Dissertations / Theses on the topic 'Spatial adjustment'

Doctor of Philosophy<br>Department of Geography<br>Douglas G. Goodin<br>Jesse A. Poland<br>Kevin Price<br>Wheat breeders are in a race for genetic gain to secure the future nutritional needs of a growing population. Multiple barriers exist in the acceleration of crop improvement. Emerging technologies are reducing these obstacles. Advances in genotyping technologies have significantly decreased the cost of characterizing the genetic make-up of candidate breeding lines. However, this is just part of the equation. Field-based phenotyping informs a breeder’s decision as to which lines move forward in the breeding cycle. This has long been the most expensive and time-consuming, though most critical, aspect of breeding. The grand challenge remains in connecting genetic variants to observed phenotypes followed by predicting phenotypes based on the genetic composition of lines or cultivars. In this context, the current study was undertaken to investigate the utility of UAS in assessment field trials in wheat breeding programs. The major objective was to integrate remotely sensed data with geospatial analysis for high throughput phenotyping of large wheat breeding nurseries. The initial step was to develop and validate a semi-automated high-throughput phenotyping pipeline using a low-cost UAS and NIR camera, image processing, and radiometric calibration to build orthomosaic imagery and 3D models. The relationship between plot-level data (vegetation indices and height) extracted from UAS imagery and manual measurements were examined and found to have a high correlation. Data derived from UAS imagery performed as well as manual measurements while exponentially increasing the amount of data available. The high-resolution, high-temporal HTP data extracted from this pipeline offered the opportunity to develop a within season grain yield prediction model. Due to the variety in genotypes and environmental conditions, breeding trials are inherently spatial in nature and vary non-randomly across the field. This makes geographically weighted regression models a good choice as a geospatial prediction model. Finally, with the addition of georeferenced and spatial data integral in HTP and imagery, we were able to reduce the environmental effect from the data and increase the accuracy of UAS plot-level data. The models developed through this research, when combined with genotyping technologies, increase the volume, accuracy, and reliability of phenotypic data to better inform breeder selections. This increased accuracy with evaluating and predicting grain yield will help breeders to rapidly identify and advance the most promising candidate wheat varieties.

Thesis (Ph.D)--Psychology, Georgia Institute of Technology, 2010.<br>Committee Chair: Walker, Bruce N.; Committee Member: Corballis, Paul M.; Committee Member: Corso, Gregory M.; Committee Member: Folds, Dennis J.; Committee Member: Houtsma, Adrianus J. M. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Unmanned aerial vehicles (UAV) have become an interesting and active research topic for photogrammetry. Current research is based on images acquired by an UAV, which have a high ground resolution and good spectral and radiometrical resolution, due to the low flight altitudes combined with a high resolution camera. UAV image flights are also cost effective and have become attractive for many applications including, change detection in small scale areas. One of the main problems preventing full automation of data processing of UAV imagery is the degradation effect of blur caused by camera movement during image acquisition. This can be caused by the normal flight movement of the UAV as well as strong winds, turbulence or sudden operator inputs. This blur disturbs the visual analysis and interpretation of the data, causes errors and can degrade the accuracy in automatic photogrammetric processing algorithms. The detection and removal of these images is currently achieved manually, which is both time consuming and prone to error, particularly for large image-sets. To increase the quality of data processing an automated process is necessary, which must be both reliable and quick. This thesis proves the negative affect that blurred images have on photogrammetric processing. It shows that small amounts of blur do have serious impacts on target detection and that it slows down processing speed due to the requirement of human intervention. Larger blur can make an image completely unusable and needs to be excluded from processing. To exclude images out of large image datasets an algorithm was developed. The newly developed method makes it possible to detect blur caused by linear camera displacement. The method is based on human detection of blur. Humans detect blurred images best by comparing it to other images in order to establish whether an image is blurred or not. The developed algorithm simulates this procedure by creating an image for comparison using image processing. Creating internally a comparable image makes the method independent of additional images. However, the calculated blur value named SIEDS (saturation image edge difference standard-deviation) on its own does not provide an absolute number to judge if an image is blurred or not. To achieve a reliable judgement of image sharpness the SIEDS value has to be compared to other SIEDS values of the same dataset. This algorithm enables the exclusion of blurred images and subsequently allows photogrammetric processing without them. However, it is also possible to use deblurring techniques to restor blurred images. Deblurring of images is a widely researched topic and often based on the Wiener or Richardson-Lucy deconvolution, which require precise knowledge of both the blur path and extent. Even with knowledge about the blur kernel, the correction causes errors such as ringing, and the deblurred image appears muddy and not completely sharp. In the study reported in this paper, overlapping images are used to support the deblurring process. An algorithm based on the Fourier transformation is presented. This works well in flat areas, but the need for geometrically correct sharp images for deblurring may limit the application. Another method to enhance the image is the unsharp mask method, which improves images significantly and makes photogrammetric processing more successful. However, deblurring of images needs to focus on geometric correct deblurring to assure geometric correct measurements. Furthermore, a novel edge shifting approach was developed which aims to do geometrically correct deblurring. The idea of edge shifting appears to be promising but requires more advanced programming.

