Dissertations / Theses on the topic 'Landscape structure'

This theoretically focused thesis investigates the use of soft classification techniques for identifying and quantifying landscape structures in a real landscape (the forest-savannah intergrade in the Beni savannahs, Bolivia). Two soft classification approaches are used in this study: a Semantic Import Model and a Fuzzy Clustering Model. Landscape structures usually are measured using hard classifications and quantified with landscape metrics. However previous research has highlighted problems with the interpretation and reliability of the resulting metric values. Soft classification techniques are more suitable than hard classification techniques for describing landscapes because they can model the internal inconsistencies and vague boundary transitions (ecotones) between patches of landcover that are common in semi-natural landscapes. The `uncertainty' associated with a landcover classification, ignored in hard classifications, was found to contain information about spatial structures such as ecotones. In this work the uncertainty was quantified through the use of a-cuts and landscape metrics. The results show that the soft classifications provide an additional level of information to approaches using hard classifications. The uncertainty was used to map the structure of ecotones which allows: the spatial distribution of ecotones between combinations of landcovers to be visualised; change in landscape structure to be quantified specific to the chosen combination of landcovers. This provides a more detailed and informative analysis of landscape structure and change, especially relevant in semi-natural landscapes characterised by extensive ecotones. In combination with landscape metrics, such mapping techniques improve the ability of landscape ecologists to quantify uncertain landscape structure. Further research is required to establish the ecological relevance of the landscape structures derived from uncertainty information.

This is a study in which landscape architecture is theoretically related to the "textile art." It establishes a theoretical analogy of the landscape as a kind of textual manifestation, "the landscape is a textile," and aims to establish new resemblances that show how the landscape and textile arts are related, not only with regards to the elements of composition, or to similarities between the elemental relationships that exist in both these arts, but to how the study of structure and form in the production of textiles may influence our understanding of the textile nature of the landscape. The first part of the research is developing a theoretical analogy between landscape and fabric. The process of making textiles is based on weaving and knitting, operations in which knots obviously play a most important role. The context of the urban landscape can also be viewed as a woven fabric of different threads, where knots are the summit of this interwoven textile. This study shows that the goal of landscape is to knit together the clusters of meaning so that the person can experience the unity that binds up these different qualities. Based on this theoretical analogy, the second part uses the "action research" method which in the context of this study would be a scholarly practice of design, "design-research." Both parts of the research are qualitative inquiry in nature and the qualitative manner of the investigation calls for an inductive investigation rather than a deductive one; theoretical discussions and the design section rely heavily on interpretation of the researcher.
Master of Landscape Architecture

Thesis (M.S.)--University of Florida, 1999.
Title from first page of PDF file. Document formatted into pages; contains viii, 35 p.; also contains graphics. Vita. Includes bibliographical references (p. 27-34).

The influence of habitat loss on biodiversity is related to a set of non-linear processes, which strongly affect isolation and connectivity and determine both extinction and colonization rates. Landscape changes due anthropogenic disturbances are driving not only species loss per se, but also loss of functions performed by those species, which could have important impacts on the provision of ecosystem services and ecosystem function. The objective of this dissertation is to move beyond our current understanding about landscape processes underpinning bird persistence and avian-mediated pest control in fragmented landscapes. In chapter 1, we systematically review the empirical evidence of landscape structure effects on avian-mediated pest control in agricultural systems worldwide in order to point out the main landscape processes underpinning ecosystem service provision and gaps in knowledge where research efforts should be focused. We have found 226 bird species that provide pest regulation worldwide, and a substantial proportion of those are native habitat-dependent species in tropical systems. Moreover, more heterogeneous landscapes, increased habitat amount, and decreased isolation among patches are positively associated with increased avian-mediated pest control rates. Then, using bird data collected in fragmented landscapes in the Brazilian Atlantic forest, in chapter 2 we test for community-level extinction thresholds across a range of biodiversity indices (taxonomic, functional, and phylogenetic diversity) in order to evaluate how much habitat is need to maintain sustainable ecosystem functioning and ecosystem resilience, and how matrix composition might affect these thresholds. In general, we have found that more permeable matrices are able to postpone species loss in fragmented landscapes. However, since habitat loss reaches 20% of habitat remaining, all aspects of biodiversity are compromised. Finally, in chapter 3 we investigate the cross-habitat spillover process - one of the main processes regulating avian-mediated pest control in tropical regions. Matrix composition is a key factor in facilitating species movement into matrices, as 24% of the species pool can spill over into coffee plantations, while spillover into pasture is nearly non-existent. Moreover, the interaction between forest cover and edge density is an important predictor of spillover when habitat amount is low. Our results suggest that landscape configuration and matrix composition should be considered when planning agricultural landscapes in order to ensure long-term persistence of biodiversity and ecosystem services provision
O efeito da perda de habitat sobre a biodiversidade está ligado a um conjunto de processos não-lineares que fortemente afetam a conectividade e o isolamento da paisagem, e determinam taxas de extinção e colonização. Mudanças na estrutura da paisagem desencadeadas por distúrbios antropogênicos levam não somente à perda de espécies per se, mas também a perda de funções que estas espécies desempenham no ecossistema, com importantes implicações em termos de funcionalidade e provisão de serviços ecossistêmicos. O objetivo geral desta tese é elucidar os processos, que ocorrem no nível da paisagem, que modulam a persistência de aves e, consequentemente, as funções destas aves na provisão do controle de pragas em paisagens fragmentadas. No primeiro capítulo da tese, nós revisamos sistematicamente as evidências empíricas dos efeitos da estrutura da paisagem sobre o controle de pragas provido por aves em sistemas agrícolas ao redor do mundo, identificando os processos, no nível da paisagem, subjacentes a este controle e as lacunas de conhecimento onde futuros esforços devem ser concentrados. Identificamos 226 espécies de aves provendo controle de pragas em sistemas agrícolas, sendo que uma porção substancial destas espécies em sistemas tropicais são dependentes de habitats nativos. Em geral, paisagens mais heterogêneas, com elevada cobertura de habitat nativo e menor isolamento entre fragmentos estão positivamente relacionados com elevadas taxas de controle de pragas provido por aves. Por conseguinte, no segundo capítulo, usamos dados de aves em paisagens fragmentadas emersas em diferentes contextos de matriz agrícola na Mata Atlântica brasileira, para testar limiares de extinção ao nível de comunidade. Foram usadas diferentes métricas de diversidade biológica (taxonômica, funcional e filogenética), com o intuito de avaliar o quanto de habitat é necessário para garantir o funcionamento e resiliência do ecossistema. Nós encontramos que matrizes mais permeáveis são capazes de postergar a perda de espécies em paisagens fragmentadas, no entanto, quando a perda de habitat alcança o limiar crítico de 20%, todos os aspectos da biodiversidade estão comprometidos, independentemente do tipo de matriz. Por fim, no capítulo 3, nós investigamos o processo de \'transbordamento\' (i.e. spillover), um dos principais processos reguladores da provisão do serviço de controle de pragas pela biota dependente de habitats nativos. Nós demonstramos que a composição da matriz é um fator determinante facilitando o movimento de espécies para as matrizes agrícolas, sendo que 24% do pool de espécies consegue utilizar matrizes de cafezal, enquanto este movimento é quase inexistente em matrizes de pastagem. Ademais, em paisagens com pouca cobertura florestal, a interação entre cobertura florestal e densidade de borda é um importante preditivo do spillover. Nossos resultados sugerem que a configuração da paisagem e a composição da matriz devem ser consideradas no planejamento de paisagens agrícolas para garantir a persistência em longo prazo da biodiversidade e a provisão de serviços ecossistêmicos

