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Coastal fishermen and whalers on the island of Qeqertarsuaq in Disko Bay, west Greenland, rely on the harvest of marine resources for the continuation of subsistence livelihoods. Over the years, however, Qeqertarsuarmiut have witnessed increasingly stringent whaling quotas and, more recently, a global crisis-narrative about climate change which ignores the reality of coastal livelihoods in the Arctic. In popular debates about whaling, aboriginal subsistence whalers (ASWs) are generally portrayed as 'uncivilised' while the climate crisis-narrative features arctic coastal dwellers as somehow more 'exposed' or 'vulnerable' to environmental fluctuations than the rest of the world. Qeqertarsuarmiut tell a different story about their relationship and ways of engaging with non-human persons (such as winds, sea ice and marine mammals) as these are encountered in the course of seasonal harvesting efforts along the coast and wider bay waters. So while ecological fluctuations have certainly been observed, interactions with a familiar coastal environment continue to foster a relationship that presupposes a sense of patience and flexibility towards shifting sea ice conditions, local weather vagaries and the moods of non- human persons and forces. Coastal dwellers attentiveness towards the liveliness of fiords, mulls and inlets is anchored in stories about both previous encounters, and contemporary experiences, with wilful environmental agents, which reflect an enduring ontology of openness towards the sea. The chapter argues that coastal - as opposed to crisis - narratives about Qeqertarsuarmiut seascape making reflect the complexities of arctic livelihoods in ways that conflict with imposed whaling regulations and the otherwise dominant vocabulary of risk associated with climate change in the Arctic today.

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A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg in fulfilment of the requirements for the degree of Doctor of Philosophy, 2017 / Plant phenology, the study of the timing of biological events such as leaf flush, has been identified as a key tool in monitoring and understanding the impacts that changing climates may have on the world. Unfortunately there is a noticeable lack of phenological research in Africa’s savannas in comparison to other global ecosystems, such as temperate forests. Savannas are known for their complexity in structure and composition and the phenology of their flora is no exception to this. Owing to the highly seasonal climates in this system, plants have had to evolve a range of phenological strategies to cope with the limited window of suitable growth conditions during the periodic wet season in the austral summer. One of these phenological strategies is that of early-greening; where deciduous trees will produce new flush prior to the onset of seasonal rainfall when the environmental conditions are at their driest. There is likely no other ecosystem in the world where the early-greening phenomenon occurs, however, it has been recorded in savannas from Africa, Australia, Asia and South America. The global prevalence of this strategy suggests that early-greening trees must gain some benefit from utilising this seemingly risky leaf flushing strategy. The main aim of this study was to investigate two of the hypothesised benefits of an earlygreening strategy for semi-arid savanna trees. The first hypothesis suggested that earlygreeners are extending their growing season beyond that of grasses and late-greeners – whose leaf flush is limited by the availability of water through the onset of seasonal rainfall. The second hypothesis is that early-greeners produce new leaves ahead of the emergence of invertebrate herbivores with the onset of the first rains, therefore decreasing the risk of damage to the vulnerable tissues and allowing the defence mechanisms within/upon the leaf to develop. This study took place in the Nylsvley Nature Reserve (NNR) over three consecutive austral growing seasons (August 2012 to April 2015) and was conducted on the two dominant deciduous broad-leaved trees: Burkea africana and Terminalia sericea. Burkea africana is known to flush prior to the onset of seasonal rainfall and was considered the earlygreening species in this study. Terminalia sericea has been recorded as flushing leaves prior to the onset of rainfall, but is more often a facultative-greener – rapidly producing new leaves with the onset of seasonal rainfall. This study experienced high seasonal variability between years with early-greening only occurring during the final (2014-2015) season. Nevertheless, I was able to assess the weekly green-up phenology of both species during the first three months of green-up and found that the green-up of the trees was largely disconnected from the main system driver – water – while grass green-up was closely linked to the onset of rainfall. This complements the theory of temporal niche separation; however, when assessing the functionality of the new leaves produced, carbon gain only occurred after the first two weeks post bud-break. In a system such as the NNR where rainfall onset variability is high, trees will only gain the advantage of an extended growing season if the onset of rainfall is more than two weeks after the start of flush. Using historical rainfall records (1980-2014), I estimated that 46% of