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This thesis examines the cultural and material transformation of West Berlin by concentrating on its unique history as island city from 1961 to 1989. The construction of the Berlin Wall in 1961 radically transformed the urban fabric for a second time after wartime destruction and consolidated West Berlin as an urban enclave. Land banking, protracted geopolitical negotiations, slow economic recovery, and zoning plans that kept the possibility of reconnecting the city open, held up post-war reconstruction. With the need to heavily subsidize the city’s economic sectors, and other aspects of urban life, the enclave was kept on geopolitical life-support for three decades, allowing a diverse range of alternative spaces and intellectual ideas to evolve. This thesis investigates West Berlin’s role as an experimental city by extending previous geographical work on the intersections of the human body, nature, and urban space. A series of four empirically centred case studies illuminates distinctive aspects of the cultural and material particularities of the enclave. We explore the continuities and discontinuities of Weimar Berlin’s legacy through attempts to build a modernist nature-culture synthesis in the early postwar years, and discuss sonic experimentation in the moulding of urban space into a state-of-the-art concert hall. Anomalous spaces or terrains vagues emerged as accidental by-products of the city’s geopolitical division, and were appropriated as ecological refugia and islands of autonomous social and cultural life. Scientific and cultural experiments enchanted these indeterminate spaces, and culminated in a progressive planning proposal envisioning an alternative city. In the 1970s, the experimental enclave partly echoed the cultural ebullience of the Weimar years, and served as the pivotal terrain for a vibrant cultural life to emerge. Shortly before the fall of the Berlin Wall, West Berlin emerged as a “radical intellectual island” through the strong presence of feminist theory, and a multifaceted progressive local politics. This thesis draws on oral history, archives, and ethnographic observations to revisit the forgotten history of West Berlin as an alternative space.

The research presented in this thesis integrates field observations and sampling, data from controlled laboratory experiments with a radially-symmetric fluid flux model to investigate permeability controls on degassing processes operating during lava dome eruptions at silicic volcanoes. Laboratory permeability measurements were made on samples collected systematically across the marginal shear zone of a lava spine at Mount Saint Helens (MSH), Washington, USA, from the 2004-08 eruption, at room temperature and confining pressures up to 85 MPa. Permeability experiments were also performed on samples of massive dacite from the spine core at a range of temperatures up to 900°C and a confining pressure of 10 MPa. A simplified radially-symmetric fluid flux model was developed which incorporated the observed structure of the conduit at Mount Saint Helens and the measured permeability profile to show the effects of the permeability on the magnitude and direction of fluid flow. Permeability was found to be essentially isotropic in the conduit interior but highly anisotropic in the marginal shear zone rocks. Vertical permeability in the marginal rocks is increased by two orders of magnitude, through the formation of an aligned shear fracture network. Ultracataclasite shear bands in the fault core also decreased the horizontal permeability by two orders of magnitude. Permeability was also seen to decrease by around four orders of magnitude as temperature was increased to 900°C. In contrast to previous work that assumed significant lateral transport of gases, modeled fluid flow using the experimentally determined permeability data shows that the vertical volatile volumetric flow rate will be orders of magnitude greater than the horizontal rate into the wall rock; more than 90% of volatile flow would have been partitioned vertically within the conduit-margin fault zone, consistent with the location of gas and ash venting during the eruption. Changes in permeability with temperature indicate that magma rising in the conduit becomes progressively more permeable to gas escape during ascent and crystallisation. When applied to gas sealing processes, the intrusion of molten lava under a solidified plug and the associated heating may cause the permeability of the overlying rock to decrease sufficiently that gas escape is inhibited, allowing for the build up of pressure and potentially an explosive eruption.

