Tesis sobre el tema "Ecosystem risks"

Depuis sa création en 1849, Libreville a connu une urbanisation non planifiée et non coordonnée. Au fil des décennies, cette urbanisation anarchique s'accompagne de déséquilibres environnementaux et soumet les citadins à de nombreux risques écosystémiques. L'urbanisation anarchique, son univers de production et les risques écosystémiques engendrés sont l'objet de cette recherche. Des questions peu abordées au Gabon sont soulevées : comment, par qui et pourquoi l'urbanisation anarchique est-elle produite ? Que révèle cette forme de production de la ville ? Dans quelle mesure la production de l'urbanisation anarchique contribue-t-elle à l'accroissement des risques écosystémiques ? Les réponses sont formulées suivant quatre axes. Dans un premier axe les changements d'occupation des sols dans la ville ont été identifiés, caractérisés et analysés. Les outils de télédétection et SIG utilisés ont permis de produire des cartes d'occupation des sols et des cartes de risques. Un deuxième axe étudie les relations nature-société à Libreville, et met en évidence les perceptions de la ville et de la nature, tout en identifiant les bienfaits que tirent les populations de la nature, et les risques écosystémiques auxquels la population est exposée. Le processus d'urbanisation en cours à Libreville a été caractérisé et analysé dans un troisième axe. Ces deux derniers axes s'appuient sur l'enquête de terrain par entretiens semi-directifs, les récits de vie recueillis auprès des populations et des acteurs locaux. Dans le quatrième axe, un regard prospectif a été porté sur Libreville à l'aide des cartes de simulation de l'occupation des sols. Les résultats de cette recherche montrent une expansion rapide, importante et déstructurée de l'emprise urbaine de Libreville et ses environs, accompagnée d'une déforestation importante de la région, principalement au nord. La dynamique observée dans la ville est le résultat d'un cercle vicieux : occupation anarchique des sols, accès à la terre de gré à gré, spéculation foncière, absence de contrôle foncier par l'État et laisser-faire, etc. Ces résultats montrent une perception généralisée de la dégradation de la nature et des pratiques de conservation et de protection, tant des citadins que des décideurs, une réduction de la biodiversité et témoignent de conflits citadins-nature. La dégradation et l'importante déforestation des mangroves et la construction des maisons sont les principales causes avancées par les enquêtés. Ainsi, les changements d'occupation des sols, et les impacts sur la nature, conduisent à l'augmentation des risques écosystémiques d'inondation et d'érosion côtière, perçus différemment selon l'âge, la localisation, le statut professionnel, etc. L'érosion continentale est très peu perçue comme un risque ou un problème, en dépit des résultats cartographiques montrant des zones exposées. En tant que coproduction des populations et des acteurs locaux, les divers acteurs trouvent un intérêt à l'urbanisation non-contrôlée. Des routines structurent la coproduction de l'espace : des campements précaires, des routes et pistes ouvrent la voie à l'urbanisation et la déforestation, etc. Une absence de synergie, des conflits de compétences, une décentralisation insuffisante, une gabegie financière et une politique à outrance marquent également cette urbanisation anarchique. Dans un scénario de laisser-faire, la modélisation prospective de l'occupation des sols montre, une réduction importante de la végétation dense dans les espaces protégés. Dans un schéma de contrôle, en revanche, elle montre une conservation de la quasi-totalité des zones protégées. Ces situations, qui renseignent sur l'avenir de Libreville, posent des questions sur la gouvernance urbaine et environnementale au Gabon. Alors, est faite une tentative d'analyse des possibilités de changement en s'appuyant sur des modèles de villes en Afrique et dans le monde, tant sur les aspects urbains qu'environnementaux<br>Since its creation in 1849, Libreville has experienced unplanned and uncoordinated urbanisation. Over the decades, this anarchic urbanisation has been accompanied by environmental imbalances and has subjected city dwellers to numerous ecosystem risks. This research focuses on anarchic urbanisation, its production universe and the resulting ecosystem risks. Questions that are not often addressed in Gabon are raised: how, by whom and why is anarchic urbanisation produced? What does this form of urban production reveal? To what extent does the production of anarchic urbanisation contribute to the increase in ecosystem risks? The answers are formulated along four lines. In the first axis, land use changes in the city were identified, characterised and analysed. Remote sensing and GIS tools were used to produce land use maps and risk maps. A second axis studies nature-society relations in Libreville, and highlights the perceptions of the city and nature, while identifying the benefits that the population derives from nature, and the ecosystemic risks to which the population is exposed. The urbanisation process underway in Libreville was characterised and analysed in a third axis. These last two axes are based on fieldwork using semi-directive interviews and life stories collected from local populations and actors. In the fourth section, a prospective view of Libreville was taken using land-use simulation maps. The results of this research show a rapid, significant and unstructured expansion of the urban area of Libreville and its surroundings, accompanied by significant deforestation of the region, mainly in the north. The dynamics observed in the city are the result of a vicious circle: anarchic land occupation, access to land by mutual agreement, land speculation, lack of land control by the state and laissez-faire, etc. These results show a widespread perception of nature degradation and conservation and protection practices by both city dwellers and decision-makers, a reduction in biodiversity and evidence of city-nature conflicts. The degradation and extensive deforestation of mangroves and the construction of houses are the main causes put forward by the respondents. Thus, changes in land use and impacts on nature lead to an increase in the ecosystem risks of flooding and coastal erosion, which are perceived differently according to age, location, professional status, etc. Continental erosion is very little perceived as a risk or a problem, despite mapping results showing exposed areas. As a co-production of local populations and actors, the various actors find an interest in uncontrolled urbanisation. Routines structure the co-production of space: precarious settlements, roads and tracks pave the way for urbanisation and deforestation, etc. A lack of synergy, conflicts of competence, insufficient decentralisation, financial mismanagement and excessive politics also mark this anarchic urbanisation. In a laissez-faire scenario, prospective land-use modelling shows a significant reduction in dense vegetation in protected areas. In a control scenario, on the other hand, it shows a conservation of almost all the protected areas. These situations, which provide information on the future of Libreville, raise questions about urban and environmental governance in Gabon. An attempt is therefore made to analyse the possibilities for change based on models of cities in Africa and the world, both on urban and environmental aspects

The primary research problem addressed in this thesis is the development of a conceptual framework for a novel ecological economics risk measure called “ecosystem services value at risk” to guide sustainability, efficiency and fairness in the human use of natural ecosystems. Ecosystem services value at risk integrates ecosystem services valuation with financial value at risk to provide an estimate of a “worst likely loss” in ecosystem services under alternative policies. This new approach estimates the uncertainty around ecosystem services values from human activities. By framing the risk to ecosystem services in terms of loss, this risk measure conveys a more powerful message about the need to protect nature. The core elements of an ecosystem services value at risk framework are: ecosystem services valuation; total economic value; stochastic ecological resource use models; financial value at risk; intergenerational discounting; society’s time frame for evaluation; and decision rules. This research is multidisciplinary, drawing insights from ecological economics, finance, fisheries economics, ecological modeling and decision analysis. Ecosystem services value at risk is illustrated with marine examples, which are timely and critical. Marine ecosystems, which provide valuable and essential benefits to humankind, are being severely altered all over the world from overfishing, climate change, marine pollution and habitat destruction. The risk measure is shown to be meaningful by applying a stochastic Schaefer surplus production model to a well-studied marine example, Namibian hake. A case study of the collapsed Georges Bank yellowtail flounder further demonstrates its usefulness to marine policy evaluation. A simple risk measure based on the market values of catch provisioning services leads to selecting conservative harvest policies, ruling out high levels of fishing intensity. The non-market values of a second type of ecosystem service, the regulating services from conserved biomass, are next considered. Both values provide a distribution for a lower bound estimate of the ecosystem services value at risk for the marine ecosystem. Including regulating services allows even more precautionary strategies that favor conservation. The ecosystem services value at risk framework thus supports sustainability and ecosystem resilience, promising to help protect the flow of benefits from nature for current and future generations.

Drylands cover nearly half of the earth’s terrestrial surface and are home to unique ecosystems and vibrant cultures. Dryland communities face various challenges of living in the harsh and variable conditions presented by their environment and landscapes. These challenges are magnified in the arid landscapes of India, where agriculture is largely rain-fed and human and livestock population densities are some of the largest in the world. Communities and landscapes in arid India are exceptionally vulnerable due to intensifying dryland degradation, increasing rainfall variability along with climate change. This thesis contributes to a critical research area by developing and applying a methodological framework centred on ‘vulnerability’ for investigating dryland degradation in India’s arid landscapes. Dryland degradation is studied as a synthesis of the complex interactions between socio-ecological system functions within inherently dynamic environments. The empirical basis for the study is the use of mixed methods incorporating primary and secondary data, enriched by community perspectives. The study provides new insights through findings on the interactions between land use, land degradation, and climate risks. It addresses gaps in drylands research, especially in the development of a context specific vulnerability framework for drylands. It, furthermore, uses this framework to provide recommendations to confront dryland degradation while planning for effective adaptation. Overall, the analysis finds that the dominant narrative in India - of poor farmers in the Thar desert struggling to cope with drought, in need of protection from their natural environment – to be fundamentally misplaced. However, as their land becomes increasingly degraded and their surrounding climate less predictable, their socio-cultural systems and institutions become less resilient. As a result, arid zone farmers are now more likely to turn to strategies that aim for short-term solutions, which may only exacerbate vulnerability and land degradation in the longer term.

