京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第17964号 / 農博第2032号 / 新制||農||1019(附属図書館) / 学位論文||H25||N4808(農学部図書室) / 30794 / 京都大学大学院農学研究科農学専攻 / (主査)教授 白岩 立彦, 教授 奥本 裕, 教授 稲村 達也 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

No description available.

How many inhabitans do have your city? Tuvalu has 12.000 and that´s not a city. It´s a country. Nine islands in south Pacific nearly date line. On first sight You may say, it´s a paradise. Air has always about 30°, sand is white, sky is blue and the sea is full of fish. On shore grows coconuts and on the sea-floor grows beautiful corals. But second lowest country in the Word cannot be a paradise. The land is missing in huge Pacific. Inhabitans don´t have money neither for build another Venice nor dubai´s palm. Global warming a sea level rise is dangerous for milions people of our planet. Maldives, Banghlades, Holland, south of USA… Many of you can have a question: „Why then Tuvalu?“ Few tausends people can move to Australia and finish. And Maldives have worse position, land has less meters over sea level, people is more… ten times. But 12.000… it´s so enough – for specimen. It´s enough people to get for them money and spend it for saving thein land, for trying some science theories. If cannot save these 12.000, you cannot save the others. They have many renewable resourcies: the wind is blowing, the sun is shining, the water is flowing. In this time they are maybe not energy-independent, but they plan to be in 2020. Energy is that wonderfull power, which can save them. Did you know, that if you set low electric energy going in iron element under sea level (which cannot harm sea life and people), at the surface is formed a layer of sediments called „biorock“?- rock, which can you use for building. The project will save only one atoll: Funafuti. It´s enough large for all contemporary and future inhabitans to living. Project is planned to year 2200 and calculated for 24.000 inhabitans. Untilll then sea level rise will grow about one meter above. On atoll Funafuti will rise eight villages with max. 3.000 inhabitans. Every village will have by average equipment (grocery, school, doctor, church) advanced nation-wide important functions (airport, hospital, parliament, university..). On biorock layer stored up in the sea by atoll Funafuti will rise shelf, where people can build stilt houses, how they did houndreds years before European arrival. Or they can live in houseboats. Between houses they wil build jetty road for light engine vehicles and bridge-like paths for pedestrians. They will meet on squares and over their heads will bloom tropical plant in colourfull steeltubes made for it. On the dry land, which is very small, will grow coconut and pandanus. This land will be under heritage, park for everyone to come end enjoy. Part of this project is a floating church. Its building represents all ideas, that Project Tuvalu has: building on water, energy-independent, offer an shelter, shade and place for meeting of people. White facade made from textile membrane reminds white sails of ships, that crossed oceans before 200 years. With these ships came Chrisitanity, that is deeply rooted in this land. Bamboo construction with steel cables will reminds to people Crown of Thorns and martyrium of Christ, but also average problem hat must people meet in their lives. This project is pure utopic and doesn´t have ambition to get real. Its aim is to make visible problem of global warming in this sight and create a discussion: what next?

A large disconnect exists between the general public's acceptance of human-caused climate change and the prevailing consensus of actively publishing scientists. Previous research has examined both political and economic motivated reasoning, media influence in print and television, conspiracy ideation as a predictor of science rejection, and the role of the social construction of scientific knowledge in science rejection. Using these previously studied justifications for climate change rejection as a starting point, this research examines 212 written responses to a prompt at Climate Etc. asking the community to explain their acceptance / rejection of climate change. Using a textual content analysis, this study finds that media choice, motivated reasoning, conspiracy ideation, and the scientific construction of knowledge all play important roles in explanations for climate science rejection. Work and educational background, as well as a reframing of the scientific consensus as a "religion," add new analytical perspectives to the motivated reasoning explanations offered in prior research. This analysis also finds that the explanations for climate science denial given by respondents are often complex, falling into two or more of the explanation types suggesting that science rejection may be a more complex social process than previously thought.

