the understanding about the responsible factors for the well established coastal erosion at Hermenegildo beach, between the years 1947 and 2012, throughout the association of oceanographic data that may have lead to its intensification, and conventional geomorphological data. Using shoreline position data, through satellite imagery, air photographs of various periods combined with GPS RTK data collected in situ, it was possible to characterize shoreline behavior at micro and medium scale. TSM, wind strength and direction as well as wave height data from NOAA, have also been incorporated to this study. Along 65 years, mean shoreline recession has been of 1.68 m/yr, with highest erosion rates registered between 1996 and 2000 (6.29 m/yr) and between 2005 and 2006 (5.25 m/yr). The highest shoreline recession values coincide with El Niño periods and with TSM anomalies. Throughout the years when these events coincided and had the same intensity, the highest erosion rates were registered. A comparison between TSM data and mean shoreline recession demonstrated a positive correlation of 80%, in a scenario where SW winds predominate. Conversely, when TSM and mean local sea level (modeled), no significant correlation was observed. Nonetheless, when compared and analyzed separately, data varied coincidently for the same time interval, that is when variations in TSM occurred, mean sea level also varied. Understanding shoreline behavior is essential for coastal planning and development. This way, using the available data it was possible to predict future shoreline position for the years 2022, 2032 and 2100, using the 2012 shoreline position as a starting point. Resulting future shoreline positions are 8.18 m, 22.29 m and 151.57 m, respectively. Based on this information, a probabilistic map of erosion risk was prepared highlighting that the northern sector of Hermenegildo is more susceptible to erosion. The resulting cartographic product, which comprises information at various scales, may be used as an important tool for local coastal managers. Regarding the establishment of possible solutions in order to mitigate the erosion problem, the erosion probability map will give support to broaden urbanization along the beach, since the coastal managers will know which area are at higher or lower risk of erosion.

This research explored community coastal values and how they may be impacted as a result of climate change, explicitly coastal erosion and inundation. The research also examined how specific collaborative learning practices can enhance understanding and knowledge uptake of coastal climate change in the community and how community values of the coast can be incorporated into coastal hazard risk management and adaptation planning.

Local communities must have a capacity to ameliorate coastal erosion impacts. Since coastal erosion operates over long time frames, understanding this capacity, or the abilities of communities to respond to the impacts and recover to maintain community functions, requires analysis of the past and the present. This study explores factors which influence the capacity of communities to respond to coastal erosion and conversely how exposure to coastal erosion itself affects community capacity. Mixed methods research was used to investigate the views of respondents in seven coastal villages in the upper Gulf of Thailand, three from an area that has experienced low erosion, and four from an area that has experienced high erosion. A questionnaire survey was administered 358 respondents to investigate socio-demographic characteristics, opinions about livelihoods in communities and experiences of losing and responding to coastal erosion. Thirty five key informants for semi-structured interviews were selected from villagers who responded to the questionnaire and volunteered as well as officials, scientists and NGOs. Descriptive analyses were applied to examine differences in socio-demography, opinion about livelihood and coastal erosion experience variables between the two areas, and factor analysis was used to investigate the importance of factors that affect and could build community capacity to respond to coastal erosion. The physical characteristics of the high erosion area were significantly different to those of the low erosion area. The former was closer to the Chao Praya Delta River, had many shrimp ponds across villages and residents applied materials which were too fragile to prevent coastal erosion. The low erosion area was far from delta rivers, was surrounded by shrimp ponds and hard structures were applied to protect the coastal area. For socio-demographic characteristics of villagers, residents in the high erosion area had less employment, lower education, lower income and lower levels of land ownership than residents in the low erosion area. Residents in the high erosion area reported more experiences of property loss from coastal erosion in the past 30 years than residents in the low erosion area as would be expected. Across the two erosion areas rock placements were applied as a common method to protect the coast in the past, while embedding thin bamboo stems offshore was also used in the high erosion area. The government and other networks had promoted a combination of methods to protect coastal areas by embedding thick bamboo stems offshore and planting mangrove trees in intertidal areas. This combination of methods was yielding positive results. Residents impacted by coastal erosion migrated landwards from eroded area and those residents lost connection with their neighbours, lacked opportunities for generating their own income or obtaining employment, and spent their savings in mobilising and rebuilding houses. Some residents who felt insecure from erosion sold their land to external landholders and then they moved to live in more secure areas away from their villages, taking their financial resources with them, thereby effectively removing their financial resources from the original communities. The external landholders held increasingly large areas in these villages. Local communities thereby suffered from a lack of finance and power and diminished rights to build infrastructure for coastal erosion prevention and improvement of their quality of life. Five main factors were found from multivariate factor analysis. Firstly, villagers having control over their own land (and therefore control over their destiny) provided more opportunities to build structures to prevent coastal erosion in their own communities. Secondly, higher levels of leadership were central to mobilising resources to address coastal erosion problems provided the leaders had the necessary attributes to deal with this challenge. Thirdly, coastal community resilience was necessary for communities to address existing changes, whereas communities needed to maintain their functions to be ready to respond to unpredictable impacts of coastal erosion and other events without diminishing their potential. Fourthly, enhanced levels of sense of community were important to gain collaboration from residents to cope with coastal erosion. Lastly, a positive household socioeconomic element was necessary for residents to have sufficient resources for building natural hazard protection appropriately. These five issues could be highlighted to coastal communities to improving capacities to respond to coastal erosion effectively, whereas local authorities and other organisations with high capability could facilitate and support the communities to build capacities through those issues.

Forestry best management practices (BMPs) programs were developed by individual states in response to the Clean Water Act in order to protect water quality during and after timber harvests. Our research goals are to compare BMP implementation at stream crossings by region and road type in Virginia and to quantify effectiveness of BMPs by developing hypothetical upgrades and determining upgrade costs. Stream crossings (75 truck, 79 skidder) sampled for BMP implementation were on operational harvests conducted in 2016, from the Mountains, Piedmont, and Coastal Plain of Virginia. Erosion rates of stream crossing approaches were modeled using the Universal Soil Loss Equation modified for forest lands (USLE-Forest) and Water Erosion Prediction Project (WEPP) methodologies. Implementation ratings (BMP-, BMP-standard, BMP+) were developed to characterize crossings with respect to state implementation standards. Costs for upgrading crossings to a higher BMP category were estimated by adjusting cover percentages and approach lengths. Sixty-three percent of stream crossings were classified as BMP-standard, with an average erosion rate of 7.6 Mg/ha/yr; 25% of crossings were classified as BMP+, with an average erosion rate of 1.7 Mg/ha/yr; and 12% of crossings were classified as BMP-, with an average erosion rate of 26.2 Mg/ha/yr. Potential erosion rates decreased with increasing BMP implementation (p <0.0001). Average BMP implementation audit scores for stream crossings were 88% on skid trails and 82% on truck roads. To upgrade from a BMP- to BMP-standard, the cost-benefit ratio of dollars to tons of sediment prevented averaged $166.62/Mg for skid trails and $2274.22/Mg for truck roads. Enhancement to the BMP+ level is not economically efficient and BMP implementation at stream crossings reaches maximum efficiency at the BMP-standard level.
M. S.