There is a need for models that produce results that are both timely and sufficiently accurate to be useful to policy makers. The minimum-data approach of Antle and Valdivia (2006) responds to this need by supplying a spatially explicit first order approximation that models ecosystem supply by producers. However, producers in developing nations often are observed to deviate from simple expected profit maximization. Risk is one possible explanation for this divergence. This study builds upon the minimum-data approach by allowing for risk averse producer preferences. The study presents a framework for translating relative risk aversion measurements into the parameters needed for the mean-standard deviation utility function. This study utilizes experimental and econometric measurements of risk aversion by other researchers to parameterize the model. Historic weather data are used with crop yield models to simulate temporal variation in crop yields. The model is used to simulate the supply of carbon sequestration in Machakos, Kenya. At low levels of risk, producers behave in a manner consistent with risk neutrality. However as risks and risk aversion levels increase, there is an increasing divergence from the behavior implied by expected profit maximization. The effects of varying the structure of risk preferences were also examined. This study finds that, consistent with the results in a number of other studies, the level of risk aversion is generally a more important factor in simulated behavior than the structure of risk preferences. This study also examines the effects of increasing the spatial variation of returns. As the spatial variation of returns increases, the predicted producer behavior converges on a fifty percent rate of adoption of the carbon sequestering system, regardless of other parameters. Overall, this study finds that - at levels of risk aversion measured in similar populations in developing nations - the inclusion of risk aversion in the model provides an explanation for why the observed behavior of producers appears to diverge from expected profit maximization.

The aim of this work is to develop a multidisciplinary approach to (i) understand the dynamics of freshwater-related ecosystem services (ES); (ii) quantify the conjoined effects of climate and land use change on these ES; (iii) evaluate the effectiveness of different management scenarios; and (iv) provide appropriate indicators to support the identification of proper practices to improve ES management at the local level. First, we reviewed the complex effects of climatic and non-climatic drivers on the supply and demand of freshwater ecosystem services. Based on the literature, we proposed a conceptual framework and a set of indicators for assessing the above-mentioned impacts due to global change, i.e. climate change and human activities. Then, we checked their applicability to the provisioning services of two well-known case studies, namely the Po River basin (Italy) and the Red River basin (Vietnam). Second, we developed an integrated modeling approach to assess the conjoined impacts of land use and climate changes on the potential ecosystem services (i.e. water yield and nutrients retention) until 2050. This integrated approach is applied to the Taro river basin in the context of the PROLINE CE project, which focused on the sustainable use of freshwater in an integrated land use management approach. Finally, we integrated Bayesian Networks in ecosystem service model which enables identification of risks of human interaction on ecosystem, trade-offs among ecosystem services, and evaluation of different management scenarios. The outcomes of this work could be a valuable support to identify and prioritize the best management practices for sustainable water use, balancing the tradeoffs among services.

In recent years, society has begun to take a new view of its relations with the surrounding environment, and in particular has become aware of the need to ensure the sustainability of the oceans and their biodiversity. This concerns have also moved the scientific community to include aspects of environmental science and engineering in their curricula. This thesis links both the causes and effects of maritime transport with the necessary protection of marine resources aiming to justify a specific proposal that would allow the right balance between the needs of maritime transportation and the desired environmental protection of the Strait of Gibraltar and the Gulf of Cadiz. Recent studies show that the model of human activity in this area is hardly sustainable in the terms in which has occurred to date and conclude that continuing with the current rate of growth of these activities would result in environmental problems leading to decreased levels of quality of life and a weakness of the productive sectors. It has also been demonstrated that the effects of chronic discharges in areas adjacent to the Strait of Gibraltar are more damaging than large spills even though limited in time, as occurred in the aftermath of the Prestige accident. Shipping is one of those human activities that have an ongoing impact on the marine environment and is capable of generating acute risks of serious environmental and economic consequences to the region. For these reasons, other Spanish waters enjoy some degree of protection against threats arising from shipping: the Mediterranean Sea is a Special Area under MARPOL Convention; the Cantabrian Sea and the north-western Atlantic waters are part of the Western European PSSA; and the Canary Islands were also designated as PSSA were several protective measures have been implemented. The designation of a Particularly Sensitive Sea Area (PSSA) represents a major advance in environmental protection that complements other existing conservation strategies. It is striking to note that despite the fact that the area subject to study supports one of the largest maritime traffic intensities of the planet and includes important spaces of environmental conservation - including UNESCO's Biosphere Reserves-, lacks an adequate level of protection to minimize the risks of marine pollution. In summary, this thesis studies the characteristics of the maritime area of the Strait of Gibraltar and the Gulf of Cadiz, as well as the levels of protection against the risks arising from shipping. A thorough analysis of the different options offered by international regulations to improve the aforementioned levels of protection leads to the conclusion that it would be appropriate to formally designate the area as a PSSA. Consequently, the dissertation postulates a detailed and definitive proposal for the designation of the PSSA STRAIT OF GIBRALTAR AND GULF OF CADIZ including various associated protective measures that could be implemented to improve safety of navigation, thus reducing the impact that maritime activities pose on the marine environment. The proposals put forward may also constitute a case study on how to combine science and engineering to achieve an environmental objective. In particular, Chapter 5 forms the basis for an eventual formulation of the proposed PSSA to the International Maritime Organization (IMO). Finally, the thesis provides lines of future research on further protection of the proposed PSSA. As a result, in addition to its value in the academic context, the work undertaken could materialize into concrete proposals that would contribute to the transfer of knowledge to the advantage of economic and social development through implementation of the academic research. This indeed contributes to the achievement of the UPC's own driven general strategies, as well as the enacted goals of the Campus of International Excellence of the Sea in the territorial context of the area covered by this thesis.<br>Esta tesis estudia las características del litoral y de las aguas marítimas de la zona del Estrecho de Gibraltar y Golfo de Cádiz, así como los niveles de protección frente a los riesgos derivados de la navegación y otras actividades marítimas en esa zona. Tras analizar detalladamente las diferentes opciones que ofrece la normativa internacional para mejorar los referidos niveles de protección, se concluye que resultaría adecuada la designación por parte de la Organización Marítima Internacional de esas aguas como Zona Marina Especialmente Sensible (ZMES) de acuerdo con las disposiciones del Convenio MARPOL. Consecuentemente, el trabajo personal de planteamiento de la tesis aporta una propuesta concreta para la designación de la ZMES del ESTRECHO DE GIBRALTAR Y GOLFO DE CÁDIZ que constituye el objeto principal de la tesis. Finalmente, a través de metodologías de selección de criterios, se diseña un sistema de ordenación de tráfico marítimo para la zona designada, que incluye distintas Medidas de Protección Asociadas que podrían implantarse para mejorar la eficiencia y los niveles de seguridad de la navegación reduciendo por tanto el impacto de las actividades marítimas sobre el medio marino

This work is a descriptive case study of deployment of the agile risk management with Jira into complex product development ecosystem. The context is a Development Team in Finland that is leading distributed product development for a small cell radio base station (RBS). The quality management requirements in the ISO 9001:2015 standard have been updated and the main impact is the deployment of the risk based thinking. The Development Team in Finland has gone through a transformation from release project driven development to continuous software development. This major change requires that development processes and development support processes are also updated. Focus is in the improvement of the risk management process, methods and tools. Rationale for risk management improvement is based on the findings in the internal quality audit and the management’s intent is also taken into account. The implementation contains a new risk management process, customized issue type for Jira tool, risk management hands on training and replacement of the old spreadsheet based risk management tools. The new process replaces two earlier processes making things simpler. The unified approach covers both normal risks in the product development and product security and privacy related risks. Agile product development emphasizes the empowerment of the cross-functional team. The results show that deployment of the agile risk management has shifted the risk management ownership to development teams instead of the release management function. The benefits of risk management for software industry and for the case study are included to motivate the use of the risk management in the daily operations<br>Tämä työ on kuvaileva tapaustutkimus ketterän riskienhallinnan käyttöönotosta Jiralla monimutkaisessa tuotekehitysekosysteemissä. Työ liittyy Suomessa olevaan kehitystiimiin, joka johtaa hajautettua tuotekehitystä piensolutukiasemalle. Laatujärjestelmän vaatimukset ovat päivitetty ISO 9001:2015 standardissa ja päivityksen suurin vaikutus on riskipohjaisen ajattelun käyttöönotto. Kehitystiimi Suomessa on läpikäynyt muutoksen julkaisuprojektiohjatusta kehityksestä jatkuvaan ohjelmistokehitykseen. Tämä suuri muutos vaati kehitys- ja kehityksen tukiprosessien päivittämistä. Huomio on riskienhallintaprosessin, menetelmien ja työkalujen parantamisessa. Perusteluina riskienhallinnan parantamiselle on havainnot sisäisestä laatujärjestelmän tarkastamisesta ja johdon tahtotila on myös huomioitu. Toteutus sisältää uuden riskienhallintaprosessin, räätälöidyt tehtävätyypit Jira työkaluun, riskienhallinnan käytännön perehdytyksen ja olemassa olevien taulukkolaskentapohjaisten riskienhallintatyökalujen korvaamisen. Uusi prosessi korvaa kaksi aikaisempaa prosessia yksinkertaistaen asioita. Yhdistetty lähestymistapa kattaa sekä normaalit riskit tuotekehityksessä, että tuotteen tietoturva. ja yksityisyysriskit. Ketterä tuotekehitys korostaa vaikutusvallan lisäämistä rajat ylittävissä tiimeissä. Tulosten perusteella ketterän riskienhallinnan käyttöönotto on siirtänyt riskien hallinnan omistajuuden kehitystiimeihin julkaisun hallintatoiminnosta. Riskienhallinnan hyödyt ohjelmistoteollisuudelle ja tapaustutkimukselle on sisällytetty motivoimaan riskienhallintaa päivittäisessä toiminnassa

