Thesis (M.S.)--University of California, Santa Cruz. / Typescript. Bibliography: leaves 75-78.

Thesis (M.F.A.)--Ohio State University, 2006. / Includes bibliographical references (leaves 122-128). Available online via OhioLINK's ETD Center

Thesis (Ph. D.)--University of Florida, 1982. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 249-265).

Nitrate determination and ion-selective electrodes, with particular emphasis on the nitrate selective electrode, are reviewed. A new electrode for nitrate has been developed, by covalent attachment of appropriate sensor groups to a robust polymer matrix, with a view to improving the lifetime and the applications of the electrode to include hostile environments. The QAS (I) were prepared as sensor materials.(1) R' = R" = R''' = ethyl(2) R' = allylR" = R''' = methyl, ethyl, propyl(3) R' = R" = allylR''' = methyl, ethyl, propyl, butyl(4) R' = R" = R''' = allylX- = Cl, Br. (I) [diagram]. The production of membranes by cross-linking the sensors (I) with styrene-b-butadiene-b-styrene triblock elastomer (SBS) using a free radical initiated cyclopolymerisation is described. Various methods of membrane preparation have been investigated, and a convenient one-step solvent casting procedure identified and optimised. A range of membranes has been prepared and their physical and electroanalytical properties evaluated. The cross-linked density of the polymers was calculated from swelling measurements and the Flory-Rehner equation, the extent of covalent attachment has been derived from Kjeldahl analyses. The performance of the membranes as ion-selective electrodes is presented and discussed. Several electrodes showed fast response, long lifetime and Nernstian behaviour in the range 10-1 - 10-4 mol dm-3, but their selectivity was inferior to present commercial electrodes. A number of materials were introduced as mediators in order to improve the selectivity of the membranes. A possible mediator (O-nitrophenyloctyl ether) was identified and an analogue (O-nitrophenyl-w-undecylenyl ether) prepared which had suitable functionality for covalent attachment to the polymer. Unfortunately the inclusion of this material did not improvethe selectivity to chloride and the reasons for this are discussed.

The central question addressed in this thesis is whether descriptions of the dynamics of ecological systems at one scale may be effectively used as descriptions of the dynamics of ecological systems at larger scales. This question is addressed in the context of the dynamics of fungal communities. A simple experimental system and complementary theoretical approach, in the form of an individual-based (cellular automaton) model, is presented. Experimental results derived from small-scale systems are used to quantify parameters of the model; results from large-scale experimental systems serve to test the model. The theoretical analyses clearly demonstrate that the dynamics observed are a result of both local and non-local features of the experimental system. In cases such as this the immediate extrapolation of results derived from xperiments conducted out of the context of the community to represent system scale behaviour is not possible. In response to this observation a generic framework is developed to allow the consideration of effects at a range of scales through contextual parameterisation of localised dynamics. The framework is directed toward plant systems where a large body of experimental data exists, and may be parameterised by that experimental data. It represents the essential features of individual interactions in terms of competition for space and resource, and the behaviour of a given plant is described in terms of functional traits. Model runs demonstrate complex community patterns suggestive of a known biological phenomena, succession, that arises as a consequence of the coupling between the community and environment. This coupling may allow the long-term coexistence of species through some particular balance in individual function (traits) across the community. A search mechanism is determined to allow combinations of trait values at the scale of the individual to be assessed for a particular community-scale phenomenon. Initial results demonstrate that this mechanism may identify and converge on combinations of trait values that give rise to, in this case, a simple measure of diversity. The manner in which the generic framework developed may be applied to further the investigation into fungal community dynamics is addressed.

The morphological and ecologicalevolution of middle-upper Eocene planktonic foraminiferal family Hantkeninidae is investigated in the context of the dramatic palaeoceanographic and climatic changes that marked the transition from Paleogene "greenhouse" to Neogene "icehouse" climatic conditions. Morphometric analysis proves that evolution in family Hantkeninidae was gradual but complex in detail with periods of relative stasis. Multiple lines of evidence demonstrate that Hantkenina evolved from planispiral clavate genus Clavigerinella and not, as was previously believed, from Pseudohastigerina micra. The ancestor of Clavigerinella was probably a low trochospiral form Paragloborotalia sp., which has been recognized for the first time in this study at a number of sites. Trends in chamber inflation, tubulospine angle and the position of the tubulospine on each chamber show the most dramatic evolutionary changes, indicating that these are the most useful characters for taxonomy. These morphological changes correlate well with known palaeoceanographic changes as well as the shift in hantkeninid ecology from a deep to a surface water habitat. Hantkeninids underwent pronounced adaptive evolution in depth habitats during the initial phase of the climatic transition. Lower middle Eocene forms lived in a cool deep-water environment within or below the oceanic thermocline and shifted to warmer surface waters in the late middle Eocene. They evolved in the low latitudes and were primarily. a tropical-subtropical group. The occurrence of Hantkenma australis at relatively high northerly and southerly latitudes during the middle Eocene may record a temporary expansion of warmer water conditions into these regions, possibly representing a hitherto unknown "hyperthermal" event. Clavigerinella is rare in middle Eocene open-ocean sequences but occasionally occurs in relative abundance in other localities (such as on continental margins and oceanic seamounts), suggesting that it was specialized for living in upwelling regions. A revised taxonomy of family Hantkeninidae is presented that reflects new understanding ofhantkeninid evolution. The reconstructed phylogeny demonstrates that the tubulospine-bearing genera Hantkenina and Cribrohantkenina represent a monophyletic clade. Multivariate analysis suggests that more than one morphological population existed at several times and that these may represent biological species. The results demonstrate that the hantkeninids are not merely passive recorders of ocean conditions but have instead evolved morphology and changed habitat in response to climate change.

