Dt. Titel: Vorhersagemodelle für den Einfluss von Süßwasser Einstrom auf Salzwasser Schichten, Wanderbewegung und Lebenszyklen des Zooplankton im Arktischen Ozean: Szenarien und Trends in der Zukunft

Designing and implementing coupled Earth System Models (ESMs) is a challenge for climate scientists and software engineers alike. Coupled models incorporate two or more independent numerical models into a single application, allowing for the simulation of complex feedback effects. As ESMs increase in sophistication, incorporating higher fidelity models of geophysical processes, developers are faced with the issue of managing increasing software complexity. Recently, reusable coupling software has emerged to aid developers in building coupled models. Effective reuse of coupling infrastructure means increasing the number of coupling functions reused, minimizing code duplication, reducing the development time required to couple models, and enabling flexible composition of coupling infrastructure with existing constituent model implementations. Despite the widespread availability of software packages that provide coupling infrastructure, effective reuse of coupling technologies remains an elusive goal: coupling models is effort-intensive, often requiring weeks or months of developer time to work through implementation details, even when starting from a set of existing software components. Coupling technologies are never used in isolation: they must be integrated with multiple existing constituent models to provide their primary services, such as model-to-model data communication and transformation. Unfortunately, the high level of interdependence between coupling concerns and scientific concerns has resulted in high interdependence between the infrastructure code and the scientific code within a model’s implementation. These dependencies are a source of complexity which tends to reduce reusability of coupling infrastructure. This dissertation presents mechanisms for increasing modeler productivity based on improving reuse of coupling infrastructure and raising the level of abstraction at which modelers work. This dissertation argues that effective reuse of coupling technologies can be achieved by decomposing existing coupling technologies into a salient set of implementation-independent features required for coupling high-performance models, increasing abstraction levels at which model developers work, and facilitating integration of coupling infrastructure with constituent models via component-based modularization of coupling features. The contributions of this research include: (1) a comprehensive feature model that identifies the multi-dimensional design space of coupling technologies used in high-performance Earth System Models, (2) Cupid, a domain-specific language and compiler for specifying coupling configurations declaratively and generating their implementations automatically, and (3) Component-based Coupling Operators (CC-Ops), a modular approach to code reuse of coupling infrastructure based on component technologies for high-performance scientific settings. The Cupid domain-specific language is evaluated by specifying a coupling configuration for an example fluid dynamics model and measuring the amount of code generated by the Cupid compiler compared to a hand coded version. The CC-Op approach is evaluated by implementing several CC-Ops using an existing high-performance component framework and measuring performance in terms of scalability and overhead.

Cette thèse est une enquête d'histoire et de philosophie des sciences sur l'hypothèse Gaïa (HG) proposée par Lovelock et Margulis dans les années 1970. L'examen historique de l'élaboration d'HG et de sa très riche réception dans diverses disciplines scientifiques (climatologie, biogéochimie, géochimie, biologie de l'évolution, écologie et sciences de la complexité) et au sein des mouvements environnementalistes nous conduit à montrer qu'une ambiguïté majeure sur le statut d'HG grève la littérature : qu'est-ce qu'HG ? Nous montrons qu'HG a été considérée tantôt comme une hypothèse, tantôt comme une théorie, tantôt comme un programme de recherche, tantôt comme une philosophie de la nature. Chacune de ces lectures est ensuite examinée. Nous proposons une caractérisation épistémologique et historique d'HG montrant qu'HG ne doit pas être interprétée comme une hypothèse devant être confrontée de manière directe aux faits, mais comme une théorie élaborée avec des modèles. Nous clarifions alors le rôle et le statut méthodologique des modèles et théories d'HG ainsi que les concepts et hypothèses fondamentales qui les sous-tendent. La reconnaissance de Gaïa comme un système constitué des vivants et de l'environnement avec lequel ils interagissent a été l'origine de la constitution d'un nouveau programme de recherche: les sciences du système Terre. Nous proposons une histoire et une caractérisation de ce programme, repérons les déplacements philosophiques qu'il a opérés à propos des concepts de vie, d'environnement et de nature puis analysons les