Planned grazing management in rangelands may improve carbon sequestration potential of soils by increasing plant biomass and the rate of nutrient cycling, which might mitigate global warming. The effects of high-intensity, short-duration planned grazing of sheep on several soil and ecosystem properties were investigated on a mixed grassland in San Luis Obispo, CA. The objectives of this study were to (a) identify soil properties related to soil C sequestration in rangelands; (b) determine if planned grazing improved soil carbon sequestration; (c) quantify changes in identified variables in grazed and rested plots; and (d) analyze any changes in plant species composition attributable to grazing. Total rest exclosures and short-duration grazing by sheep at average stocking densities of 115,000 pounds per acre were applied at two sites with clay-loam soils: a rangeland site that had been rested for over 50 years (REX), and an adjacent site that was previously rested for over 50 years, and subsequently grazed for six years (GR). Bare soil, live plants, plant litter, and perennial and annual plant densities were not different between sites. Soil organic carbon (SOC) was higher at the GR site, but total nitrogen was not different between sites, resulting in higher C:N ratios at the GR site. Soil pH was lower at the GR site, moisture was higher at the GR site, and bulk density and aggregate stability were not different between sites. There was a higher incidence of black soils at the REX site, suggesting perhaps a difference in soil mineralogy which may impact SOC. Treatment did not have an effect on any of the variables investigated except perennial plant diversity, in which grazed plots had lower species diversity than rested plots. Site aspect may have an effect on the results, as the GR site was northwest-facing while the REX site was south-facing. It is possible that higher SOC at the GR site is due to topography, rather than grazing management. Further investigation is required, but if grazing can be used in California as a strategy for increasing soil carbon sequestration, the rates of desertification may be slowed and damage caused to the ecosystem by global warming may be reduced.

With a warming climate and the usage of monocultures in food production it is possible we may face more issues concerning food insecurity in the future as pollinators struggle to find food in agricultural landscapes. Therefore, it is of value to know whether common agricultural weeds are important sources of food for pollinators. Pollinators are vital in the growing of food-crops and may depend on different agricultural weeds during their flying season. This study is based on observational citizen science data on the flowering of 24 agricultural weeds classified as useful to pollinators in the years 2008-2022. Data on first flowering and length of flowering was compared between life history classifications based on life span and time of germination. The results showed that while there is variation both between groups and within groups among the selected species, summer annuals are among the last to start flowering. Species classed as “summer and winter annuals”, i.e that can germinate either in spring or autumn, had a longer flowering period than the other classes. Winter annuals were first to flower while the perennials and “summer and winter annuals” differed more among each other. Weather dependency was also addressed by comparison over years. Overall, the selected species were not significantly affected by mean winter temperature, mean summer temperature or mean summer precipitation.

As a temperature-delineated boundary, Arctic treeline is predicted to shift poleward and tree growth is expected to increase in response to rapid warming. The massive scale of the Arctic treeline magnifies these changes to impact energy balance, carbon balance, and climate-related feedbacks at local, regional, and global scales. Yet, not all sections of the Arctic treeline are reporting growth, suggesting factors other than temperature may be becoming more limiting as the climate continues to change. This dissertation investigates how water availability and tree size may modify the response to climate change of a dominant conifer species (white spruce, Picea glauca) growing at an Arctic treeline site in the Brooks Range, Alaska, USA. The first chapter examines the influence of temperature and water availability on population regeneration and individual tree growth during the 20th century. A climatic shift towards a warmer and drier climate after 1975 caused divergent responses of sapling regeneration and mature tree growth, suggesting that, while individuals have grown, this section of treeline has remained relatively stationary. The second chapter explores the present-day relationships between tree size, temperature, moisture availability, and tree growth by examining the response of intra-annual radial stem growth rate to changing environmental conditions at the Arctic treeline. Tree size and water availability play important roles in moderating the growth response to increasing temperature. Finally, in the third chapter, the environmental cues which trigger the onset of radial stem growth in spring are identified. The results suggest a combination of winter chilling and subsequent spring heat accumulation initiates onset, like trees growing at lower latitudes. However, the chilling and heating thresholds at this Arctic treeline site were far colder than those identified at lower latitudes, suggesting local adaptation to harsh Arctic winters and springs. Through these new findings, this dissertation advances our understanding of Arctic treeline dynamics and will help to predict the future of the Arctic treeline more accurately in a rapidly changing climate.

The importance of Hydrogen (H2) in current global energy systems is undeniable. Moving from the energy systems depending on fossil fuel to energy systems that are carbon-free is a necessity, thus solutions such as hydrogen economy is required. Especially after recent geopolitical challenges in Europe which could make the energy acquisition a crucial problem. Liquid organic hydrogen carriers (LOHC) are applicable pathways for transitioning H2 into energy and to avoid the storage and transportation limitations of gaseous and liquid H2. Formic acid (FA) is an attractive alternative for such purposes due to its minimal level of toxicity and its significant volumetric storage capacity for H2. In this study, a Life cycle assessment (LCA) of the supply chain involving the Trans-Atlantic export of energy from Canada to Germany is conducted using formic acid as a LOHC and OxFA process to convert biomass to formic acid. The environmental impacts of all units and processes involved in this supply chain are examined, and the results are compared against other traditional systems for hydrogen production. A sensitivity analysis was also performed to recognize the crucial contributors and assess the processes and units that impose considerable influence on the overall environmental impact. / Thesis / Master of Applied Science (MASc) / Hydrogen (H2) plays a crucial role in transitioning from fossil fuel-based to carbon-free energy systems, a shift highlighted by recent geopolitical challenges in Europe. Liquid organic hydrogen carriers (LOHC) offer a solution for hydrogen storage and transport issues associated with its gaseous and liquid states. Formic acid (FA) is particularly promising as a LOHC due to its low toxicity and high hydrogen storage capacity. This study conducts a Life Cycle Assessment (LCA) of a supply chain that uses formic acid to export energy from Canada to Germany, involving the OxFA process for converting biomass to formic acid. The environmental impacts of all processes in this supply chain are evaluated and compared with traditional hydrogen production methods. Additionally, a sensitivity analysis identifies key contributors and assesses their impact on the overall environmental footprint.

