Tuzla City (BiH): an example of geohazard induced by salt extraction

Salt deposits characterize the subsurface of Tuzla (BiH) and made it famous since the ancient times. Archeological discoveries demonstrate the presence of a Neolithic pile-dwelling settlement related to the existence of saltwater springs that contributed to make the most of the area a swampy ground. Since the Roman times, the town is reported as “the City of Salt deposits and Springs”; "tuz" is the Turkish word for salt, as the Ottomans renamed the settlement in the 15th century following their conquest of the medieval Bosnia (Donia and Fine, 1994). Natural brine springs were located everywhere and salt has been evaporated by means of hot charcoals since pre-Roman times. The ancient use of salt was just a small exploitation compared to the massive salt production carried out during the 20th century by means of classical mine methodologies and especially wild brine pumping. In the past salt extraction was practised tapping natural brine springs, while the modern technique consists in about 100 boreholes with pumps tapped to the natural underground brine runs, at an average depth of 400-500 m. The mining operation changed the hydrogeological conditions enabling the downward flow of fresh water causing additional salt dissolution. This process induced severe ground subsidence during the last 60 years reaching up to 10 meters of sinking in the most affected area. Stress and strain of the overlying rocks induced the formation of numerous fractures over a conspicuous area (3 Km2). Consequently serious damages occurred to buildings and infrastructures such as water supply system, sewage networks and power lines. Downtown urban life was compromised by the destruction of more than 2000 buildings that collapsed or needed to be demolished causing the resettlement of about 15000 inhabitants (Tatić, 1979). Recently salt extraction activities have been strongly reduced, but the underground water system is returning to his natural conditions, threatening the flooding of the most collapsed area. During the last 60 years local government developed a monitoring system of the phenomenon, collecting several data about geodetic measurements, amount of brine pumped, piezometry, lithostratigraphy, extension of the salt body and geotechnical parameters. A database was created within a scientific cooperation between the municipality of Tuzla and the city of Rotterdam (D.O.O. Mining Institute Tuzla, 2000). The scientific investigation presented in this dissertation has been financially supported by a cooperation project between the Municipality of Tuzla, The University of Bologna (CIRSA) and the Province of Ravenna. The University of Tuzla (RGGF) gave an important scientific support in particular about the geological and hydrogeological features. Subsidence damage resulting from evaporite dissolution generates substantial losses throughout the world, but the causes are only well understood in a few areas (Gutierrez et al., 2008). The subject of this study is the collapsing phenomenon occurring in Tuzla area with the aim to identify and quantify the several factors involved in the system and their correlations. Tuzla subsidence phenomenon can be defined as geohazard, which represents the consequence of an adverse combination of geological processes and ground conditions precipitated by human activity with the potential to cause harm (Rosenbaum and Culshaw, 2003). Where an hazard induces a risk to a vulnerable element, a risk management process is required. The single factors involved in the subsidence of Tuzla can be considered as hazards. The final objective of this dissertation represents a preliminary risk assessment procedure and guidelines, developed in order to quantify the buildings vulnerability in relation to the overall geohazard that affect the town. The historical available database, never fully processed, have been analyzed by means of geographic information systems and mathematical interpolators (PART I). Modern geomatic applications have been implemented to deeply investigate the most relevant hazards (PART II). In order to monitor and quantify the actual subsidence rates, geodetic GPS technologies have been implemented and 4 survey campaigns have been carried out once a year. Subsidence related fractures system has been identified by means of field surveys and mathematical interpretations of the sinking surface, called curvature analysis. The comparison of mapped and predicted fractures leaded to a better comprehension of the problem. Results confirmed the reliability of fractures identification using curvature analysis applied to sinking data instead of topographic or seismic data. Urban changes evolution has been reconstructed analyzing topographic maps and satellite imageries, identifying the most damaged areas. This part of the investigation was very important for the quantification of buildings vulnerability.

