O desenvolvimento das atividades humanas está ocorrendo a um alto custo ambiental. A elevação das concentrações atmosféricas de CO2 e as mudanças no uso do solo estão desencadeando mudanças relevantes no clima global. O objetivo deste trabalho é determinar, por meio da largura dos anéis de crescimento, áreas de vasos e isótopos estáveis de carbono, como as espécies de jatobá: Hymenaea courbaril L. (de mata) e Hymenaea stigonocarpa Mart ex. Hayne (de cerrado) estão respondendo às mudanças do clima. Foram coletadas amostras do tronco principal de 12 indivíduos de H. stigonocarpa e 11 de H. courbaril. As amostras foram polidas e os anéis de crescimento foram identificados, datados e medidos. As cronologias foram construídas utilizando os programas COFECHA e ARSTAN. Com os anéis datados, foram medidas as áreas de vaso do lenho inicial de cada anel e também foram obtidas amostras de αcelulose dos anéis de crescimento para a análise de ∂13C e cálculo da eficiência intrínseca do uso da água (Wi). Os resultados mostram que, a largura dos anéis de H. courbaril sofre influencia positiva da precipitação, e negativa da temperatura, no final da estação de crescimento. Já as áreas de vaso são influenciadas positivamente pela precipitação do meio da estação de crescimento e negativamente pela temperatura da estação seca antes do início do crescimento. Para H. stigonocarpa, a largura do anel de crescimento sofre influência positiva da precipitação, e negativa da temperatura, durante a estação seca anterior ao início do crescimento. Já as áreas de vaso são influenciadas positivamente pela precipitação do início da estação seca anterior à estação de crescimento e negativamente pela temperatura no início do crescimento. Em relação ao ∂13C, as duas espécies mostraram uma influência do clima da estação de crescimento corrente e também da imediatamente anterior. Além disso, H. stigonocarpa possui uma tendência de elevação do Wi nas últimas cinco décadas que não foi encontrada em H. courbaril. Os resultados mostram que as espécies respondem a diferentes pressões ambientais, e isso levará a respostas diferentes em cenários de mudanças climáticas. Nesses cenários, as duas espécies podem ser prejudicadas, mas H. courbaril, possivelmente, sofrerá mais. Porém, existe outra pressão imediata sobre as espécies, que é o desmatamento. A análise das taxas de crescimento pode auxiliar as tomadas de decisão em projetos que envolvam supressão das matas e cerrados. Nesse contexto, H. stigonocarpa possui uma taxa de crescimento média 2.4x menor que a de H. courbaril, mostrando o maior tempo que essa espécie leva para atingir um tamanho maduro. / The development of human activities is taking place at a high environmental cost. The increasing atmospheric CO2 concentrations and changes in land-use are unleashing relevant changes in global climatic. The objective of this study is to determinate how H. courbaril L. (from forest) and H. stigonocarpa Mart ex. Hayne (from cerrado) are responding to the climatic change through tree-ring width, vessel area and stable carbon isotope analysis. Twelve specimens of H. stigonocarpa and eleven of H. courbaril were sampled. Then, samples were polished and tree-rings were identified, dated, measured and chronologies were built using COFECHA and ARSTAN softwares. With tree-rings dated, early wood vessel areas were measured and α-celluloses were sampled from wood of each tree-ring to ∂13C analysis and intrinsic water-use efficiency estimation (Wi). The results shows that tree-ring width in H. courbaril are positively related with the precipitation, and negatively related to temperature, during the end of growth period. Also, vessel areas are positively related to precipitation during the middle growth period and negatively related with temperature during the dry season previous to growth period. Tree-rings width in H. stigonocarpa were positively related to precipitation during dry season previous to growth period and were negatively related to temperature during the same period. Also, vessel areas were positively related to precipitation during the beginning of dry season, previous to the current growth period, and negatively related to temperature during the beginning of growth period. In relation to ∂13C, climate signals were found during the current growth period and the previous one. Beyond that, H. stigonocarpa showed a clear increasing trend on i during the last five decades, that was not found in H. courbaril. The results indicate that these species respond to different environmental demands, and that shall lead to different responses regarding the climatic change scenarios. In these scenarios, both species shall be negatively influenced, which will be probably worse in H. courbaril. But, there is another immediate pressure on both species that is related with deforestation. The growth ratio analysis can help policy-makers in projects that have forest and cerrado suppression. In this context, H. stigonocarpa has a mean growth ratio 2.4x smaller than H. courbaril, what implicates longer time for those species reach a mature size.