This thesis investigates the processes of identity formation that young Mexican women living in the United States-Mexico borderlands engage in today. It examines how they perform multiple and transnational identities to negotiate discourses of gender, race and class across the everyday spaces they inhabit. It shows that young women leverage their parents’ Mexican heritage and migration narratives as proxies for their own Mexican identity ascription, and it grants salience to parental strategies to instil within their daughters valuable cultural and social capital via la familia. It simultaneously contends that young women develop themselves as partially ‘-American’, a process which can function to also engender new interpretations of their Mexicanness as it is informed by their friends and peers. These performances are strongly rooted in the spatial worlds young women inhabit, most especially, the home and school spaces. Young women both conform to and contest normative expectations of them that centre on the gendered division of labour within the home, their degrees of freedom, and their educational trajectories. The thesis demonstrates that young women engage in transnational practices as a conscious strategy to make sense of the multiply conflicting identity discourses that are present in their lives. By ascribing to and performing strategically what they perceive to be Mexican and/or more American identities, and by utilising carefully the funds of social and cultural capital available to them, young women manage to create valuable and positive lives for themselves in a socio-cultural and economic landscape that can tend otherwise to devalue and exclude them. Rooted in, and contributing to, critical feminist and race theories, this thesis draws upon fifty-five in-depth qualitative interviews conducted with young Mexican women aged 14-24 during eleven months of ethnographic research in Encinitas, North County San Diego, California in 2009-10.

This thesis focuses on the ecology and palaeoecology of diatom-duckweed relationships and utilises a combined experimental, ecological and palaeoecological approach. In particular, the study sought to determine the potential of the epiphytic diatom Lemnicola hungarica to be utilised as a proxy indicator of past dominance of duckweed (Lemna) in small ponds. To this end, contemporary sampling of epiphytic diatom assemblages from a variety of macrophytes (including multiple samples of free-floating plants) were collected from around the world and analysed for diatom epiphytes. In this study, even despite significant environmental gradients, L. hungarica showed a significant association with free-floating plants (including Lemna spp.) as did Sellaphora seminulum. To determine whether this relationship might be used to infer Lemna-dominance in sediment cores, diatom assemblages were analysed in surface sediments from English Lemna and non-Lemna covered ponds and in a core from a pond (Bodham Rail Pit, eastern England) known to have exhibited periods of Lemna-dominance in the past. In both cases, the data suggested that both L. hungarica and S. seminulum were excellent predictors of past Lemna-dominance. Finally, to infer the consequences of Lemna-dominance for the long-term biological structure and ecosystem function of the Bodham Rail Pit, the sedimentary remains of diatoms, plant pigments, and plant and animal macrofossils were enumerated from two sediment cores. These stratigraphic data were compared with the diatom Lemna-indicator metric which indicated three distinct Lemna cycles. Sediment core analyses suggested major compositional, structural and ecological changes brought about by the Lemna cycles, especially in the submerged macrophyte community and in fish-invertebrate relationships. These data reveal that duckweed proliferation, often brought about by eutrophication and terrestrialisation in ponds, can result in dramatic ecological changes due to a strong physical ecosystem engineering effect.

Recent decades have been marked by growing awareness of the need for more sustainable consumption across society. Young people have been identified as well-placed to drive new (sustainable) modes of consumption through their participation in trend-setting youth cultures, as well as their roles as influential members of households. Yet, whilst the socio-cultural situation of young people makes them an appealing focus for sustainability promoters, the ways in which socio-cultural factors both enable and constrain their capacity to consume sustainably has been the subject of little investigation. The aim of this thesis has been to extend understanding of young people’s consumption in order to increase the efficacy of sustainability initiatives targeting youth. As a corrective to the preoccupation with acquisition that has dominated extant youth consumption studies, this project has taken divestment as its focus. Not only has this permitted a response to accusations of wastefulness amongst the young, it has focused much-needed attention on the socio-cultural forces underpinning young people’s relationships with their possessions. Based on qualitative research with young people in East Anglia, this thesis argues that the problem of waste (and thus unsustainability) in young people’s consumption does not (primarily) concern the flow of items into the waste stream. Rather, waste is produced when possessions fall out of use and remain unused over time, and this is driven by lack of agency in response to powerful socio-cultural forces. It is suggested that addressing this requires facilitating young people’s attempts to contest waste-making imperatives within extant cultural norms, and that sustainability promoters might attend to this through building young people’s competence, self-efficacy and desire to prolong the lives of their possessions. In sum, this thesis argues that young people can drive sustainable consumption if they are able to reclaim power over their consumption from the market and consumer culture.