Multitemporal analysis of satellite imagery: implementation of a land evolution model in ALCS (ATSR LAND CLASSIFICATION SYSTEM)

In this report it was designed an innovative satellite-based monitoring approach applied on the Iraqi Marshlands to survey the extent and distribution of marshland re-flooding and assess the development of wetland vegetation cover. The study, conducted in collaboration with MEEO Srl , makes use of images collected from the sensor (A)ATSR onboard ESA ENVISAT Satellite to collect data at multi-temporal scales and an analysis was adopted to observe the evolution of marshland re-flooding. The methodology uses a multi-temporal pixel-based approach based on classification maps produced by the classification tool SOIL MAPPER ®. The catalogue of the classification maps is available as web service through the Service Support Environment Portal (SSE, supported by ESA). The inundation of the Iraqi marshlands, which has been continuous since April 2003, is characterized by a high degree of variability, ad-hoc interventions and uncertainty. Given the security constraints and vastness of the Iraqi marshlands, as well as cost-effectiveness considerations, satellite remote sensing was the only viable tool to observe the changes taking place on a continuous basis. The proposed system (ALCS – AATSR LAND CLASSIFICATION SYSTEM) avoids the direct use of the (A)ATSR images and foresees the application of LULCC evolution models directly to „stock‟ of classified maps. This approach is made possible by the availability of a 13 year classified image database, conceived and implemented in the CARD project (http://earth.esa.int/rtd/Projects/#CARD).The approach here presented evolves toward an innovative, efficient and fast method to exploit the potentiality of multi-temporal LULCC analysis of (A)ATSR images. The two main objectives of this work are both linked to a sort of assessment: the first is to assessing the ability of modeling with the web-application ALCS using image-based AATSR classified with SOIL MAPPER ® and the second is to evaluate the magnitude, the character and the extension of wetland rehabilitation.

Stratigraphy and Palaeontology of the Late Cretaceous Wapiti Formation, west-central Alberta, Canada

A complete stratigraphic assessment and revision of the middle Campanian to upper Maastrichtian Wapiti Formation in north-western Alberta and north-eastern British Columbia is the main aim of this research project. The study area encompasses an area of approximately 200X180 km in the Grande Prairie County (west-central Alberta) and easternmost British Columbia, Canada. Results presented here indicate that the 1300m thick succession currently reported in the literature as “undifferentiated lithostratigraphic unit”, consists of five lithostratigraphic units and four unconformity-bounded depositional sequences; their study and description have been documented integrating several geological disciplines, including sequence stratigraphic methods, well-log signatures, facies analysis, and fossil associations. On the whole, particular attention has been given to 1) age and nature of both basal and upper contacts of the Wapiti Formation, 2) effective mappability of lithostratigraphic units and depositional sequences in western Alberta, and 3) the identification of previously undetermined maximum flooding surface of the Bearpaw seaway and Drumheller Marine Tongue, which are reference marine unit in central and southern Alberta. A second, but not less important, guideline for the project has been the rich paleontological record of the Wapiti deposits. Detailed paleoenvironmental and taxonomical information on old and new finds have been the base for correlation with well known associations of Alaska, southern Alberta, and Montana. Newly discovered rich fossil localities documented an extraordinarily diverse fauna during the latest Cretaceous, including dinosaurs, squamates, and fresh-water fishes and reptiles. Lastly, in order to better characterize the Wapiti Formation, major marker beds were described: these include several bentonites (altered volcanic ash deposits) which have been documented over an area of almost 30.000 km2, as well as four major coal zones, characterized by tabular coal seams with an overall thickness of 2 meters. Such marker beds represent a formidable tool for high-resolution chronology and regional correlations within the Late Cretaceous Alberta foreland basin.

Evidenze micropaleontologiche e sedimentologiche di cicli deposizionali e climatici circa millenari nei Depositi Tardoquaternari della Piana dell'Arno e del Delta del Po