O coletivo tupi Tembé-Tenetehara da Terra Indígena do Alto Rio Guamá iniciou em meados de 2006 diversos processos de negociação envolvendo projetos no mercado de crédito de carbono. O presente texto analisa essas conexões inserindo-as na concepção nativa dessas relações. A análise enfatiza as divergências cosmográficas implicadas, apresentando um modelo da arquitetura do cosmos tembé a partir do corpus mitológico nativo, dos estudos de astronomias indígenas, das pesquisas sobre xamanismo e do multinaturalismo pan-ameríndio. / In mid-2006 the collective Tupi Tembé - Tenetehara from the Indigenous land of the Alto Rio Guama began various negotiation processes involving projects in the carbon credit market. This thesis examines these connections placing them in the native view of relationships. The analysis emphasizes the implied cosmographic differences, presenting a model of the Tembé\'s cosmos architecture based on the native mythological corpus, studies of indigenous astronomy, research on shamanism and the pan-Amerindian multi-naturalism.

Magister Artium - MA / Wetlands provide various ecosystem services such as provisioning, regulating, supporting, and cultural services which may be directly or indirectly beneficial to humans. The manner in which such wetlands are managed is partly determined by human perceptions of their value. However, climatic variability and climate change put the continued provision of such ecosystems under stress. The result is that certain ecosystem services may be provided to differing extents during anomalously wet or dry years. There is thus uncertainty as to the values ascribed to wetlands by people during varying climatic phases. This thesis focuses on understanding how people perceive the functioning of wetlands within our current climate against a background of climatic variability and climate change. This study explores people’s perceptions regarding the functioning of wetlands and ecosystem services provided during dry and wet years, as an indication of how climatic variability and climate change impact peoples’ perceptions. The data was collected in the wetlands of the Agulhas Plain in the Nuwejaars Catchment. Five wetlands classified and scored using the WETEcoServices tool. In addition, five semi-structured interviews and three participatory mapping exercises with landowners were also undertaken. The study reports on the landowners’ awareness of wetland ecosystems, ecosystem services and climatic variability and climate change. Provisioning, supporting, and cultural ecosystem services are frequently used by landowners, which can be impacted by climatic variability and climate change. The WETEcoService benefits and landowners perceptions of ecosystem services varies, as the WETEcoService direct and indirect ecosystem services are either effective or ineffective in dry and wet years. In contrast to landowners perceptions emphasising the importance of ecosystem services directly beneficial to them. The study recommends that the ecosystem services landowners perceive as important is linked to their interest to guarantee their participation in catchment management. WET-EcoService benefits can inform landowners and managers about ecosystem services degradation and whether their conservation methods are either positively or negatively impacting wetlands.

Climate change and the accompanying increase in global surface temperatures pose a major threat to freshwater ecosystems, especially at high latitudes where warming is predicted to be particularly rapid. To date many aspects of how rising temperatures can impact fresh waters remain unknown. Information about temperature effects on the level of communities, food webs, ecosystems is especially scarce. The few studies focusing on higher levels of organisation have used either laboratory microcosm experiments, which can lack realism or space-for-time substitution across large ranges of latitude, which can be confounded by bio-geographical effects. This study aimed to overcome these shortcomings by using a “natural experiment” in a set of 16 geothermally heated streams in the Hengill area, South-West Iceland, with water temperatures ranging from 4ºC to 49ºC (mean temperature). Data were analysed for two seasons, August 2008 and April 2009. The principal goal of this study was to assess the effects of temperature on the structure and functioning of food webs. Additionally the persistence of the community structures along the temperature gradient was examined through time (comparison of previously collected data in August 2004 and August 2008). Abundances of cold-stenotherm species decreased whereas those of eurythermal species increased with increasing temperatures leading to knock-on effects on abundances of other species. Species community overlap between streams declined as temperature difference between streams increased. The persistence of species composition through time was weakened at the extremes of the temperature gradient. Food webs showed a clear size structuring in analyses of trivariate food webs, abundance and biomass size spectra. Analysis of connectance, complexity, mean link length, mean 2-span, mean community span and slopes and intercepts of linear regressions fitted to the trivariate foods or size spectra revealed the impact of temperature change on freshwater ecosystems.