Orientador: Ricardo Carlos Cordeiro<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas<br>Made available in DSpace on 2018-08-18T15:08:16Z (GMT). No. of bitstreams: 1 Mafra_AnaCarolinaCintraNunes_D.pdf: 19877794 bytes, checksum: a74a4b2bf9bccffacddd691b458d1fd3 (MD5) Previous issue date: 2011<br>Resumo: A busca em compreender determinados fenômenos epidemiológicos muitas vezes envolve uma ferramenta denominada análise espacial do risco. O estudo do espaço em que ocorrem determinados desfechos permite ao pesquisador considerar informações não coletadas através de questionários ou prontuários médicos. Também insere questões sobre o que faz com que determinada área dentro da região de estudo se associe com maior risco ou proteção para o desfecho estudado. Existem muitos métodos para obter análises espaciais do risco, como os modelos aditivos generalizados, que permitem incluir nestas análises outras informações de interesse dos indivíduos estudados. Porém, atualmente, os estudos epidemiológicos que consideram a distribuição espacial do risco são analisados apenas com desfechos dicotômicos como, por exemplo, quando se classifica o indivíduo em doente ou não-doente. Esta é uma limitação que este trabalho visa superar ao apresentar um processo analítico da distribuição espacial do risco quando se tem uma variável resposta multinomial. Além de apresentar esta nova ferramenta, este trabalho analisou dois desfechos epidemiológicos: o primeiro é proveniente de um estudo caso-controle sobre acidentes de trabalhado na cidade de Piracicaba em que a resposta foi: casos graves, casos leves ou controles; outra ilustração provém de um estudo transversal sobre criadouros de mosquitos no Distrito Sul de Campinas, onde se encontrou muitos criadouros, poucos criadouros ou nenhum criadouro. Primeiramente, faz-se necessária uma discussão sobre a adequação de cada modelo multinomial a alguns estudos epidemiológicos. Também se discute a escolha de um entre diversos modelos multinomiais e apresenta-se a maneira de interpretar os resultados da análise. Para tornar este método acessível a outros pesquisadores, são apresentadas funções computacionais para o processo analítico<br>Abstract: The search for understanding some epidemiological phenomena often involves an tool called spatial analysis of risk. The study of space in which certain outcomes occur allows the researcher to consider information that can not be collected through questionnaires or medical records. It also puts questions about what makes a certain area within the study region was associated with greater risk or protection for the outcome studied. Many techniques are used for this kind of study as the generalized additive models that fit the spatial analysis of the risk with others informations of interest. But now, epidemiological studies that consider the spatial distribution of risk are analyzed only with dichotomous outcomes, such as when it classifies the individual in case or control. This is a limitation that this study aims to overcome when presenting an analytical process of the spatial distribution of risk when you have a multinomial response variable. In addition to presenting this new tool, this study analyzed two outcomes: first, from a case-control study of precarious workers in the city of Piracicaba in which the response was: severe cases, mild cases or controls. Another illustration comes from a cross-sectional study on mosquito breeding sites in the Southern District of Campinas, where we met many breeding sites, few or no breeding sites. First, it is necessary a discussion on the appropriateness of each multinomial model to some epidemiological studies. It also discusses the choice of one among several multinomial models and shows the way to interpret the results of the analysis. We present the computational functions for the analytical process to make this method accessible to other researchers<br>Doutorado<br>Epidemiologia<br>Doutor em Saude Coletiva

L'investissement et l'innovation jouent un rôle important dans le secteur agricole, permettant aux exploitations de s'adapter aux changements de politiques et aux conditions du marché. Au cours des dernières décennies, les exploitations agricoles de l'Union européenne (UE) ont été confrontées à des changements substantiels à travers la politique agricole commune (PAC). C'est notamment le cas du secteur laitier, qui a vu la fin du régime de quotas laitiers et également vu une volatilité accrue des prix. De tels changements pourraient affecter la productivité et l’efficacité des exploitations agricoles, la compétitivité du secteur laitier et les changements structurels. Comprendre les mécanismes sous-jacents au comportement d’investissement des exploitations pourrait permettre d’identifier les principaux facteurs qui influent sur les tendances observées. Cela pourrait aider à anticiper les futurs changements structurels, prévoir les besoins des exploitations et aider les décideurs publicet les autres acteurs du secteur agricole à adapter leurs politiques. La thèse contribue à cet objectif en analysant pour les exploitations laitières d'une sous-région de Bretagne (Ille-et-Vilaine) en France, (i) l'impact de