京都大学 / 新制・課程博士 / 博士(農学) / 甲第24681号 / 農博第2564号 / 新制||農||1100(附属図書館) / 学位論文||R5||N5462(農学部図書室) / 京都大学大学院農学研究科生物資源経済学専攻 / (主査)教授 栗山 浩一, 教授 浅見 淳之, 教授 伊藤 順一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

学位プログラム名: 京都大学大学院思修館 / 京都大学 / 新制・課程博士 / 博士(総合学術) / 甲第25517号 / 総総博第39号 / 新制||総総||7(附属図書館) / 京都大学大学院総合生存学館総合生存学専攻 / (主査)准教授 趙 亮, 教授 長山 浩章, 教授 関山 健 / 学位規則第4条第1項該当 / Doctor of Philosophy / Kyoto University / DGAM

Thesis advisor: Pablo Guerron-Quintana / This thesis consists of two self-contained essays on topics in applied macroeconomics. In the first chapter, I study how heterogeneous sensitivities to weather fluctuations and interregional production networks impact the measurement of weather shocks’ impact on economic activity in the United States. I start the analysis by building a general equilibrium model where the impact of weather fluctuations on productivity is state-sector dependent, and networks expose sectors to weather shocks from other regions through the use of intermediate inputs. Then, I quantify the relevance of these mechanisms, combining the model’s predictions with annual data on sectoral GDP and average temperatures by state from 1970 to 2019. My estimates show that models that do not consider these characteristics underestimate the aggregateimpact of weather fluctuations by at least a factor of 3. In particular, when the whole economy faces an unexpected increase in temperature of 1 Celsius degree, the contraction in economic activity increases from -0.13 to -0.37 percent once heterogeneity is considered and -1.14 percent when networks are included. In the second chapter, I propose a new methodology to disentangle between terms of trade movements caused by global shocks and those resulting from country-specific terms-of-trade fluctuations. This methodology extends the so-called maximum-share approach in two ways. Firstly, a global shock is identified as the shock with the highest explanatory power on the forecast error variance of a set of exogenous variables. This is in contrast to the typical approach of using only one variable as a source of information to identify a shock. Secondly, country-specific terms-of-trade shocks are identified as shocks that satisfy two conditions: (i) maximum explanation power on terms-of-trade variability and (ii) orthogonality to global shocks, allowing me to isolate the main drivers of terms of trade that are not related to global fluctuations. I apply this methodology to data on ten small open economies(SOEs) and show that global shocks contribute - on average- to 33 percent of their business cycle fluctuations. The contribution of global shocks to terms-of-trade variability is close to 20 percent, meaning that around 80 percent of terms-of-trade movements have country-specific origins. Interestingly, on average, country-specific terms-of-trade shocks are responsible for less than 10 percent of SOE business cycle variability. These results help to reconcile current estimates on the importance of terms of trade and suggest an intensive evaluation of the origins of terms-of-trade movements by policymakers before any intervention. / Thesis (PhD) — Boston College, 2024. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

Human behaviour produces massive greenhouse gas emissions, which trigger climate change and more unpredictable weather conditions. The fluctuation of daily weather corresponds to variations of everyday travel behaviour. This influence, although is less noticeable, can have a strong impact on the transport system. Specifically, the climate in Sweden is becoming warmer in the recent 10 years. However, it is largely unknown to what extent the change of travel behaviour would respond to the changing weather. Understanding these issues would help analysts and policy makers incorporate local weather and climate within our policy design and infrastructure management. The thesis contains eight papers exploring the weather and climate impacts on individual travel behaviour, each addressing a subset of this topic. Paper I explores the weather impact on individual’s mode choice decisions. In paper II and III, individual’s daily activity time, number of trips/trip chains, travel time and mode shares are jointly modelled. The results highlight the importance of modelling activity-travel variables for different trip purposes respectively. Paper IV develops a namely nested multivariate Tobit model to model activity time allocation trade-offs. In paper V, the roles of weather on trip chaining complexity is explored. A thermal index is introduced to better approximate the effects of the thermal environment. In paper VI, the role of subjective weather perception is investigated. Results confirm that individuals with different socio-demographics would have different subjective weather perception even given similar weather conditions. Paper VII derives the marginal effects of weather variables on transport CO2 emissions. The findings show more CO2 emissions due to the warmer climate in the future. Paper VIII summaries the existing findings in relations between weather variability and travel behaviour, and critically assesses the methodological issues in previous studies. / <p>QC 20160516</p> / Understanding the complexity of changes of travelers’ activity-travel choices and related transport CO2 emissions due to the variation of weather and climate in Sweden (Centre för Transport Studie, projekt kod: 446) / Understanding the impacts of weather and climate change on travel behavior (Centre för Transport Studie, projekt kod: 291)