A multidisciplinary study was carried out on the Late Quaternary-Holocene subsurface deposits of two Mediterranean coastal areas: Arno coastal plain (Northern Tyrrhenian Sea) and Modern Po Delta (Northern Adriatic Sea). Detailed facies analyses, including sedimentological and micropalaeontological (benthic foraminifers and ostracods) investigations, were performed on nine continuously-cored boreholes of variable depth (ca. from 30 meters to100 meters). Six cores were located in the Arno coastal plain and three cores in the Modern Po Delta. To provide an accurate chronological framework, twenty-four organic-rich samples were collected along the fossil successions for radiocarbon dating (AMS 14C). In order to reconstruct the depositional and palaeoenvironmental evolution of the study areas, core data were combined with selected well logs, provided by local companies, along several stratigraphic sections. These sections revealed the presence of a transgressive-regressive (T-R) sequence, composing of continental, coastal and shallow-marine deposits dated to the Late Pleistocene-Holocene period, beneath the Arno coastal plain and the Modern Po Delta. Above the alluvial deposits attributed to the last glacial period, the post-glacial transgressive succession (TST) consists of back-barrier, transgressive barrier and inner shelf deposits. Peak of transgression (MFS) took place around the Late-Middle Holocene transition and was identified by subtle micropalaeontological indicators within undifferentiated fine-grained deposits. Upward a thick prograding succession (HST) records the turnaround to regressive conditions that led to a rapid delta progradation in both study areas. Particularly, the outbuilding of modern-age Po Delta coincides with mud-belt formation during the late HST (ca. 600 cal yr BP), as evidenced by a fossil microfauna similar to the foraminiferal assemblage observed in the present Northern Adriatic mud-belt. A complex interaction between allocyclic and autocyclic factors controlled facies evolution during the highstand period. The presence of local parameters and the absence of a predominant factor prevent from discerning or quantifying consequences of the complex relationships between climate and deltaic evolution. On the contrary transgressive sedimentation seems to be mainly controlled by two allocyclic key factors, sea-level rise and climate variability, that minimized the effects of local parameters on coastal palaeoenvironments. TST depositional architecture recorded in both study areas reflects a well-known millennial-scale variability of sea-level rising trend and climate during the Late glacial-Holocene period. Repeated phases of backswamp development and infilling by crevasse processes (parasequences) were recorded in the subsurface of Modern Po Delta during the early stages of transgression (ca. 11,000-9,500 cal yr BP). In the Arno coastal plain the presence of a deep-incised valley system, probably formed at OSI 3/2 transition, led to the development of a thick (ca. 35-40 m) transgressive succession composed of coastal plain, bay-head delta and estuarine deposits dated to the Last glacial-Early Holocene period. Within the transgressive valley fill sequence, high-resolution facies analyses allowed the identification and lateral tracing of three parasequences of millennial duration. The parasequences, ca. 8-12 meters thick, are bounded by flooding surfaces and show a typical internal shallowing-upward trend evidenced by subtle micropalaeontological investigations. The vertical stacking pattern of parasequences shows a close affinity with the step-like sea-level rising trend occurred between 14,000-8,000 cal years BP. Episodes of rapid sea-level rise and subsequent stillstand phases were paralleled by changes in climatic conditions, as suggested by pollen analyses performed on a core drilled in the proximal section of the Arno palaeovalley (pollen analyses performed by Dr. Marianna Ricci Lucchi). Rapid shifts to warmer climate conditions accompanied episodes of rapid sea-level rise, in contrast stillstand phases occurred during temporary colder climate conditions. For the first time the palaeoclimatic signature of high frequency depositional cycles is clearly documented. Moreover, two of the three "regressive" pulsations, recorded at the top of parasequences by episodes of partial estuary infilling in the proximal and central portions of Arno palaeovalley, may be correlated with the most important cold events of the post-glacial period: Younger Dryas and 8,200 cal yr BP event. The stratigraphic and palaeoclimatic data of Arno coastal plain and Po Delta were compared with those reported for the most important deltaic and coastal systems in the worldwide literature. The depositional architecture of transgressive successions reflects the strong influence of millennial-scale eustatic and climatic variability on worldwide coastal sedimentation during the Late glacial-Holocene period (ca. 14,000-7,000 cal yr BP). The most complete and accurate record of high-frequency eustatic and climatic events are usually found within the transgressive succession of very high accommodation settings, such as incised-valley systems where exceptionally thick packages of Late glacial-Early Holocene deposits are preserved.

Analysis and developments of uncertainty processors for real time flood forecasting

The hydrologic risk (and the hydro-geologic one, closely related to it) is, and has always been, a very relevant issue, due to the severe consequences that may be provoked by a flooding or by waters in general in terms of human and economic losses. Floods are natural phenomena, often catastrophic, and cannot be avoided, but their damages can be reduced if they are predicted sufficiently in advance. For this reason, the flood forecasting plays an essential role in the hydro-geological and hydrological risk prevention. Thanks to the development of sophisticated meteorological, hydrologic and hydraulic models, in recent decades the flood forecasting has made a significant progress, nonetheless, models are imperfect, which means that we are still left with a residual uncertainty on what will actually happen. In this thesis, this type of uncertainty is what will be discussed and analyzed. In operational problems, it is possible to affirm that the ultimate aim of forecasting systems is not to reproduce the river behavior, but this is only a means through which reducing the uncertainty associated to what will happen as a consequence of a precipitation event. In other words, the main objective is to assess whether or not preventive interventions should be adopted and which operational strategy may represent the best option. The main problem for a decision maker is to interpret model results and translate them into an effective intervention strategy. To make this possible, it is necessary to clearly define what is meant by uncertainty, since in the literature confusion is often made on this issue. Therefore, the first objective of this thesis is to clarify this concept, starting with a key question: should be the choice of the intervention strategy to adopt based on the evaluation of the model prediction based on its ability to represent the reality or on the evaluation of what actually will happen on the basis of the information given by the model forecast? Once the previous idea is made unambiguous, the other main concern of this work is to develope a tool that can provide an effective decision support, making possible doing objective and realistic risk evaluations. In particular, such tool should be able to provide an uncertainty assessment as accurate as possible. This means primarily three things: it must be able to correctly combine all the available deterministic forecasts, it must assess the probability distribution of the predicted quantity and it must quantify the flooding probability. Furthermore, given that the time to implement prevention strategies is often limited, the flooding probability will have to be linked to the time of occurrence. For this reason, it is necessary to quantify the flooding probability within a horizon time related to that required to implement the intervention strategy and it is also necessary to assess the probability of the flooding time.