Polar amplification (PA), defined as the enhanced warming of the polar region relative to the global average, is a robust feature of historical observations and simulations of future climate. Because PA has yet to be realized in the Antarctic, I mainly focus on Arctic amplification (AA). Despite the far-reaching consequences of Arctic warming and sea ice loss, the causes of AA and their relative importance remain contested. This dissertation highlights some of the most important AA-producing mechanisms by analyzing the different timescales over which AA develops following an increase in CO₂ in climate model simulations. First, an Arctic and global average energy budget analysis is derived for a collection of Coupled Model Intercomparison Project version 5 (CMIP5) models subjected to an instantaneous quadrupling of CO₂ (4xCO₂). I quantify the relative contributions of various AA mechanisms using radiative kernels for 150 years after 4xCO₂ and compare mechanisms important at the beginning of the simulations against those when the models are in a quasi-equilibrium state. To focus on the fast timescales of AA, a new ensemble of Community Earth System Model (CESM) simulations was generated to observe the development of AA on ultrafast timescales (< 1 month) and to investigate the impact of the season in which CO₂ is increased. Finally, AA mechanisms and their seasonality are compared to those acting to produce Antarctic amplification (AnA). Motivated by this analysis, a new Python package called ClimKern was developed to simplify feedback calculations using radiative kernels and intercompare results based on different kernels. This work shows that AA occurs on incredibly fast timescales following CO₂ forcing, developing within three months in CMIP5 models and on the order of days in the CESM simulations in which CO₂ increases in January. The feedbacks important for AA immediately following CO₂ increase are not the same as those important decades afterward, demonstrating a strong time dependence of AA mechanism strength. Although sea ice loss and the associated surface albedo feedback play leading roles in the long-term development of AA, other mechanisms more clearly explain the rapid development of AA, namely, temperature feedbacks and the surface latent heat flux response. AnA also develops on ultrafast timescales, though on timescales greater than one month, AA is considerably greater than AnA. This results from a stronger SHU response and temperature feedbacks in the Arctic compared to the Antarctic. Lastly, I find that the magnitudes of feedbacks, especially the surface albedo feedback, exhibit considerable sensitivity to the kernel choice, indicating that using several different sets of kernels will make future feedback studies more robust.

IPCC, WHO and FAO have recently published reports connecting the animal industry with Global warming, cancer and 70% of modern diseases. In fact, IPCC (2014) indicated that the greatest potential for reducing emissions is placed on the consumer’s level. For this context, grounded in concepts of the Foucauldian Discourse Analysis and the Compositional Analysis (Rose, 2001) this study analyzed a series of advertisements issued in the period after the reports (2013-2015). The analysis was guided by three central questions: (1) Which linguistic and visual approaches, as well as their organization and strategies applied in the discourse, is the Animal Industry using in the construction of their advertisements and how they react to this moment of crises? (2) Considering Barthes ́ approach of food as symbols containing a communicational construction, what are the meanings built around animal products understood from the perspective of discourse? (3) How is the Animal Industry positioning themselves towards audiences and culture and what functions are they giving to themselves in society? Following a political theoretical framework, the proposition that the animal commodification is an ideology affirmed in western societies will be discussed. Advertisements from seven enterprises of the Animal Industry in EU will be used, selected for having leading positions in their sectors (meat and dairy). Among the results, it was verified that the relation toward human interaction is the major enunciator in the advertisements. The following lines of enunciation were identified: example and empathy; imperative discourses; tradition. The enunciations of meat have emotional basis; while the constructions around dairy focuses on the western representation of archaic nature (Haraway, 1989). The denotative qualities of the foods where very little considered. The political and ethical questions around the animal products were absent. This study focuses on the necessity of a political and critical approach of the marketing strategies of the Animal Industry. KEY WORDS: Animal Industry, Global Warming, Discourse Analysis, Foucault