Populations often experience environmental conditions that are variable both in space and in time. Understanding the demographic and evolutionary dynamics of populations in such variable environments has very practical implications for conservation biology, pest and pathogen control, management of antibiotic resistance. This thesis is an attempt to study the ecological and evolutionary implications of spatial and temporal variations of the environment.First, I study how spatially heterogeneous and temporally changing conditions influence the demographic dynamics of a genetically uniform population. The growth of the population is enhanced when individuals preferentially accumulate in high quality habitats. Migration between locations facilitates a good arrangement of individuals such that in general, an intermediate rate of migration maximizes the growth rate.Second, I develop a model where the growth rate of individuals depends on the environment but also on their genetic quality, and possibly on the interaction between the environment and the genotype. If the performance of different genotypes tradeoffs across the environments, several genotypes may be maintained locally in the environment that suit them and a pattern of local adaptation emerges. Moreover, I show that adaptation of populations to environmental fluctuations in the environment generates very dynamic changes in the genetic composition that lag behind the environmental change. Adaptation may be facilitated by the influx of migrants coming from other demes.How can we detect such patterns of adaptation in wild or experimental populations? I develop a formal analysis of several experimental and statistical techniques that are used to detect patterns of local and temporal adaptation. I provide recommendations regarding efficient experimental designs and statistical techniques to detect local adaptation. I also develop a new framework for the analysis of patterns of adaptation in time. I illustrate the potential use of this approach using a data set measuring the adaptation of HIV to the immune response of several recently infected patients. / Populations often experience environmental conditions that are variable both in space and in time. Understanding the demographic and evolutionary dynamics of populations in such variable environments has very practical implications for conservation biology, pest and pathogen control, management of antibiotic resistance. This thesis is an attempt to study the ecological and evolutionary implications of spatial and temporal variations of the environment.First, I study how spatially heterogeneous and temporally changing conditions influence the demographic dynamics of a genetically uniform population. The growth of the population is enhanced when individuals preferentially accumulate in high quality habitats. Migration between locations facilitates a good arrangement of individuals such that in general, an intermediate rate of migration maximizes the growth rate.Second, I develop a model where the growth rate of individuals depends on the environment but also on their genetic quality, and possibly on the interaction between the environment and the genotype. If the performance of different genotypes tradeoffs across the environments, several genotypes may be maintained locally in the environment that suit them and a pattern of local adaptation emerges. Moreover, I show that adaptation of populations to environmental fluctuations in the environment generates very dynamic changes in the genetic composition that lag behind the environmental change. Adaptation may be facilitated by the influx of migrants coming from other demes.How can we detect such patterns of adaptation in wild or experimental populations? I develop a formal analysis of several experimental and statistical techniques that are used to detect patterns of local and temporal adaptation. I provide recommendations regarding efficient experimental designs and statistical techniques to detect local adaptation. I also develop a new framework for the analysis of patterns of adaptation in time. I illustrate the potential use of this approach using a data set measuring the adaptation of HIV to the immune response of several recently infected patients.