Relazione fra comunità macrobentoniche e morfodinamica nelle zone costiere dell’Alto Adriatico

Numerosi studi hanno messo in evidenza che la struttura delle comunità macrobentoniche delle spiagge sabbiose dipende da una serie di forzanti fisiche; queste ultime interagendo tra loro determinano la morfodinamica della spiagge stesse. Lo scopo di questo lavoro consiste nell’analisi dei popolamenti macrobentonici di due siti presenti lungo la costa emiliano - romagnola, che differiscono per caratteristiche morfodinamiche, grado di antropizzazione e modalità gestionali di difesa dall’erosione costiera. I siti oggetto di studio sono Lido Spina e Bellocchio; il primo è soggetto ad interventi di ripascimento periodici, mentre il secondo rappresenta un’opportunità rara, per lo studio degli effetti del retreat, in quanto è in forte erosione da molti anni ma, essendo inserito all’interno di una riserva naturale, non è sottoposto ad alcuna misura di gestione. Sono state analizzate le comunità macrobentoniche e le variabili abiotiche (mediana e classazione del sedimento, ampiezza della zona intertidale, pendenza della spiaggia, contenuto di sostanza organica totale presente nel sedimento e i principali parametri chimico-fisici). I risultati del presente studio hanno evidenziato un’elevata eterogeneità della struttura di comunità all’interno del sito di Bellocchio rispetto a Spina; inoltre i popolamenti presenti a Bellocchio mostrano una netta differenza tra i due livelli mareali. Per quanto riguarda i descrittori abiotici, i due siti differiscono per ampiezza della zona intertidale e pendenza della spiaggia; in particolare Lido Spina presenta una condizione di minore dissipatività, essendo caratterizzata da un profilo più ripido e una granulometria più grossolana rispetto a Bellocchio. Nel complesso le caratteristiche granulometriche (mediana e classazione) e il contenuto di materia organica rappresentano le variabili ambientali maggiormente responsabili delle differenze osservate tra i popolamenti macrobentonici analizzati. Al fine di valutare la resistenza dell’habitat intertidale agli eventi naturali di disturbo (storm surge e flooding), sono state effettuare delle simulazioni considerando lo scenario attuale (SLR=0), mediante un modello ibrido fuzzy naive Bayes. I risultati indicano una maggiore resistenza delle comunità presenti nel sito di Spina, in quanto non si hanno variazioni significative del numero medio di taxa e di individui; viceversa le simulazioni relative a Bellocchio mostrano una diminuzione del numero medio di taxa e aumento del numero medio di individui, sottolineando una maggiore vulnerabilità delle comunità macrobentoniche presenti in questo sito. L’inasprimento dei fenomeni estremi potrebbe quindi avere un effetto negativo sulla diversità della componente macrobentonica, soprattutto per gli ambienti di transizione già interessati da fenomeni erosivi, come nel caso di Bellocchio. La perdita di specie, che svolgono processi ecosistemici particolarmente importanti, come il riciclo di nutrienti, potrebbe favorire l’aumento di abbondanza di specie opportunistiche, l’insediamento di specie alloctone, con la conseguente alterazione, se non scomparsa delle principali funzioni ecologiche svolte da questi ecosistemi costieri.