la suppression du quota laitier sur les décisions d'investissement des agriculteurs et l'hétérogénéité de leurs réactions (ii) le lien entre la performance agricole et les décisions d'investissement des agriculteurs, (iii) le rôle des interactions sociales liées aux effets de voisinage sur la décision d'investissement des agriculteurs. Les résultats montrent que la fin<br>: Investment and innovation play an important role in the agricultural sector, allowing farms to adapt to policy changes and market condition changes. In the last decades, farms in the European Union (EU) have faced substantial changes in the Common Agricultural Policy (CAP). This is particularly the case of the dairy sector, which has seen the end of milk quota regime and increased price volatility. Such changes could affect farm productivity and efficiency, the dairy sector’s competitiveness and structural change. Understanding the mechanisms underlying farms’ investment behaviour could allow identifying key drivers that influence the observed trends. This could help anticipate future structural changes, predict farms’ needs and help policy makers and other stakeholders in farming to adapt their policy. The thesis contributes to this objective by analysing for dairy farms in a sub-region of Brittany (Ille-et-Vilaine) in France, (i) the impact of the termination of the milk quota onfarmers’ investment decisions and the heterogeneity of farm investment behaviour, (ii) the link between farm performance and farmers’ investment decisions, (iii) the role of social interactions related to neighbourhood effects on farmers' investment decision. Findings show that the termination of the dairy quota policy increased farmers’ incentive to invest, contributing to the trend towards larger, more capital intensive and more specialised dairy farms. In addition, the thesis underlines the need to take into account farmers’ heterogeneity in modelling investment behaviour. Doing so allows

The extractive activity carried out by the mangaba collectors of the municipality of Barra dos Coqueiros has been historically marked by disputes and conflicts between these representatives of the local traditional communities and the owners of lands where these workers perform a considerable part of their activity. However, even this scenario unfavorable to the social and cultural reproduction of these communities, governed by the unequal relations established in the conflict between the use and the legal ownership of the land, never endangered the continuity of the patrimonial activity of the mangaba collectors nor its perspective of permanence in the rural area of the municipality. Since the first decade of the twentieth century, however, the process of production of the area governed by financial capital, which had the construction of the Aracaju - Barra dos Coqueiros Bridge in 2006, provoked a damaging intensification of real estate speculation in the municipality In accordance with the sociometabolic logic of capitalist accumulation which, in its spatial adjustments, has appropriated vast areas of its rural space by constructing a series of real estate projects, such as closed condominiums of houses, apartments and urbanized lots The creation of large open lots areas. This process of appropriation of space by the real estate market has largely reached the way of life and work of local traditional communities, which follow a logic of work and production that depends, moreover, on extractivism in areas of which they do not have legal ownership. Thus, these social subjects have been seriously precarious with the process of urban expansion that intensively reduces the areas available for extractivism of the restinga fruits, completely compromising their autonomy from the land, and with that, also their permanence in the agrarian space Of the municipality. In another facet of state action, the municipal administration of Barra dos Coqueiros has also promoted serious impediments to the survival and permanence of the mangaba collectors of the municipality, by defining the areas of the local villages as urban perimeters, thereby imposing the collection of High rates of IPTU, which can hardly be paid by these social subjects. Thus, in multideterminations, the capitalist State establishes the proposal of urban expansion as a model of development, against which these social subjects must articulate and organize themselves in their struggle, inscribed in the universality of the expansion of capital over the peasant territories, Struggle to remain on earth, condition of life, production and autonomy.