As populações de insetos e os serviços ecossistêmicos realizados por esses organismos estão ameaçados por ações antrópicas, devido à conversão de habitats naturais em paisagens agriculturáveis extensa e/ou urbanizadas. Essas modificações geradas nas paisagens naturais criaram novos cenários e aumentou os desafios de investigar como o arranjo espacial do uso do solo pode afetar os processos ecológicos. Apesar do aumento do número de estudos com esse foco, ainda são escassas as avaliações na região tropical que analisam os efeitos das mudanças da paisagem sobre os polinizadores e a seus serviços. Assim, a fim de prover mais dados que possam contribuir para o entendimento das questões acima, este estudo foi estruturado em três capítulos com os seguintes objetivos: (1) investigar o papel das abelhas na produção de sementes e qualidade do óleo do girassol; (2) avaliar os efeitos de diferentes proporções da heterogeneidade espacial e de cobertura florestal na comunidade de insetos que visitam o girassol, e; (3) avaliar a provisão do serviço de polinização nessa cultura. Para isso, o primeiro capítulo foi realizado na Escola Superior de Agricultura \"Luiz de Queiroz\" - ESALQ/USP, Piracicaba, e os experimentos dos capítulos subsequentes foram conduzidos em 12 paisagens com gradiente de heterogeneidade espacial e cobertura florestal de Mata Atlântica, no Corredor Cantareira-Mantiqueira, Estado de São Paulo, Brasil. Este estudo mostrou a visitação de abelhas em girassóis híbridos aumentou o peso dos aquênios em 91%, os níveis de vitamina E em 45% e os ácidos graxos insaturados em 0,3%, quando comparados a flores isoladas desses polinizadores. Além disso, estimou-se que, devido aos serviços de polinização fornecidos pelas abelhas, o produtor praticamente duplica o valor de venda dos aquênios por hectare de área cultivada. Em relação aos experimentos conduzidos nas 12 paisagens da Mata Atlântica, foram amostrados 2.181 indivíduos de 130 espécies de insetos, pertencentes a 40 famílias de seis ordens. As abelhas foram os visitantes florais mais abundantes (77,2%) e com maior riqueza (36,9%) dentre os visitantes florais. Apis mellifera dominou a comunidade de insetos visitantes, seguida por Trigona spinipes. Essas espécies são consideradas \"super-generalistas\" quanto às suas preferências florais e importantes polinizadores em áreas degradadas, já que suas populações se mantêm em paisagens mais simplificadas e desfavoráveis a outros polinizadores. Isso pode explicar a relação negativa entre a proporção de floresta e a riqueza de insetos que visitaram os girassóis. A heterogeneidade espacial não teve efeito significativo nos índices de diversidade. No entanto, é necessário cuidado ao interpretar esses dados e levar em consideração a qualidade dos habitats naturais da paisagem circundantes aos girassóis e os traços comportamentais e ecológicos de cada espécie amostrada. Neste estudo, ficou evidente que, apesar de A. mellifera contribuir para o incremento da produtividade do girassol, o serviço de polinização realizado por outros insetos foi mais eficiente e efetivo, uma vez que influenciou positivamente no aumento do número e peso dos aquênios por capítulo, na quantidade de óleo extraído das sementes e no nível de gama- tocoferol contido no óleo. Além disso, houve também a diminuição no teor de ácidos graxos saturados. Como seu consumo aumenta a concentração de colesterol no sangue humano, a melhora da composição nutricional do óleo de girassol foi auxiliada pela ação de polinizadores. Assim, este estudo destacou o importante papel dos polinizadores para a segurança alimentar humana e a relação entre características da paisagem e o serviço de polinização, fornecendo dados básicos úteis para estratégias políticas que podem auxiliar na proteção dos polinizadores. / Insect populations and ecosystem services performed by these organisms are threatened by anthropogenic actions, such as the conversion of natural habitats into extensive agricultural and/or urbanized areas. These changes in natural landscapes have created new scenarios and increased the challenges of investigating the effect of spatial arrangement of land use in ecological processes. Despite the increasing number of studies focusing on this topic, evaluations in tropical region that analyze the effects of landscape changes on pollinators and their provision of pollination services are still scarce. Thus, in order to provide more data that address the aforementioned issues, this study was structured into three chapters, with the following aims: (1) to investigate the role of bees in seed production and sunflower oil quality; (2) to evaluate the effects of spatial heterogeneity and forest cover on sunflower-visiting insect community, and; (3) to evaluate the provision of pollination service in sunflowers. To achieve these goals, the experiments were carried out at the \"Luiz de Queiroz\" College of Agriculture - ESALQ/USP, Piracicaba, and in 12 landscapes across gradients of spatial heterogeneity and Atlantic Rainforest cover, in the Cantareira-Mantiqueira Corridor region, São Paulo State, Brazil. This study showed that bee visitation in hybrid sunflowers increased the achenes weight by 91%, the levels of vitamin E by 45% and unsaturated fatty acids by 0.3%. Furthermore, it was estimated that due to the pollination services provided by the bees, the grower of the sunflower hybrid used in this study doubles the sales value of achenes per hectare of cultivated area. In relation to the experiments conducted in the 12 Atlantic Rainforest landscapes, 2,181 individuals belonging to 130 insect species of 40 families (six orders) were sampled. Bees were the most abundant (77.2%) and the richest (36.9%) sunflower visitors. Apis mellifera dominated sunflower-visitor communities, followed by Trigona spinipes. These species are traditionally considered \"super generalists\" in relation to their floral preferences and important pollinators in degraded areas, since their populations remain in simplified landscapes that are unsuitable to other pollinators. It could explain the negative relationship between the forest proportion and the richness of sunflower-visiting insect community. Spatial heterogeneity had no significant effect on the diversity indexes. However, it is necessary to interpret these data with caution and to take in account the quality of the natural habitats surrounding the sunflowers and the behavioral and ecological traits of each insect species. Although A. mellifera contributed to increase sunflower productivity, the pollination services performed by other insect taxa were more efficient and effective, as they contributed to increase the number and weight of achenes per sunflower head, the quantity of oil extracted from seeds and the gamma-tocopherol oil concentration. In addition, there was a decrease in levels of saturated fatty acids. Since their consumption increases the concentration of cholesterol in human blood, the pollinators had an important role in the improvement of the nutritional composition of sunflower oil. Thus, this study highlighted the important role of pollinators for human food security and the relationship between surrounding landscapes and pollination service, providing useful baseline figures to policy strategies that can help to safeguard pollinators.