The loss of large-bodied herbivores and/or top predators has been associated with large-scale changes in terrestrial, freshwater, and marine ecosystems around the world. Understanding the consequences of these declines has been hampered by a lack of studies in relatively pristine systems. To fill this gap, I investigated the dynamics of the relatively pristine seagrass ecosystem of Shark Bay, Australia. I began by examining the seagrass species distributions, stoichiometry, and patterns of nutrient limitation across the whole of Shark Bay. Large areas were N-limited, P-limited, or limited by factors other than nutrients. Phosphorus-limitation was centered in areas of restricted water exchange with the ocean. Nutrient content of seagrasses varied seasonally, but the strength of seasonal responses were species-specific. Using a cafeteria-style experiment, I found that fast-growing seagrass species, which had higher nutrient content experienced higher rates of herbivory than slow-growing species that are dominant in the bay but have low nutrient content. Although removal rates correlated well with nutrient content at a broad scale, within fast-growing species removal rates were not closely tied to N or P content. Using a combination of stable isotope analysis and animal borne video, I found that green turtles (Chelonia mydas) – one of the most abundant large-bodied herbivores in Shark Bay – appear to assimilate little energy from seagrasses at the population level. There was, however, evidence of individual specialization in turtle diets with some individuals foraging largely on seagrasses and others feeding primarily on macroalgae and gelatinous macroplankton. Finally, I used exclusion cages, to examine whether predation-sensitive habitat shifts by megagrazers (green turtles, dugongs) transmitted a behavior-mediated trophic cascade (BMTC) between sharks and seagrasses. In general, data were consistent with predictions of a behavior-mediated trophic cascade. Megaherbivore impacts on seagrasses were large only in the microhabitat where megaherbivores congregate to reduce predation risk. My study highlights the importance of large herbivores in structuring seagrass communities and, more generally, suggests that roving top predators likely are important in structuring communities - and possibly ecosystems - through non-consumptive pathways.

This thesis deals with the need to move towards a holistic, truly integrated and ecosystem-based beach management that allows a sustainable use of these systems within the socio-ecological paradigm. However, the scarcity of frameworks for such management has been identified as a major constraint. The goal of this thesis was to apply and develop a set of methodologies based on the introduction of the Ecosystem Approach principles to beach management. These tools would be part of the Ecosystem Based Management System (EMBS), a novel formal system of public good management developed for coastal and marine environments. The study was conducted along the Costa Brava, a coastal area highly affected by tourism that alternates urban and natural beaches. The work starts providing a brief description of major paradigms of environmental management, with special emphasis on beach management. It also discusses the situation in Spain and its differences with main European policies in this area. Results confirm the need of an integrated and holistic beach management based on "sources" and not only on "resources", and the urgency of developing tools that could be really implemented. The main contribution of this thesis is a methodological framework based on multi-hazards risk assessment, which allows managers to identify and prioritize the main hazards potentially disturbing the beach and affecting existing ecosystem services. Thus managers could adapt their strategies according to their priorities, visions and resources. This methodology was validated in S¿Abanell beach, where 7 hazards and 6 ecosystem services were identified. In this thesis, beaches have been analyzed as socio-ecological systems, emphasizing the social dimension of the system that is not always considered. In this dissertation the users¿ perceptions have been analyzed as a feedback of management measures, comparing them in two antagonistic settings: an urban (S¿Abanell) and a natural-protected beach (St Pere Pescador). Learning from previous measures, this feedback should improve the setting of management according to the characteristics of each beach, increasing its adaptability and avoiding its homogenisation. Natural attributes were a priority in the protected setting, while services were highlighted in the urban one. But significant differences were not as important as would be assumed a priori. This homogenization in users¿ perceptions could be due to the scarce information-education provided to users on the protected beach, to the management that not really emphasizes the natural attributes of this beach, and to the strong influence of the surroundings with a long tradition of mass tourism. Achieve an effective implementation of integrated management has been also cited as a critical need. In this sense, this study has addressed a key component by means of an institutional analysis, identifying responsible authorities and key officers in charge of beach management. For 8 beaches of the Costa Brava the assessment identified duplications and absences in the management of key processes underlying main beach functions. Likewise, it showed the great diversity and complexity of the current beach management structures of this zone. The results confirmed the prioritization of the recreational function of the beach, with beach management almost restricted to the summer season. Concerning management structures, even if the three major Spanish legal scales were clearly recognized, a myriad of layouts have been identified within Municipalities. Within the current model, different aspects of the same system are managed in isolation, by different authorities with different objectives. Hence, beach management is fragmented and based on responsibilities, hindering the eventual implementation of new management plans. Thus, this dissertation aims to contribute to the development of a pathway in order to achieve a holistic, truly integrated and ecosystem-based beach management model.<br>Esta tesis se enmarca en la urgente necesidad de avanzar hacia una gestión de playas holística, verdaderamente integrada y basada en los ecosistemas, permitiendo un uso sostenible de estos sistemas dentro del actual paradigma socio-ecológico. Uno de los principales obstáculos para ello ha sido la escasez de herramientas que puedan ser realmente implementadas. El objetivo de la tesis fue aplicar y desarrollar este tipo de metodologías introduciendo los principios del enfoque ecosistémico en la gestión de playas. Estas herramientas se integrarían en el Ecosystem Based Management System (EBMS), un sistema de gestión de bienes públicos actualmente en desarrollo para entornos costeros y marinos. El estudio se desarrolló en la Costa Brava, una región tradicionalmente turística que alterna playas urbanas y naturales. Este trabajo comienza describiendo la evolución de los principales paradigmas de la gestión ambiental, con énfasis en la gestión de playas. Se analiza además el caso de España y sus principales diferencias con las políticas europeas en esta materia. Los resultados confirman la necesidad de una gestión integrada basada en “las fuentes” y no sólo en “los recursos”, y de metodologías que puedan ser implementadas. La principal contribución de esta tesis es una metodología basada en la evaluación de riesgos por múltiples eventos, que permite identificar y priorizar las principales amenazas que pueden perturbar el sistema y los servicios ambientales que este brinda. Así los administradores podrían adaptar su gestión según sus prioridades, visiones y recursos. Esta metodología fue validada en la playa de S´Abanell, identificándose y cuantificándose siete eventos de riesgo y seis servicios ambientales. En esta tesis las playas han sido analizadas como sistemas socio-ecológicos, destacando la dimensión social del sistema que no siempre es considerada. Como feedback para la gestión, en este trabajo se analizaron y compararon las percepciones de los usuarios en dos playas antagónicas, una urbana (S´Abanell) y una natural protegida (St Pere Pescador). Este feedback permite aumentar la adaptabilidad de la gestión, ajustándola a las características de cada playa y evitando su homogeneización. Los atributos naturales fueron una prioridad en el escenario protegido, mientras que los servicios lo fueron en el urbano. Existieron diferencias significativas pero no fueron tan importantes como se hubiera asumido a priori. Esta homogeneización de las percepciones podría deberse a la escasa información/educación en la playa protegida, a una gestión en dicha playa que no destaca los atributos naturales como debería, y a una fuerte influencia de un entorno con gran tradición de turismo masivo. No lograr una efectiva implementación de la gestión integrada también ha sido un obstáculo, siendo esenciales las estructuras de gestión. En esta tesis se obtuvo un diagnóstico de las autoridades a cargo de la gestión de playas en 8 Municipios de la Costa Brava. Se realizó un análisis institucional analizando duplicaciones y ausencias en la gestión de los procesos que sustentan las principales funciones de la playa, así como la complejidad de sus estructuras. Los resultados confirmaron la priorización de la función recreativa, restringiendo la gestión de playas únicamente al verano y a la temporada de baño. Además de las tres principales estructuras jurídicas responsables de la gestión de playas en España, se identificaron una infinidad de diseños de estructura de gestión a nivel de Municipios. Bajo el actual modelo de gestión, aspectos de un mismo sistema se analizan por separado y en solitario, por diferentes autoridades con diferentes objetivos. La gestión esta fragmentada y basada en competencias, lo que obstaculiza la eventual aplicación de nuevos modelos integrados. De esta manera, esta tesis pretende contribuir al desarrollo de una vía que permita alcanzar un modelo de gestión de playas holístico, verdaderamente integrado y basado en los ecosistemas.