Previsioni di stati ecosistemici dell'intertidale sabbioso del Nord Adriatico in risposta ad eventi meteorologici estremi

Il presente elaborato di tesi si inserisce nell’ambito del progetto europeo THESEUS (Innovative technologies for safer European coasts in a changing climate) fra i cui principali obiettivi c’è quello di fornire un’adeguata metodologia integrata per la pianificazione di strategie di difesa costiera sostenibili. Le zone costiere sono sempre più soggette agli impatti antropici, legati all’intensificazione dell’urbanizzazione, e agli effetti del global climate change, ed in particolare al conseguente sea level rise. Diventa quindi importante, in un’ottica di preservazione e di gestione, capire come gli ecosistemi costieri e i beni e servizi che essi forniscono risponderanno a questi cambiamenti ambientali. Fra questi, preponderanti sono quelli rappresentati dalle spiagge sabbiose. Al fine di valutare come differenti strategie di gestione possono influenzare il sistema spiaggia, è stata analizzata la riposta del comparto bentonico della zona intertidale di due differenti spiagge lungo la costa emiliano-romagnola. Lido di Spina è fortemente antropizzato e caratterizzato dalla presenza di infrastrutture balneari-turistiche permanenti. E’ soggetto, inoltre, a interventi di ripascimento annuali e di pulizia della spiaggia. Bellocchio, invece, è un sito naturale che presenta una spiaggia caratterizzata dall’arretramento della linea di costa causata dell’erosione, e non è soggetta a interventi di gestione finalizzati alla sua mitigazione. In questo studio è stata utilizzata la componente meiobentonica, generalmente trascurata, come indicatore chiave della vulnerabilità ecologica, mentre la zona intertidale sabbiosa è stata indagata in quanto reputata uno dei primi habitat costieri “recettore” degli eventi di flooding e degli interventi di gestione. Globalmente è stato possibile evidenziare differenze di struttura di comunità fra i due siti indagati, sottolineando come, anche questa componente sia in grado di far emergere i cambiamenti dovuti a differenti approcci di gestione delle coste sabbiose. Nella seconda parte del lavoro, invece, è stato testato un approccio metodologico innovativo, denominato “Fuzzy Bayes Ecological Model” (FBEM), sviluppato nell’ambito del progetto THESEUS. L’applicazione del FBEM in THESEUS è finalizzata alla simulazione delle risposte ecosistemiche ad eventi di flooding costiero ed al fenomeno del sea level rise. In questo elaborato, il modello è stato adottato al fine di descrivere eventuali cambiamenti dei popolamenti meiobentonici. Nello specifico, l’utilizzo del modello è servito per poter confrontare la situazione attuale relativa, quindi, allo scenario di sea level rise pari a zero, con quella ipotizzata dall’IPCC per il 2080 di sea level rise pari a 0,22 m, prendendo in considerazione otto tempi di ritorno di eventi simulati di flooding a intensità crescente. Dalle simulazioni emerge come il driver del danno ecologico sia l’onda frangente il cui effetto risulta, però, mitigato dal sea level rise. I popolamenti meiobentonici sono risultati dei buoni indicatori per la valutazione dei rischi connessi al flooding e al sea level rise, dimostrando così il loro possibile utilizzo come descrittori dei cambiamenti ecologici delle zone costiere. Per questo, lo studio ed il monitoraggio della dinamica e della struttura dei popolamenti meiobentonici può diventare un mezzo fondamentale per la comprensione delle funzionalità ecosistemiche delle spiagge sabbiose. E’ inoltre in grado di produrre alcune delle informazioni necessarie allo sviluppo dei piani di gestione integrata della fascia costiera in un ottica di conservazione di questi habitat costieri e dei servizi e beni da essi forniti.

Sviluppo di un approccio congiunto fuzzy-Bayesiano per l'analisi e la modellizzazione degli ecosistemi: applicazione ad ecosistemi marini costieri.