The landscape of the childhood victimization literature is shifting, with a growing number of researchers emphasizing the importance of designing studies that account for and aim to disentangle the interconnections among victimization experiences. This is a notable contrast to the bulk of the scientific inquiry to date, which has tended to examine victimization experiences in isolation from one another and has created victimization-specific models of risk. On the other hand, the multiple victimization field aims to better understand the overlap among risk factors and the co-occurrence across victimization experiences to create general or non-specific risk models for childhood victimization. From this field emerged the concept of multiple victimization (defined as exposure to more than one type of victimization within a specified time period), that has been established as the unfortunate norm among victimized children. The current dissertation was designed not only to help attain a better understanding of the phenomenon of childhood multiple victimization but also to contribute to our understanding of the frequency, co-occurrence, and risk (grounded in the ecological framework) of childhood multiple victimization. This dissertation addresses important shortcomings of the published literature, such as the scarcity of studies that account for the co-occurrence among victimization experiences, the limited victimization data on school-aged children and clinical samples, and the dearth of studies that test comprehensive risk models of multiple victimization. Caregivers of school-aged children (N = 213) in the Ottawa/Gatineau area participated in the online study, which involved the completion of a 30-minute questionnaire package that assessed their child’s victimization experiences as well as child (e.g., sex, age), family (e.g., caregiver psychosocial functioning, family functioning), and neighbourhood (e.g., safety) factors. Results provided support for the ubiquitous nature of childhood multiple victimization (in the past year and lifetime) as well as for the common co-occurrence of various victimization experiences. Specifically, while a certain overlap was found across all victimization forms, conventional crimes and peer and/or sibling victimization co-occurred most often in this school-aged sample. In addition, victimization forms that may be qualified as “severe” (sexual victimization, Internet victimization, maltreatment) tended to co-occur with many additional forms and were rarely reported on their own. Findings highlighted the important associations between victimization exposure and psychosocial difficulties (anxiety, depression, aggression, and posttraumatic stress), and weighting techniques (i.e., weighting severe victimization forms more heavily) were not found to significantly contribute to better predictability of psychosocial difficulties. Turning to the risk models, a number of correlates of childhood multiple victimization were identified, most notably family variables including family dysfunction, caregiver psychosocial functioning, and substance use problems. However, a number of correlates (particularly socio-demographic factors) were also found to vary according to the victimization experiences assessed, providing partial support for the specificity assumption whereby victimization risk models vary according to the victimization form assessed. The theoretical and applied implications of research findings for efforts aimed at addressing childhood multiple victimization were also discussed.