Climate change can have potentially catastrophic effects upon biodiversity and food web structure and according to the fourth IPCC report, ambient temperatures will rise by between 3.0-5.0 °C over the next century, with already an average increase in global surface temperature of ~0.74°C in the past 100 years. This has known implications in ecology from individuals to ecosystems. The microbial loop consists of small organisms ranging in body size from bacteria (1-15 μm), single-celled eukaryotes (10-1000 μm) and multicellular organisms (250 – 1000 μm) that assimilate dissolved organic carbon into the “classical food web”. ! The principal goal of this thesis was to assess how rising global temperatures might impact the natural microbial assemblages in 20 mesocosms under 2 treatments – 10 warmed (in line with IPCC predictions) and 10 ambient. The abundance and body mass of 4 major microbial loop taxa (desmids, flagellates, heterotrophic protists and meiofauna) were quantified at monthly intervals over a 2-year period. Secondly, in a microcosm experiment, the population dynamics of three pure cultures of ciliates were monitored across a temperature gradient; the rate of population decline under starvation and changes in body size were quantified.! Results showed that (1) rising global temperatures alters the size spectrum in the autotrophic protists, (2) temperature interacts with temporal and spatial gradients, resulting in changes in phenology (3) these changes in phenology are observable at both the community level and the population level within the microbial assemblage of the mesocosms and (4) extinction rates and body mass reduction in experimental microcosms were faster at warmer temperatures and partially support predictions of the metabolic theory of ecology.! The implications of these findings are discussed in terms of (1) continued research into the role that small organisms play in community and ecosystem ecologyand (2) the use of these small organisms in experiments as models to inform ecological theory by scaling up from microcosms and finally, (3) I discuss future directions in freshwater microbial ecology, focusing on the increased use of molecular techniques.

Many people view climate change as one of the top issues facing the world today. As a result, a better understanding of how climate change messages are communicated has become increasingly important. Additionally, with the progression of today’s society into that of highly-visual culture, opportunities for the investigation at the intersection of climate change and visual content would be of great benefit to academia and society, as a whole. More specifically, providing insight into how climate change visuals are framed and what their relationship is to emotions would support visual framing theory and present opportunities to strengthen climate change messaging in the future. Taking a quantitative approach, this research deploys experimental design to test hypotheses and answer research questions on the relationships among three climate change visual frames (causes, impacts, solutions), emotional experience, and climate change salience. In addition, to attempt to provide further insight into these relationships, the personality traits neuroticism and extraversion are tested as moderators. A sample provided from Amazon Mechanical Turk (n = 289) was evenly disturbed between three experimental conditions, each representative of one of the climate change visual frames. Statistical analysis was then utilized to generate results in response to hypotheses one thru eleven and research questions one and two. The findings from this study show that climate change visual frames each generate specific emotional experiences upon viewing. The causes and impacts climate change visual frames result in a negative emotional experience, while the solutions climate change visual frame generates a positive emotional experience. However, this research found no support for the personality traits neuroticism or extraversion playing a role in that response. Similarly, there was no connection found between emotional experience and climate change salience. The findings of this research, however, ultimately support the effectiveness of climate change visual frames without their traditional accompanying text, in the form of a caption or story, and contribute to visual framing theory. Considering the effectiveness of stand-alone climate change visual frames in generating positive and negative emotional experiences can prove useful for practitioners in the creation of future climate change content.

Achieving the Scottish Government's carbon reduction targets requires not only the decarbonisation of industry and electricity generation, which is now largely underway, but also significant changes in the actions and decisions of millions of individuals, whose carbon emissions fall outside the areas which Government can control. Transport, much of it undertaken by individuals, accounts for around 20% of Scotland's carbon emissions. Policy aimed at changing individual travel behaviours will therefore become increasingly important. Commonly applied behaviour change strategies based on rational actor theory face conceptual problems and cannot overcome the lack of agency experienced by individuals buffeted by a range of influences in a complex world. Practice theory relocates the site of analysis from the individual to the social and helps to overcome these problems, but it is not clear how to deliberately change practices to achieve the carbon reductions required. Understanding practices as emergent properties of complex social systems suggests that working to alter the complex social system may lead to different emergent properties, i.e. more sustainable practices. My research explored this approach by conducting an experiment in Aberdeen that sought to influence the complex social system within which audiences travel to a large theatre in the city. Emergent properties of the system encouraged travel by private car: problems of (in)convenience and insecurity were shaping individuals' travel practices. Collaboration between actors powerful enough to affect the system - a transport provider, a local authority and the theatre itself - was needed to influence it sufficiently to bring about a change in the main travel mode from private cars to public transport. Analysis of this case identifies the need to acknowledge the relevance of complexity theory when developing carbon reduction policy. Perverse incentives encouraging public organisations to focus on their own 'direct' carbon emissions need to be replaced with a duty to collaborate with others to reduce society's overall carbon emissions. Those making policy and those implementing it will therefore need to understand and apply complexity theory, and will need highly developed skills in managing long-term collaborative projects rather than 'delivering' one-off changes. These attributes may be found in practitioners from diverse and less obvious fields, including the cultural sector.