years could have potentially experienced early-greening with rainfall commencing after the 15th October – the earliest date of green-up prior to rainfall onset in the NNR during this study. One of the benefits tested relating to early-greening in this study was that early-greeners avoid invertebrate herbivore damage on vulnerable new leaves. This study provided evidence for the use of a phenological defence strategy to cope with invertebrate herbivory pressure. Leaves which emerged before the rains had lower rates of herbivore damage than those which emerged after. Moreover, it was demonstrated that the constant turnover of leaves with high photosynthetic rates (T. sericea) is a reasonable mechanism for dealing with high leaf herbivory, and can result in equivalent end of season leaf area (and carbon gain) to species which invest in defence and have slower turnover rates (B. africana). Using the ground-based phenological measures in conjunction with remotely sensed NDVI imagery, the frequency of early-greening across seven comparable broad-leaved woodland sites in southern Africa from 2002 to 2014 was quantified. Of the environmental variables considered, the predictability of early-season rain (rather than total rainfall amount) was best correlated with early-greening. In savannas where rainfall onset and annual amounts were highly variable (such as the NNR), early-greening was less frequent (20% of the years) while in savannas closer to the equator where rainfall amounts were consistently >900 mm per annum and the onset dates began within a two week window each season, early-greening occurred in 80-90% of all years. The decrease in the proportion of early-greening events in the NNR from the 1980s to the past decade could be driven by the changing rainfall regimes over South Africa – with a predicted decrease in the number of precipitation events, but an increase in the storm intensity and rainfall amounts in each of these events. Fewer precipitation events may increase the risks associated with the early-greening strategy and this may be driving the NNR trees to use this strategy less frequently. This study has highlighted the need for a long-term phenological monitoring network within southern Africa’s savannas and has illustrated how early-greening species can benefit over other flora when environmental conditions are suitable for them to commence early leaf flush. This thesis has shown that early-greening broad-leaved savannas trees in South African savannas are more likely to avoid invertebrate herbivory than extend their growing seasons. / XL2017

Thesis advisor: Thanh V. Tran / Research has established that dietary quality among Asian immigrants declined after immigrating to the United States, indicated by decreasing intake of healthy food and increasing intake of unhealthy food. There is a need for a broader investigation for the interactive influence of acculturation, sociodemographic and environmental factors on dietary intake among this population. Guided by the Operant Theory of Acculturation, and the Dietary Acculturation Theory, the present study examined the following research questions to address the gaps in the literature: (1) Are acculturation factors associated with dietary intake among Asian immigrants? (2) What sociodemographic factors are associated with dietary intake among Asian immigrants? (3) What environmental factors are associated with dietary intake among Asian immigrants? (4) What sociodemographic factors moderate the effect of acculturation on dietary intake among Asian immigrants? (5) What environmental factors moderate the effect of acculturation on dietary intake among Asian immigrants? The data in use come from the 2011 – 2012 Adult California Health Interview survey. The sample includes 2,122 non-Hispanic Asian adults born out of the United States. Results from negative binomial regression indicate that intake of fruits, vegetables, soda, fries and fast food was all negatively associated with living in the United States for at least 10 years, compared to living in the Unites States for less than 10 years. The present study also found sociodemographic (including ethnicity, age, gender, education, employment status, and income) and environmental factors (including family type, household size, household tenure, housing type, perceived availability of fresh fruits and vegetables, residential area category, and participation in food stamp and WIC) statistically significantly confounded and moderated the association between length of time lived in the United States and dietary intake. Findings from this study extend the understanding of the protective and risk factors for Asian immigrants to develop and maintain healthy diet, and demonstrated the complexity of dietary changes among Asian immigrants. Based on the findings, the importance that social work research and practice in addressing nutrition inequality among Asian immigrants was highlighted. The study also discovered potential issues and challenges of developing measurement for dietary intake among Asian immigrants, and provided empirical evidence of longitudinal research designs to further explain dietary changes, and guidelines for community-based interventions to address strategies of nutrition promotion among Asian immigrants. / Thesis (PhD) — Boston College, 2017. / Submitted to: Boston College. Graduate School of Social Work. / Discipline: Social Work.