[ES] Las playas son espacios costeros que desarrollan numerosas funciones ambientales. Éstas proporcionan importantes beneficios a la sociedad y a las comunidades costeras, entre las que destacan la función ecológica, el suministro de protección para los territorios costeros y el hecho de que constituyen un recurso básico de la industria turística. De forma ligada al cambio climático, así como a acciones humanas que alteran el dinamismo natural de la costa, las playas están experimentando procesos erosivos cada vez más dañinos que afectan a su integridad física y al mantenimiento de sus funciones. La gestión de las playas en muchas ocasiones no se encuentra adaptada a las particularidades de los diferentes segmentos costeros. La toma de decisiones no se sustenta en información suficiente sobre las características, el dinamismo y el estado actual de las playas, dando lugar a soluciones cortoplacistas o ineficaces. Las características geomorfológicas son esenciales en el desarrollo de sus funciones al condicionar sus dimensiones físicas y su comportamiento frente a la acción del mar. Por ello, su caracterización de forma detallada y actualizada es necesaria para llevar a cabo acciones eficientes, permitiendo virar hacia una gestión costera más ecosistémica y sostenible. Las técnicas de teledetección presentan una gran capacidad para la adquisición de datos de la superficie terrestre. En concreto, los satélites Sentinel-2 y Landsat (5, 7 y 8) permiten disponer de forma gratuita imágenes de resolución media con cobertura mundial y alta frecuencia de revisitado. Los algoritmos de extracción de la línea de costa desarrollados recientemente por el Grupo de Cartografia GeoAmbiental y Teledetección (CGAT - UPV) permiten definir sobre estas imágenes la posición de la línea de costa, constituyendo datos potencialmente útiles para describir la morfología de las playas y su dinamismo. Universalizar su aplicación requiere su testeo y validación en diferentes tipos de costa. Para ello, el proceso de extracción ha sido adaptado para su explotación en entornos mareales, y las líneas de costa resultantes han sido evaluadas ante diferentes condiciones oceanográficas ofreciendo una precisión cercana a los 5 m RECM (raíz del error cuadrático medio). Teniendo en cuenta las necesidades de información para la gestión existentes, a partir de estas líneas de costa se propone derivar indicadores que permitan caracterizar la geomorfología de las playas y monitorizar sus cambios. Para ello, las metodologías propuestas aseguran una gestión eficiente de grandes volúmenes de líneas de costa, siendo así capaces de caracterizar las playas cubriendo grandes territorios y periodos de tiempo. Así se derivan el ancho de playa y el tamaño de los granos de sedimento como indicadores objetivos y fácilmente comprensibles de la geomorfología de la playa. La modelización espacio-temporal del estado y los cambios de la línea de costa y de la anchura posibilita monitorizar la respuesta de las playas a temporales y a actuaciones antrópicas, permitiendo analizar los cambios ocurridos cada pocos días hasta cubrir décadas. Su cobertura espacial junto a la integración con otras bases de datos cartográficas permite caracterizar la influencia de la geomorfología de la playa en el desempeño de sus funciones, permitiendo un análisis holístico de la costa a escala regional. Las metodologías desarrolladas en esta tesis y los indicadores derivados desde la teledetección brindan apoyo para dotar de criterios y priorizar las acciones de los gestores. Se contribuye así a llenar el espacio existente entre la disponibilidad de técnicas para obtener información remota y su aplicación en los procesos de toma de decisiones sobre la costa.
[CAT] Les platges són espais costaners que desenvolupen nombroses funcions ambientals. Aquestes proporcionen importants beneficis a la societat i comunitats costaneres, entre les quals destaquen la funció ecològica, el subministrament de protecció per als territoris costaners i el fet que constitueixen un recurs bàsic de la indústria turística. De forma lligada al canvi climàtic, així com a accions humanes que alteren el dinamisme natural de la costa, les platges estan experimentant processos erosius cada vegada més nocius que afecten la seua integritat física i al manteniment de les seues funcions. La gestió de les platges en moltes ocasions no es troba adaptada a les particularitats dels diferents segments costaners. La presa de decisions no es sustenta en informació suficient sobre les característiques, el dinamisme i l'estat actual de les platges, donant lloc a solucions curtterministes o ineficaces. Les característiques geomorfològiques són essencials en el desenvolupament de les seues funcions en condicionar les seues dimensions físiques i el seu comportament enfront de l'acció de la mar. Per això, la seua caracterització de manera detallada i actualitzada és necessària per a dur a terme accions eficients, permetent virar cap a una gestió costanera més ecosistèmica i sostenible. Les tècniques de teledetecció presenten una gran capacitat per a l'adquisició de dades de la superfície terrestre. En concret, els satèl·lits Sentinel-2 i Landsat (5, 7 i 8) permeten disposar de manera gratuïta d'imatges de resolució mitjana amb cobertura mundial i alta freqüència de captura d'informació a un mateix punt. Els algorismes d'extracció de la línia de costa desenvolupats recentment pel Grup de Cartografia Geo-Ambiental i Teledetecció (CGAT - UPV) permeten definir sobre aquestes imatges la posició de la línia de costa, constituint dades potencialment útils per descriure la morfologia de les platges i el seu dinamisme. Universalitzar la seua aplicació requereix el seu testatge i validació en diferents tipus de costa. Per a això, el procés d'extracció ha sigut adaptat per a la seua explotació en entorns mareals, i les línies de costa resultants han sigut avaluades davant diferents condicions oceanogràfiques oferint una precisió pròxima als 5 m RMSE (arrel de l'error quadràtic mitjà). Tenint en compte les necessitats d'informació per a la gestió existents, a partir d'aquestes línies de costa es proposa derivar indicadors que permeten caracteritzar la geomorfologia de les platges i monitorar els seus canvis. Per a això, les metodologies proposades asseguren una gestió eficient de grans volums de línies de costa, sent així capaces de caracteritzar les platges cobrint grans territoris i períodes de temps. Així es deriven l'ample de platja i la grandària dels grans de sediment com a indicadors objectius i fàcilment comprensibles de la geomorfologia de la platja. La modelització espai-temporal de l'estat i els canvis de la línia de costa i de l'amplària possibilita monitorar la resposta de les platges a temporals i a actuacions antròpiques, permetent analitzar els canvis ocorreguts cada pocs dies fins a cobrir dècades. La seua cobertura espacial al costat de la integració amb altres bases de dades cartogràfiques permet caracteritzar la influència de la geomorfologia de la platja en l'acompliment de les seues funcions, permetent una anàlisi holística de la costa a escala regional. Les metodologies desenvolupades en aquesta tesi i els indicadors derivats des de la teledetecció brinden suport per a dotar de criteris i prioritzar les accions dels gestors. Es contribueix així a omplir l'espai existent entre la disponibilitat de tècniques per a obtenir informació remota i la seua aplicació en els processos de presa de decisions sobre la costa.
[EN] Beaches are coastal spaces that perform numerous environmental functions. They provide important benefits to society and coastal communities, including the ecological function, the provision of protection for coastal territories, and constitute a basic resource for the tourism industry. Due to climate change and human actions that alter the natural dynamism of the coast, beaches are experiencing increasingly harmful erosive processes that affect their physical integrity and the maintenance of their ecological functions. Beach management is often not adapted to the particularities of the different coastal segments. Decision-making is not based on sufficient information about characteristics, dynamism, and current state of beaches, resulting in short or ineffective solutions. Geomorphological characteristics are essential in the development of beach functions as they condition their physical dimensions and their behavior in response to the action of the sea. Therefore, their detailed and updated characterization is necessary to carry out efficient actions, allowing a more ecosystemic and sustainable coastal management. Remote sensing techniques have a great capacity for acquiring data from the land surface. In particular, Sentinel-2 and Landsat (5, 7, and 8) satellites freely provide medium resolution images with global coverage and high-revisit frequency. The algorithms for extracting the water/land interface recently developed by the Geo-Environmental Cartography and Remote Sensing Group (CGAT - UPV) allow defining the position of the shoreline on these images, constituting potentially useful data to describe beach morphology and dynamics. Universalizing their application requires testing and validation at different coastal types. For this purpose, the extraction process has been adapted for exploitation in tidal environments, and the resulting shorelines have been assessed under different oceanographic conditions offering an accuracy close to 5 m RMSE (Root-Mean-Square Error). From these shorelines, and taking into account the existing information needs for management, it is proposed to derive indicators to characterize the geomorphology of the beaches and to monitor their changes. To this end, the proposed methodologies ensure the efficient management of large volumes of shorelines, being able to characterize the beaches along broad coastal segments and periods. Thus, beach width and sediment grain size are derived as objective and easily understandable indicators of the beach geomorphology. Spatial-temporal modeling of the state and changes of shoreline position and beach width makes it possible to monitor the response to storms and anthropogenic actions, allowing to analyze changes that occur every few days or over decades. The large spatial coverage together with the integration with other cartographic databases allows characterizing the influence of beach geomorphology in the performance of its functions, offering a holistic view of the coast from a regional scale. The methodologies developed in this thesis and the indicators derived from remote sensing provide support and criteria for prioritizing the actions of managers. This contributes to fill the gap between the availability of techniques to obtain remote information and its application in the coastal decision-making process.
This research integrates findings and results obtained within the framework of the contract FPU15/04501 granted to the author by the Spanish Ministry of Education, Culture, and Sports, which has allowed this doctoral thesis to become a reality. The research has been supported by the funds of the project RESETOCOAST, by the Ministry of Economy, Industry, and Competitiveness (chapters 2 to 5), and the project MONOBESAT PID2019-111435RB-I00 by the Ministry of Science, Innovation, and Universities (chapter 6). About my stay in Portugal, it was possible with the funds of the Erasmus+ program. The contribution of Ó. Ferreira was funded by EW-COAST (PTDC/CTA-OHR/28657/2017) and by FCT and Univ. Algarve through the grant UID/MAR/00350/2013, while S. Costas’ was funded by IF/01047/2014. The following institutions have provided free access to essential data for the development of the publications that constitute this thesis: ESA and USGS for the satellite imagery; Puertos del Estado, and the Portuguese Hydrographic Institute in collaboration with CIMA for supplying oceanographic data; Ministry MITECO and DGSCM for data regarding beach sedimentology and nourishments.
Cabezas Rabadán, C. (2021). Beach Morphology and its Dynamism from Remote Sensing for Coastal Management Support [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165076
TESIS