Nell’attuale contesto di aumento degli impatti antropici e di “Global Climate Change” emerge la necessità di comprenderne i possibili effetti di questi sugli ecosistemi inquadrati come fruitori di servizi e funzioni imprescindibili sui quali si basano intere tessiture economiche e sociali. Lo studio previsionale degli ecosistemi si scontra con l’elevata complessità di questi ultimi in luogo di una altrettanto elevata scarsità di osservazioni integrate. L’approccio modellistico appare il più adatto all’analisi delle dinamiche complesse degli ecosistemi ed alla contestualizzazione complessa di risultati sperimentali ed osservazioni empiriche. L’approccio riduzionista-deterministico solitamente utilizzato nell’implementazione di modelli non si è però sin qui dimostrato in grado di raggiungere i livelli di complessità più elevati all’interno della struttura eco sistemica. La componente che meglio descrive la complessità ecosistemica è quella biotica in virtù dell’elevata dipendenza dalle altre componenti e dalle loro interazioni. In questo lavoro di tesi viene proposto un approccio modellistico stocastico basato sull’utilizzo di un compilatore naive Bayes operante in ambiente fuzzy. L’utilizzo congiunto di logica fuzzy e approccio naive Bayes è utile al processa mento del livello di complessità e conseguentemente incertezza insito negli ecosistemi. I modelli generativi ottenuti, chiamati Fuzzy Bayesian Ecological Model(FBEM) appaiono in grado di modellizare gli stati eco sistemici in funzione dell’ elevato numero di interazioni che entrano in gioco nella determinazione degli stati degli ecosistemi. Modelli FBEM sono stati utilizzati per comprendere il rischio ambientale per habitat intertidale di spiagge sabbiose in caso di eventi di flooding costiero previsti nell’arco di tempo 2010-2100. L’applicazione è stata effettuata all’interno del progetto EU “Theseus” per il quale i modelli FBEM sono stati utilizzati anche per una simulazione a lungo termine e per il calcolo dei tipping point specifici dell’habitat secondo eventi di flooding di diversa intensità.

Theoretical and Experimental Analysis of micro-CHP Energy Systems

In the framework of the micro-CHP (Combined Heat and Power) energy systems and the Distributed Generation (GD) concept, an Integrated Energy System (IES) able to meet the energy and thermal requirements of specific users, using different types of fuel to feed several micro-CHP energy sources, with the integration of electric generators of renewable energy sources (RES), electrical and thermal storage systems and the control system was conceived and built. A 5 kWel Polymer Electrolyte Membrane Fuel Cell (PEMFC) has been studied. Using experimental data obtained from various measurement campaign, the electrical and CHP PEMFC system performance have been determinate. The analysis of the effect of the water management of the anodic exhaust at variable FC loads has been carried out, and the purge process programming logic was optimized, leading also to the determination of the optimal flooding times by varying the AC FC power delivered by the cell. Furthermore, the degradation mechanisms of the PEMFC system, in particular due to the flooding of the anodic side, have been assessed using an algorithm that considers the FC like a black box, and it is able to determine the amount of not-reacted H2 and, therefore, the causes which produce that. Using experimental data that cover a two-year time span, the ageing suffered by the FC system has been tested and analyzed.

Analysis and development of ecologically based approaches to coastal defense

Climate-change related impacts, notably coastal erosion, inundation and flooding from sea level rise and storms, will increase in the coming decades enhancing the risks for coastal populations. Further recourse to coastal armoring and other engineered defenses to address risk reduction will exacerbate threats to coastal ecosystems. Alternatively, protection services provided by healthy ecosystems is emerging as a key element in climate adaptation and disaster risk management. I examined two distinct approaches to coastal defense on the base of their ecological and ecosystem conservation values. First, I analyzed the role of coastal ecosystems in providing services for hazard risk reduction. The value in wave attenuation of coral reefs was quantitatively demonstrated using a meta-analysis approach. Results indicate that coral reefs can provide wave attenuation comparable to hard engineering artificial defenses and at lower costs. Conservation and restoration of existing coral reefs are cost-effective management options for disaster risk reduction. Second, I evaluated the possibility to enhance the ecological value of artificial coastal defense structures (CDS) as habitats for marine communities. I documented the suitability of CDS to support native, ecologically relevant, habitat-forming canopy algae exploring the feasibility of enhancing CDS ecological value by promoting the growth of desired species. Juveniles of Cystoseira barbata can be successfully transplanted at both natural and artificial habitats and not affected by lack of surrounding adult algal individuals nor by substratum orientation. Transplantation success was limited by biotic disturbance from macrograzers on CDS compared to natural habitats. Future work should explore the reasons behind the different ecological functioning of artificial and natural habitats unraveling the factors and mechanisms that cause it. The comprehension of the functioning of systems associated with artificial habitats is the key to allow environmental managers to identify proper mitigation options and to forecast the impact of alternative coastal development plans.