<br>A atividade extrativista desempenhada pelas catadoras de mangaba do município de Barra dos Coqueiros tem sido historicamente marcada por disputas e conflituosidades entre essas representantes das comunidades tradicionais locais e os proprietários de terras onde essas trabalhadoras realizam parte considerável de sua atividade. Todavia, mesmo esse cenário desfavorável à reprodução social e cultural dessas comunidades, regido pelas relações desiguais estabelecidas no conflito entre o uso e a propriedade legal da terra, nunca chegou a por em risco a continuidade da atividade patrimonial das catadoras de mangaba e tampouco sua perspectiva de permanência no espaço rural do município. Entretanto, desde a primeira década do século XX, o processo de produção do espaço regido pelo capital financeiro e que teve como estopim a construção da Ponte Aracaju – Barra dos Coqueiros no ano de 2006 tem provocado uma danosa intensificação da especulação imobiliária no município, especializada de acordo com a lógica sociometabólica da acumulação capitalista que, em seus ajustes espaciais, vem se apropriando de vastas áreas do seu espaço rural a partir da construção de uma série de empreendimentos imobiliários, como condomínios fechados de casas, de apartamentos e de lotes urbanizados além da criação de extensas áreas de loteamentos abertos. Esse processo de apropriação do espaço pelo mercado imobiliário tem atingido amplamente o modo de vida e trabalho das comunidades tradicionais locais, que seguem uma lógica de trabalho e produção que depende, sobremodo, do extrativismo em áreas das quais não detêm a propriedade legal. Dessa forma, esses sujeitos sociais tem sido seriamente precarizados com o processo de expansão urbana que reduz intensamente as áreas disponíveis para o extrativismo dos frutos da restinga, comprometendo por completo sua autonomia a partir da terra, e com isso, também sua permanência no espaço agrário do município. Em outra faceta da ação do Estado, a própria administração municipal de Barra dos Coqueiros tem também promovido sérios empecilhos à sobrevivência e à permanência das catadoras de mangaba do município, ao definir as áreas dos povoados locais como perímetros urbanos, impondo com isso a cobrança de altas taxas de IPTU, as quais dificilmente poderão ser pagas por esses sujeitos sociais. Dessa forma, em multideterminações o Estado-capital estabelece a proposta da expansão urbana como modelo de desenvolvimento, frente à qual esses sujeitos sociais precisam articular-se e organizar-se em sua luta, inscrita na universalidade da expansão do capital sobre os territórios camponeses, luta para permanecer na terra, condição de vida, trabalho e autonomia.

This thesis draws on David Harvey’s concept of “accumulation by dispossession” and an international political economy (IPE) approach centred on the institutional arrangements and power structures that privilege certain actors and values, in order to critique current capitalist practices of primitive accumulation by the global corporate extractive industry. The thesis examines how accumulation by dispossession by the global extractive industry is facilitated by the “free entry” or “free mining” principle. It does so by focusing on Canada as a leader in the global extractive industry and the spread of this country’s mining laws to other countries – in other words, the transnationalisation of norms in the global extractive industry – so as to maintain a consistent and familiar operating environment for Canadian extractive companies. The transnationalisation of norms is further promoted by key international institutions such as the World Bank, which is also the world’s largest development lender and also plays a key role in shaping the regulations that govern natural resource extraction. The thesis briefly investigates some Canadian examples of resource extraction projects, in order to demonstrate the weaknesses of Canadian mining laws, particularly the lack of protection of landowners’ rights under the free entry system and the subsequent need for “free, prior and informed consent” (FPIC). The thesis also considers some of the challenges to the adoption and implementation of the right to FPIC. These challenges include embedded institutional structures like the free entry mining system, international political economy (IPE) as shaped by international institutions and powerful corporations, as well as concerns regarding ‘local’ power structures or the legitimacy of representatives of communities affected by extractive projects. The thesis concludes that in order for Canada to be truly recognized as a leader in the global extractive industry, it must establish legal norms domestically to ensure that Canadian mining companies and residents can be held accountable when there is evidence of environmental and/or human rights violations associated with the activities of Canadian mining companies abroad. The thesis also concludes that Canada needs to address underlying structural issues such as the free entry mining system and implement FPIC, in order to curb “accumulation by dispossession” by the extractive industry, both domestically and abroad.

This diploma thesis evaluates continuity of two different and stand-alone documents that fundamentally affect the character of the area. This continuity of spatial plan and comprehensive land adjustment is compared in the selected area of the cadastral territory of municipality Libějice. The object of my research were public works and public interest measurements in the spatial planning and the plan of common facilities in the comprehensive landscaping, where in the case of these two documents lead to consensus. The results are presented in both text and graphical form, processed by a geographic information system ArcGIS 10th.