liens entre les conceptions que Lovelock a de Gaïa et les prescriptions environnementales qu'il a prononcées au nom de Gaïa. / The Gaia hypothesis (GH) proposed in the 1970's by Lovelock and Margulis is here analyzed from a history and philosophy of science perspective. The historical analysis of GH's elaboration and rich reception across various disciplines (climatology, biogeochemistry, geochemistry, evolutionary biology, ecology and complexity sciences) and within environmentalist movements leads me to argue that a major ambiguity plagues the relevant literatures: what is GH? I show that GH has been considered as a hypothesis, as a theory, as a research program, or as a philosophy of nature. Each of these interpretations is then analyzed. An epistemological and historical characterisation of GH shows that GH should not be interpreted as a hypothesis which ought to be confronted directly to empirical facts, but as a theory elaborated with models. I elucidate the methodological role and status of GH's models and theories before clarifying the concepts and expliciting the fundamental hypotheses underlying these models and theories. The recognition of Gaia as a system constituted of living organisms and the environment with which they internet led to the constitution of a new research program: the Earth system sciences. I offer a history and a characterisation of this research program, specify the philosophical shifts it brought about concepts such as life, the environment and nature and I analyze the relationships between Lovelock's conceptions of Gaia and the environmental prescriptions he pronounced in the name of Gaia.

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No. of bitstreams: 2 Tese - Frederico Augusto Martins Valtuille Faleiro - 2016.pdf: 7096330 bytes, checksum: 04cfce04ef128c5bd6e99ce18bb7f650 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2016-03-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The climate changes are one of the major threats to the biodiversity and it is expected to increase its impact along the 21st century. The climate change affect all levels of the biodiversity from individuals to biomes, reducing the ecosystem services. Despite of this, the prediction of climate change impacts on biodiversity is still a challenge. Overcoming these issues depends on improvements in different aspects of science that support predictions of climate change impact on biodiversity. The common practice to predict the climate change impact consists in formulate ecological niche models based in the current climate and project the changes based in the future climate predicted by the climate models. However, there are some recognized limitations both in the formulation of the ecological niche model and in the use of predictions from the climate models that need to be analyzed. Here, in the first chapter we review the science behind the climate models in order to reduce the knowledge gap between the scientific community that formulate the climate models and the community that use the predictions of these models. We showed that there is not consensus about evaluate the climate models, obtain regional models with higher spatial resolution and define consensual models. However, we gave some guidelines for use the predictions of the climate models. In the second chapter, we tested if the predictions of correlative ecological niche models fitted with presence-absence match the predictions of models fitted with abundance data on the metrics of climate change impact on orchid bees in the Atlantic Forest. We found that the presence-absence models were a partial proxy of change in abundance when the output of the models was continuous, but the same was not true when the predictions were converted to binary. The orchid bees in general will decrease the abundance in the future, but will retain a good amount of suitable sites in the future and the distance to gained climatic suitable areas can be very close, despite of great variation. The change in the species richness and turnover will be mainly in the western and some regions of southern of the Atlantic Forest. In the third chapter, we discussed the drawbacks in using the estimations of realized niche instead the fundamental niche, such as overpredicting the effect of climate change on species’ extinction risk. We proposed a framework based on phylogenetic comparative and missing data methods to predict the dimensions of the fundamental niche of species with missing data. Moreover, we explore sources of uncertainty in predictions of fundamental niche and highlight future directions to overcome current limitations of phylogenetic comparative and missing data methods to improve predictions. We conclude that it is possible to make better use of the current knowledge about species’ fundamental niche with phylogenetic information and auxiliary traits to predict the fundamental niche of poorly-studied species. In the fourth chapter, we used the framework of the chapter three to test the performance of two recent phylogenetic modeling