Atmospheric concentrations of surface ozone (O3) are strongly affected by deposition to the biosphere. Deposition processes are very sensitive to turbulence, temperature, relative humidity and soil moisture deficit and are expected to respond to global climate change, with implications for both air quality (e.g. human health) and ecosystem services (e.g. crop yields). In this PhD study, the global chemistry aerosol model UKCA (United Kingdom Chemistry Aerosol model) dry deposition scheme was thoroughly investigated. Some errors in the existing implementation of the current UKCA stomatal resistance and in-canopy aerodynamic resistance terms for O3 and NOw (NO2, PAN, PPAN, MPAN) were identified and corrected (WES scheme). These model corrections led to a decrease of the total annual dry deposition of -150 Tg(O3) yr-1 (-13%) which brings UKCA more in line with multi-model inter-comparison estimates. This was associated with a large increase of surface O3 concentration over land in the Northern Hemisphere (NH) with values up to 12 ppb (+50%) higher on annual average. Many studies have shown that O3 stomatal uptake by vegetation, which is the pathway leading to damage, accounts for 40-60% of total deposition on average. The remaining non-stomatal deposition flux is to external foliar surfaces, and soil. A more mechanistic non-stomatal dry deposition approach along with a scheme to simulate the effect of moisture on foliar surfaces on the stomatal transport (ZHG scheme) was introduced in UKCA to study the relative contributions of O3 flux occurring to stomatal and non-stomatal pathways at the global scale, and to explore the sensitivity of simulated surface O3 and O3 deposition flux. The ZHG scheme, led to significant changes in the O3 dry deposition velocity (Vd) (+40% in the North Hemisphere over boreal forests and -30% over tropical regions on annual average). The results of this study show that the ZHG scheme significantly changes the partitioning between stomatal and non-stomatal O3 flux. The non-stomatal fraction increased throughout the year and considerably during the cooler season and in spring (with maxima values by up to 60% for C3 grass and by up to 70% for needle leaf trees). The performance of both UKCA dry deposition schemes were compared with measurements, focussing on the diurnal and seasonal variations of the dry deposition velocity terms and the partitioning of O3 fluxes between stomatal and non-stomatal sinks. Overall, both UKCA dry deposition schemes capture the diurnal variations of Vd reasonably well. However, this study highlighted difficulties in comparing large grid (~280 x 390 km at mid-latitudes) averaged modelled values with site and vegetation specific characteristics of the measured exchange processes (~1 km2) and the driving meteorological variables. These differences in scale are a large source of uncertainty in the comparison of measured and modelled O3 Vd. Off-line simulation tests conducted on the non-stomatal deposition component with the ZHG scheme demonstrated the importance of modelling some key environmental and meteorological factors accurately (e.g. relative humidity, friction velocity, leaf area index). This was found to be crucial in order to improve O3 Vd model performance as well as improving the representation of specific vegetation properties. A comparison of the modelled global surface O3 concentration against observations both in the NH and SH revealed that the model performs well in the NH using both schemes, capturing the observed surface O3 cycle and the absolute values. The ZHG scheme led to a reduction of the annual bias (up to -13.5% on average) in the NH monitoring sites considered for this study. This is associated with a decrease in O3 deposition simulated with ZHG (as much as of -20% on annual average). By contrast, the seasonal cycle and absolute values of the observed surface O3 are not well reproduced by the model across the SH monitoring sites used in this study and a larger bias was found using the ZHG scheme (60% on average) compared to WES scheme (47% on average), as a consequence of an increase in O3 deposition (as much as of +20% on annual average) calculated with ZHG. A future climate integration for the 2090s using RCP 8.5 scenario was used to investigate the response of UKCA modelled O3 to climate change. The effect of climate change (by altering only the GHG concentrations predicted with RCP 8.5) on the dry deposition sink of O3 was addressed contrasting the two non-stomatal deposition parameterizations, and ignoring the changes in land-use and anthropogenic emissions. The study showed that O3 Vd over land declines from 2000 to 2100, and most strongly over vegetated areas (up to -24% over S. America, -17% over N. America and -10% over Europe). Climate change led to an increase of surface O3 concentration over land (by up to 20%). Whilst the two schemes behave similarly, and an increase in turbulence has been identified as the main driver, the decrease in land Vd is generally stronger in ZHG. This effect is more important over N. America and Eurasia where ZHG exhibits larger differences in deposition compared to WES as a result of changing climate. The increase in surface O3 over Arctic and Antarctic regions shows the effect that changes in O3 deposition might have on the long-range transport of O3. Finally, the influence of climate change on the partitioning of the O3 deposition flux was examined. This analysis revealed that more O3 is predicted to deposit through stomatal pathways with ZHG over N. America, C. Europe and E. Asia (up to +30%) compared to WES as a result of changing climate. Given that ZHG scheme captures the influence of meteorology and changing climate on surface O3 better than WES, it was concluded that modelled surface O3 using ZHG scheme showed a larger sensitivity to a changing climate than WES. These results imply potentially important effects of climate change on tropospheric O3, degrading air quality through the later decades of this century.