Today there is new and stronger evidence that global warming is likely to have profound impacts on coastal communities and ecosystems. Accelerated sea-level rise, increased storminess, changes in water quality and coastal erosion as a consequence of global warming, are projected to pose increasing threats to coastal population, infrastructure, beaches, wetlands, and ecosystems. Coastal zones represent an irreplaceable and fragile ecological, economic and social resource that need to be preserved from the increasing coastal resources depletion, conflicts between uses, and natural ecosystems degradation. Accordingly, there is a growing importance of innovative integrated and multidisciplinary approaches to support the preservation, planning and sustainable management of coastal zones, considering the envisaged effects of global climate change. Climate change impacts in coastal zones are very dependent on regional geographical and environmental features, climate, and socio-economic conditions. Impact studies should therefore be performed at the local or at most at the regional level. In order to provide effective information that can assist coastal communities in planning sustainable adaptation measures to the effects of climate change, the main aim of this thesis is to develop a GIS-based Regional Risk Assessment (RRA) methodology for the integrated assessment of climate change impacts in coastal zones at the regional scale. The main aim of the RRA is to evaluate and rank the potential impacts, vulnerabilities and risks of climatic changes on coastal systems. Moreover the methodology allows the identification of key vulnerable receptors in the considered region and of homogeneous vulnerable and risk areas, that can be considered as homogeneous geographic sites for the definition of adaptation and management strategies. The present thesis complies with the research activities of the Euro-Mediterranean Centre for Climate Change (CMCC) and was implemented in a Decision support System for Coastal climate change impact assessment (DESYCO). In order to characterize climate related hazards and vulnerable receptors the RRA approach integrates downscaled climate, circulation and wave models output for the construction of future climate change scenarios and includes the analysis of site-specific physical, ecological and socio-economic characteristics of the territory (e.g. coastal topography, geomorphology, presence and distribution of vegetation cover, location of artificial protection). The RRA methodology was applied to the coastal area of the North Adriatic sea, in order to analyze the potential consequences of sea-level rise, relative sea-level rise inundation and coastal erosion impacts on multiple coastal receptors (i.e. beaches, river mouths, wetlands, terrestrial biological systems, protected areas, urban areas and agricultural areas) and compare the results based on multiple climate change scenarios. The main output of the analysis include exposure, susceptibility, risk and damage maps that could be used to support coastal authorities in the implementation of sustainable planning and management processes. Exposure maps obtained for the permanent inundation impacts (i.e. sea-level rise and relative sea-level rise) in 2100 allowing identification of coastal areas where the territory would be more submerged by projected water levels (i.e. areas surrounding the Po River Delta and the hinterland region between the Northern Venice lagoon and the Grado-Marano lagoons). Future exposure scenarios of coastal erosion depict a worse situation in winter and autumn for the future period 2070-2100 and highlight hot-spot exposure areas surrounding the Po River Delta. Susceptibility maps highlighted that the receptors more susceptible to coastal erosion are the beaches with about 94% of the territory identified by the very high and high susceptibility class. Risk maps showed that receptors with very high risk scores for the sea-level rise impact are wetlands, agricultural areas, protected areas and river mouths. The municipalities more interested by potential loss of beaches due to relative sea-level rise inundation are Ariano nel Polesine, Porto Viro, Porto Tolle, and Caorle. The receptors at higher risk for coastal erosion are the beaches where the percentage of the territory with higher risk scores is about 72% in the winter, 21% in the spring, 14% in the summer and 41% in autumn. Finally, the damage assessment phase showed that the receptors with by higher percentages of the territory in the medium and high damage classes are wetlands, agricultural areas, protected areas and river mouths for the sea-level rise inundation; beaches, wetlands and river mouths for the coastal erosion impact.
I cambiamenti climatici arrecheranno crescenti impatti sulle aree costiere e gli ecosistemi connessi attraverso un possibile aumento del livello del mare e dei processi di erosione costiera. Allo scopo di eseguire una valutazione integrata di questi impatti su diversi bersagli e guidare la definizione di strategie di adattamento a scala regionale è stata sviluppata una metodologia di Analisi di Rischio Regionale (ARR) su base GIS. Tale metodologia si avvale degli output di modelli climatici e idrodinamici per costruire scenari di pericolo legato al cambiamento climatico a scala regionale e analizza le caratteristiche intrinseche del territorio (es. aspetti bio-fisici, ecologici e socio-economici) per valutarne la vulnerabilità. I risultati dell'analisi comprendono mappe di esposizione, suscettibilità, rischio e danno utili per identificare, visualizzare e prioritizzare bersagli ed aree a rischio nella stessa regione e per guidare la definizione di strategie per la gestione dei rischi.

Nowadays, one of the urgent issues in the management of river basin resources as land degradation, especially soil erosion risk occurs due to complex factors of climate, cultivation practices of human and impacting of the operation of socio-economic development taking place in the basin. Soil erosion has been considered as the primary cause of soil degradation since soil erosion leads to the loss of topsoil and soil organic matters, which are essential for the growing of plants. Ta Trach river watershed, is a mountainous basin lying to the West - South of Thua Thien Hue province, having complex terrain. The result of this study showed that the amount of sediment yield accounts for high percentage. The average annual sedimentation is 41.60 tones per hectometer in the period of 2005 to 2010, soil erosion were classified by 5 levels. In which, the less deleterious erosion level still occupies high percentage with more than 55 % of watershed area. The main area of less deleterious soil erosion was located at high topography and high slope. The area of deleterious soil erosion occupies percentage lower than 22.63% of the entire basin, but it is also a warning sign to the extent of land degradation taking place in the basin if the erosion rate increases in the future.
Ngày nay, một trong những vấn đề cấp bách trong quản lý tài nguyên lưu vực sông là sự thoái hóa đất và đặc biệt là nguy cơ xói mòn đất xảy ra do yếu tố khí hậu phức tạp, phương thức canh tác của con người và tác động của những hoạt động phát triển kinh tế - xã hội đang diễn ra ở lưu vực. Lưu vực sông Tả Trạch là một lưu vực miền núi nằm về phía Tây - Nam của tỉnh Thừa Thiên Huế, có địa hình khá phức tạp. Mục tiêu của nghiên cứu này là ứng dụng công cụ SWAT để mô phỏng xói mòn đất ở lưu vực sông Tả Trạch thuộc tỉnh Thừa Thiên Huế từ năm 2005 đến năm 2010. Kết quả của nghiên cứu cho thấy lượng đất bồi lắng ở lưu vực chiếm tỷ lệ cao, trung bình mỗi năm bồi lắng 41.60 tấn/ha trong giai đoạn 2005 đến 2010, mức độ xói mòn được phân cấp thành 5 cấp xói mòn. Trong đó, mức độ xói mòn ít nguy hại chiếm ở tỷ lệ cao hơn 55 % diện tích lưu vực, chủ yếu phân bố ở những khu vực có địa hình cao, độ dốc lớn. Diện tích xói mòn nguy hại chiếm tỷ lệ thấp hơn 22,63% diện tích toàn lưu vực nhưng đây cũng là một dấu hiệu báo động cho mức độ thoái hóa đất diễn ra ở lưu vực trong tương lai nếu mức xói mòn này tăng lên.