<p>Unmanned aerial vehicles (UAVs) equipped with imaging systems and integrated global navigation satellite system/inertial navigation system (GNSS/INS) are used for a variety of applications. Disaster relief, infrastructure monitoring, precision agriculture, and ecological forestry growth monitoring are among some of the applications that utilize UAV imaging systems. For most applications, accurate 3D spatial information from the UAV imaging system is required. Deriving reliable 3D coordinates is conditioned on accurate geometric calibration. Geometric calibration entails both spatial and temporal calibration. Spatial calibration consists of obtaining accurate internal characteristics of the imaging sensor as well as estimating the mounting parameters between the imaging and the GNSS/INS units. Temporal calibration ensures that there is little to no time delay between the image timestamps and corresponding GNSS/INS position and orientation timestamps. Manual and automated spatial calibration have been successfully accomplished on a variety of platforms and sensors including UAVs equipped with frame and push-broom line cameras. However, manual and automated temporal calibration has not been demonstrated on both frame and line camera systems without the use of ground control points (GCPs). This research focuses on manual and automated spatial and temporal system calibration for UAVs equipped with GNSS/INS frame and line camera systems. For frame cameras, the research introduces two approaches (direct and indirect) to correct for time delay between GNSS/INS recorded event markers and actual time of image exposures. To ensure the best estimates of system parameters without the use of ground control points, an optimal flight configuration for system calibration while estimating time delay is rigorously derived. For line camera systems, this research presents the direct approach to estimate system calibration parameters including time delay during the bundle block adjustment. The optimal flight configuration is also rigorously derived for line camera systems and the bias impact analysis is concluded. This shows that the indirect approach is not a feasible solution for push-broom line cameras onboard UAVs due to the limited ability of line cameras to decouple system parameters and is confirmed with experimental results. Lastly, this research demonstrates that for frame and line camera systems, the direct approach can be fully-automated by incorporating structure from motion (SfM) based tie point features. Methods for feature detection and matching for frame and line camera systems are presented. This research also presents the necessary changes in the bundle adjustment with self-calibration to successfully incorporate a large amount of automatically-derived tie points. For frame cameras, the results show that the direct and indirect approach is capable of estimating and correcting this time delay. When a time delay exists and the direct or indirect approach is applied, horizontal accuracy of 1–3 times the ground sampling distance (GSD) can be achieved without the use of any ground control points (GCPs). For line camera systems, the direct results show that when a time delay exists and spatial and temporal calibration is performed, vertical and horizontal accuracy are approximately that of the ground sample distance (GSD) of the sensor. Furthermore, when a large artificial time delay is introduced for line camera systems, the direct approach still achieves accuracy less than the GSD of the system and performs 2.5-8 times better in the horizontal components and up to 18 times better in the vertical component than when temporal calibration is not performed. Lastly, the results show that automated tie points can be successfully extracted for frame and line camera systems and that those tie point features can be incorporated into a fully-automated bundle adjustment with self-calibration including time delay estimation. The results show that this fully-automated calibration accurately estimates system parameters and demonstrates absolute accuracy similar to that of manually-measured tie/checkpoints without the use of GCPs.</p>

碩士<br>國立臺灣大學<br>農業工程學研究所<br>87<br>It changes the rural production method and causes the countryside toward recreational development which is the important direction to the countryside and rural generation for the city and economy growing rapidly and the government joining the international organization that is like WTO etc. actively. It is overcrowded in scenic areas and the hotels in domestic after it promotes the institution of "two days off every two week". Therefore, it becomes the other choice of popular recreation that is to relax in the countryside, to enjoy in the rural and natural circumstance, and to experience the rural culture and farmstead life. It lacks the accommodation of experiencing in the rural life, so developing pension will be one method of production transformation in the future. We could detect that Taiwanese pensions lack in accordance with the regulation and administrative grade in pension''''''''s standard, so it is difficulty to find one of pensions that is forming and developed perfectly. It makes the benefit of dwelling experience of pension in rural life disappearing because numerous people have no idea of the pension''''''''s spatial arrangement awfully. Before these researches which is related to the pension were partial to the aspects of the pension''''''''s type, the pension''''''''s ordinance, and the passengers'''''''' characteristics. It makes the proprietors who want to put in developing pension being at a loss as to what to do because it lacks the study which is how to adjust the dwelling house changing into the pension. The traditional quadrangle house occupies the proportion at most in the investigation on the architectural type of pensions that the passengers anticipate (35.5%). Therefore, to take advantage of the quadrangle house to develop pension is abundantly potential to use as the natural and classical environment in rural areas in Taiwan presently. If we bring up a correct concept for the adjustment of pension''''''''s space, it can cause a brand-new style and features for the pension''''''''s development. Because of lacking the experience in this aspect in Taiwan, this thesis is from the dwelling experience of pension''''''''s space in Germany. We will analyze and review the related topics for discussion in spatial arrangement of pension. Then we make use of the traditional quadrangle house that will develop pension''''''''s space, and we can provide the correct concepts in the spatial adjustment of developing pension.