<p> This dissertation links human and ecological systems research to analyze resource management decisions for elodea, Alaska&rsquo;s first submerged aquatic invasive plant. The plant likely made it to Alaska through the aquarium trade. It was first discovered in urban parts of the state but is being introduced to remote water bodies by floatplanes and other pathways. Once introduced, elodea changes freshwater systems in ways that can threaten salmon and make floatplane destinations inaccessible. The analysis integrates multiple social and ecological data to estimate the potential future economic loss associated with its introduction to salmon fisheries and floatplane pilots. For estimating the effects on commercial sockeye fisheries, multiple methods of expert elicitation are used to quantify and validate expert opinion about elodea&rsquo;s ecological effects on salmon. These effects are believed to most likely be negative, but can in some instances be positive. Combined with market-based economic valuation, the approach accounts for the full range of potential ecological and economic effects. For analyzing the lost trip values to floatplane pilots, the analysis uses contingent valuation to estimate recreation demand for landing spots. A spatially-explicit model consisting of seven regions simulates elodea&rsquo;s spread across Alaska and its erratic population dynamics. This simulation model accounts for the change in region-specific colonization rates as elodea populations are eradicated. The most probable economic loss to commercial fisheries and recreational floatplane pilots is $97 million per year, with a 5% chance that combined losses exceed $456 million annually. The analysis describes how loss varies among stakeholders and regions, with more than half of statewide loss accruing to commercial sockeye salmon fisheries in Bristol Bay. Upfront management of all existing invasions is found to be the optimal management strategy for minimizing long-term loss. Even though the range of future economic loss is large, the certainty of long-term damage favors investments to eradicate current invasions and prevent new arrivals. The study serves as a step toward risk management aimed at protecting productive ecosystems of national and global significance.</p>

Ecological risk assessment (ERA) studies are important to assess environmental changes that have been caused by anthropogenic activities. These integration models show the estimation of adverse risk effects across the levels of biological organization potentially exposed to perturbation, including a better understanding of the ecosystems complexity. It is well known that the pesticide have severe environment effects contributing to biodiversity loss and trophic levels changes. In this context, the aim of this study was to evaluate the ecological risk assessment in pesticide contamination scenarios for aquatic and terrestrial compartments. To attempt it direct and indirect effects on individual response for different biological organization and for multi trophic interactions responses with ecosystems models were evaluated. Thus the environmental impacts in relation to losses and changes of the ecosystems functions and services were analyzed. For this purpose, a risk scenario was designed to compare the Ivermectin contamination exposure routes, via dermal (soil) and oral (food) on Eisenia fetida reproduction tests. An experimental approach was constructed to characterise the effects of the fungicide Scala® (Pyrimethanil) in spraying application comparing to homogenous soil application on a constructed soil multi-species test system. n experiment was performed to reported the effects of the fungicide Mythos® (Pyrimethanil) with terrestrial plant test followed by elutriate test with non-targets freshwater organisms and avoidance test with soil invertebrates and quantify the ecosystems services framework. A holistic higher tier fungicide risk assessment was done with terrestrial and aquatic responses and trophic levels with multitrophic interactions in ecosystem models and supplementary with individuals\' responses. The results obtained suggest that the analyzed reproduction parameters for earthworms were affected with the increase of ivermectin concentrations with statistical significant differences between the contamination exposure routes. The fungicide pyrimethanil has adverse effect on soil invertebrates\' response for the application and spatial distribution with the habitat preferences and foraging abilities has affected directly or indirectly by the fungicide toxicity. The impacts by the runoff and leaching pesticides into adjacent water bodies and surrounding soil showed changes in the organism\'s structure with changes and loss in the provisioning, regulatory and supporting services. The integrated holistic four-tiered fungicide risk assessment showed the possible impacts and the adverse effects on the terrestrial and aquatic organisms, ecosystems and processes in the simulate scenarios. From the results, it is possible to conclude that the experiments performed crossed the multiple aspects of contaminations and show the individuals to ecosystems responses approaches using the exposure routes of contamination, multi trophic interactions of experimental ecosystems models, behavioral, individual and some comparatives responses with aquatic and terrestrial compartments in risk assessment. Furthermore, this study are an important register for the deleterious effects and responses to impacts of pesticides, prompting the possible environmental losses and changes of the ecosystems functions and services in disturbances areas.<br>Os estudos de avaliação de risco ecológico consistem em avaliar os riscos ecológicos ocasionados pelas diversas atividades antropogênicas a um determinado sistema. Essa abordagem de integração reporta a estimativa dos efeitos de risco adverso através dos níveis de organização biológica potencialmente expostos a pertubação, incluindo assim uma melhor compreensão da complexidade dos ecossistemas. É bem conhecido que os pesticidas possuem efeitos nocivos ao meio ambiente, contribuindo para a perda de biodiversidade e mudanças nos níveis tróficos. A partir dessa análise, o objetivo geral desse estudo foi uma avaliação de risco ecológico em cenários de contaminação por pesticidas em relação aos compartimentos terrestres e aquáticos. Para tanto, foram avaliados os efeitos diretos e indiretos sobre as respostas individuais para diferentes níveis de organização biológica e para as interações multitróficas através de modelos ecossistêmicos. Assim, foram analisados os impactos ambientais em relação as perdas e mudanças das funções e serviços dos ecossistemas. Para esse propósito, foram desenvolvidos cenários de risco em relação as rotas de exposição do antiparasitário Ivermectin para a minhoca Eisenia fetida em relação a testes de reprodução, através da via dermal (solo) e oral (comida). Foi construída uma abordagem experimental para caracterizar os efeitos do fungicida Scala® (Pyrimethanil), comparando a aplicação através de pulverização por spray com a aplicação homogênea no solo em um sistema terrestre multiespécies. Experimentos foram realizados para reportar os efeitos do fungicida Mythos® (Pyrimethanil) em plantas terrestres alvo, seguidos por teste com elutriato com organismos de água doce não-alvo e testes de fuga com invertebrados terrestres não-alvo e uma quantificação dos serviços ecossistêmicos. Foi realizada uma avaliação de risco holística do fungicida pyrimethanil com respostas dos organismos terrestres e aquáticos e das interações tróficas através dos modelos ecossistêmicos e complementados com respostas individuais. Os resultados obtidos sugerem que os parâmetros de reprodução para as minhocas foram afetados com o aumento das concentrações de ivermectina com diferenças estatísticas significativas entre as rotas de exposição a contaminação. O fungicida pyrimethanil mostrou efeitos adversos sobre os invertebrados terrestres para as aplicações do pesticida e para a distribuição espacial, sendo as preferências de habitat e habilidade de forageio direta ou indiretamente afetadas pela toxicidade do fungicida. Os possíveis impactos do runoff e lixiviação nos corpos de água e solos adjacentes mostram mudanças na estrutura da comunidade com mudanças e perdas nos serviços ecossistêmicos de provisão, regulação e suporte. A avaliação de risco holística mostrou os impactos e efeitos adversos sobre os organismos terrestres e aquáticos, ecossistemas e processos nos diferentes cenários de simulação. Ao analisar os dados obtidos é possível concluir que os experimentos realizados permeiam os múltiplos aspectos da contaminação por pesticidas, mostrando respostas de indivíduos a ecossistemas através das rotas de exposição da contaminação, interações multitróficas a partir dos experimentos de modelos ecossistêmicos, respostas individuais, comportamentais e comparativas com os sistemas terrestres e aquáticos em avaliações de risco ecológico. Portanto, esse estudo se apresenta como um importante registro dos efeitos deletérios e das respostas dos impactos por pesticidas, levando a possíveis perdas e mudanças das funções e serviços ecossistêmicos em áreas com distúrbios.

Risk assessment process is complex because it requires a multidisciplinary approach. In official European procedures, risk is assessed on standardised scenarios, where the territory, at different scale levels is described without taking into account the spatial variability of parameters. These approaches represent a powerful tool to characterize potential risk, anyway results obtained are not representative of actual site-specific conditions. The aim of this research was to analyse the main critical issues of agrochemicals risk assessment in terrestrial ecosystems. Different steps of agrochemicals risk assessment were considered and evaluated coupling field studies with predictive approaches. Different scale levels of risk assessment, with particular attention on exposure evaluation, were considered. Risk for pollinators was selected as a specific case of study and a procedure to assess exposure and risk for these organisms was developed.