methods to predict the thermal niche of mammals. We showed that PhyloPars had better performance than Phylogenetic Eigenvector Maps in predict the thermal niche. Moreover, the error and bias had similar phylogenetic pattern for both margins of the thermal niche while they had differences in the geographic pattern. The variance in the performance was explained by taxonomic differences and not by methodological aspects. Finally, our models better predicted the upper margin than the lower margin of the thermal niche. This is a good news for predicting the effect of climate change on species without physiological data. We hope our finds can be used to improve the predictions of climate change effect on the biodiversity in future studies and support the political decisions on minimizing the effects of climate change on biodiversity. / As mudanças climáticas são uma das principais ameaças à biodiversidade e é esperado que aumente seu impacto ao longo do século XXI. As mudanças climáticas afetam todos os níveis de biodiversidade, de indivíduos à biomas, reduzindo os serviços ecossistêmicos. Apesar disso, as predições dos impactos das mudanças climáticas na biodiversidade é ainda um desafio. A superação dessas questões depende de melhorias em diferentes aspectos da ciência que dá suporte para predizer o impacto das mudanças climáticas na biodiversidade. A prática comum para predizer o impacto das mudanças climáticas consiste em formular modelos de nicho ecológico baseado no clima atual e projetar as mudanças baseadas no clima futuro predito pelos modelos climáticos. No entanto, existem algumas limitações reconhecidas na formulação do modelo de nicho ecológico e no uso das predições dos modelos climáticos que precisam ser analisadas. Aqui, no primeiro capítulo nós revisamos a ciência por detrás dos modelos climáticos com o intuito de reduzir a lacuna de conhecimentos entre a comunidade científica que formula os modelos climáticos e a comunidade que usa as predições dos modelos. Nós mostramos que não existe consenso sobre avaliar os modelos climáticos, obter modelos regionais com maior resolução espacial e definir modelos consensuais. No entanto, nós damos algumas orientações para usar as predições dos modelos climáticos. No segundo capítulo, nós testamos se as predições dos modelos correlativos de nicho ecológicos ajustados com presença-ausência são congruentes com aqueles ajustados com dados de abundância nas medidas de impacto das mudanças climáticas em abelhas de orquídeas da Mata Atlântica. Nós encontramos que os modelos com presença-ausência foram substitutos parciais das mudanças na abundância quando o resultado dos modelos foi contínuo (adequabilidade), mas o mesmo não ocorreu quando as predições foram convertidas para binárias. As espécies de abelhas, de modo geral, irão diminuir em abundância no futuro, mas reterão uma boa quantidade de locais adequados no futuro e a distância para áreas climáticas adequadas ganhadas podem estar bem próximo, apesar da grande variação. A mudança na riqueza e na substituição de espécies ocorrerá principalmente no Oeste e algumas regiões no sul da Mata Atlântica. No terceiro capítulo, nós discutimos as desvantagens no uso de estimativas do nicho realizado ao invés do nicho fundamental, como superestimar o efeito das mudanças climáticas no risco de extinção das espécies. Nós propomos um esquema geral baseado em métodos filogenéticos comparativos e métodos de dados faltantes para predizer as dimensões do nicho fundamental das espécies com dados faltantes. Além disso, nós exploramos as fontes de incerteza nas predições do nicho fundamental e destacamos direções futuras para superar as limitações atuais dos métodos comparativos filogenéticas e métodos de dados faltantes para melhorar as predições. Nós concluímos que é possível fazer melhor uso do conhecimento atual sobre o nicho fundamental das espécies com informação filogenética e caracteres auxiliares para predizer o nicho fundamental de espécies pouco estudadas. No quarto capítulo, nós usamos o esquema geral do capítulo três para testar a performance de dois novos métodos de modelagem filogenética para predizer o nicho térmico dos mamíferos. Nós mostramos que o “PhyloPars” teve uma melhor performance que o “Phylogenetic Eigenvector Maps” em predizer o nicho térmico. Além disso, o erro e o viés tiveram um padrão filogenético similar para ambas as margens do nicho térmico, enquanto eles apresentaram diferentes padrões espaciais. A variância na performance foi explicada pelas diferenças taxonômicas e não pelas diferenças em aspectos metodológicos. Finalmente, nossos modelos melhor predizem a margem superior do que a margem inferior do nicho térmico. Essa é uma boa notícia para predizer o efeito das mudanças climáticas em espécies sem dados fisiológicos. Nós esperamos que nossos resultados possam ser usados para melhorar as predições do efeito das mudanças climáticas na biodiversidade em estudos futuros e dar suporte para decisões políticas para minimização dos efeitos das mudanças climáticas na biodiversidade.