碩士<br>國立新竹教育大學<br>環境與文化資源學系碩士班<br>98<br>Taiwan passed the Wildlife Conservation Law in 1978. Although this law took into account the continuation of species, it had produced negative impacts upon the people living in the habitat. For instance, the corps was reductive by the invading of the animals and people were attacked by wild animals. The research took the fruit farmers who suffered from the hazard of Macaca cyclopis in Mt. Chai area. It aimed to investigate the lifestyle of the fruit farmers in Mt. Chai and the adjustment they made when the disaster struck them around the passage of the Wildlife Conservation Law. It also attempted to present the external driving forces beyond the Mt. Chai. The methods to carry out this study were using the qualitative approach by literature review, participant observation and interview. The data were gathered to interpret the changing life of the fruit farmers who suffered from the hazard of Macaca cyclopis, and the restrictions and considerations of the adjustment. The researcher found that human beings were the dominators of Mt. Chai area before the passage of the Wildlife Conservation Law. Though the fruit planting was a hard work, it seemed to be as they sow, so shall they reap. Macaca cyclopis did help for the fruit farmers. After the publishing of the Wildlife Conservation Law, people lost domination over this area. Macaca cyclopis became a hazard, they decreased the harvest. The fruit farmers’ responses to the hazard were carrying on the cultivation, abandoning the planting and transforming. Some fruit farmers carried on their jobs because of the difficulties of changing jobs and making a living. For the restrictions of the law and the cost, they used firecrackers and nets to keep the monkeys away. Some gave up the cultivating under the situations of poor environment, bad harvest and aging. Others changed their careers to the service industries after having adequate finance resources. The adjustment of the fruit farmers was decided by themselves theoretically, there really were still many restrictions for the fruit farmers, such as the state apparatus, economic conditions and environmental forces. That illustrated a major difference between the farmers’ expectations and the practical reality. To fight for the right to survival, farmers protested to the government by the parades, judicial proceedings and other actions. Because of problems with land rights, the restrictions of law and the intervention of environmental activists, they still didn’t find the solutions. The hazard of Macaca cyclopis isn’t resolved. Therefore, it caused a decline of local industries

Tese de doutoramento em Biociências, na especialidade de Ecologia, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra<br>The genus Corema has an amphi-atlantic distribution and includes two species: C. album, endemic to the Atlantic coast of the Iberian Peninsula and C. conradii, endemic to the Northeastern coast of North America. Both species are dioecious coastal shrubs; plant sexual dimorphism is noticeable in the floral structures and the presence of fruits in female plants. Due to the different costs of reproduction, male and female plants have different physiological requirements and performance. The main hypothesis driving this work is that sex-related differences in physiology and performance lead to demographic biases of the Corema populations and influence the interactions of male and female plants with their associated biota. Three C. album populations in the west coast of Portugal (both in sand dunes and in coastal woodlands) and three C. conradii populations in the east coast of Canada were studied. The demography of the C.album populations was characterized to identify sex related biases, and a competition/facilitation effect of C. album plants on the neighbouring flora was assessed. Adjustment of fruit maturation by female plants was investigated in the context of the serial adjustment hypothesis (Lloyd 1980). The interactions of male and female Corema plants with soil dwelling biota were investigated to assess sex-related and habitat related differences; these included nematode and fungal endophyte communities, particularly ericoid mycorrhiza (ErM), associated with the rhizosphere of both species. A possible interaction between the nematode communities and ErM colonization was investigated. Systematic male biases in sex ratios were not found in the studied C. album populations and most sampled plots showed complete spatial randomness in the distribution of the individuals of both sexes, suggesting that female plants can compensate for the higher reproductive effort they bear. Female C. album plants presented low fruit sets, but infructescences with more fruits also had larger and heavier drupes. Together with the dynamic environmental conditions and the lack of evidence of pollen limitation, this suggested the low fruit sets are the result of an adjustment of the fruit production and maturation to resource availability. Such a strategy can ensure the production of the optimal number of fruits in each season, as well as minimize the delayed costs of reproduction that accumulate along several reproductive periods, by adapting effort to the conditions of each reproductive event. As the dominant plant species in the surveyed areas, C. album canopy cover had a