As part of the response to the threat of dangerous climate change a variety of methods have emerged for measuring greenhouse gas emissions to the atmosphere, assigning responsibility for those emissions, and informing decisions on mitigation actions. Many of these greenhouse gas accounting methods have developed in semi-isolated fields of practice, and this raises questions about how these different methods relate to each other, and whether they form ‘families’ of conceptually similar approaches. A useful distinction has developed within the field of life cycle assessment (LCA) between attributional and consequential methods, and this thesis explores the possibility of extending that distinction to categorise other forms of greenhouse gas accounting. Broadly, attributional methods are inventories of emissions/removals for a defined inventory boundary, while consequential methods aim to estimate system-wide changes in emissions that result from a decision or action. This thesis suggests that national greenhouse gas inventories, city inventories, corporate inventories, and attributional LCA are all attributional in nature, while project-level assessments, policy-level assessments, and consequential LCA are all consequential in nature. The potential benefits from creating this categorical framework include ensuring that individual methods are conceptually coherent, transposing lessons between methods of the same categorical type, and ensuring that the correct type of method is used for a given purpose. These various benefits are explored conceptually through the analysis of existing greenhouse gas accounting standards, and also empirically with the use of a bioenergy case study. The findings suggest that the attributional-consequential distinction is highly useful for conceptualising and developing greenhouse gas accounting methods, which is important, ultimately, for addressing dangerous climate change.

Understanding the impact of warming on organisms, communities and ecosystems is a central problem in ecology. Although species responses to warming are well documented, our ability to scale up to predict community and ecosystem properties is limited. Improving understanding of the mechanisms that link patterns and processes over multiple levels of organisation and across spatial and temporal scales promises to enhance our ability to predict whether the biosphere will exacerbate, or mitigate, climate warming. In this thesis, I combine ideas from metabolic theory with a variety of experimental approaches to further our understanding of how warming will impact photosynthesis and respiration across scales. Firstly, I show how phytoplankton can rapidly evolve increased thermal tolerance by downregulating rates of respiration more than photosynthesis. This increased carbon-use efficiency meant that evolved populations allocated more fixed carbon to growth. I then explore how constraints on individual physiology and community size structure influence phytoplankton community metabolism. Using metabolic theory, I link community primary production and respiration to the size- and temperature- dependence of individual physiology and the distribution of abundance and body size. Finally, I show that selection on photosynthetic traits within and across taxa dampens the effects of temperature on ecosystem-level gross primary production in a set of geothermal streams. Across the thermal-gradient, autotrophs from cold streams had higher photosynthetic rates than autotrophs from warm streams. At the ecosystem-level, the temperature-dependence of gross primary productivity was similar to that of organism-level photosynthesis. However, this was due to covariance between biomass and stream temperature; after accounting for the effects of biomass, gross primary productivity was independent of temperature. Collectively, this work emphasises the importance of ecological, evolutionary and physiological mechanisms that shape how metabolism responds to warming over multiple levels of organisation. Incorporating both the direct and indirect effects of warming on metabolism into predictions of the biosphere to climate futures should be considered a priority.