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Understanding social-ecological system (SES) feedbacks and interactions is crucial to improving societal resilience to growing environmental challenges. Social-ecological systems are usually researched at one of two spatial scales: local placed-based empirical studies or system-scale modelling, with limited efforts to date exploring the merits of combining these two analytical approaches and scales. Here, we take a multiscale interdisciplinary approach to elucidate the social dynamics underpinning cross-sectoral feedbacks and unintended consequences of decision-making that can affect social-ecological system vulnerability unexpectedly. We combined empirical place-based research with the Robustness Framework, a dynamic system level analysis platform, to analyse the characteristics and robustness of a coastal SES in Cornwall, UK. Embedding place-based empirical analysis into a broader institutional framework revealed SES feedbacks and "maladaptations". We find that decentralisation efforts coupled with government austerity measures amplify second-order (reputational) risks. This prompted temporal policy trade-offs, which increased individual and community vulnerability and reduced social-ecological system robustness, impeding local adaptation to climate change. We identify opportunities to ameliorate these maladaptations by (1) implementing coordination rules that can guide policymakers in instances of conflicting coastal management pressures, and (2) recognising how second-order risks influence decision-making. This work demonstrates the strengths of combining local and regional analyses to assess the robustness of social-ecological systems exposed to environmental changes, such as climate change and sea level rise. Our results show how analysis of the multiscale effects of climate policies, decision-making processes and second-order risks can usefully support local climate change adaptation planning.

Estuaries are crucial areas from a socio-environmental point of view, being the ecosystem for a wide range of life forms, the economic foundation of many coastal nations, and the connection between land and open sea. Communities inhabiting these areas need to transport people and commodities by water, thus entailing the dredging of waterways to inland ports. Deepening of navigation channels in estuaries usually results in the alteration of tidal behavior and related morphodynamic processes. The knowledge of the spatio-temporal response of estuaries to dredging activities is still limited; therefore there is a real need to use and combine different methods and tools when exploring the effects of such interventions. It is the aim of this Thesis to enhance the understanding of the main morphodynamic processes involved in the dredging activities, and the implementation of multiple tools when assessing these projects in estuaries. This Thesis achieved the objective using data and field measurements in two Andalusian estuaries, where both the role of the forcings and the dredging strategies differ: the Guadalquivir estuary and the Punta Umbría inlet. In the case of the Guadalquivir estuary, whose inland port belongs to the Spanish Port System, the presence of numerous stakeholders pose a challenge when managing dredging projects. The recent proposal to deepen the navigation channel confront the interests of different parties due to the possible environmental impacts in the system. This concern attains the effects of tides and freshwater discharge into the turbidity, saline intrusion and, generally, the ecological and chemical state of water masses. In the case of Punta Umbría inlet, the Regional Government of Andalusia manages the inland port. A database specifically designed to assess the dredging projects in these regional ports was used. The evaluation of all these dredging activities executed in the past twenty years pointed Punta Umbría as a particularly problematic port. Indeed, it has one of the highest average prices per intervention, where the volume of mobilized sediment in the navigation channels is the second highest. ; Tesis Univ. Granada. Programa Oficial de Doctorado en: Dinámica de Flujos Biogeoquímicos y sus aplicaciones

Abstract. Surface roughness influences the release of avalanches and the
dynamics of rockfall, avalanches and debris flow, but it is often not
objectively implemented in natural hazard modelling. For two study areas, a
treeline ecotone and a windthrow-disturbed forest landscape of the European
Alps, we tested seven roughness algorithms using a photogrammetric digital
surface model (DSM) with different resolutions (0.1, 0.5 and 1 m) and
different moving-window areas (9, 25 and 49 m2). The
vector ruggedness measure roughness algorithm performed best overall in distinguishing between
roughness categories relevant for natural hazard modelling (including shrub
forest, high forest, windthrow, snow and rocky land cover). The results with
1 m resolution were found to be suitable to distinguish between the
roughness categories of interest, and the performance did not increase with
higher resolution. In order to improve the roughness calculation along the
hazard flow direction, we tested a directional roughness approach that
improved the reliability of the surface roughness computation in channelised
paths. We simulated avalanches on different elevation models (lidar-based)
to observe a potential influence of a DSM and a digital terrain model (DTM)
using the simulation tool Rapid Mass Movement Simulation (RAMMS). In this way,
we accounted for the surface roughness based on a DSM instead of a DTM,
which resulted in shorter simulated avalanche runouts by 16 %–27 % in the
two study areas. Surface roughness above a treeline, which in comparison to
the forest is not represented within the RAMMS, is therefore underestimated.
We conclude that using DSM-based surface roughness in combination with DTM-based surface roughness
and considering the directional roughness is promising for achieving better
assessment of terrain in an alpine landscape, which might improve the natural
hazard modelling.