Neoliberal governance strategies have been hegemonic in shaping global policy toward Marine Protected Areas (MPAs) over the past two decades. This impact has manifested itself in two key dimensions: the prominence given to public-private partnerships (PPPs) and the dependency upon civil society, particularly in the form of non-governmental organisations (NGOs). As a result, it is necessary to give primacy to the implication of PPPs and the role of NGOs in considering how best to govern MPAs. This is particularly the case in relation to efforts which seek the ‘right’ combination of ‘the market’, ‘the people’ and ‘the state’. This thesis investigates the California Marine Life Protection Act (MLPA) implementation process, and particularly the MLPA Initiative, which is widely publicised as a successful case of a science-based stakeholder-driven process through PPP. The thesis involves a thorough exploration of how an ideal combination could be achieved based on the Central Coast Study Region (CCSR) MLPA implementation process. Number of literary sources identified four key factors which have significantly contributed to the implementation of MLPA: 1) A strong legal mandate 2) Strong political will 3) A substantial level of stakeholder participation 4) Effective PPPs However, despite the widely publicised claims, research findings suggest that finding the ‘right’ combination for the MLPA implementation process remains a difficult task. The strong legal mandate, which has provided the foundation for the science used, constrained the stakeholder participation process. Indeed, it suggests that the terms ‘science-based’ and ‘stakeholder-driven’ could be to some extent, oxymorons, whilst strong political will could potentially compromise stakeholder participation. Effective PPPs for the MLPA Initiative represent a conundrum for PPP, since NGOs, including philanthropic foundations, increasingly exercise their influence on public policy to push through their agendas. Subsequently, PPP could potentially compromise the legitimacy of the process. Finally, the research findings suggest that the substantial level of stakeholder participation may not be a panacea for designating MPAs.

In this thesis, a modelling approach is taken to investigate the sea ice and ocean mixed layer over the Antarctic continental shelf. A primary motivation is to understand why the Amundsen and Bellingshausen (AB) shelf seas are flooded by Circumpolar Deep Water that is several degrees Celsius warmer than the cold shelf waters prevalent in the Weddell and Ross (WR) seas. An idealised sea ice-mixed layer model is used to investigate this apparent bimodal distribution. The formation of shelf waters (fully mixed water column) is shown to be driven primarily by the ‘cold’ WR atmospheric forcing, independent of the ocean profile, suggesting that the regional difference in atmospheric forcing alone is sufficient and perhaps necessary to account for the bimodal distribution in shelf sea temperature. Coupling the mixed layer model to the sea ice model CICE extends the study to the entire Southern Ocean, and provides a more accurate representation of the sea ice and the processes controlling mixed layer deepening within the shelf seas. The model captures well the expected sea ice thickness distribution, and produces deep (>500 m) mixed layers in the WR shelf seas each winter. Shallower wintertime mixed layers are produced in the AB seas. Deconstructing the surface mechanical power input to the mixed layer, shows that the salt flux from sea ice growth/melt dominates the evolution of the mixed layer in all four shelf seas. An analysis of the sea ice mass balance demonstrates the contrasting mean annual ice growth, melt and export within each of the four shelf seas. The CICE-mixed layer model is also used to investigate recent and future trends in the sea ice and mixed layer. The recent ERA-Interim forced simulation compares well with the observed regional trends in ice concentration, but shows mainly insignificant trends in the sea ice, the surface inputs of salt and heat, and the mixed layer depth over the shelf seas. The future HadGEM2-ES forced simulation shows, in-contrast, significant declines in the sea ice, the surface inputs of salt and heat and the mixed layer depth over the shelf seas. This simulation, however, shows poor agreement with recently observed sea ice trends; highlighting the on-going inability of climate models to accurately simulate Antarctic climate trends.