Thesis (MScEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: As the world finds itself increasingly unable to avoid the negative impacts of the physical phenomena associated with climate change, adaptation to climate change has been brought to the forefront of the international agenda. The range of adaptation technologies available can be categorized into three basic strategies (IPCC, 1990): Protection, (managed) Retreat, or Accommodation. The practice of adapting existing developments and infrastructure in the coastal zone by the process of accommodation has not yet seen wide implementation as a formalised adaptation strategy. In order for a community to accept and successfully implement accommodation strategies, all community stakeholders are required to accept and live with a certain level of managed risk, and to also rethink the concept of failure. As a result, accommodation practices implemented globally have been closely related to fields such as risk - and disaster management. Structural innovations in the field of accommodation measures include advanced technologies to elevate existing buildings safely above flood levels, and even “amphibious” houses. In Cape Town, South Africa, the choice between protection, retreat or accommodation as an adaptation measure remains complex. Not much discussion has yet been generated concerning accommodation measures that could be implemented to reduce the risk to existing properties that are already inappropriately located in the risk zone (e.g. seaward of the coastal hazard line), by accommodating the dynamic coastal processes taking place. Accommodation has been found to be most feasible in Cape Town at case study sites with a stable, non- or slowly eroding shoreline, which are also subject to flooding. The elevation of buildings and the alteration of buildings for flood-proofing, in unison with proactive risk and disaster management, could be implemented to accommodate the impacts of flooding on affected infrastructure. Located on Cape Town’s Atlantic Seaboard, Bakoven serves as a case study sample of such a site where an accommodation-based adaptation solution could be feasible. Both global and regional downscaled climate models have been found to deliver a large range of future climate conditions. Assuming best estimate future predictions, Bakoven properties have been found vulnerable to extreme flooding during both status quo and future extreme events. Environmental conditions at Bakoven are favourable for the construction of piled foundations. Stringent environmental and heritage constraints imposed by local government would, however, render accommodation strategies unviable. It is recommended that government at all levels be willing to adopt a more flexible approach to governing coastal areas, to ensure that the regulations they impose remain as dynamic as the environments which they govern. The viability and possible benefits of accommodation measures, rather than protection or retreat approaches should be carefully considered on an individual case-by-case basis, in unison with the local community.
AFRIKAANSE OPSOMMING: Wêreldwyd is gemeenskappe besig om toenemend te ervaar dat hul nie die nadelige gevolge van klimaatsverandering kan vryspring nie. Juis daarom, is aanpassing tot klimaatsverandering noodsaaklik. Die verskeidenheid van beskikbare benaderinge tot klimaatsverandering aanpassing kan in drie hoof kategorieë ingedeel word, volgens die IPCC (1990): Beskerming, (stelselmatige) Retireer of Akkomodasie. Die aanpassing van bestaande infrastruktuur d.m.v. akkomodasie is nog nie wyd geïmplementeer as ‘n amptelike aanpassings strategie nie. Ten einde die sukses van ‘n akkommodasie strategie te verseker, sal gemeenskappe genoodsaak wees om ‘n sekere vlak van residuele risiko te aanvaar en die konsep van die ‘faling’ te herdefinieer. Akkommodasie oplossings wêreldwyd is daarom nouliks verwant aan risiko- en rampsbestuur. Innovasies in die struktuurindustrie om die risiko van klimaatsverandering te akkommodeer, sluit onder andere in die fisiese oplig van geboue na ‘n hoër, veilige vlak, en ook die bou van sogenaamde “amfibiese” huise. In Kaapstad is die bepaling van die mees gepaste en voordelige aanpassings oplossing, net soos in die res van die wêreld, kompleks. Die moontlikheid van die gebruik van akkommodasie benaderinge en tegnologieë, eerder as beskermingsstrategieë, is nog nie welbekend of algemeen geïmplementeer nie. Daar bestaan wel ‘n geleentheid om hierdie tegnologieë toe te pas in die geval van bestaande strukture wat seewaarts van die dinamiese kusproses lyn, geleë is. Hierdie studie het bevind dat akkommodasie oplossings moontlik suksesvol kan wees by spesifieke gevallestudies langs Kaapstad se kuslyn waar die kuslyn grootendeels stabiel is. Die oplig en verandering van geboue om vloedbestand te wees, tesame met proaktiewe risiko- en rampsbestuur maatreëls, word by sommige van hierdie gevallestudies aanbeveel om die impak van klimaatsverandering te akkomodeer. Bakoven, ‘n klein gemeenskapsbuurt op Kaapstad se kuslyn, is ‘n voorbeeld van ‘n geval waar ‘n akkommodasie oplossing moontlik goed kan werk. Globale klimaatsmodelle lewer ‘n wye reeks van toekomstige klimaatsvoorspellings vir die jaar 2063. Tydens die toets van die mees waarskynlike toekomstige klimaats-scenario, is bevind dat Bakoven kwesbaar is vir die verwagte vloeding a.g.v. seevlakstyging verwag teen 2063. Daar is ook bevind dat selfs tydens huidige storms, sommige strukture aan Bakoven se kus kwesbaar is. Die omgewingstoestande by Bakoven word beskou as voordelig vir die konstruksie van heipale as fondasies om die geboue hoër op te lig. As gevolg van streng munisipale regulasies met omgewings- en geskiedkundige bewaring as doel, is hierdie opsie egter nie moontlik nie. Dit word aanbeveel dat die regulasies wat deur regeringsamptenare daargestel word, aanpasbaar genoeg moet wees om die veranderende kusomgewing in ag te neem. Die moontlikheid en volhoubaarheid van ‘n akkommodasie oplossing, eerder as ‘n beskermings- of opgee benaderinge, moet deeglik ondersoek word vir elke ‘n individuele geval, in samewerking met die betrokke gemeenskap.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Considerada a primeira capital do CearÃ, o MunicÃpio de Aquiraz, dotado de caracterÃstica Ãmpar, guarda em seu entorno um arcabouÃo histÃrico e cultural, possui belas praias, morfologias e importantes ecossistemas, dos quais se integram e resultam numa complexidade geoambiental, do qual faz parte costa leste do Estado do CearÃ, dista da capital em 24,7km e apresenta um litoral com 10,5 km representados pelas praias da Prainha, PresÃdio, Iguape e Barro Preto. AtraÃdos pela beleza deste espaÃo, provocou um crescimento repentino da populaÃÃo abastarda de Fortaleza ocupando setores do litoral sem a mÃnima infra-estrutura e suporte ambiental iniciado no fim da dÃcada de 1960. As casas de veraneio foram o ponto de partida na construÃÃo sobre as dunas, faixa de praia e margens dos recursos hÃdricos, seguidas por investimentos pÃblicos e privados ligados ao turismo na implementaÃÃo de estruturas de grande porte a nÃvel internacional. Desprovidos de compromisso para com o meio ambiente e desrespeito as comunidades tradicionais, apoiado pelo poder pÃblico, refletiram numa sÃrie de degradaÃÃes ambientais com alteraÃÃes na dinÃmica sedimentar costeira. Nessa perspectiva, a pesquisa se deu em compreender os processos morfodinÃmicos local de forma a permitir tendÃncias de erosÃo e/ou progradaÃÃo da linha de costa. O monitoramento promoveu a caracterizaÃÃo das variÃveis intrÃnsecas nos processos de suprimento e retirada dos sedimentos da faixa de praia. Associando as atividades humanas, foi realizado um levantamento do processo de ocupaÃÃo no litoral e dos aspectos socioeconÃmicos, bem como na aplicaÃÃo de questionÃrios as comunidades e turistas. Problemas como: poluiÃÃo das Ãguas, retirada da mata ciliar e do mangue, desmonte de dunas, compactaÃÃo da areia de praia, dÃficit sedimentar e avanÃo do mar, desvio do curso d Ãgua, invasÃo da areia sobre as casas e conflitos sociais, foram os impactos negativos encontrados na Ãrea mediante a falta de leis ambientais e uso irracional dos recursos naturais.Urge a adoÃÃo de medidas preventivas e corretivas que contemplem o ordenamento territorial e a elaboraÃÃo do plano de gestÃo costeira para o litoral leste de Aquiraz criando Ãreas de proteÃÃo aos ambientes de importÃncia ecolÃgica e vulnerÃveis à ocupaÃÃo visando à qualidade de vida e sobrevivÃncia das comunidades locais e dos que deles provirÃo.
Considered the first capital of CearÃ, the City of Aquiraz, with unique feature, saves a framework in their environment and cultural history, has beautiful beaches, morphologies and important ecosystems, which are integrated and result in environmental complexity, which is part east coast of Cearà State, located 24.7 kilometers from the capital in and presents with a 10.5 kilometers coastline represented by the beaches of Prainha, Presidio, Iguape and Barro Preto. Attracted by the beauty of this area, caused a sudden growth of the population of Fortaleza corrupt occupying the coastal areas without any infrastructure and environmental support starts at the end of the 1960s. The houses of summer were the starting point in building on the dunes, beach and range of margins of water bodies, followed by public and private investments related to tourism in the implementation o structures of large internationally. Lack of commitment to the environment and disrespect the traditional communities, supported by the public, reflected in a number of environmental damage with changes in coastal sediment dynamics. Accordingly, the research was to understand the local morphodynamic processes to enable trends of erosion and / or advanced line of coast. Tracking promoted the characterization of the variables inherent in the processes of sediment supply and removal of the strip of beach. Involving human activities, a survey was performed of the occupation on the coast and the socioeconomic aspects as well as the application of questionnaires communities and tourists. Problems such as water pollution, deforestation of riparian forest and mangrove, removal of sand dunes, the compaction of beach sand, sediment deficit and advance of the sea, diversion of water courses, the invasion of sand on the homes and social conflicts were negative impacts found in the area by the lack of environmental laws and irrational use of natural resources. It is urgent the adoption of preventive and corrective measures that address the planning and development of coastal management plan for the east coast of Aquiraz creating areas of protection of the environment and vulnerable ecological importance to the occupation to the quality of life and survival of local communities and they will come.