Les activités anthropiques affectent les cycles biogéochimiques globaux, principalement par l'ajout de nutriments dans les écosystèmes. Il est donc crucial de déterminer dans quelle mesure les cycles biogéochimiques globaux peuvent être régulés. Les autotrophes peuvent réguler les réservoirs de nutriments par la consommation des ressources, mais la majorité des ressources leur sont inaccessibles à l'échelle globale. Par des modèles théoriques, nous avons cherché à évaluer la manière dont les autotrophes répondent à la fertilisation à l'échelle globale et leur capacité à réguler les concentrations des nutriments quand leur accessibilité est limitée. Nous avons également étudié les mécanismes qui déterminent la régulation des rapports de Redfield dans l'océan, ainsi que les effets de l'ajout de nutriments sur la production primaire océanique totale. Nous avons montré que les organismes ne régulent pas efficacement les réservoirs de nutriments. Le couplage des cycles biogéochimiques et la compétition entre groupes fonctionnels peuvent altérer, négativement ou positivement, la régulation des cycles biogéochimiques globaux par les organismes. Une régulation inefficace des concentrations de nutriments n'exclut par contre pas une forte régulation des rapports entre ces nutriments, comme dans le cas des rapports de Redfield. La fertilisation des écosystèmes terrestres et océaniques risque donc de fortement impacter la production primaire et les cycles biogéochimiques globaux, à de courtes comme à de grandes échelles de temps. / Anthropogenic activities heavily impact global biogeochemical cycles, mainly through nutrient fertilisation of ecosystems; thus it is crucial to assess the extent to which global biogeochemical cycles are regulated. Autotrophs can regulate nutrient pools locally through resource consumption, but most resources are inaccessible to them at global scales. We used theoretical models to assess how organisms respond nutrient fertilisation at global scales and how they can regulate the concentration of these nutrients when their accessibility of is limited. We further investigated the mechanisms driving the regulation of Redfield ratios in oceans, and the effects of nutrient fertilisation on total oceanic primary production. We showed that organisms cannot efficiently regulate nutrient pools. Mechanisms such as coupling of nutrient cycles and competition between functional groups can alter the strength of biotic regulation of global biogeochemical cycles, either positively or negatively. An inefficient regulation of inaccessible nutrient concentration, however, does not exclude a strong biotic regulation of nutrient ratios, as is the case with Redfield ratios in oceans. Nutrient fertilization of oceanic and terrestrial ecosystems is thus likely to have a strong impact on primary production and global nutrient cycles at both small and long timescales.

Previous research connecting scientific knowledge production with governing of the global environment usually start in international climate change negotiations and related assessments. From that vantage point Earth system science and models are studied as an expansion of Global Circulation Models. By tracing of the history of the present Earth system outlook this thesis offers a reflection about how scientific knowledge produce and connects problems with descriptions of desired order of things and strategies to get there. Knowledge becomes a productive power by shaping fields of possible action in relation to the global environment. The interpreted empirical material consists of scientific discussions from the International global environmental change programmes and particularly the International Geosphere-Biosphere Programme (IGBP) and the International Human Dimensions Programme on global environmental change (IHDP). The studied period spans from the start of the planning of the IGBP in 1983 to the presentation of the new research programme Future Earth in 2013. The thesis is organised around the effects of the IGBP’s strategy to use predictive Earth system models as a tool to bring a broad range of scientific disciplines together. The results demonstrate the historicity of the present Earth system outlook by showing how ecosystems and human dimensions were attributed new and more important roles as