Disturbances are ubiquitous features of most northern forest ecosystems. The subsequent response of plant assemblages on both short (resistance or not) and long term (recolonization or not) will depend on a number of factors operating at several spatial scales. In boreal forest ecosystems, bryophyte assemblages are a conspicuous and species rich group of plants for which these processes are poorly understood. Using a combination of experimental and observational approaches this thesis explores these questions for closed-canopy bryophyte assemblages in relation to a) microtopography (both for the initial and long-term response), b) environmental constrains during post-logging succession and c) disturbance type. My results clearly show that the shade and shelter provided by microtopographic surface structures can increase survival rates of bryophytes following clear-cut logging by decreasing mortality from microclimatic stress and mechanical disturbance. Following clear-cutting, the recovery of forest floor and dead wood living bryophytes seems to be a relatively steady and progressive process without any major bottleneck episodes in the young or semi-mature forest stages with much of the pre-disturbance composition recovered after 50 years. Although boulders were found to increase the initial survival on clear-cuts and hence increase disturbance resistance, we found no evidence that boulders influenced the subsequent recolonization process. Lastly, strong compositional dissimilarities were found in young forests (40 years) following clear-cut logging, wildfire and insect outbreak, indicating divergent trajectories to occur following different disturbances. Hence, early seral stages of forest ecosystems regenerating after natural disturbances seem to compliment young managed forests in maintaining landscape level diversity. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Manuscript. Paper 4: Manuscript.

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Cette thèse se propose de mettre en perspective l’impact de l’environnement entrepreneurial, afin d'expliquer les raisons de la variation spatiale du niveau de développement régional pour les régions de l’Union Européenne et celles des régions tunisiennes. Cette inégalité régionale s’accompagne par une non-stationnarité spatiale des relations modalisées dans l’espace, ce qui implique que certaines variables peuvent avoir un effet positif dans quelques régions, alors que des effets négatifs sont observables dans d’autres régions. Pour aborder la question des inégalités régionales liées à une contribution entrepreneuriale dans un contexte spatiale, trois chapitres, sous forme d’articles, ont été développés. Le premier chapitre étudie l’hétérogénéité spatiale de l’impact de l’environnement entrepreneurial sur le développement des régions de l’Union Européenne. Le deuxième s’intéresse à la description des répartitions spatiales globales et locales de l’indice de développement régional en Tunisie, ainsi qu'à l’impact de la variation de l’effet de la micro-entreprise sur l’indice de développement des régions (délégations) tunisiennes. Le dernier chapitre explique les facteurs favorisant un environnement entrepreneurial adéquat pour attirer les micro-entreprises dans les régions (délégations) tunisiennes principalement défavorisées mais qui sont cependant dans une phase de développement.En se basant sur un échantillon composé de 246 régions de l’Union Européenne, les résultats du premier chapitre annoncent que l’environnement entrepreneurial contribue à expliquer les inégalités du développement entre les régions. Ce résultat révèle que promouvoir un entrepreneuriat d’opportunité face à un entrepreneuriat de nécessité dans les régions les moins développées de l’Union Européenne est une obligation, notamment dans les pays de l’Europe Centrale et Orientale. Le deuxième chapitre a pour objectif d’examiner l’effet de la micro-entreprise sur l’indice de développement des 262 régions tunisiennes à l’aide d’une analyse exploratoire des données Géo-référencées. Le résultat obtenu montre, sur la base d’un modèle spatial global, que la présence de la micro-entreprise dans une région impacte positivement le niveau de développement régional de celle-ci et de celles des régions voisines. A contrario, pour un modèle spatial local, nous constatons, d’une part que l'impact de la micro-entreprise s’affaiblit en se rapprochant des régions côtières (développées), et d’autre part que l'impact de la micro-entreprise est plus important dans les régions à faible niveau de développement par rapport à celles dotées d’un développement favorable. Les