Coastal aquifers are in hydraulic contact with the sea; prolonged overpumping of groundwater can lead to inland encroachment and/or vertical up-coning of the interface (transition or mixing zone) between these regimes, causing salt contamination of freshwater aquifers. In the Mediterranean area, seawater intrusion (SWI) has sometimes become a major threat to coastal area freshwater resources, mainly due to lack of appropriate groundwater resources management. Current projections of future potential climatic scenarios further complicate the overview, because the worst considered possibilities provide critical predictions about the decline of the average amount of water available (in terms of both inflows and outflows); furthermore, the projected sea-level rise (SLR) could significantly alter the position and morphology of coastline. A proper analysis and risk assessment of areas subject to SWI, and the evaluation of the coastal basins hydrological response to climate variability, appear to be essential for the design of water management measures that are necessary to mitigate environmental and socio-economic impacts. The key objectives of the study are: 1) development of a methodology of SWI risk analysis in coastal aquifers; 2) application of the methodology to a real case-study (Gaza Strip coastal aquifer, Palestinian Territories) to assess the risk of saltwater ingression and 3) analysis of the effectiveness of mitigation strategies on SWI Risk to support the planning of future spatial and territorial organization. The aquifer system is studied with a simulation code to assess the feasibility of risk mitigation measures under climate induced changes, by the means of simulation/optimization methods, which can provide the quantitative information needed for the management of groundwater resources, with respect to assigned objectives and constraints. Results show that (i) SWI risk assessment can be addressed by means of groundwater simulation models, calibrated against field measures, as a tool to evaluate future contamination in response to projected climate scenarios and exploitation plans, and that (ii) mitigation measures can be developed, according to some predefined criteria, and expected benefits can be quantified. The research is carried out within the CLIMB project, funded by the 7th Framework Programme of the European Commission.

Extreme weather events have become a common occurrence and coastal communities are adversely affected by it. Studies have shown that the changing climate has increased the frequency and severity of storms, surging sea levels, and floods, as was seen with Hurricane Sandy (2012) and Typhoon Haiyan (2013). The need to be proactive in preparing for these events, as a means of climate change adaptation and disaster risk reduction, is evident. This study focuses on the formal definition, measurement and simulation of coastal community preparedness and response to severe storm events. Preparedness and response requires resources, emergency plans, informed decision making and the ability to cope with unexpected events. A suite of preparedness indicators is developed using a three level hierarchical framework in the construction of a coastal community preparedness index to evaluate resources and plans. Informed decision making for emergency management personnel in the Emergency Operations Centre (EOC) is evaluated through a table-top exercise using a five-phase approach. Lastly, decision making with risk is introduced with a storm decision making simulation model. This study is applied to the case of the breakwater failure in the coastal community of Little Anse, Cape Breton, Nova Scotia.

Les plages du littoral varois se sont progressivement réduites depuis la seconde moitié du XXème siècle et ne survivent le plus souvent que grâce à de coûteux rechargements. Dans ce contexte, la réponse du milieu et l’intensité du risque dépendent d’abord du soutien sédimentaire apporté par les fleuves côtiers. Cette étude a ainsi pour but de quantifier les apports terrigènes du Gapeau à son embouchure et ses plages limitrophes dans la rade d’Hyères durant des crues et tempêtes. Nous avons mesuré le transport solide dans le cours d’eau, utilisé des formules de transport théorique et analysé l’évolution événementielle et séculaire de la bande active et de la bathymétrie littorale. Il ressort de cette étude un important phénomène de rétraction et d’érosion qui touche l’ensemble du secteur depuis 1896 et une faiblesse des apports sédimentaires actuels. Les pertes sédimentaires annuelles moyennes estimées sur le littoral sont supérieures aux apports sédimentaires fluviaux annuels moyens
The Var beaches have been gradually reduced during the second half of the twentieth century and they survive mostly thanks to costly artificial recharge. In this context, the response of the environment and the risk intensity depend primarily on the sedimentary support provided by the coastal rivers. This study looks to quantify the role of sediments transported by the Gapeau with particular reference to its mouth and neighbouring beaches during flood and storm events. We study the solid load measured in the river, theoretical transport equations in the literature and the evolution of the channel and Hyeres’s coastal bathymetry during the last century and during events. These analyses reveal important retraction and erosion that has impacted upon the area since 1896 and the current low sediment supply. The estimated average annual sediment losses along the coast are higher than the average annual river sediment supply