detrimental effect on all plant life-forms (Raunkiær 1937) except for geophytes. Sex-related differences were found in the composition and abundance of the plant parasitic nematode (PPN) communities for both Corema species. The plant phenological stage significantly influenced the abundance of free-living nematodes, PPN genera and nematode community indices in C. album. Significant sex-related differences in PPN community associated with C. album and on the abundance of three PPN genera (Criconema, Hemicriconemella and Meloidogyne) were apparent during the fruiting season but not during flowering, suggesting that interactions with the nematode community were dependent not only on plant sex but also on the phenological stage of the plant. The fungal endophyte community associated with the Corema roots included several taxa: ericoid mycorrhizal fungi, ecto mycorrhizal fungi, and dark septate endophytes. Sex-related differences were not detected in the composition, or in the diversity of the fungal endophyte community in either Corema species, nor in the percentage of colonization of the roots by ErM in C. album; plants growing in the same area had similar endophyte communities, irrespective of plant sex. The diversity of endophytes and root colonization frequency in C. album were higher during the fruiting season, but no statistical interaction between plant sex and phenological stage was detected on the root colonization frequency, indicating that ErM of C. album do not respond to changes in resource demand by the plant. Interactions between the ErM and the nematode community were only apparent during the fruiting season, when ErM colonization frequency was highest. Corema album and C. conradii are the dominant shrubs on the coastal barrens and sand dunes they inhabit. These ecosystems are of particular importance as they represent the transition between the sea shore and inland areas, protecting the productive activities inland from salt spray, winds and erosion. The present work provides the first insights to the below-ground ecology of these coastal species emphasizing the importance of an integrative perspective of the interactions among organisms for the understanding of coastal ecosystems.<br>O género Corema tem uma distribuição anfi-Atlântica e inclui duas espécies: C. album, endémica da costa Atlântica da Península Ibérica e C. conradii, endémica do Norte da costa este da América do Norte. Ambas as espécies são arbustos costeiros dióicos; o dimorfismo sexual é observável nas estruturas florais e na presença de frutos nas plantas femininas. Devido às diferenças nos custos da reprodução, machos e fêmeas têm necessidades fisiológicas e desempenhos diferentes. A hipótese principal que guia este trabalho é que diferenças fisiológicas e de desempenho, associadas ao sexo, dão origem a enviesamentos demográficos nas populações de Corema e influenciam as interações das plantas masculinas e femininas com os organismos que lhes estão associados. Foram estudadas três populações de C. album na costa oeste de Portugal (tanto na duna como no pinhal costeiro) e três populações de C. conradii na costa este do Canadá. A demografia das populações de C. album foi caracterizada para identificar enviesamentos relacionados com o sexo e foi avaliado um efeito de competição/facilitação das plantas de C. album sobre a flora associada. Investigou-se o ajustamento da maturação de frutos pelas plantas femininas no contexto da hipótese de ajustamento sequencial (Lloyd 1980). Investigaram-se as interações de plantas de Corema masculinas e femininas com organismos do solo para avaliar diferenças associadas ao sexo e ao tipo de habitat; estas incluíram as comunidades de nemátodes e de fungos endofíticos, particularmente micorrizas ericóides (ErM), associadas à rizosfera de ambas as espécies. Investigou-se uma possivel interação entre as comunidades de nemátodes e a colonização por ErM. Não se encontraram enviesamentos sistemáticos favoráveis aos machos nas populações de C. album estudadas e a maioria das parcelas amostradas apresentou uma distribuição espacial dos indivíduos de ambos os sexos completamente aleatória, sugerindo que as fêmeas são capazes compensar o esforço reprodutivo mais elevado que suportam. As plantas femininas de C. album apresentaram uma baixa produção de frutos em relação ao número de flores, mas infrutescências com mais frutos tinham drupas maiores e mais pesadas. Isto sugeriu, em conjunto com as condições ambientais dinâmicas e a falta de evidências de limitação de pólen, que os baixos números de frutos por infrutescência se devem ao ajustamento da produção e da maturação dos frutos à disponibilidade de recursos. Esta estratégia não só assegura a produção de um número ótimo de frutos em cada época reprodutiva, como minimiza os custos de reprodução acumulados ao longo de vários períodos reprodutivos, ao adaptar o esforço a cada evento de reprodução. Sendo a espécie vegetal dominante nas áreas amostradas, a cobertura por C. album teve um efeito prejudicial em todas as formas de vida vegetais (Raunkiær 1937), à excepção dos geófitos. Encontraram-se diferenças relacionadas com o sexo na composição e abundância das comunidades de nemátodes fitoparasitas (PPN) em ambas as espécies de Corema. O estado fenológico da planta influenciou significativamente a abundância de nemátodes de vida