A research report submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Science. Johannesburg, 2017. / Lesotho, being a mountainous area and due to the level of poverty and the dependency of its economy largely on agriculture, is particularly vulnerable to the impacts of climate change. This study examined maximum, minimum and mean temperature trends at various altitudes in Lesotho so as to determine possible implications of recent (70 - 80 years) altitudinal climate trends on the agricultural sector. Using seven stations at various altitudes across Lesotho, trends in maximum, minimum and mean temperatures were analyzed at monthly, annual and seasonal scales. The significant warming of minimum temperatures (Mokhotlong (p=0.000), Oxbow (p=0.013) and Qachasnek (p=0.002)) and maximum temperatures (Mokhotlong (p<0.0001), Oxbow (p=0.007) and Qachasnek (p=0.000)), were observed at the highland stations, located on the eastern side of Lesotho, while at the lowland stations as well as in the foothills, located on the western side of Lesotho, significant increases were only observed with minimum temperatures (Maseru (p<0.0001) and Mejametalana (p=0.000), Butha Buthe (p=0.017), located on the western side of Lesotho. In Mohaleshoek, located in the Senqu river valley, no significant trends were observed. In addition, a significant decrease in the number of days with frost was observed in both the highlands and the lowlands. With significant increases in maximum and minimum temperatures, a decline in agricultural production can be expected in the lowlands while a potential increase in areas suitable for agricultural production can be expected in the highlands. / LG2017

A thesis submitted to the Faculty of Science in fulfilment of the requirements for the degree of Doctor of Philosophy. 30 August 2016 in Johannesburg, South Africa. / The presence of Portulacaria afra affects the flow of ecosystem services from the thicket landscapes of the Eastern Cape. Degraded and intact thicket ecosystems deliver different bundles of ecosystem services, and within each bundle the services are linked non-linearly, so that land-use and management decisions which seek to increase a particular service affect the delivery of other services. One of the challenges of restoring the historically degraded thicket areas is understanding the trade-offs between various objectives, including re-establishing biodiversity and critical services such as carbon sequestration, climate regulation, water provision and forage supply. This thesis uses a variety of techniques to assess some of these trade-offs at several spatial and temporal scales. The amount, rate and nature of carbon assimilation by P. afra at a variety of spatial and temporal scales are also explored. Methods At a landscape scale stream flow data from transformed and intact catchments, near Jansenville and Bucklands respectively, are used to compare the freshwater ecosystem services provided by the presence of P. afra. Similarly, at a landscape scale, the new high resolution Multi-angle Imaging SpectroRadiometer (MISR-HR) products are used to explore the differences in the surface energy budget of intact thicket and degraded ecosystems. Two simple radiative transfer models are used to assess the radiative forcing (RF) trade-off between carbon uptake-related global cooling and albedo-related global warming. From samples and measurements taken from a field site 15 km south-west of the town of Kirkwood, radiocarbon and stable carbon isotope analysis, growth ring analysis, dendrometry, infrared thermometry, water use efficiency and eddy covariance data are used to quantify the rate of carbon assimilation by P. afra, and unpack the contribution of C3- and CAM-derived carbon to total carbon sequestration. Results Intact thicket cover results in a higher total yield of water as a fraction of rainfall, fewer extreme high flow events, and a higher volume of low-flow in comparison to landscapes thought to represent transformed former thickets. Intact thickets have a lower albedo than degraded thickets. Restoring to an intact state will result in a mean albedo decrease of 5% (absolute) which constitutes a direct radiative forcing of +0.019 pW m-2 at a global scale. This warming effect overwhelms the climate benefit derived from carbon sequestration related to P. afra growth by a factor of 1.6. The growth data suggests that P. afra produces two growth rings annually on average, with the average growth increment of 0.8mm in diameter. The multi-year and multi-source aboveground relative growth rate mean is 0.006 (±0.005 SD) g DM per g DM per year, which is mean average increment about 1.1% per year. The eddy covariance data highlighted the temporal variability in the system, measuring intact P. afra thicket vegetation as a net source of carbon to the atmosphere 0.018 gC m-2 hr-1, over the three short-duration campaigns. CAM is now understood to come in several variants. The sampled stems, averaged across all rings, had a δ13C signature of -15.8±1.0 ‰ indicative of “strong CAM” behaviour. P. afra plants in the Kirkwood locality over the past decades have derived 61% of their carbon through the CAM pathway and 39% through the C3 pathway, with substantial inter-stem variation. The soil isotope data suggests 51 - 63% C3 derived carbon, with values increasing with sampling depth. There are occasional large excursions, always in a single growth ring, towards more negative δ13C values (-19.0‰); in other words towards the C3 range. Although thought to be related to water stress, it was hard to determine a single trigger for the switching between C3 and CAM modes. This is consistent with findings for other strongly CAM plants. From the dendrometers and infrared thermometry, P. afra shows flexible stomatal behaviour on a range of timescales. For the majority of the study period the stomata were open both day and night. There is variation in stomatal closure over the year, which appears strongly seasonal, and suggests a link to the bimodal rainfall pattern experienced in the region. Using decision tree to classify the photosynthetic mode, this data suggest that the individual plants being measured are spending only 4% of the time in classical CAM mode, and the majority of the time in CAM-cycling. Conclusions Restoration of transformed thicket will improve freshwater ecosystem services associated with useful water yield, sustained supply, and flood control. It is important to include land-atmosphere feedbacks other than carbon assimilation when assessing the climate service delivered by restoration. The negative and positive radiative forcing will operate over different timelines. CAM metabolism plays an important but not exclusive role in carbon gain. Contrasting patterns between plant and soil C3 fraction may relate to allocation issues and the contribution by plants other than P. afra. The growth rates of thickets are not substantially greater than similar water-limited ecosystems. / LG2017