Thesis (MBA)--Stellenbosch University, 2005
ENGLISH ABSTRACT: Strong scientific evidence suggests that global warming is altering the world's climate and that this phenomenon is being accelerated as a result of human activities. Climate change is affecting weather patterns and, in addition to demonstrated sea-level rise, these in turn have and are likely to continue having significant, mostly negative, impacts - both economic and loss of life - on governments, industries and people. Ocean levels rose between 15 and 20 centimeters in the 20th century, mostly as a result of melting glaciers and thermal expansion of the oceans. The International Panel on Climate Change (IPCC, 2001a: 16) in its 2001 estimate suggests a potential rise in average sea level from nine to 88 centimeters from 1990 to 2100. Areas of risk in the City of Cape Town are residential property, infrastructure and beaches in low-lying areas. These areas are likely to be impacted as a result of increasing sea-level rise and increasing severity and frequency of storms. This study seeks to • demonstrate that sufficient evidence exists to compel decision-makers in the City of Cape Town that climate change and the impacts of sea-level rise and increasing frequency and severity of storms need to be considered in development planning; and • test cost-benefit analysis (through climate change impact analysis) as a tool for decision-makers to consider adaptation measures, using Langebaan as a case study. The research comprises a comprehensive literature study of the impacts of climate change, particularly with respect to coastal areas. A case study based on the eroding beaches at Langebaan is used to test cost-benefit analysis as a tool for decision-makers in dealing with the impacts. Despite the uncertainties associated with the impacts of climate change (time, place and extent) the issues of sea-level rise and severe storms seem to warrant further investigation, especially at a local level. This study provides local context to a global problem and makes recommendations for decision-makers in the City of Cape Town. Climate impact analysis (incorporating cost-benefit analysis) is suggested as a tool to quantify avoided damages at vulnerable coastal sites in the City of Cape Town. In conclusion, the impacts of climate change are a complex and multivariate problem. However, there are a number of identified vulnerable areas along the coastline of the City of Cape Town and using tools like climate impact analysis and cost-benefit analysis may assist in identifying, costing and managing these economic risks before the problem becomes unmanageable - a case for quantifying avoided damage.
AFRIKAANSE OPSOMMING: Sterk wetenskaplike bewyse bestaan dat globale verwarming besig is om die wêreld se klimaat te verander en hierdie verskynsel word versnel deur die mens se handelinge. Klimaatsverandering affekteer weerpatrone en bykomend tot gedemonstreerde stygende seevlakke, sal dit waarskynlik 'n langdurige en meestal negatiewe impak - beide ekonomies en lewensverlies - op regerings, industrieë en mense hê. Seevlakke het in die twintigste eeu met tussen 15 en 20 sentimeter gestyg, meestal as gevolg van smeltende ysberge en hitte uitsetting van die oseane. Die 'International Panel on Climate Change' (IPCC, 2001a: 16) het in hul skatting 'n waarskynlike seevlak styging van tussen 9 en 88 sentimeters voorspel vir die tydperk 1990 - 2100. Risikogebiede in die Stad Kaapstad is residensiële gebiede, infrastruktuur en strande in laagliggende gebiede. Hierdie gebiede sal ge-affekteer word deur stygende seevlakke en groter en meer gereelde storms. Hierdie studie poog om • te demonstreer dat voldoende bewyse bestaan om besluitnemers van die Stad Kaapstad te oortuig dat weerveranderinge en die impak van seevlakstygings en toenemende storms in aanmerking geneem moet word in ontwikkelings beplanning; en • koste-voordeel analises (deur klimaatsverandering impak analises) te beproef as 'n hulpmiddel vir besluitnemers om aanpasbare maatreëls te oorweeg, deur Langebaan as 'n voorbeeld te gebruik. Ten spyte van onsekerhede wat saamgaan met die impak van klimaatverandering (tyd, plek en omvang) regverdig die problem van stygende seevlakke en erge storms verdere ondersoek, meer spesifiek op plaaslike vlak. Hierdie studie gee plaaslike konteks aan 'n globale probleem en maak aanbevelings aan beplanners van die Stad Kaapstad. Klimaat impak analises word as hulpmiddel voorgestel om vermybare skades by kwesbare kusgebiede in die Stad Kaapstad te kwantifiseer. Ten slotte: die impak van klimaatsverandering is 'n komplekse probleem met baie fasette. Nietemin is daar verskere sensitiewe areas langs die kus van Stad Kaapstad, en klimaat impak analises en koste-voordeel analises kan help met die identifisering, kosteberekening en bestuur van hierdie ekonomiese risiko areas, voordat dit onhanteerbaar raak.

Video monitoring of beaches is becoming the preferred method for observing changes to nearshore morphology. Consequently this work investigates a new technique for predicting the probability of inundation that is based on measuring runup variation using video. Runup is defined as the water-level elevation maxima on the foreshore relative to the still water level and the waterline is defined as the position where the MWL intersects the beach face. Tairua, and Pauanui Beaches, on the north east coast of the North Island of New Zealand, were used as the field site in this study and represent two very different beaches with the same incoming wave and meteorological conditions. Tairua is most frequently in an intermediate beach state, whereas Pauanui is usually flatter in nature. In order to rectify runup observations, an estimate of the runup elevation was needed (Z). This was estimated by measuring the variation of the waterline over a tidal cycle from time-averaged video images during a storm event and provided beach morphology statistics (i.e. beach slope (α) and beach intercept (b)) used in the rectification process where Z=aX+b. The maximum swash excursions were digitized from time-stacks, and rectified to provide run-up timeseries with duration 20 minutes. Field calibrations revealed a videoed waterline that was seaward of the surveyed waterline. Quantification of this error gave a vertical offset of 0.33m at Tairua and 0.25m at Pauanui. At Tairua, incident wave energy was dominant in the swash zone, and the runup distributions followed a Rayleigh distribution. At Pauanui, the flatter beach, the runup distributions were approximately bimodal due to the dominance of infragravity energy in the swash signal. The slope of the beach was a major control on the runup elevation; runup at Pauanui was directly affected by the deepwater wave height and the tide, while at Tairua there was no correlation. Overall, the results of the study indicate realistic runup measurements, over a wide range of time scales and, importantly, during storm events. However, comparisons of videoed runup and empirical runup formulae revealed larger deviations as the beach steepness increased. Furthur tests need to be carried out to see if this is a limitation of this technique, used to measure runup. The runup statistics are consistently higher at Tairua and suggests that swash runs up higher on steeper beaches. However, because of the characteristics of flatter beaches (such as high water tables and low drainage efficiencies) the impact of extreme runup elevations on such beaches are more critical in regards to erosion and/ or inundation. The coastal environment is of great importance to Māori. Damage to the coast and coastal waahi tapu (places of spiritual importance) caused by erosion and inundation, adversely affects the spiritual and cultural well-being of Māori. For this reason, a chapter was dedicated to investigating the practices used by Māori to protect and preserve the coasts in accordance with tikanga Māori (Māori protocols). Mimicking nature was and still is a practice used by Māori to restore the beaches after erosive events, and includes replanting native dune plants and using natural materials on the beaches to stabilize the dunes. Tapu and rahui (the power and influence of the gods) were imposed on communities to prohibit and prevent people from free access to either food resources or to a particular place, in order to protect people and/ or resources. Interpretations of Māori oral histories provide insights into past local hazards and inform about the safety and viability of certain activities within an area. Environmental indicators were used to identify and forecast extreme weather conditions locally. Māori knowledge of past hazards, and the coastal environment as a whole, is a valuable resource and provides a unique source of expertise that can contribute to current coastal hazards management plans in New Zealand and provide insights about the areas that may again be impacted by natural hazards.

Dans un contexte de socialisation des risques, les propriétaires et gestionnaires d’espaces naturels sont confrontés à un paradoxe opposant l’exigence croissante d’un aménagement des sites en vue de leur sécurisation, et la nécessité d’assurer leur préservation. Cette problématique revêt un relief particulier dans les espaces naturels littoraux, qui concentrent des sites d’exception en termes de biodiversité et de paysages, qui sont dans le même temps prisés des touristes et sportifs, et entourés par l’urbanisation. La gestion naturaliste de ces espaces génère des risques, voire des dommages, et donne lieu à des responsabilités qui s’entrecroisent, voire s’enchevêtrent. Les espaces littoraux sont également concernés par les risques d’érosion côtière et de submersion marine qui illustrent la situation paradoxale du souhait d’occuper un espace d’exception, sans être impacté par son évolution. Face aux faiblesses des stratégies de défense contre la mer, l’idée d’une acceptation de la mouvance du trait de côte, par anticipation ou déplacement des enjeux menacés, se fraie un chemin depuis une trentaine d’années et conduit à repenser l’aménagement des sites côtiers et des espaces rétro-littoraux. Ainsi, si les acteurs de la gestion des espaces naturels se heurtent aujourd’hui aux demandes d’indemnisation des victimes de risques naturels, ils se heurteront demain aux demandes de protection ou de relocalisation des personnes menacées par les risques côtiers. Dès lors, comment répondre à ces enjeux et contraintes ? La thèse étaye le postulat selon lequel la clef réside dans une meilleure appréhension juridique de la notion de risques inhérents aux espaces naturels
In a context of risks socialization, the owners and the administrators of natural spaces are confronted to a paradox bringing into conflict the increasing demand of security in natural sites, and the necessity to assure the preservation of those same sites. Coastal zone are particularly faced with this problem : in fact, this kind of territories are characterized by some remarkable natural spaces and landscapes, which are both crowed by tourists and outdoor sports enthusiasts, and landlocked by the urbanization. Today, the wilderness management of natural spaces generates risks and responsibilities which become muddled between the littoral actors. Coastal zones are also exposed to erosion and marine submersion, which illustrate the paradoxical situation of the wish to live in exceptional spaces without undergoing the natural dynamics of the coastal line. In front of the weakness of defense strategies, the idea of an acceptance of the natural movement of the coast line by anticipation or spatial reorganization of territories to protect the persons threatened by erosion or submersion, gained ground in the last thirty years. These news adaptation strategies lead up to reconsider the coastal zones management, but also the hinterland spatial planning. Thus, if the actors of the natural spaces management face with the compensation claims of natural risks victims today, they will collide with requests of protection or relocation of the people threatened by the coastal risks tomorrow. How to answer to these stakes and constraints ? This thesis supports the postulate that the key lies in a better legal apprehension of the notion of risks inherent in natural spaces