drivers of global change. The thesis also argue for the need to approach the ‘Earth system’ as a result of a productive tension between top-down perspectives found in global modelling and bottom-up empirical research engaging with process interactions down to local scales. / Genom att studera diskussioner inom internationella miljöforskningsprogram spårar den här avhandlingen framväxten av dagens syn på planeten jorden som ett sammanlänkat system – Jordsystemet. Kopplingen mellan makt och kunskap, styrning och mentaliteter, ligger till grund för studiens tolkande ansats. Den knyter samman sätt att betrakta och beräkna den globala miljön, grunden för jordsystemperspektivet, och de handlingsalternativ det synliggör inom politik och vetenskap. Studien baseras primärt på analyser av arkivmaterial från International Geosphere-Biosphere Programme (IGBP) och International Human Dimensions Programme of Global Environmental Change (IHDP). Tillsammans representerar dessa två program ett brett nätverk för forskning om globala miljöförändringar. Den undersökta perioden startar i och med planeringen av IGBP 1983 och avslutas 2013 med att Future Earth etableras som ett nytt internationellt program för forskning om globala miljöförändringar. Avhandlingen undersöker effekter av IGBPs strategi att använda prediktiva Jordsystemmodeller som ett redskap för att integrera och koordinera forskningen om globala miljöförändringar. Studiens resultat visar på historiciteten i nuvarande sätt att betrakta Jordsystemet. Framförallt studeras hur introducerandet av ekologisk och social komplexitet i förståelsen och modelleringen av Jordsystemet hänger samman med en förändrad bild av relationen människa-miljö och därmed också bilden av globala miljöförändringar som vetenskapligt och politiskt problem. Avhandlingen visar att förståelsen av Jordsystemet vuxit fram i en produktiv spänning mellanovanifrånperspektivet i globala modeller och lokalt förankrad socio-ekologisk interaktion.

This thesis examines the readiness and perception in the regions of Gothenburg and Bremen towards future sea level rise. It does so through the theoretical lens of risk psychology / policy research and of climate science research. Results are built on some of the most recent research of these fields, as well as interviews with 14 people on the local, regional and national level in Germany and Sweden. Key findings of this thesis are that both contexts struggle to deal with the great uncertainties inherent in sea level rise. On the German North Sea coast, there is long experience with sea level variation and extensive civil institutions created to deal with storm surges, dikes and sea level rise which may partially compensate for inherent vulnerability to future sea level rise in this region. The novelty of sea level rise in Gothenburg and Sweden means that it is in the process of creating similar institutions and national-regional divisions of responsibility from scratch. The great uncertainty around the pace and extent of future sea level rise is however an obstacle which may have to be overcome before a more coherent response may be developed. / Denna uppsats undersöker beredskap och uppfattningar kring framtida havsnivåhöjningar i Göteborg och Bremen. Detta görs med de teoretiska ansatserna riskpsykologi / beslutspsykologi och grundläggande klimatvetenskap. Uppsatsens resultat bygger på de senaste resultaten inom dessa fält, samt intervjuer med 14 personer på lokal, regional och nationell nivå i Tyskland och Sverige. Efter genomförd studie kan konstateras att bägge kontext har svårigheter att hantera de stora osäkerheter som havsnivåhöjningen medför. Tyska Nordsjökusten har mycket lång erfarenhet och kapabla offentliga institutioner vilka skapats för att hantera skyddsvallar, sjunkande landnivåer och stormfloder, vilket balanserar det prekära läge som området annars står inför. I Göteborg och i Sverige är havsnivåhöjning något fundamentalt nytt, vilket innebär att man nu försöker skapa liknande institutioner och ansvarsfördelning mellan nationellt och regionalt som de Bremen och Tyskland redan har. Ett hinder för detta är de stora osäkerheter som råder kring hastighet och absolut nivå på framtida havsnivåhöjningar. Dessa osäkerheter kan komma behöva reduceras innan problemet börjar hanteras på ett mer samordnat sätt.