Peatlands contain a significant amount of the global soil carbon, but the climate feedback affecting carbon stability within these peatland systems is still relatively unknown. Organic matter composition of peatlands plays a major role in determining carbon storage, and while high latitude peatlands seem to be the most sensitive to climate change, a global picture of peat organic matter chemistry is required to gauge overall peatland stability and to improve models of greenhouse gas emissions fueled by soil carbon decomposition. The goal of this research is to test the hypothesis that carbohydrate content, an indicator of soil organic matter lability or reactivity, will be lower in carbon deposits near the equator and greater in high latitude peatlands. Conversely we hypothesize that peat aromatic content will be higher at low latitudes relative to higher latitudes. As a part of the Global Peatland Microbiome Project (GPMP), around 1400 samples of peat across a latitudinal gradient from 79N to 65S were measured with Fourier transform infrared spectroscopy (FTIR) to examine the organic matter functional groups of peat. Carbohydrate and aromatic content, as determined by FTIR, are useful proxies of decomposition potential and recalcitrance, respectively. A highly significant relationship was observed between carbohydrate and aromatic content, latitude, and elevation. Carbohydrate contents of high latitude sites were significantly greater than at sites near the equator, in contrast to aromatic content which showed the opposite trend. It was also clear that at locations with similar latitudes but different elevations, the carbohydrate content was higher and aromatic content was lower at higher elevations. Higher carbohydrate content at higher latitudes indicates a greater potential for lability and resultant mineralization to form the greenhouse gases, carbon dioxide and methane, whereas the composition of low latitude peatlands is consistent with their apparent stability in the face of greater temperatures. The combination of low carbohydrates and high aromatics at warmer locations near the equator could foreshadow the organic matter composition of high latitude peat transitioning to a more recalcitrant form with a warming climate accompanying the evolution of greenhouse gases. / A Thesis submitted to the Department of Earth, Ocean and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester 2018. / April 16, 2018. / Decomposition, FTIR, Latitude, Organic Matter, Peatlands, Stability / Includes bibliographical references. / Jeffrey Chanton, Professor Directing Thesis; Robert Spencer, Committee Member; Olivia Mason, Committee Member.

The cold blob refers to an observationally unprecedented, gyre-scale, record-breaking cold of mean surface temperature over the subpolar North Atlantic. Its anomalous cold feature goes against the rising trend of global mean surface temperature in the context of a warming climate. Observations show that the Atlantic cold blob emerged in early 2014 and can penetrate deeper into the ocean interior beyond 500m depths. A sudden drop in upper ocean heat content is associated with an accumulative increase in freshwater content. Prior works pointed out that intense surface forcing during two consecutive winters was a primary driver. We hypothesize that surface forcing alone is insufficient for the cold blob to persist. Our analysis shows, for the first time, that variations in the net surface heat fluxes cannot explain the decline in upper ocean heat content during 2014–2017. Therefore, surface forcing fails to explain the origin of the cold blob. To investigate alternative mechanisms, non-assimilative simulations based on a coupled ocean-sea ice model (GFDL MOM5/SIS1) with two different atmospheric forcings (MERRA2 and ERA-interim) are employed to examine the transports of mass, heat, and freshwater within the cold blob area. Initial diagnosis verified that both model runs can reproduce the cold blob characteristics at similar magnitudes to Argo observations. Model results show a decreasing trend of heat transport at the southern boundary, implying that reduced poleward ocean heat transport likely accounts for the formation and persistence of the cold blob. This cooling signal from the south is accompanied by a freshening signal. Changes in the residual heat fluxes suggest that reduced warming for the subsurface layer at 100–700 m depths apparently occurred since 2006 before turning into enhanced cooling during late 2013. Variations in the residual freshwater fluxes remain positive for the entire past decade and subsequently result in an accumulative surplus of freshwater content in this area. The model run with incorporated Greenland meltwater estimates sheds light on the relative contribution of meltwater advection. To a great extent, Greenland meltwater can amplify the freshening tendency in the subpolar North Atlantic by approximately up to 200% during the present decade. In the long run, upper ocean cooling and freshening would lead to increased stratification and reduced mixing with deeper waters, therefore enhancing the likelihood that the subsurface cold blob persists. / A Dissertation submitted to the Department of Earth, Ocean and Atmospheric Science in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2018. / November 5, 2018. / Air-Sea Interaction, Climate Change, Cold Blob, Greenland Meltwater, Polar-Lower Latitude Linkage, Subpolar North Atlantic / Includes bibliographical references. / Mark A. Bourassa, Professor Directing Dissertation; James B. Elsner, University Representative; Allan J. Clarke, Committee Member; William K. Dewar, Committee Member; Kevin G. Speer, Committee Member.