Natural ecosystems like forests, wetlands and coastal habitats are hypothesized to support disaster risk reduction by decreasing the exposure of communities to hazards such as floods, landslides and storm surge. Forest cover loss is thought to increase flood risk and is seen as a primary driver of soil erosion and consequent siltation of irrigation channels and agricultural fields. While there is a growing body of evidence in support of the role of ecosystem processes in providing these hazard mitigation services much of it is site specific, and gaps remain in our understanding of the specific contexts, type of hazards and scenarios in which forest ecosystems play this role. This study contributes new knowledge to this research gap by investigating the question of how smallholder farmers in Madagascar exposed to extreme weather hazards perceive the importance of tropical dry deciduous forests in regulating hazard impacts and supporting agricultural production. In doing so, this thesis first evaluates the evolving trajectories of change in system variables including various provisioning ecosystem services, biophysical, economic and governance indicators, and human wellbeing outcomes during Madagascar’s recent history to provide context and identify patterns at the national scale. It then investigates the problem at the local, sub-catchment scale in a case study setting through household surveys, focus groups and key informant interviews in two communities with opposing forest cover trajectories in northwest Madagascar. This combined methodological approach allows for the linking of local vulnerability to wider system dynamics. The first set of findings demonstrates that the broader systems dynamics show signs of trade-off between increasing crop production, deteriorating natural environment and decreasing human wellbeing, which together with an evident decrease in the level of connectivity between key parameters reflect conditions associated with stagnation and poverty traps. Case study results show a vulnerable smallholder farming population, typically exposed to a set of six hazard impact types during extreme weather events. The type of hazards experienced influences the perception of whether or not forests provide hazard impact mitigation benefits and this is one of thesis’ original contributions to knowledge. Another core finding confirms the importance of tropical dry forests to the lives of smallholder farmers through food and raw materials, and provides new insights on the positive view held by a majority of the participants of hazard mitigation services provided by forest fragments, while also finding that only the income generating services of forest based tourism and honey production predict participation in forest management. This study integrates two normally distinct areas of research – hazard mitigation and forest ecosystem services - to provide new insights on the relevance of forest cover and management to agricultural risk reduction in smallholder, forest-edge farm communities, contributing new knowledge with implications for both forest management and rural development policies.

Doutoramento em Engenharia do Ambiente - Instituto Superior de Agronomia<br>In freshwater ecosystems associated with agricultural areas, organisms are exposed to a multitude of toxicologically and structurally distinct pesticides in concentrations that may fluctuate over time. However, the environmental risks of chemicals are traditionally evaluated and regulated on the basis of single substance. Understanding and improving the link between effects and exposure assessment is an important step in the current challenges of risk assessment in order to increase its ecological relevance. To this end, integrated approaches of different hierarchical levels of complexity and ecological realism have been developed and applied, including: exposure modelling, laboratory testing with individual organisms, species sensitivity distribution, ecosystem models and assessment of aquatic community interactions to evaluate the effects of realistic pesticide combinations on water bodies associated with rice, tomato and maize typical agroecosystems of Mediterranean conditions. Contributing to the overall knowledge of the adequacy of the prospective risk assessment and demonstrating that pesticide risk may be underestimated during the actual registration procedure. The data generated in the present study contributed to the derivation of optimized programs of measures under the scope of European legislation; the identification of sites with the highest expected impacts of pesticide mixtures; the evaluation of the major pesticide compounds that contributed mostly to the identified aquatic risks. Furthermore contribute to a deeper knowledge and unravel the effects of co-occurring chemicals, environmental and biological stressors in aquatic ecosystems considering the effects of biotic and abiotic interactions at community and ecosystem levels. The results contribute to reducing the risks of pesticides in freshwater<br>N/A

The Best PhD Thesis in the Faculties of Dentistry, Engineering, Medicine and Science (University of Hong Kong), Li Ka Shing Prize,2007-2008<br>published_or_final_version<br>Biological Sciences<br>Master<br>Master of Philosophy

As outsourcing continues to grow in large global organisations, governance and risk management of the related outsourcing ecosystem is evolving as a strategic Board-level activity, driving competitive advantage and value-creation, in addition to value-protection. Amidst this growth and evolution, the outsourcing of Information Technology (IT) and IT-enabled Business Process Outsourcing (BPO) continues to mature into a broader category referred to by contemporary researchers as "business services" including almost every service that can be delivered by third parties, often enabled by digitisation and technology. Through such strategic initiatives, focused on creating inimitable competitive advantage and organisational value, organisations have increased their levels of dependence on outsourcing, exposing themselves to newer risks amid shifting business environments. But despite these developments, there has been limited research on the ability of organisations to manage risks around outsourcing with a dynamic mind-set to create and protect value for organisations. Instead, most research continues to focus exclusively on preventing "bad things happening". The first part of the research establishes the context by providing a forward-looking multi-disciplinary view on strategic risk and governance related to outsourcing. This is followed by gaining an understanding of how and why large global organisations are broadening their perspective and enhancing maturity over governance and risk-management around their outsourcing ecosystem, including capabilities that they must develop to emerge as astute decision-makers, using industry-specific case studies. The second part of the research uses primary data to capture the overall progress made in achieving this transformation and implementation challenges. This thesis contributes to the growing body of outsourcing literature by focusing on governance from a novel "outsourcing ecosystem" perspective. It also makes practical contributions by identifying and addressing implementation challenges relevant to this transformational thinking, together with a 2x2 framework, which hold relevance for organisations operating with a significant outsourcing ecosystem and their leadership.

A wide range of ecological communities ranging from polar terrestrial to tropical marine environments are affectedby global climate change. Over the last century, atmospheric temperature has increased by an average of 0. 60 C andis expected to rise by 1.1- 6.40C over the next 100 years. This rising temperature has increased the intensity andfrequency of weather extremes due to which a large number of species are facing risk of extinction. Studies haveshown that species existing on lower latitude are more sensitive to temperature variability compared to speciesexisting on higher latitude but temperature is increasing rapidly in higher latitude compare to lower latitude. Thisuneven distribution of temperature sensitive species and warming rate has highlighted the need for combined studiesof temperature variability and sensitiveness of species to predict how the ecosystems will respond to increasinglyvariable climate. Using a generalized Rosenzweig-MacArthur model, I explored how temperature variability andsensitivity of species will affect the extinction risks of species and how the connectance and species-richness ofecological communities will govern this response. This study showed that the risk of extinction of species mostlydepends on their sensitivity to temperature deviation from the optimum value and level of temperature variability.Among these two, sensitivity of species to temperature deviation was most prominent factor affecting extinction risk.In this study, connectance did not show any effect on mean extinction risk and time taken by a certain proportion ofspecies to reach pre-defined extinction thresholds. But, species-richness showed some effect on mean extinction riskof species. It was found that risk of extinction of species in species-rich communities was higher compared tospecies-poor communities. Species-rich communities also took shorter time before they lost 1/6 of the species. Thepresent study also suggests a possible tipping point due to increasing temperature variability in near future. In furtherstudies, different sensitivity of species at different trophic levels and the possible evolution of sensitivity of speciesshould also be consider while predicting how ecological communities will respond to changing climate in the longrun.

The level of alteration in response to the same level of exposure can vary greatly among different ecosystems: in particular, effects provoked by chemicals are not only relying on their “absolute toxicity” and on their concentration, but also on the ecological vulnerability of the system. Vulnerability is often overlooked in current risk assessment procedure, but its knowledge is pivotal in site-specific studies, where the object of the protection is shifted from a generic scenario to a real ecological system. The study of ecological vulnerability confirms that risk assessment, as becoming site-specific, needs more ecological knowledge. In this path, the use of ecological and biological traits of organisms has proven to be a promising approach to evaluate the ecological vulnerability at different level of biological organization. In this work the issue of the ecological vulnerability has been considered from several different perspectives, using multiples methodologies and working at completely different scales. The leading thread is to show how an ecologically based approach can enhance our understanding of environmental processes and thus improving risk assessment methodologies.

The traditional procedures for the ecotoxicological risk assessment are general, schematic and simplified and, for these reason, they are powerful tools for regulation purposes. Anyway, they don't take into account the actual consequences on natural communities, the interactions among populations within the community or the indirect effects of a contamination. The need of more "ecological realism" into them is thus felt. Recently, the application of the vulnerability concept, instead of sensitivity, and the use of biological characteristics (traits) of organisms for predicting it represent steps towards the introduction of more ecological realism in ecotoxicology. In the present work the traditional ecotoxicological procedures were used in different compartments in the same area, considering the stress given by plant protection products. Then, based on the previous step, some innovative aspects were applied on the soil compartment. Natural communities were investigated for assessing the actual consequences of the stress and possible indirect effects on the food web. The recent trait-based and vulnerability approaches were applied and the results compared each other. A vulnerability analysis procedure to a mixture of plant protection products for soil community was also developed.

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia<br>Forests are a key element in the Portuguese landscape. Moreover, fire hazard is a central challenge at national context. How can appropriate management potentially change fire behaviour, fire damage and the difficulty of fire suppression? What are the causal relationships between fire proneness, stand structure and forest stand composition? The common objective of the doctoral research among the five studies is to address the above issues based on principles of creating fire-resistant forests, underlying factors and implications for active forest management, while sustaining effective fire prevention levels. The ultimate goal is to provide forest managers and policy makers with tools to support their decisions, and more effectively align management policies, plans, and practices across fire-prone landscapes. The first research phase aims, across a range of scales from the individual tree to the stand level, respectively: (i) modelling the annual probability of wildfire occurrence of pure and even-aged eucalypt stands; (ii) developing a shrub biomass accumulation model, and (iii) a post-fire mortality model at stand level and the individual tree survival probability to mitigate damage in any forest stand structure. The second phase introduces fire behavior modeling coupled with common stand variables as a tool to (iv) assess potential crown fire occurrence through stand structure/stand composition, and (v) draw guidelines that express the difficulty of fire suppression in those fire-prone forest stands. The accuracy of the research findings can provide an interesting insight to support hazard-reduction silvicultural practices in Portuguese ecosystems