résultats du troisième chapitre affirment que l’entrepreneuriat par nécessité, un contexte social décourageant, la corruption, la faible fiabilité des structures d'appui et le déséquilibre entre la formation universitaire et l’offre d’emplois qualifiés sur le marché sont les facteurs majeurs freinant la survie de la micro-entreprise dans les régions en retard de développement. / This thesis proposes to put into perspective the impact of the entrepreneurial environment, in order to explain the reasons for the spatial variation of the level of regional development for the regions of the European Union and those of the Tunisian regions. This regional inequality is accompanied by non-stationary spatial modalized relationships in space, implying that certain variables can have a positive effect in some regions, while negative effects are observable in other regions. To address the issue of regional inequalities in an entrepreneurial contribution in a context space, three chapters, in the form of articles, have been developed. The first chapter sheds light on the spatial heterogeneity of the impact of the environment on the development of the European Union Regions. The second focuses on the description of spatial distributions global and local index to regional development in Tunisia, as well as the impact of the change in the effect of the micro-enterprise on the index of development of the Tunisian regions (delegations).The last chapter explains the factors fostering an entrepreneurial environment to attract micro-enterprises in the (delegations) Tunisian regions primarily disadvantaged but are in a phase of development .Based on a sample composed of 246 regions of the European Union, the results of the first chapter announced that the entrepreneurial environment helps explain inequalities in development between the regions. This result reveals that promote entrepreneurship of opportunity in the face of the necessity entrepreneurship in the regions the least developed in the European Union is an obligation, particularly in countries of Central Europe and Eastern. The second chapter is aimed to consider the effect of the micro-enterprise on the development index of 262 Tunisian regions using an exploratory analysis of Geo-referenced data. The result shows, on the basis of a global spatial model, that the presence of the micro-enterprise or business in a region impacted positively the level of regional development and those of the neighboring regions. Conversely, for a local spatial model, we see, on the one hand that the impact of micro-enterprise weakens while approaching coastal areas (developed), and on the other hand the impact of the micro-enterprise is more important in the regions with low level of development compared to those with a favorable development. The results of the third chapter claim that entrepreneurship by necessity, a discouraging social context, corruption, low reliability of support structures and the imbalance between the academic training and supply of skilled jobs on the market are the major factors slowing down the survival of the micro-enterprise in under developed regions.

Uma metapopulação pode ser definida como uma população regional de populações locais geograficamente distintas, interconectadas por migração. Dentro deste contexto, modelos de dinâmica metapopulacional espacialmente implícitos descrevem a taxa de variação da proporção de manchas ocupadas por uma ou mais espécies por meio de um balanço entre os processos de colonização de manchas vazias e extinção de manchas ocupadas. O modelo metapopulacional de Levins prevê que mesmo na presença de habitat adequado, uma espécie pode se extinguir regionalmente, de forma determinística, se a intensidade de extinção for maior do que a intensidade de colonização. Além disso, este modelo sugere a existência de uma quantidade limiar de habitat remanescente, abaixo do qual a extinção regional determinística da espécie ocorre. Características importantes da dinâmica espacial, tais quais, efeito Allee, efeito resgate, colonização externa, qualidade da matriz, efeito anti-resgate e heterogeneidade de manchas podem ser incluídas em variantes do modelo de Levins. Uma outra extensão natural desses modelos é o agrupamento das manchas com relação ao seu estado de ocupação em modelos de metapopulações de espécies interativas, dando origem aos modelos de metacomunidades. Estudos de dinâmica de metacomunidades permitem a análise das relações entre a diversidade de espécies e a heterogeneidade ambiental no nível da paisagem, bem como as implicações de interações diretas e indiretas para a estrutura de comunidades.