Flut und Hitze: Auswirkungen extremer Klimaereignisse auf die epigäische Arthropodenfauna (Araneae – Spinnen) ufernaher Lebensräume (Auen, Polder) des Inselrheins bei Mainz

Die vorliegende Arbeit ist ein Teil des Projektes Flut und Hitze des Kompetenzzentrums Überflutung an der Universität Mainz. Die Ziele dieser Untersuchung waren: Die Artzusammensetzung und Phänologien der Spinnengemeinschaften von Uferhabitaten bei Mainz (Rheinland-Pfalz, Deutschland) zu ermitteln, anhand des Artenspektrums die Folgen langjähriger Trockenheit und die Auswirkungen des Extremsommers 2003 zu beschreiben, Einflüsse von Überflutungen festzustellen und die Submersionstoleranzen ausgewählter Arten zu bestimmen. Insgesamt wurden 27783 Spinnen aus 179 Arten und 24 Familien bearbeitet. Die Untersuchung umfasste einen Hartholzauwald bei Ingelheim am Rhein, den Hochwasserschutzpolder Ingelheim, sowie Tiermaterial von vier weiteren Uferstandorten und drei Inselstandorten des Rheins bei Mainz. Die Beprobung der Hartholzaue mit Barberfallen und Stammeklektoren erfolgte von Mai 2005 bis Mai 2008. Im Polder wurden von Oktober 2006 bis Mai 2008 mit Barberfallen und einem Vakuumsauger gefangen. Die Proben der weiteren Standorte stammten aus Barberfallenfängen der Jahre 2000 bis einschließlich 2005. In der seit Winter 2002/2003 nicht mehr überfluteten und im Sommer stark austrocknenden Hartholzaue wurde eine als xerotolerant zu bezeichnende Spinnenfauna vorgefunden. Dies galt insbesondere für die sehr artenreiche Stammregion. Zu den dominierenden Spezies zählten: Diplostyla concolor (Boden), Clubiona pallidula und Textrix denticulata (beide Stamm). Der Polder Ingelheim wurde überwiegend von euryöken Freilandbewohnern besiedelt, dominant kamen Oedothorax apicatus und Pardosa agrestis vor. Das Tiermaterial der Ufer- und Inselstandorte wies deutliche Unterschiede in der Artenzusammensetzung im Bezug auf die Flutungsintensität auf. Nach dem Ausbleiben von Hochwässern und dem starken Austrocknen der Standorte im Sommer 2003 wurden hygrobionte Arten wie Allomengea vidua kaum mehr vorgefunden, während sich xerotolerante Spezies ausbreiteten. Darüber hinaus wurden die Submersionstoleranzen ausgewählter Spinnenarten im Labor ermittelt. Die gewonnenen Daten lassen Vermuten, dass die getesteten Spinnenspezies durchaus in der Lage sind, bei niedrigen Wassertemperaturen eine kurze Flut submers zu überstehen. Unter hohen Temperaturen besteht dagegen keine Submersionstoleranz.

Cascading events triggering industrial accidents: quantitative assessment of NaTech and domino scenarios

The so called cascading events, which lead to high-impact low-frequency scenarios are rising concern worldwide. A chain of events result in a major industrial accident with dreadful (and often unpredicted) consequences. Cascading events can be the result of the realization of an external threat, like a terrorist attack a natural disaster or of “domino effect”. During domino events the escalation of a primary accident is driven by the propagation of the primary event to nearby units, causing an overall increment of the accident severity and an increment of the risk associated to an industrial installation. Also natural disasters, like intense flooding, hurricanes, earthquake and lightning are found capable to enhance the risk of an industrial area, triggering loss of containment of hazardous materials and in major accidents. The scientific community usually refers to those accidents as “NaTechs”: natural events triggering industrial accidents. In this document, a state of the art of available approaches to the modelling, assessment, prevention and management of domino and NaTech events is described. On the other hand, the relevant work carried out during past studies still needs to be consolidated and completed, in order to be applicable in a real industrial framework. New methodologies, developed during my research activity, aimed at the quantitative assessment of domino and NaTech accidents are presented. The tools and methods provided within this very study had the aim to assist the progress toward a consolidated and universal methodology for the assessment and prevention of cascading events, contributing to enhance safety and sustainability of the chemical and process industry.

