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Dissolved oxygen concentrations in the coastal ocean are controlled by a combination of physical and biogeochemical processes. Physical processes include turbulence, advection, and diffusion, biogeochemical processes include respiration, and photosynthesis. However, the influence of these processes on oxygen dynamics within coastal shelf sea environments are not fully understood. The main objective of this research was to develop new methodologies to enable measurements of in situ oxygen dynamics using the Eddy Correlation (EC) method in a dynamic shelf sea environment. EC data were collected to determine oxygen flux within two study sites L4 and Cawsands within the Western Channel Observatory (WCO). The first study provided further validation of the EC technique within a challenging environment by comparing EC measurements with the well-established microprofiler technique measurements. This study also provided an initial assessment of flux drivers within a seagrass habitat. The second study deployed the EC over a five-month field campaign. During this campaign other parameters were also collected such as: acoustic velocity data to estimate the contribution of the tide, conductivity, temperature and depth sensors, sediment composition and nutrient analysis. These complementary parameters aided assessment and understanding of drivers in relation to oxygen flux within the L4 study findings. A comparison of the relatively unstudied EC technique was made against a microprofiler, which measures diffusive point flux. Oxygen flux data between microprofiler and EC correlated during dark periods however did not during light periods. The EC captured photosynthetic drivers of oxygen flux during light periods. This validated the EC in a seagrass environment and demonstrated the microprofiler did not measure some key processes as it cannot capture all fluxes during photosynthetic periods. Previous studies have improved EC processing techniques and have reported the magnitudes of the fluxes at varying sites. However, little is known about benthic oxygen flux drivers, especially within coastal shelf sea environments, yet they have substantial ecological and economic importance. This study (Chapter 4) demonstrated that it is possible to gain insight into the controlling oxygen dynamics at the seabed by analysing the various tidal influences. Contribution of surface versus internal tides was assessed in relation to fluxes. While surface tides were shown to be the primary driver, there was a significant contribution driven by internal tides. During the weak stratification period there was a contribution from internal tides and it is suspected that as the summer progresses the internal tidal contribution would increase, becoming a stronger driver of flux. Building on this preliminary study, oxygen fluxes over five months were assessed by evaluating all major drivers of benthic oxygen flux at the L4 study site. The EC technique, which measures total turbulent oxygen flux, along with accompanying instruments was used to document and assess drivers of benthic oxygen uptake over the five-month field campaign at L4. Drivers such as nutrients, temperature, the dumping of dredged spoils and chlorophyll concentration were assessed. Flux correlated weakly with flow velocity over the five-month sampling campaign. Furthermore, without sediment analysis and settling chambers at the specific location of where the EC fluxes were measured, the contribution of dredge material, plankton bloom and nutrients have on benthic oxygen flux cannot be conclusively quantified. A lack of data capturing nutrients within the sediment and ADCP data throughout the five-month sampling campaign at L4 meant that a complete quantification of the drivers of oxygen flux at this site was not achievable. A more complete picture could be obtained if a microprofiler (measuring diffusive flux) and benthic chambers (measuring sediment oxygen uptake) were deployed alongside the EC as well as settling chambers and sediment nutrient analysis. Nonetheless, this study has made advances in EC processing and has provided a first insight into tidal and oxygen dynamics at a historical research station. The work presented has provided further validation of the EC technique and processing methods within a challenging environment by comparing EC and microprofiler measurements. Furthermore, this study has provided the first insight into water column oxygen budgets, with a particular focus on the influence of benthic oxygen flux drivers, in this shelf sea environment.

This thesis explores Tsimane understandings and creations of varying forms of sociality. Each chapter addresses different but related issues concerning sociality. Fieldwork was carried out in three riverine settlements over the period from December 1991 to August 1994. The thesis shows that sociality is created and perpetuated by individuals as a processual endeavour, and does not amount to a tangible structure predicated upon fixed social relationships. Community in a physically bound sense is not found amongst the Tsimanes. Given forms of sociality are shown to rest more upon an appropriateness or inappropriateness of mood or affectivity. These are created and effected by subtle details of each individual’s presence amongst others. Social presence is understood by the Tsimanes as both potentially nurturant and predatory. Tsimanes are explicit about their ideas of preferred and abhorred social presence and behaviour of human and non-human others. This thesis explores ways in which such ideas are articulated to create a discourse on social ethics. A Tsimane aesthetics of social living carries with it practical implications for creating and perpetuating forms of sociality. An underlying theme of the thesis is one of mobility and the oscillating nature of Tsimane movements between different groups of kin and affines, and between moods and forms of sociality. I demonstrate that the high value placed by the Tsimanes upon movement, and the enjoyment they experience from it, most efficiently enable the achievement of correct social existence. A lack of knowledge and intention, ultimately resulting in illness and death, are principally deemed to occur as a result of immobility.

Increasing attention in the conservation sciences is being paid to the existence of a ‘gap’ between research and action. Although much research has implications for management, rarely does it have real impact on the problems it seeks to address. As a result researchers are increasingly concerned with demonstrating that the impacts of their research go beyond academia. Recent scholarship has proposed various solutions for ‘bridging the gap’. However, missing from the debate is a closer analysis of who lies within the gap and what happens in that place: What kinds of encounters and misencounters occur between scientists and non-scientists during the practice of doing scientific research, especially in situations that include ‘everyday’ activities and communication (i.e. fieldwork)? This thesis approaches the issue by enacting a Participatory Action Research methodology in the Amazonian region of Madidi National Park in Bolivia, that includes a quantitative analysis of past research, semi-structured and unstructured interviews (n = 137), and workshops and focus groups (n = 12) with local inhabitants, scientists and park guards. The study demonstrates the significance of currently unacknowledged or undervalued components of the research-action gap, such as power, respect and recognition. It explains how and why within spaces of encounter and misencounter between scientists and local people, knowledge can be exchanged or hidden away, worldviews can be expanded or further entrenched, and scientific research can be welcomed or rejected. It reconceptualises the gap as a crucial, productive space within which asymmetrical relations of power between scientists and local people have the potential to be transformed. In additional, the thesis discusses the implications of these spaces for the future of conservation science and practice in postcolonial contexts, with an explicit call to action for researchers to reprioritize the who at the gap between research and action.