Les interactions entre aquaculture et pêche captive, et la viabilité comme approche de gestion du risque dans l'exploitation des écosystèmes<br>The world of fisheries is complex, dynamic and contested. At the core of fishery management lie technical challenges but also fundamental socioeconomic issues such as valuation and ownership. So far, as for other natural resources, fisheries resources have been largely over exploited and alarms from the scientific community on rapidly declining stocks and species disappearance have been repeatedly published. In what follows, I first strive to explain the repeated failures to manage fisheries in a sustainable way. In this perspective, I overview existing management instruments and the weaknesses of fisheries governance. Next, I raise the main challenges faced by the aquaculture industry to take over on capture fisheries, as a sustainable source of food security. This leads us to an introduction to the two first chapters of this dissertation, which focuses on the economic and ecological impacts of the expansion of aquaculture, and its implications for the capture fishery sector. Finally, I expose the complexity of managing harvested ecosystems under uncertainty, in practice. Thus, I present the third chapter of this dissertation which puts forward a theoretical management framework grounded in viability theory to deals with risk, ecosystem dynamics and conflicting sustainability objectives. In particular, I examine the different analytical possibilities provided by this framework to handle uncertain dynamics

Ecological Risk Assessment (ERA) is a process undertaken for estimating the environmental harms caused by human activities. The assessment is based on three components: effect assessment, exposure assessment, and risk characterisation. The latter is a combination of the former two. Various methodologies can be used for performing ERA, which can be categorised into deterministic and probabilistic. Probabilistic techniques have been at the focus of research the last years, due to their elaborated character and the possibilities they offer for more refined risk assessments. Despite their obvious advantages, probabilistic techniques present also disadvantages and challenges that need to be tackled. In the thesis, the possibility of exploring further the concept of Probabilistic Ecological Risk Assessment (PERA) is addressed. The main motivation of the thesis is identified in the effort to combine various well known concepts and methods for Ecological Risk Assessment, while enhancing them with new features and functionalities to serve the current needs of Risk Assessors. Therefore, providing a complete software package that allows performing efficient Propabilistic ERA (PERA) and offers related functionalities, all gathered in one place. The proposed software is developed as part of the research project AMORE (funded by the National French Research Academy – ANR). A proposal for a Decision Support System (DSS), named AMORE DSS, supporting Probabilistic ERA is described in detail and validated through the application of the proposed DSS to a case study for assessing the effects and risks posed by the presence of cyanide in a river in north-western France. The AMORE DSS aims at allowing efficient Probabilistic ERA and tackles issues related with PERA and the concept of weighted Species Sensitivity Distributions (SSWD) such as the handling of uncertainty in PERA, the production of reliable SSWD graphs and the assessment of the quality of ecotoxicological data. The theoretical section of the thesis is split into two main parts. In the first, the concept of Ecological Risk Assessment is introduced and the principal methods of interest are described. It is followed by the presentation of the concepts of Multi-Criteria Decision Analysis (MCDA) and Decision Support Systems (DSS), which are important aspects of the developed research. The methodological developments of the thesis are based on a proposal for the estimation of the reliability and relevance of ecotoxicological data used in ERA, which is presented in detail and evaluated. The proposed methodology is based on Multi-Criteria Decision Analysis and allows the assessment of ecotoxicological data on the basis of a fixed set of criteria and mathematically stable and robust aggregation techniques. Therefore, the methodology suggests the production of reliable weighted Species Sensitivity Distributions, a vital component of the probabilistic ERA and the calculation of risk probabilities. The proposal allows incorporating in the risk assessment the knowledge gathered from an expert panel and gives significant strength to the risk assessors for the performed assessments, through the use of previously not widely available information and expertise. The proposed DSS is built on the three components (exposure, effects, risk) of ERA and provides a complete set of functionalities to the risk assessors, enhanced with unique features. The thesis describes in detail the development of the software and the functionalities of each of its modules. The Exposure Assessment module aims at providing to the Decision Maker/Risk Assessor a collection of tools for the statistical analysis of environmental exposure data, through the concept of Predicted Environmental Concentration. The Effect Assessment module is based on the concept of weighted Species Sensitivity Distributions (SSWD) and incorporates the proposed methodology for the assessment of the reliability and relevance of ecotoxicological data. The Risk Assessment module is based on the concept of Potentially Affected Fraction (PAF) and aims at synthesising the results of the previous two modules for the estimation of risks, in an efficient and easy to present way. The last part of the thesis is dedicated to the application of the DSS to a real life case study. A Risk Assessment process is performed for estimating the sensitivity of species to the presence of Cyanide (CN) in the environment, for estimating Environmental Quality Criteria (EQC) for the assessed case and for estimating the level of risk posed from Cyanide at the ecosystem. The assessed area is the Selune rivershed in the Manche department of the lower Normandy region in France, where four sampling stations have been identified with records of Cyanide presence for the period 2005-2014. Regarding the ecotoxicological data of the case study, 26 scientific articles on cyanide toxicity, published in the period 1965-2011, have been analysed for the extraction and assessment of 46 toxicological endpoints for the aquatic environment. The case study is firstly based on all the available ecotoxicological data and secondly based on data split per taxonomic groups (i.e vertebrates, invertebrates) and trophic levels (i.e. primary producers, primary/secondary consumers). Specifically, six (6) sets of SSWD graphs are produced (i.e. All data, Vertebrates, Invertebrates, Primary producers, Primary consumers, Secondary consumers) with the use of two weighting options: (i) the weighting coefficients that are produced with the application of the MCDA based methodology and (ii) equal weighting coefficients for all the data. A comprehensive comparison of the two types of SSWD is performed and discussed in detail for the identification of the appropriateness of the fitting of the SSD curves to the experimental data. Hazardous concentrations (HCx) are estimated and presented for all the taxonomic groups and trophic levels. In addition, in combination with the results of the statistical analysis of the environmental exposure data, the risk is estimated for the assessed stations in the case study area. The results of the case study show that the primary producers are found to be the most sensitive trophic level while Invertebrates are more sensitive as a taxonomic group for low cyanide concentrations and Vertebrates are more sensitive for higher concentrations. Regarding the calculated risk indices, station 3 (L’Yvrande) of the Manche region is the area with the higher estimated risk. The performed application of the DSS in the cyanide case study demonstrates a complete probabilistic Ecological Risk Assessment process with the use of Species Sensitivity Distributions and the utilisation of Multi-Criteria Decision Analysis. The case study, alongside with the validation of the developed DSS, demonstrates the performance of the proposed MCDA-based WoE framework for the analysis of ecotoxicological data, based on three distinctive Lines of Evidence (Experimental Reliability, Statistical Reliability, Biological Relevance). The framework and the related MCDA methodology constitute an innovative development in the field of quantitative ecotoxicological data assessment frameworks. Furthermore, a robust performance of the DSS has been identified, which allows potential for adoption within the risk assessment research fields.The thesis is concluded with future considerations for the developed DSS, which could provide interesting functionalities and extensions of the capabilities of the software.

The thesis is related with the development of a fully functional, modular Decision Support System (DSS) for performing Probabilistic Ecological Risk Assessment (PERA) of pollutants in aquatic environments. The Decision Support System is a 3‐module software, which integrates the use of Multi‐Criteria Decision Analysis (MCDA) methods for the quantitative assessment of the reliability and relevance of ecotoxicological data. Ecotoxicological data are vital components of the Ecological Risk Assessment processes and specifically the Effect assessment part. A MCDA based methodology (i.e. from the definition of the conceptual framework to the software implementation in collaboration with an experienced programmer) has been fully developed for the assessment of ecotoxicological data, which are used for the creation of weighted Species Sensitivity Distribution (SSWD) graphs. The innovative MCDA based methodology allows the assessment of ecotoxicological data based on a set of 57 distinctive criteria and gives the possibility to researchers to classify and rank ecotoxicological data, based on their various characteristics. As part of the research project, a case study application has been performed for the analysis of the ecological risk from the presence of cyanide in the Sélune watershed, at the Manche region of the Lower Normandy in the north‐west part of France. Environmental exposure data of cyanide (CN) have been collected from the Water Agency of ‘Seine‐Normandie’ and used in the Exposure Assessment module, while ecotoxicological data for cyanide gathered from peer‐reviewed publications have been analysed with the use of the proposed MCDA based methodology, in the Effect Assessment module. The ecological risk assessment process was concluded with the calculation of the risk indices in the last module of the DSS.