Thesis (MScEng)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: The Strand is located within False Bay and frequently encounters large quantities of wave overtopping over the coastal defences. This results in the damage of property and infrastructure and causes streets to be flooded. Physical modelling tests were done by a consultancy firm to determine a solution by making use of a recurve structure at the back of the beach. This study is an expansion of the previous physical modelling that was done and focuses on several factors that were not tested by the consultancy firm that could have an influence on the overtopping rate and provide additional information on the recurve design. These tests were: (i) the effectiveness of the proposed recurve wall design in reducing overtopping was compared to a vertical wall; (ii) the influence that modifications to the beach profile such as the beach slope, beach width and beach level have on the overtopping rate; and (iii) the sensitivity of overtopping to changes in wave period was tested. The information gathered from these tests was used to propose a possible solution for the Strand. Numerical modelling was done with Delft3D-Wave to determine the wave height at the back of the beach using a nested grid. The waves at the Strand are depth limited and therefore very sensitive to changes in water level. By altering the beach level the model showed how the significant wave height at the back of the beach changes. First estimates of overtopping were determined using the relevant empirical calculations from the EuroTop Manual 2007 for a vertical seawall. No estimate could be made for the recurve wall since it did not fall in the valid range of the equations. From the physical modelling it was found that the overtopping reduced significantly from a vertical to a recurve seawall by a factor of about 50% depending on the wall height. All the prediction methods tested proved to be accurate in estimating the overtopping when the ratio of freeboard to significant wave height was ≤1.83. For non-breaking wave conditions the beach profiles that were gently sloped (1:50) and wide produced more overtopping than the beach profiles that were steep (1:10) and narrow. Increasing the beach level only decreased the overtopping if the water depth was shallow enough to cause the waves to break before they reached the back of the beach. Overtopping was found to increase with longer wave periods until the wave period became too long and the waves broke offshore which resulted in the overtopping decreasing. Possible solutions to overtopping were proposed based on two beach levels and the implementation of a recurve seawall. Revised crest levels for the wall were made along the length of the beach for both the 1:20 and 1:100 year water levels.
AFRIKAANSE OPSOMMING: Die Strand is in Valsbaai geleë en ervaar dikwels baie oorspoeling deur golwe bo-oor kusverdedigingswerke. Dit lei tot skade aan eiendom sowel as aan infrastruktuur en veroorsaak dat strate oorstroom. Fisiese modelleringstoetse is deur ’n konsultasiefirma gedoen om ’n oplossing te probeer vind deur van ’n teruggebuigde struktuur aan die agterkant van die strand gebruik te maak. Hierdie studie is ’n uitbreiding van die vorige fisiese modellering wat gedoen is en fokus op verskeie faktore wat nie deur die konsultasiefirma getoets is nie. Dit kan moontlik ’n invloed op die oorspoelingstempo hê en verskaf bykomende inligting oor die ontwerp van die terugbuiging. Hierdie toetse is: (i) die doeltreffendheid van die voorgestelde ontwerp van die teruggebuigde strandmuur in die vermindering van oorspoeling word vergelyk met ’n vertikale muur; (ii) die invloed wat veranderinge aan die strandprofiel soos die helling van die strand, die wydte van die strand asook die strandvlak op die oorspoelingstempo het; en (iii) die sensitiwiteit van oorspoeling op veranderinge in golfperiode is getoets. Die inligting wat uit hierdie toetse verkry is, word gebruik om ’n moontlike oplossing vir die Strand voor te stel. Numeriese modellering is met Delft3D-Wave gedoen om die golfhoogte aan die agterkant van die strand vas te stel deur van ’n genestelde ruitenet gebruik te maak. Die golwe by die Strand word deur diepte beperk en is dus baie sensitief vir veranderinge in die watervlak. Deur die strandvlakke te verander het die model getoon hoe die betekenisvolle golfhoogte aan die agterkant van die strand verander. Die eerste beramings van oorspoeling is bepaal deur van die relevante empiriese berekenings uit die EuroTop-handleiding 2007 vir ’n vertikale strandmuur gebruik te maak. Daar kon geen beraming vir die teruggebuigde muur gemaak word nie aangesien dit nie binne die geldige bereik van die vergelykings val nie. Uit die fisiese modellering is daar vasgestel dat oorspoeling noemenswaardig met ’n gemiddeld van ongeveer 50% verminder is, afhangend van die muurhoogte. Al die voorspellingmetodes wat getoets is was akkuraat in die beraming van die oorspoeling wanneer die verhouding van vryboord tot betekenisvolle golfhoogte ≤1.83 was. Vir nie-brekende golftoestande het strandprofiele met ’n lae helling (1:50) en wat wyd was meer oorspoeling tot gevolg gehad as strandprofiele wat steil (1:10) en nou was. ’n Verhoging in die strand se vlakke het die oorspoeling slegs verminder indien die diepte van die water vlak genoeg was om die golwe te laat breek voordat hulle die agterkant van die strand bereik het. Oorspoeling is gevind om te vermeeder met verlengde golflengte tot dat die golflengte só lank geword het dat die golwe in dieper water begin breek wat aanlieding tot verminderde oorspoeling gegee het. Daar word moontlike oplossings vir oorspoeling voorgestel gebaseer op twee strandvlakke en die implementering van ’n teruggebuigde strandmuur. Voorgestelde golfkruinvlakke vir die muur is al langs die lengte van die strand gemaak vir beide die 1:20- en 1:100-jaar watervlakke.

An ecological risk assessment was conducted on the risk to fish of chemical contaminants detected in the habitat of Albula vulpes in South Florida, to evaluate whether contaminants may be a driver of declines in the recreational bonefish fishery. All available contaminant detection data from Biscayne Bay, Florida Bay, and the Florida Keys were compared to federal and state guidelines for aquatic health to identify Contaminants of Potential Ecological Concern (COPECS). For these COPECs, species sensitivity distributions were constructed and compared with recent detections at the 90th centile of exposure. Copper in Biscayne Bay was identified as the highest risk of acute and chronic effects to fish, followed by a risk of chronic effects from both the recently phased-out pesticide endosulfan in Florida Bay, and the pharmaceutical hormone estrone in the Florida Keys.