Anthropogenic land use changes have increasingly altered and fragmented floodplain landscapes. While the impacts of these alterations are being recognised for many plant and vertebrate taxa, limited information is available for highly diverse invertebrate families. Using a variety of approaches to diversity measurement, this thesis investigates carabid and staphylinid beetle assemblages across a range of chalk floodplain habitats in Norfolk, England. It aims to establish the roles anthropogenic and environmental factors play in shaping their communities in order to inform tailored conservation practices. Site management was identified as the dominant influence on beetle assemblages, underpinning the development of distinct communities amongst floodplain meadow, fen and woodland habitats. Surrounding landscape configuration also influenced beetle assemblages, confirming the wide-ranging, multi-faceted impacts of anthropogenic land use changes. Beetle communities in floodplain woodlands were both specimen- and species-rich across the highly heterogeneous forest microhabitats hosted within. Functional diversity analysis highlighted the vulnerability of certain functional groups to management and fragmentation. It confirmed the importance of conserving remaining remnants of natural floodplain woodlands to support vulnerable beetle communities. Floodplain fens harboured rare species, while their overall beetle diversity was surprisingly low. This was attributed to their limited habitat extent, fragmented distribution, and potentially legacies of past land use. This thesis suggests that traditional management regimes must be maintained in fen habitats, and their connectivity promoted, to safeguard and restore the unique biological communities supported within. Anthropogenic land use changes have increasingly altered and fragmented floodplain landscapes. While the impacts of these alterations are being recognised for many plant and vertebrate taxa, limited information is available for highly diverse invertebrate families. Using a variety of approaches to diversity measurement, this thesis investigates carabid and staphylinid beetle assemblages across a range of chalk floodplain habitats in Norfolk, England. It aims to establish the roles anthropogenic and environmental factors play in shaping their communities in order to inform tailored conservation practices. Site management was identified as the dominant influence on beetle assemblages, underpinning the development of distinct communities amongst floodplain meadow, fen and woodland habitats. Surrounding landscape configuration also influenced beetle assemblages, confirming the wide-ranging, multi-faceted impacts of anthropogenic land use changes. Beetle communities in floodplain woodlands were both specimen- and species-rich across the highly heterogeneous forest microhabitats hosted within. Functional diversity analysis highlighted the vulnerability of certain functional groups to management and fragmentation. It confirmed the importance of conserving remaining remnants of natural floodplain woodlands to support vulnerable beetle communities. Floodplain fens harboured rare species, while their overall beetle diversity was surprisingly low. This was attributed to their limited habitat extent, fragmented distribution, and potentially legacies of past land use. This thesis suggests that traditional management regimes must be maintained in fen habitats, and their connectivity promoted, to safeguard and restore the unique biological communities supported within. This study highlights the importance of adopting habitat-specific conservation objectives to ensure the persistence of specialist species, whilst maintaining a matrix of different floodplain habitats to preserve wider catchment diversity. As anthropogenic impacts on floodplain environments will continue, the potential role of beetles in biodiversity research and conservation, and in particular of staphylinid beetles that dominate the floodplain ground fauna, warrants increasing interest and recognition.

In freshwater bodies algae provide key ecosystem services such as food and water purification. This is the first systematic assessment of biodiversity, biomass and distribution patterns of these aquatic primary producers in the Okavango Delta (Botswana), a subtropical flood-pulsed wetland in semiarid Southern Africa. This study delivers the first estimate of algal species and genera richness at the Delta scale; 496 species and 173 genera were observed in 132 samples. A new variety of desmid (Chlorophyta) was discovered, Cosmarium pseudosulcatum var. okavangicum, and species richness estimators suggest that a further few hundred unidentified species likely live in this wetland. Rare species represent 81% of species richness and 30% of total algal biovolume. Species composition is most similar within habitat types, thus varying more significantly at the Delta scale. In seasonally inundated floodplains, algal species / genera richness and diversity are significantly higher than in permanently flooded open water habitats. The annual flood pulse has historically allowed more diverse algal communities to develop and persist in these shallower and warmer environments with higher mean nutrient levels and more substrata and more heterogenous habitats for benthic taxa. These results support the Intermediate Disturbance Hypothesis, Species-Energy Theory and Habitat Heterogeneity Diversity hypotheses. Higher algal biodiversity supports higher algal biomass in the floodplains, where species form three-dimensional communities of attached and periphytic algae requiring more nutrients than phytoplankton assemblages. Multivariate analyses demonstrate that habitat type, flooding frequency and conductivity most importantly influence the relative abundance of algal species, genera and phyla in the Okavango Delta. This study’s findings highlight how the preservation of water level fluctuations and habitat heterogeneity is crucial to maintaining biodiverse and thus resilient food webs in this unique ecosystem which faces increasing anthropogenic threats, such as global warming and upstream water abstraction plans.