Els boscos proveeixen d’una àmplia varietat de serveis ecosistèmics (SE). Entendre com i per què aquests SE es distribueixen en el paisatge és essencial per dotar a les polítiques d’informació per protegir, millorar i restaurar aquests ecosistemes. A més, l’efectivitat de les Àrees Protegides (AP) en el manteniment dels SE i la biodiversitat encara no està clara, i els boscos estan cada vegada més sotmesos a la pressió del canvi climàtic, amb canvis en el règim de pertorbacions (com ara els incendis). Predir on aquestes pertorbacions tindran lloc en el futur i fins a quin punt els SE dels boscos s’hi veuran afectats són reptes fonamentals en la recerca. L’objectiu general d’aquesta tesi és analitzar la distribució espacial dels SE als boscos, la seva rellevància en la conservació i la seva vulnerabilitat i risc enfront pertorbacions del canvi climàtic, especialment els incendis forestals. Per això, 1) hem analitzat la distribució espacial dels estocs de carboni i la biodiversitat, així com la relació entre ells i les seves causes, en boscos de dues regions i cinc subclimes; 2) hem determinat el rol de les AP en la preservació dels SE i la biodiversitat a Catalunya; 3) hem desenvolupat un marc conceptual per avaluar la vulnerabilitat dels boscos i el seu risc de pèrdua de SE; i 4) hem avaluat els patrons espacials i les causes de la vulnerabilitat dels boscos a incendis i el risc associat de pèrdua de SE a Catalunya. La relació entre els estocs de carboni i la biodiversitat és en general positiva, amb valors més elevats al nord d’Espanya i al sud del Québec. Valors de densitat i diversitat estructural elevats han afavorit al mateix temps els estocs de carboni, la biodiversitat d’arbres i la biodiversitat global. Respecte a les AP, hem trobat més estocs de carboni, cobertura d’hàbitats d’interès comunitari, hàbitats prioritaris i llocs d’interès geològic a l’interior de les AP que a les seves àrees d’influència (o buffer zones), però cap dels indicadors de biodiversitat (riquesa d’arbres i d’aus) ha mostrat diferències entre les AP i les àrees d’influència. Hem proposat un marc conceptual per avaluar la vulnerabilitat dels boscos i el risc de pèrdua de SE, basat en els components d’exposició, magnitud de la pertorbació, susceptibilitat i manca de capacitat adaptativa. Finalment, hem aplicat aquest marc general als incendis forestals de Catalunya. Els resultats han mostrat que la magnitud de la pertorbació és el component més important que defineix el risc de pèrdua de SE degut a incendis. El tipus funcional de bosc - especialment les coníferes no Mediterrànies que tenen poca capacitat adaptativa - és el factor més important sota condicions extremes. L’augment de risc més gran s’ha trobat en boscos relativament humits que actualment tenen un risc baix, situació que segons les tendències climàtiques actuals passarà a ser més comuna en un futur. En general, aquesta tesi ha augmentat l’evidència científica de la relació positiva entre els estocs de carboni i la biodiversitat en cinc subclimes. També ha mostrat que la conservació a Catalunya només és efectiva en el manteniment d’alguns dels SE i variables de conservació considerades. També ha contribuït amb un marc conceptual innovador sobre la vulnerabilitat dels boscos i el risc de pèrdua de SE degut a pertorbacions del canvi climàtic, assentant les bases per avaluar la vulnerabilitat i el risc d’una manera operativa i sistemàtica. L’aplicació d’aquest marc conceptual als incendis forestals ha mostrat implicacions rellevants en el risc de pèrdua de SE, fet que podria contribuir en el desenvolupament de polítiques futures mitjançant l’anticipació del risc, i ser una guia per la gestió forestal eficient.<br>Los bosques proveen una amplia variedad de servicios ecosistémicos (SE). Entender cómo y por qué estos SE se distribuyen en el paisaje es esencial para proteger, mejorar y restaurar estos ecosistemas. Además, la efectividad de las Áreas Protegidas (AP) en el mantenimiento de los SE y la biodiversidad aún no está del todo clara, y los bosques están cada vez más sometidos a la presión del cambio climático, con cambios en el régimen de perturbaciones (como incendios). Predecir en qué lugares estas perturbaciones se darán en un futuro y hasta qué punto los SE se verán afectados son retos fundamentales de investigación. El objetivo general de esta tesis es analizar la distribución espacial de los SE de los bosques, su relevancia en la conservación y su vulnerabilidad y riesgo frente a perturbaciones del cambio climático, especialmente los incendios forestales. Para cumplir este objetivo, 1) hemos analizado la distribución espacial de los stocks de carbono y la biodiversidad en los bosques, así como la relación entre ellos y sus causas, en dos regiones y cinco subclimas; 2) hemos determinado el rol de las AP en la preservación de los SE y la biodiversidad en Cataluña; 3) hemos desarrollado un marco conceptual para evaluar la vulnerabilidad de los bosques y su riesgo de pérdida de SE; y 4) hemos evaluado los patrones espaciales y las causas de la vulnerabilidad de los bosques a incendios y el riesgo asociado de pérdida de SE en Cataluña. La relación entre los stocks de carbono y la biodiversidad es en general positiva, con valores más elevados en el norte de España y en el sur del Québec. Valores de densidad y diversidad estructural elevados han favorecido los stocks de carbono, la biodiversidad de árboles y la biodiversidad global. Respecto a las AP, hemos encontrado más stocks de carbono, cobertura de hábitats de interés comunitario, hábitats prioritarios y lugares de interés geológico dentro de las AP que en sus áreas de influencia (o buffer zones), pero ninguno de los indicadores de biodiversidad ha mostrado diferencias entre las AP y sus áreas de influencia. Las AP con niveles de protección más elevados no han proveído de más SE y biodiversidad, o viceversa. Además, hemos propuesto un marco conceptual para evaluar la vulnerabilidad de los bosques y el riesgo de pérdida de SE, basado en los componentes de exposición, magnitud de la perturbación, susceptibilidad y ausencia de capacidad adaptativa. Finalmente, hemos aplicado este marco general a los incendios forestales en Cataluña. Los resultados muestran que la magnitud de la perturbación es el componente más importante que define el riesgo de pérdida de SE debido a incendios. El tipo funcional de bosque - especialmente las coníferas no Mediterráneas que tienen una menor capacidad adaptativa - es el factor más importante bajo condiciones extremas. El aumento de riesgo más grande está en bosques relativamente húmedos, situación que según las tendencias climáticas actuales pasará a ser más común en un futuro. En general, esta tesis ha contribuido a aumentar la evidencia científica de la relación positiva entre los stocks de carbono y la biodiversidad. También ha mostrado que la conservación en Cataluña solo es efectiva para mantener algunos SE y variables de conservación. También ha contribuido con un marco conceptual innovador sobre la vulnerabilidad de los bosques y el riesgo de pérdida de SE debido a perturbaciones del cambio climático. La aplicación de este marco conceptual a los incendios forestales ha demostrado implicaciones en el riesgo de pérdida de SE, que podrían servir para el desarrollo de políticas futuras de anticipación del riesgo, pudiendo servir de guía para la gestión forestal eficiente.<br>Forest ecosystems provide a wide variety ecosystem services (ES). Understanding how these ES are distributed across the landscape and identifying their main drivers is essential to inform policy to protect, enhance and restore these ecosystems. Besides, protected areas (PAs) are fundamental for biodiversity conservation and the provision of ES, yet their effectiveness in maintaining ES and biodiversity is still unclear. Currently, forests are increasingly under pressure from climate change, resulting in changes in disturbance regimes (e.g., wildfires, drought, insect-outbreaks and windstorms). Predicting where these natural hazards will occur in the future and to what extent forest ES will be affected are also fundamental research challenges. The general objective of this thesis is to analyze the spatial distribution of forest ES, their relevance in conservation and their vulnerability and risk to climate change hazards, especially wildfires. To do so, 1) we have analyzed the spatial distribution, relationship and drivers of forest carbon stocks and biodiversity in two regions and five subclimates; 2) we have determined the role of PAs in preserving ES and biodiversity in forests and shrublands of Catalonia; 3) we have developed a general framework of forest vulnerability and risk of losing ES due to different climate change hazards; and 4) we have assessed the spatial patterns and drivers of forest vulnerability to wildfires and the corresponding risk of losing ES in Catalonia. We have found a general positive relationship between carbon stocks and biodiversity, with the highest values in northern Spain (humid Mediterranean subclimate) and southern Quebec (temperate subclimate). High density and structural diversity have simultaneously favored carbon stocks, tree and overall biodiversity. The variables positively affecting carbon and biodiversity have been also driving their hotspots, emphasizing the viability of &#8216;win-win&#8217; solutions. Regarding PAs, we have found more carbon stocks, coverage of community-interest habitats, priority-habitats and geological-interest sites in PAs than in buffer zones, but none of the biodiversity variables considered have showed differences between PAs and buffer zones. PAs with higher degree of protection have not provided higher levels of ES and biodiversity, or vice versa. Furthermore, we have proposed a general framework to assess forest vulnerability and risk based on the components of exposure, hazard magnitude, susceptibility and lack of adaptive capacity. Finally, we have applied this general framework to the particular case of wildfires in Catalonia. The results have indicated that hazard magnitude is the most important factor defining ES at risk from wildfires. Climate is the main driving factor of ES at risk under average conditions, but forest functional type - in particular non-Mediterranean conifers that have low adaptive capacity - have gained importance under extreme conditions. The highest increases in risk have been found in relatively wet forests with currently low risk, which according to climate trends will become common in the future. Overall, this thesis has gained evidence on the positive relationship between carbon stocks and biodiversity and their main drivers in five subclimates, and has showed that the conservation strategy in Catalonia is only effective at maintaining some of the ES and conservation variables considered. It has also contributed with an innovative conceptual framework of forest vulnerability and risk of losing ES due to climate change hazards, constituting a basis for a systematic operationalization of forest risk and vulnerability. The application of this framework to the case of wildfires has showed relevant implications on the future risk of losing ES due to wildfires, which could contribute to future-oriented policies by anticipating conditions associated with particularly high risks and guiding efficient forest management.