The problem: For protected areas to remain relevant, we need to understand their impact on a wide set of conservation objectives and environmental outcomes. We also need to evaluate how this influence relates to the socio-ecological environment within which they occur. This is a complex endeavour requiring a pluralistic approach, which draws on a wide range of interdisciplinary fields. Research question: This thesis addresses the following question: What effects do mountain protected areas have on ecosystem services over time and how does this influence relate to broader socio-economic and ecological drivers of landscape change? Aim and objectives: I use a pluralistic, socio-ecological framing to assess the impact of ~40 years of mountain protection, drawing on comparisons of ~30 and ~40 years before and after protection respectively, with an adjacent area of similar terrain informing scenarios of counterfactual conditions. I also investigate what types of values (economic and intrinsic) are important when determining the impact of mountain protected areas. Thesis approach and methods: I operationalise the concepts of socio-ecological systems, ecosystem services, land use transitions and counterfactuals to investigate socio-ecological change and how it relates to protected area impact in the Groot Winterhoek, a mountain catchment in the south-western Cape of South Africa. This mountain catchment is important for regional water supplies for agricultural and domestic uses and falls in the Cape Floristic Region, a global biodiversity hotspot. It is comprised of privately owned mountain wildlands and a wilderness-protected area, known as the Groot Winterhoek Wilderness Area, established in 1978 (gazetted in 1985) which forms part of the Cape Floristic Region World Heritage Site. I combine methods from social science, ecology, environmental geography, geomatics and hydrology to understand the history of land use and cover (land use/cover) and associated ecosystem service trade-offs, how they are perceived by landowners as well as their wider impact on the region. Specifically, I assess the impact of protection on land use/cover, vegetation, fire and water flows over the last ~50 years, by comparing and contextualising results of change within the protected area to alternative scenarios of “no protection” (the counterfactual conditions). Vegetation and land use/cover change inside the protected area were determined respectively using 72 repeat terrestrial photographs and vegetation surveys, and an analysis of orthorectified aerial imagery. Methods used to construct the counterfactual scenarios of mechanisms (e.g. changes in land use/cover) that would likely drive vegetation changes inside the protected area included: i) 60 repeat surveys and in-depth interviews with landowners adjacent or proximal to the protected area owning unprotected land of similar terrain to the protected area; and ii) land use/cover change analysis of orthorectified aerial imagery of adjacent unprotected land of similar terrain before and after protected area establishment. 4 This latter information was used to understand the role of the protected area in driving vegetation changes inside the protected area. Social, biophysical and remote sensing results were directly used to parameterise land use/cover components of a hydrological model to determine the influence of protection on water flows. Specifically, water flows were simulated for the current state of the environment inside the protected area as well as for several counterfactual scenarios i.e. the alternative land use/cover scenarios of “no protection”. These counterfactual scenarios included land use/cover at two-time steps of ~30 and ~8 years before protection and one-time step ~40 years after protection both inside and outside the protected area. Results: Long-term change in ecosystem service use outside the protected area on privately owned land of similar terrain to inside the protected area (Section 3): Over the last ~50 years, outside the protected area, there was a shift from livestock-based, subsistence agriculture and small-scale farming to a diversified set of ecosystem service uses. The combined area of grazing and wildflower harvesting declined by 39%, while the number of landowners using the mountains for personal nature-based recreation and ecotourism increased by 61% and 23% respectively. Agriculture intensified in suitable areas of mountain land with the number of landowners cultivating land increasing by 20%. Exogenous socioeconomic drivers associated with globalisation and economic growth were important causal mechanisms of land use change. Landowners valued mountain protection for intrinsic and non-use reasons (73-80% of landowners), including existence, bequest and option values, as well as for the indirect use of water supply (72% of landowners) in comparison with direct use reasons such as spiritual/cultural experiences and nature-based recreation inside the protected area (18 and 50% of landowners respectively). Personal, nature-based recreation outside the wilderness-protected area was associated with valuing the protection of mountain land for intrinsic and non-use reasons. Long-term vegetation change inside the protected area and plausible mechanisms driving vegetation change (Section 4): Inside the mountain protected area, fynbos vegetation cover increased on average between 11 and 30% and there were significant declines in bare ground and rock cover. In 5 accumulation and fire intensities. However, these latter changes in land use/cover also occurred outside the protected area (see results summarised for Section 3 above and Section 4 below) and therefore cannot be attributed to protected area establishment. Land use/cover and the influence on water flows inside the protected area compared to counterfactual scenarios of no protection (Section 5): Declines in grazing and changes to the fire regimes occurred regardless of the protected area boundaries. In the past, there was a high frequency of small, low intensity fires across the landscape, both inside and outside the protected area. More recently, fires have been actively suppressed and this resultsin the build-up of biomass and the development of extensive, high intensity fires which, under suitable conditions, burn large expanses of the mountain catchment. Hydrological modelling showed that a high intensity burning regime negatively affected streamflow regardless of protected area boundaries. Streamflow increased by more than 80% under high flow conditions and decreased by more than 40% under low flow conditions relative to an unburnt ‘natural’ scenario. Over the last 50 years there has also been a substantial increase in dams, buildings and roads and minor increases in cultivation outside the protected area. This has been avoided inside the protected area where these land use/cover classes declined. If the increase in these land use/cover types observed outside the protected area occurred inside the protected area this would have resulted in reductions in daily streamflow leaving the protected portion of the catchment. For example, outside the protected area reductions of 8% to 25% of streamflow were observed during mid and low flow conditions respectively, particularly during dry years, in comparison to a ‘natural’ scenario. In contrast, inside the protected area streamflow recovered from past conditions to more closely resemble the natural flow conditions of the catchment. Therefore, had the protected area not been established there would have been losses in streamflow from the catchment as well as an increase in the degree of fragmentation within this mountain area. However, with increased water storage and fragmentation outside the protected area has also come increased socio-economic opportunities such as employment and local opportunities for ecotourism and sustainable agriculture e.g. indigenous cut flows. This highlights the importance of maintaining various forms of land management systems (multifunctional landscapes) within mountain ecosystems but also the need to understand the sustainability of different land management system types. Determining appropriate land management systems for mountain areas should be based on a full understanding of the impacts on ecosystem service benefits and costs at local and regional levels between social groups both spatially and temporally. Broader significance: This thesis contributes to the conservation literature on two main fronts. Firstly, it contributes conceptually and theoretically to understanding the dynamics of ecosystem services in relation to mountain protection. Secondly, it contributes methodologically by using an inclusive, trans- and interdisciplinary research approach for evidence-based conservation at a place-based and landscape level. The study provides a case 6 study example of the positive impact that mountain protection has on water-related ecosystem services, notably by maintaining streamflow throughout high to low flow periods and during dry years. It also provides clear evidence that ecosystem service trade-offs do not remain constant over time and shows that intrinsic and non-use values are required when describing the importance of mountain protected areas. In terms of understanding the impact that protected areas have in mountain regions, the research shows that complex processes are at play that extend beyond the boundaries of a specific protected area in both time and space. Interactions between global and local drivers were found to be prominent causal mechanisms of socio-ecological change and ultimately determined the influence of mountain-protection on land use/cover, fire, vegetation and water-related ecosystem services. The thesis emphasises that counterfactual framings are necessary to understand and attribute the impacts of protected areas on environmental outcomes, however pluralism and socio-ecological approaches are critical to determine plausible counterfactual conditions. This thesis focused only on landowners adjacent and proximal to the protected area owning the majority of mountain catchment land of similar terrain. It is likely that multiple socioeconomic trade-offs have occurred between different social groups and generations at both local and regional levels. Understanding how the disadvantages and benefits of the impacts of protected areas are apportioned across the landscape and temporally is an aspect that requires future research. Central to this would be to fully consider how human well-being is influenced both upstream and downstream, including at regional levels, and between social groups and across generations. Considering the impact of protected areas on the full range of ecosystem services and linking this to societal preferences and perceptions should be incorporated into the overall goal of developing an evidence base for conservation. This is because it is both scientific evidence and societal change that can determine protected area persistence and thus long-term protected area impact.