A Web GIS Decision Support System For Coastal Risk Assessment and Mitigation Planning

Coastal flooding poses serious threats to coastal areas around the world, billions of dollars in damage to property and infrastructure, and threatens the lives of millions of people. Therefore, disaster management and risk assessment aims at detecting vulnerability and capacities in order to reduce coastal flood disaster risk. In particular, non-specialized researchers, emergency management personnel, and land use planners require an accurate, inexpensive method to determine and map risk associated with storm surge events and long-term sea level rise associated with climate change. This study contributes to the spatially evaluation and mapping of social-economic-environmental vulnerability and risk at sub-national scale through the development of appropriate tools and methods successfully embedded in a Web-GIS Decision Support System. A new set of raster-based models were studied and developed in order to be easily implemented in the Web-GIS framework with the purpose to quickly assess and map flood hazards characteristics, damage and vulnerability in a Multi-criteria approach. The Web-GIS DSS is developed recurring to open source software and programming language and its main peculiarity is to be available and usable by coastal managers and land use planners without requiring high scientific background in hydraulic engineering. The effectiveness of the system in the coastal risk assessment is evaluated trough its application to a real case study.

The use of satellite remote sensing for flood risk management

Over the last decades the impact of natural disasters to the global environment is becoming more and more severe. The number of disasters has dramatically increased, as well as the cost to the global economy and the number of people affected. Among the natural disaster, flood catastrophes are considered to be the most costly, devastating, broad extent and frequent, because of the tremendous fatalities, injuries, property damage, economic and social disruption they cause to the humankind. In the last thirty years, the World has suffered from severe flooding and the huge impact of floods has caused hundreds of thousands of deaths, destruction of infrastructures, disruption of economic activity and the loss of property for worth billions of dollars. In this context, satellite remote sensing, along with Geographic Information Systems (GIS), has become a key tool in flood risk management analysis. Remote sensing for supporting various aspects of flood risk management was investigated in the present thesis. In particular, the research focused on the use of satellite images for flood mapping and monitoring, damage assessment and risk assessment. The contribution of satellite remote sensing for the delineation of flood prone zones, the identification of damaged areas and the development of hazard maps was explored referring to selected cases of study.

Vergleich der Carabidenpopulation im Gefolge von Flut und Trockenheit in ufernahen Lebensräumen des Rheins (Auwald, Polder)

Diese Arbeit war ein Teilprojekt des Kompetenzzentrums „Flut und Hitze“ der Johannes-Gutenberg-Universität Mainz. Das gesamte Projekt beinhaltete bereits Untersuchungen über mögliche Folgen des lokalen Klimawandels (Überflutung/Trockenheit) auf andere Tiergruppen (z.B. Collembolen, Arachniden, etc.). Mit Hilfe der Laufkäfer als Bioindikatoren sollten mögliche Tendenzen des Klimawandels, aufgrund von Überflutungen, bzw. dem Ausbleiben von Überflutungen, aufgezeigt werden. In diesem Zusammenhang erfolgte die phänologische Erfassung der Laufkäfer in drei Untersuchungsgebieten entlang des Rheins: ein geschütztes Auwaldfragment und ein Polder in Ingelheim sowie ein Polder in Worms. Über einen Zeitraum von 2-3 Jahren wurde, mittels klassischer Fangmethoden (Bodenfallen), die Laufkäferfauna kontinuierlich erfasst. Insgesamt konnten im Auwald Ingelheim 2861 Individuen aus 59 Arten gefangen werden, im Polder Ingelheim 16029 Individuen aus 96 Arten und im Polder Worms 6946 Individuen aus 72 Arten. Seit 2003 wurde das Auwaldfragment nicht mehr vollüberflutet, was die geringe Anzahl an gefundenen auetypischen Arten erklärte. Die Laufkäferfauna des Auwaldes zeigte zwar noch einen deutlich feuchtegeprägten Charakter, jedoch war der Druck der einwandernden eurytopen Offenlandarten aus der Umgebung enorm. Der Polder Ingelheim wurde 2006 fertiggestellt und direkt im Anschluss beprobt. Der Polderinnenraum wurde durch den Bau eines ökologischen Flutungskanals an die Dynamik des Rheins angeschlossen. Der tiefergelegte Innenraum zeigte eine deutlich feuchteliebende Laufkäferfauna. Die trockenen höher gelegenen Randbereiche wiesen im Gegensatz dazu eine deutliche Ruderalfauna auf. Der Polder in Worms wurde bereits direkt nach seiner Fertigstellung 2001 von der Arbeitsgruppe Prof. Dr. Seitz (Universität Mainz) beprobt. Die erneute Datenerhebung 2008 sollte mögliche Veränderungen in der Laufkäferfauna sowie eine mögliche Sukzession aufzeigen. Es zeigten sich deutliche Veränderungen der Laufkäfergemeinschaften an den Standorten sowie die Ausbildung verschiedener Mikrohabitate.