Forests affect climate by absorbing CO₂ but also by altering albedo, latent heat flux, and sensible heat flux. In this study we used the Community Earth System Model to assess the biophysical effect of North American temperate forests on climate and how this effect changes with location, tree type, and forest management. We calculated the change in annual temperature and energy balance associated with afforestation with either needle leaf evergreen trees (NET) or broadleaf deciduous trees (BDT) and between forests with high and low leaf-area indices (LAI). Afforestation from crops to forests resulted in lower albedo and higher sensible heat flux but no consistent difference in latent heat flux. Forests were consistently warmer than crops at high latitudes and colder at lower latitudes. In North America, the temperature response from afforestation shifted from warming to cooling between 34° N and 40° N for ground temperature and between 21° N and 25° N for near surface air temperature. NET tended to have lower albedo, higher sensible heat flux and warmer temperatures than BDT. The effect of tree PFT was larger than the effect of afforestation in the south and in the mid-Atlantic. Increasing LAI, a proxy for increased management intensity, caused a cooling effect in both tree types, but NET responded more strongly and albedo decreased while albedo increased for BDT. Our results show that forests' location, tree type, and management intensity can have nearly equal biophysical effects on temperature. A forest will have maximum biophysical cooling effect if it is in the south, composed of broadleaf PFT, and is managed to maximize leaf area index. / Master of Science

Vom Standpunkt des Physikers aus gesehen, ist die Erde ein dynamisches System von großer Komplexität. Funktionale Netzwerke werden aus Beobachtungs-, und Modelldaten abgeleitet oder aufgrund theoretischer Überlegungen konstruiert. Indem sie statistische Zusammenhänge oder kausale Wirkbeziehungen zwischen der Dynamik gewisser Objekte, z.B. verschiedenen Sphären des Erdsystems, Prozessen oder lokalen Feldvariablen darstellen, bieten funktionale Netzwerke einen natürlichen Ansatz zur Bearbeitung fundamentaler Probleme der Erdsystemanalyse. Dazu gehören Fragen nach dominanten, dynamischen Mustern, Telekonnektionen und Rückkopplungsschleifen in der planetaren Maschinerie, sowie nach kritischen Elementen wie Schwellwerten, sogn. Flaschenhälsen und Schaltern im Erdsystem. Der erste Teil dieser Dissertation behandelt die Theorie komplexer Netzwerke und die netzwerkbasierte Zeitreihenanalyse. Die Beiträge zur Theorie komplexer Netzwerke beinhalten Maße und Modelle zur Analyse der Topologie (i) von Netzwerken wechselwirkender Netzwerke und (ii) Netzwerken mit ungleichen Knotengewichten, sowie (iii) eine analytische Theorie zur Beschreibung von räumlichen Netzwerken. Zur Zeitreihenanalyse werden (i) Rekurrenznetzwerke als eine theoretisch gut begründete, nichtlineare Methode zum Studium multivariater Zeitreihen vorgestellt. (ii) Gekoppelte Klimanetzwerke werden als ein exploratives Werkzeug der Datenanalyse zur quantitativen Charakterisierung der komplexen statistischen Interdependenzstruktur innerhalb und zwischen distinkten Feldern von Zeitreihen eingeführt. Im zweiten Teil der Arbeit werden Anwendungen zur Detektion von dynamischen Übergängen (Kipppunkten) in Zeitreihen, sowie zum Studium von Flaschenhälsen in der atmosphärischen Zirkulationsstruktur vorgestellt. Die Analyse von Paläoklimadaten deutet auf mögliche Zusammenhänge zwischen großskaligen Veränderungen der afrikanischen Klimadynamik während des Plio-Pleistozäns und Ereignissen in der Menschheitsevolution hin. / The Earth, as viewed from a physicist''s perspective, is a dynamical system of great complexity. Functional complex networks are inferred from observational data and model runs or constructed on the basis of theoretical considerations. Representing statistical interdependencies or causal interactions between objects (e.g., Earth system subdomains, processes, or local field variables), functional complex networks are conceptually well-suited for naturally addressing some of the fundamental questions of Earth system analysis concerning, among others, major dynamical patterns, teleconnections, and feedback loops in the planetary machinery, as well as critical elements such as thresholds, bottlenecks, and switches. The first part of this thesis concerns complex network theory and network-based time series analysis. Regarding complex network theory, the novel contributions include consistent frameworks for analyzing the topology of (i) general networks of interacting networks and (ii) networks with vertices of heterogeneously distributed weights, as well as (iii) an analytical theory for describing spatial networks. In the realm of time series analysis, (i) recurrence network analysis is put forward as a theoretically founded, nonlinear technique for the study of single, but possibly multivariate time series. (ii) Coupled climate networks are introduced as an exploratory tool of data analysis for quantitatively characterizing the intricate statistical interdependency structure within and between several fields of time series. The second part presents applications for detecting dynamical transitions (tipping points) in time series and studying bottlenecks in the atmosphere''s general circulation structure. The analysis of paleoclimate data reveals a possible influence of large-scale shifts in Plio-Pleistocene African climate variability on events in human evolution.