Studies of the dunefield systems crossing the Cape St. Francis headland in the Eastern Cape have focused on the role that wind plays in sediment transfer in coastal dunefield systems, with limited consideration of the role of water. The aim of this study was to improve understanding of the morphology, processes and patterns within the Oyster Bay HBD system, focussing particularly on surface water and groundwater interactions and the role of surface water in sediment transfer across the dunefield system. An extensive field survey was conducted, to collect related data, complimented by spatial and temporal analysis of the study area using GIS. The key findings from this research were the apparent differences between the western and eastern regions of the dunefield with regard to specific drivers and the respective processes and responses. Wind is the major driver of change up to and across the crest of the dunefield. In the eastern region water (ground water, surface water and the Sand River System) is the primary agent of sediment flux through processes of aggregation and slumping as well as episodic events including debris flows. This study has highlighted a need for further quantitative studies that investigate the movement of sediment through dunefield systems such as this (where water is at or near the land surface). The paradigm that sediment flux is entirely due to wind is almost certainly simplistic, and deeper understanding of these systems is needed
Maiden name: Elkington, Lauren

Las zonas costeras, y en especial las playas, son la unión principal entre la tierra y el mar, siendo el escenario de infinidad de interacciones causadas por factores muy diversos, desde cambios producidos por la dinámica natural de la zona hasta los producidos por la creciente presión humana. Por este motivo, se trata de zonas con mucha variabilidad espacio-temporal, diversidad y funcionalidad que dan lugar a diferentes paisajes, usos y actividades. Desafortunadamente, siempre se ha gestionado la zona costera de manera desintegrada, sin considerar todos los factores e interacciones que en ella ocurren, dando lugar a importantes impactos que ponen en jaque la supervivencia de muchas zonas costeras. En el caso de estudio del delta de la Tordera y sus playas, la erosión costera es una consecuencia de una combinación de varios factores, caracterizados por diferentes escalas temporales y espaciales así como de diferente naturaleza como son: la explotación del acuífero, la construcción de escolleras en la desembocadura, los dragados de arena tanto en el río como en el delta sumergido, los cambios en los usos del suelo, la construcción del paseo marítimo, las estructuras de defensa y artificialización de la costa, los cambios en la vegetación de ribera o la reducción del ancho efectivo del río, entre muchos otros. Estos ejemplos, muchos de los cuales son globales en todos los deltas, ponen de manifiesto el modelo de gestión tradicional de estas zonas, una gestión enfocada al aprovechamiento puntual, sin una visión global de ecosistema y, sobretodo, una gestión reactiva a las consecuencias que iban surgiendo, lo que hemos llamado una gestión desintegrada de la zona costera. Para acabar con dicha gestión desintegrada, a principios del siglo XXI, se creó lo que se conoce como la Gestión Integrada de Zonas Costeras (GIZC) que incluía todos los sistemas que influyen en las playas en la propia gestión costera. El principal cambio es que la GIZC fomenta la gestión proactiva en lugar de la reactiva que se ha venido usando desde hace siglos. Por este motivo, el monitoreo de los procesos costeros es un paso crucial para conseguir una buena gestión, y no solo mediante el uso de herramientas ya consolidadas sino también mediante la modificación y/o creación de nuevas herramientas que permitan mejorar la capacidad de monitoreo. En esta tesis se proporcionan y validan distintas herramientas de monitoreo, tanto existentes cómo otras de nuevas, para que puedan ser usadas en el futuro por los gestores del territorio con el objetivo de conseguir una gestión más efectiva y sostenible de la zona del delta de la Tordera. En definitiva, se hace patente la necesidad de un nuevo modelo de gestión para zonas costeras que sea capaz de integrar toda la información disponible de los distintos subsistemas que conforman un ecosistema, relacionarlos entre ellos y establecer una serie de indicadores clave que sientan las bases de una planificación global e integrada por ecosistema, sin olvidar que la participación social en dicha gestión se trata de un punto clave para conseguir resultados a largo plazo. Así pues, es necesario que los gestores del territorio se muevan hacia un modelo de gestión costera por ecosistema que siga el marco y principios de la Gestión Integrada de Zonas Costeras (GIZC) que permita establecer un Plan Estratégico Integral y Global a largo plazo mediante el uso de herramientas de gestión adaptadas a cada caso particular.
The coastal areas, and especially the beaches, are the main union between the land and the sea, being the scene of countless interactions caused by different factors, from changes produced by the natural dynamics of the area to those produced by the growing human pressure. Unfortunately, the coastal zone has always been managed in a disintegrated manner, without considering all the factors and interactions that occur there, resulting in significant impacts that compromises the survival of many coastal areas. In the case of the Tordera delta and its beaches, coastal erosion is a consequence of a combination of several factors such as the aquifer exploitation, the construction of breakwaters at the mouth, the changes in land use or the reduction of the effective river width, among many others. These examples, many of which are global in all deltas, reveal the traditional management model of these areas, a management focused on timely use, that is, a disintegrated management of the coastal zone. To end with this management, at the beginning of the 21st century, what is known as Integrated Coastal Zone Management (ICZM) was created, which encourages proactive management instead of the reactive one that has been used for centuries. For this reason, monitoring of coastal processes is a crucial step to achieve good management. In this thesis different monitoring tools are provided and validated, both existing and new, so that they can be used in the future by the managers of the territory in order to achieve a more effective and sustainable management of the area of the Tordera delta. Definitely, it is necessary that the territorial managers move towards a model of coastal management by ecosystem that follows the framework and principles of Integrated Coastal Zone Management (ICZM) and that allows to establish an Integral and Global Strategic Plan in the long term through the use of management tools adapted to each particular case.

Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas
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Resumo: Durante as últimas décadas a demografia discutiu importantes conceitos ao tratar da relação entre dinâmica populacional e mudança ambiental. Surgiram novos caminhos, buscando compreender essa relação em análises centradas no entendimento do papel do espaço, dos padrões de produção e consumo, do risco e da vulnerabilidade. Recentemente, com a confirmação das estimativas das mudanças climáticas, a demografia é novamente desafiada a elucidar os elementos da dinâmica populacional que afetam o clima e que por ela são afetados. Nessa pesquisa objetiva-se compreender elementos desse segundo ponto, analisando riscos ambientais às mudanças climáticas em populações residentes em zonas costeiras. Mais especificamente, analisamos a dinâmica de três municípios costeiros do Estado de São Paulo, na Região Metropolitana da Baixada Santista: Bertioga, Guarujá e São Vicente. Tais municípios, majoritariamente urbanos, abrigam espaços diferenciados e desiguais, tanto do ponto de vista geográfico como social. Geograficamente, a presença de morros, rios, estuários e do próprio mar, condicionam a formação de riscos ambientais diferenciados. Socialmente, com a ocupação dos espaços para usos diversos (residenciais, turísticos e industriais), e por grupos com perfis sócio-econômicos particulares, cada um desses riscos atinge populações também específicas. A partir desses fatores a hipótese do trabalho é que populações com características distintas passam por diferentes riscos ambientais. Desse modo, os riscos que selecionamos são relativos às mudanças ambientais: a elevação do nível do mar, as inundações e os deslizamentos. Para cada um desses riscos, e de suas possíveis combinações, foram criadas zonas de risco, utilizando os dados de setores censitários. Os resultados indicaram a confirmação da nossa hipótese: populações mais pobres estão nas imediações de corpos d'água e morros, áreas onde a possibilidade das intensificações de inundações e deslizamentos é maior, enquanto as mais ricas localizam-se próximas ao mar, onde o maior risco é o da elevação do nível médio do mar
Abstract: Demography has discussed important concepts in concern with the relation between population dynamics and environmental change through last decades. New ways were developed and the role of space, patterns of production and consumption, risk and vulnerability were incorporated in theses analysis. Recently, with more accuracy estimates of climate change, demography is again challenged to elucidate the elements of population dynamics that affect climate and vice-versa. This research aims to understand this elements, analyzing risks of climate change on populations living in coastal areas. More specifically, we analyze the dynamics of three coastal municipalities of Sao Paulo State, in the Metropolitan Area of Baixada Santista: Bertioga, Guarujá and São Vicente. These municipalities, mostly urban, harbor differentiated and uneven spaces, both geographically and socially. Geographically, the presence of hills, rivers, estuaries and the sea, influence different environmental risks. Socially, space has been transformed according to several social uses (residential, tourist and industrial), resulting in specific groups, with particular socio-economic profiles, living in distinct risks zones. Based on these factors, the hypothesis adopted is that populations with different characteristics are replaced by different environmental risks. Therefore, the risks selected represent some of the environmental changes dangers: rising sea levels, more intensive flooding and landslides. For each of these risks, and their possible combinations were created risk areas, using data from census tracts. The results indicated the poorest are in the vicinity of ponds and hills, where the possibility of intensification of floods and landslides is higher, while the richest are sited near sea, where the greatest risk is the elevation of the average sea level
Mestrado
Demografia
Mestre em Demografia