livre, géneros de PPN e os valores dos índices ecológicos das comunidades de nemátodes em C. album. Diferenças significativas relacionadas com o sexo da planta na comunidade de PPN associada a C. album e na abundância de três géneros de PPN (Criconema, Hemicriconemella e Meloidogyne) foram visíveis durante a época de frutificação, mas não durante a de floração, sugerindo que as interações com a comunidade de nemátodes dependem, não só do sexo da planta, mas também do seu estado fenológico. A comunidade de fungos endofíticos associada às raízes de Corema incluiu vários taxa: fungos que formam micorrizas ericóides, ecto-micorrizas e endófitos dark septate. Não se detetaram diferenças associadas ao sexo na composição nem na diversidade das comunidades de fungos endofíticos de qualquer das espécies de Corema, nem na percentagem de colonização das raízes de C. album por ErM; plantas que cresciam nas mesmas áreas apresentaram comunidades de endófitos semelhantes, independentemente do sexo da planta. A diversidade de endófitos e a colonização das raízes de C. album foram maiores durante a frutificação, mas não se detectou interação estatística entre o sexo da planta e o seu estado fenológico na frequência de colonização das raízes, o que indica que as ErM não respondem à variação na necessidade de recursos por parte de planta. As interações entre ErM e a comunidade de nemátodes foram detetadas apenas durante a época de frutificação, quando houve maior frequência de colonização por ErM. Corema album e C. conradii são os arbustos dominantes nas falésias e dunas costeiras que habitam. Estes ecossistemas são de particular importância já que representam a transição entre a orla costeira e as áreas interiores, protegendo as atividades produtivas do interior contra a salinidade, o vento e a erosão. Este trabalho apresenta as primeiras perspetivas sobre a ecologia da rizosfera destas duas espécies costeiras, enfatizando a importância de uma perspetiva integradora das interações entre organismos para a compreensão dos ecossistemas costeiros.

The processes involved in fluvial geomorphic adjustment to human-induced change are not well understood, despite an increasing and global prevalence of human disturbance to rivers. This doctoral dissertation research examines spatial and temporal patterns of geomorphic adjustment processes in three tributary streams of the Lower Hatchie River Basin, in west Tennessee, which are adjusting to historic land clearance and channelization. This dissertation examines (1) the types and spatial pattern of geomorphic adjustment processes in a total of 34 tributary reaches located in Richland, Jeffers, and Dry Creeks, (2) the applicability of an existing model of geomorphic adjustment for use in tributary streams with multiple episodes of disturbance, (3) sediment dynamics at the reach scale, including floodplain and channel re-coupling, and (4) the connections between reach-scale processes of sediment dynamics and systemwide geomorphic response. Results from this dissertation research suggest that after an initial period of down cutting, channel widening involving bank failure and bank undercutting are the dominant adjustment mechanisms, and create asymmetrically-shaped channels. Bank failures in the study tributaries are common and are produced by progressive bank undercutting related to redirection of flow towards banks by well-developed bars and berms deposited in the channel. The lifetime of channel bars and berms appears to be long, enduring beyond seven months of monitoring. The common occurrence of asymmetric channels and well-developed bar and berm deposits throughout each of the three study tributaries lends field-based support for the operation of bar-bend processes of lateral migration. These results highlight the important role of lateral adjustment processes postchannelization and sediment storage in determining the location of geomorphic processes and potentially initiating system-wide lateral migration. Applicability of the Channel Evolution Model may be liInited in tributary streams with mUltiple periods and/or locations ofchannelization because it focuses on the area of maximum disturbance, and it lacks explicit incorporation of lateral migration processes and sediment dynamics. Field-based sediment monitoring and simulation of sediment connectivity using channel morphometrics and Multi-Response Permutation Procedure suggest that sediment dynamics remain in a state of adjustment, lacking suitable long-term storage of sediment due to floodplain/channel de-coupling and irregular sediment transport. Analysis of a core taken from one re-coupled floodplain in Richland Creek suggests that re-coupling is possible but, in this instance, required more than 50 years to occur. This indicates that sediment will continue to be stored in the channel well into the future, potentially prolonging channel widening and lateral migration processes. Finally, results from this research suggest that spatial and temporal patterns of geomorphic adjustment depend upon reach-scale processes of sediment dynamics and flow deflection. The dominance of reach-scale dynamics in the tributaries calls into question the applicability of numerical models developed on a watershed-based approach and demonstrates the need to understand reach-scale controls ofsystem-wide response in fluvial systems.