數位學習是透過網際網路終身學習的管道之一，透過網際網路提供數位學習，讓人們可以不受時空的限制得以在教育學習上得到數位圖書館為數位學習帶來豐富的學習素材。 本研究採用個案研究法，選擇美國國會圖書館的學習網(American Memory之Learning Page)、美國地球數位圖書館的地球系統教育(DLESE)以及我國淡水河溯源數位博物館為個案研究對象，研究目的在探討數位圖書館學習網站在教育學習的應用及其數位學習架構，包括探究數位圖書館之意涵、特色與應用、數位學習的意涵與發展、數位學習架構的要件與設計、數位圖書館學習架構之模式，並進一步對我國數位圖書館學習網站發展提出建議，最後根據研究結果提出「數位圖書館學習模式芻議」。 根據研究結果提出數位圖書館學習模式芻議，此模式可分成兩大部分，分別為數位圖書館的部分以及數位學習網站的部分。數位圖書館數位學習架構歸納十大項，根據本論文之歸納分析，將數位圖書館數位學習架構分成十大項，分別為：(1)數位圖書館特質；(2)數位館藏；(3)數位物件；(4)Metadata；(5)資訊檢索；(6)數位學習目的與特色；(7)教學系統；(8)學習系統；(9)管理系統；(10)數位學習與數位圖書館整合等。 本研究建議：(1)從事數位圖書館學習系統總體性規劃及策略，以有效整合數位資源並進行整體化建設；(2)重視數位資源之組織與互通性研究，建立全國數位圖書館聯盟管理單位；(3)擴大數位圖書館資源共享合作服務範圍，凝聚共識與團隊力，共同建立數位圖書館學習系統的功能，結合各方資源，將數位資源發揮至最大的效益；(4)由政府單位規劃中長期的數位圖書館學習系統之發展計畫，長期而持續與推動，並且培育專門的人才。 / Digital library is studied to pass on the internet network lifetime study channels, offer the digit to study through the internet network, let people not be restricted by space-time and be educating in study to receive the digital library to study for the digit bring the abundant study material. The method of case study was used, choose the Library of Congress American Memory’s Learning Page, Digital Library for Earth System Education, and the Digital Museum of Discovery of Tamsui River were used as the case research subjects. The purpose of the study is to understand the digital library studies websites and educates the application, and several in education and study structure, including probe into the meaning of the digital library, characteristic with use, several meaning of study and develop, several between important document and design, digital library to study structure study, and study website’s development and put forward the suggestion on the digital library of our country further. Then proposing the digital library study preliminary model from the result. According to the result of the study, it provided a digital library study preliminary model, this model can divide into two major parts, first parts of the digital library and second parts of studying websites respectively. Several digital libraries study structure and sum up ten great one, analyze according to the summing up of this thesis, study the structure on several of digital libraries to divide into ten great one, including: (1)Speciality of digital library; (2)The digit hall hides; (3)Digit things; (4)Metadata; (5)Information retrieval; (6)Study the purpose and characteristic in digit; (7)Tutoring system ; (8)Study the system; (9)Administrative system; (10)The digit is studied and combined etc. with the digital library. This study is proposed: (1)Engaged in digital library learn system getting overall planning and tactics, by combining several resources and carrying on whole construction effectively; (2)Pay attention to several organization of resource and general character study each other , set up national digital library alliance management unit; (3)Expand the cooperative service range of resource-sharing of digital library, condense common understanding and group's strength , set up the digital library and study the systematic function together, combine each side resource, give play to several resources to the greatest benefit; (4)The government unit plans the medium and long-term digital library and study the systematic development plan, sustain and promote for a long time, and foster special talents.