In this study, I aim to understand business responses to social-ecological grand challenges. Prior research has suggested that problem identification and attribution help to foster meaning and action on societal issues. In particular, framing theory has offered significant insight into individual actors' cognitive processes, their skillful articulation of socially resonant interpretive frames, and the role of particular actor categories and repertoires in framing success. At meso and macro levels, researchers have tended to focus on social movements and the outcomes of highly charged political contests between these groups and state actors. As such, we know far less about the co-creative mechanisms and contextual ‘raw materials' that underpin meaning making activities and interaction between groups, especially in instances where the focus is on firms and the significance being attached to ambiguous societal issues for which they are not directly responsible. A key outstanding question is therefore: how do firm-internal agents interpret, signify and mobilize organizational responses to grand challenges? In an effort to address these lacunae, this study explores the proactive efforts of three firms to interpret the complexity of social-ecological grand challenges that they share with the rest of society and to address these issues through meaningful and mitigating action. My inductively derived theoretical model of ‘interactional framing for issue advancement' shows how the active engagement of external influences by internal change or ‘signifying agents' facilitates action on grand challenges within and beyond the firm. While framing activities charge grand challenge issues with meaning and help to organize actors' understanding of, experience, and action around these issues, material affordances and interaction with external actors provide the enabling environment for resonant interpretations to take hold and to facilitate enactment. Grounded in my cases, the model also depicts the progressive sequencing of signifying agent efforts across three broad stages: Introduction and Disruption, Experimentation, and Enactment. My analysis contributes to the management literature by suggesting that the signification work of firm-internal agents is a process of mediation, shaped by the distinct and emergent character of grand challenges and the interplay of social and material mechanisms. Because such issues require a greater emphasis on problem-solving and novel sources of information, my account contrasts with conventional representations of meaning-making as a relatively straightforward line of action from individual logics ‘pulled down' from institutional systems and packaged attractively to appeal to ‘outsiders' less involved in the processes of signification. It also provides an alternative to the popular view of meaning construction as a ‘contest' or essentially dispute-oriented process. Instead, I argue that grand challenge issue advancement demands a more intricate, interactional and contextual process of meaning-making by interested actors and issue proponents internal and external to the firm. The model of signification work I offer in this study thus more fully captures the perspective that actors do not simply assess and attach importance to complex issues, but construct the very nature of the issue itself, and that this construction is a precursor to collaborative action on grand challenges.

0 / SPK / specialcollections@tulane.edu