Radionuclides are widely used in energy production and medical, military and industrial applications. Thus, understanding the behaviour of radionuclides which have been or may be released into ecosystems is important for human and environmental risk assessment. Modelling of radionuclides or their stable element analogues is the only tool that can predict the consequences of accidental release. In this thesis, two dynamic stochastic compartment models for radionuclide/element transfer in a marine coastal ecosystem and a freshwater lake were developed and implemented (Paper I and III), in order to model a hypothetical future release of multiple radionuclides from a nuclear waste disposal site. Element-specific mechanisms such as element uptake via diet and adsorption of elements to organic surfaces were connected to ecosystem carbon models. Element transport in two specific coastal and lake ecosystems were simulated for 26 and 13 elements, respectively (Papers I and III). Using the models, the concentration ratios (CR: the ratio of the element or radionuclide concentration in an organism to the concentration in water) were estimated for different groups of aquatic organisms. The coastal model was also compared with a 3D hydrodynamic spatial model (Paper II) for Cs, Ni and Th, and estimated confidence limits for their modelled CRs. In the absence of site-specific CR data, being able to estimate a range of CR values with such models is an alternative to relying on literature CR values that are not always relevant to the site of interest. Water chemistry was also found to influence uptake of contaminants by aquatic organisms. Empirical inverse relationships were derived between CRs of fish for stable Sr (CRSr) and Cs (CRCs) and water concentrations of their biochemical analogues Ca and K, respectively (Paper IV), illustrating how such relationships could be used in the prediction of more site-specific CRCs and CRSr in fish simply from water chemistry measurements.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>

Cette thèse a pour but d'étudier les méthodes d'évaluation des ressources environnementales : la méthode des Coûts de Transport (CT) à préférences révélées et la méthode d'évaluation contingente (EC) à préférences déclarées afin de proposer les contributions suivantes. Dans le chapitre 1, nous montrons qu'il est possible si les données sur les deux méthodes sont disponibles pour les mêmes observations, d'obtenir une meilleure mesure de la disposition à payer (DAP) par la combinaison des deux méthodes en utilisant la technique du maximum de vraisemblance simulé. Dans le chapitre 2, nous montrons qu'une nouvelle approche: le "special regressor" pourrait être une solution pour traiter les problèmes d'endogénéité en EC. En utilisant des données sur la DAP pour réduire les risques subjectifs de mortalité due à la présence d' Arsenic dans l'eau potable , nous montrons que le problème d'endogénéité du niveau subjectif de risque de mortalité peut être réglé efficacement. Enfin dans le chapitre 3, en utilisant une nouvelle enquête sur l'électrification rurale au Rwanda, nous proposons un nouveau design de la méthode d'EC en permettant aux personnes interrogées de choisir entre une contribution en temps ou en argent. Ainsi, en plus de mesurer une DAP classique, nous obtenons aussi une disposition à contribuer du temps mesurée en jours, qui est une mesure aussi voire même plus pertinente que la DAP dans le contexte d'un pays en développement<br>This dissertation aims at investigating the methods of the environmental resources valuation: revealed preferences Travel Cost (TC) method and stated preferences Contingent Valuation (CV) method in order to propose the following contributions. In chapter 1, we show that it is possible if both CV and TC data are available for the same observations, to obtain a better measure of willingness to pay (WTP) by combining the two methods using Simulated maximum Likelihood technique. In chapter 2, we show that the new special regressor approach could be a solution to treat endogeneity issues in CV. Using data on WTP for reducing subjective mortality risks due to arsenic in drinking water, we show that the endogeneity of the subjective mortality risk level can be treated effectively. Finally in chapter 3, using a new survey about rural electrification in Rwanda, we propose a new design for the CV method by allowing people to choose between a contribution in time or in money. Thus, in addition to measure a conventional WTP, we also obtain a willingness to contribute time measure which is as or even more relevant than WTP in the context of a developing country

As climate change continues, climactic extremes are predicted to become more frequent and intense, in some cases resulting in dramatic changes to ecosystems. The effects of climate change on ecosystems will be mediated, in part, by biotic interactions in those ecosystems. However, there is still considerable uncertainty about where and how such biotic interactions will be important in the context of ecosystem disturbance and climactic extremes. Here, I review the role of consumers in seagrass ecosystems and investigate the ecological impacts of an extreme climactic event (marine heat wave) and subsequent widespread seagrass die-off in Shark Bay, Western Australia. Specifically, I compare seagrass cover, shark catch rates, and encounter rates of air breathing fauna in multiple habitat types before and after the seagrass die-off to describe post-disturbance dynamics of the seagrass community, shifts in consumer abundances, and changes in risk-sensitive habitat use patterns by a variety of mesoconsumers at risk of predation from tiger sharks (Galeocerdo cuvier). Finally, I conducted a 16 month field experiment to assess whether xi loss of top predators, and predicted shifts in dugong foraging, could destabilize remaining seagrass. I found that the previously dominant temperate seagrass Amphibolis antarctica is stable, but not increasing. Conversely, an early-successional tropical seagrass, Halodule uninervis, is expanding. Following the die-off, the densities of several consumer species (cormorants, green turtles, sea snakes, and dugongs) declined, while others (Indo-Pacific bottlenose dolphins, loggerhead sea turtles, tiger sharks) remained stable. Stable tiger shark abundances following the seagrass die-off suggest that the seascape of fear remains intact in this system. However, several consumers (dolphins, cormorants) began to use dangerous but profitable seagrass banks more often following seagrass decline, suggesting a relaxation of anti-predator behavior. Experimental results suggest that a loss of tiger sharks would result in a behaviorally mediated trophic cascade (BMTC) in degraded seagrass beds, further destabilizing them and potentially resulting in a phase shift. My work shows that climactic extremes can have strong but variable impacts on ecosystems mediated in part by species identity, and that maintenance of top predator populations may by important to ecological resilience in the face of climate change.

226 pp.<br>UACE Firewise publications (8 total)<br>The Living with Wildfire in Arizona educational materials synthesize the most recent scientific and technically known information available on fire ecology for the ecosystems of Arizona, including mixed conifer forests, ponderosa pine forests, pinyon-juniper and oak woodlands, chaparral, grasslands and desert scrub, and riparian areas. The materials are meant to educate homeowners living in the wildland urban interface areas as to the natural function of fire in each ecosystem and what significant changes have impacted fire behavior over time. Information includes the natural role of fire, how and why fire behavior has changed over time, and the role that humans play in affecting that change in protecting themselves and their property.

Contagious bovine pleuropneumonia (CBPP) is a bovine bacterial disease of major economic importance in sub-Saharan Africa. Vaccination has been recommended to control the disease in endemic areas such as the Maasai ecosystems of Kenya and Tanzania; however, the currently used live attenuated vaccine has been reported to have poor vaccine safety and efficacy. To compare standard (current) and an improved (buffered) version of the live CBPP-vaccine, several epidemiological studies were carried out in Maasai cattle in Kenya between 2006 and 2008. Specifically, the aims were to estimate CBPP seroprevalence at herd and animal level; to identify risk factors for seroprevalence at both levels; to investigate the spatial distribution of seroprevalence; to compare post vaccination adverse events in cattle vaccinated with a standard and a buffered vaccine, and finally to compare efficacy of the two vaccines to induce seroconversion and to prevent development of clinical signs suggestive of CBPP. A cross-sectional study was carried out in 6872 cattle in 175 randomly selected herds from Loita and Mara divisions. A competitive ELISA revealed that 85% of the herds in the area had at least one seropositive animal and that seropositive herds were harbouring 11% seropositive cattle. A complement fixation test revealed that 46% of the herds had at least one seropositive animal and that seropositive herds were harbouring 4% seropositive cattle. A multivariable logistic regression analysis of the seroprevalence indicated that previous vaccination against CBPP, a history of CBPP outbreaks in the herd, animal age and the location of the herd in the division of Mara were positively correlated to seroprevalence. To investigate the observed difference in herd seroprevalence between the two divisions further, a spatial analysis was conducted. A SatScan test revealed clusters in Mara in areas identified by veterinary personnel as CBPP ‘hot spots’. A logistic regression using spatial information identified that location in the midland agro-ecological zone or close to a river and vaccination were positively associated with seroprevalence. To compare safety and efficacy of a standard and a buffered vaccine, two cohorts of approximately 40,000 cattle were used. The study showed that within 100 days post vaccination, 6.2 cattle per 1000 vaccinates developed adverse events, 4.1 of which were specifically attributable to vaccination and ranging from swelling of the tail to the tail sloughing off. This study revealed a slightly higher incidence of adverse events in cattle vaccinated with the buffered vaccine compared to the standard vaccine. A comparison of the efficacy of the two vaccines revealed that cattle vaccinated with the buffered vaccine had higher odds of seroconversion and lower odds of developing symptoms of CBPP, three and twelve months post vaccination respectively. The epidemiological studies conducted clearly show wide spread seroprevalence in the Maasai cattle. Given the (spatial) heterogeneity observed, control measures should probably be targeted in areas of increased risk (clusters). However, positive association of vaccination and seropositivity call for better diagnostics tests that can differentiate vaccinated from infected animals. Vaccination with buffered vaccine resulted in increased seroconversion, decreased clinical signs indicative of CBPP post vaccination and low seroprevalence post ‘outbreak’. Nevertheless, the increase in adverse events related to the buffered vaccine calls for further research into safer CBPP vaccines.