Floodplains are amongst the most productive and biodiverse ecosystems. The structure and functioning of floodplains is controlled by the interaction of intermittent inundation with the floodplain landscape. These interactions create highly complex and dynamic ecosystems that are difficult to study at large scales. Consequently, most research of floodplains has been conducted at small spatial and temporal scales. Inundation of floodplains can extend over many square kilometres, however, which unifies the floodplain landscape into an integrated ecosystem operating at the landscape scale. The lack of data and poor understanding of the landscape-scale structure and functioning of floodplains limits the possibility of managing floodplains sustainably as pressure for exploitation of their resources increases. This thesis quantifies the landscape-scale relationship between the frequency and patterns of inundation, the composition and structure of the landscape, and the functioning of the floodplain landscape in terms of the distribution and dynamics of plant growth vigour over an area of approximately 376,000 ha on the Lower Balonne Floodplain; highly biodiverse, semi-arid floodplain ecosystem that straddles the state border between New South Wales and Queensland approximately 500 km inland from the eastern coast of Australia. Mean annual rainfall at St.George, to the north of the study area, is approximately 400�450 mm per year, and median annual evaporation is approximately 2000 mm per year. Plants and animals on the floodplain are therefore heavily dependent upon flooding for survival. This project is based on the analysis of 13 Landsat Thematic Mapper satellite images captured over a 10-year period during which land and water resource development increased substantially. There is now concern that development activities have affected the functioning of the floodplain to the detriment of the natural environment and agricultural productivity. The impacts from these activities on the functioning of the floodplain are not yet known, however. Inundation of the Lower Balonne Floodplain was mapped using a two-part process involving a band ratio to identify deep clear water, and a change detection analysis to identify areas of shallower inundation. This analysis shows that, in contrast with most floodplains, the main flowpath of the Lower Balonne Floodplain runs along its central axis away from river channels, which flow along the floodplain�s outer edges. Inundation propagates from the centre of the floodplain out towards river channels as flood discharge volumes increase. Variations in the spatial pattern of inundated patches within the inundated extent create distinctive aquatic habitat and connectivity conditions at different flow levels. These can be described in terms of three connectivity phases: (I) Disconnected, in which isolated patches of inundation occur at low flows and river channels are hydrologically dislocated from the floodplain; (II) Interaction, where increased hydrological connectivity between inundated patches, and between the floodplain and the river channels at moderate flows, may enable significant exchange of materials, organisms and energy; and (III) Integration, in which almost the entire floodplain landscape is connected by open water during large magnitude floods. There is an abrupt transition in inundation patterns as flows increase between 60,000 ML day-1 and 65,000 ML day-1 (ARI 2 to 2.3 years) in which inundation patterns transform from being relatively disconnected into a highly integrated network of patches. These patterns may have significant consequences for the structure and functioning of the floodplain. Increases in flows across this small range may therefore mark an important ecological flow threshold on this system. Water resource development impacts have changed the relative frequency of flows on the Lower Balonne Floodplain, which will probably affect the sequence of connectivity phases over time. The most likely impact of these changes will be to create a floodplain that is drier overall than under natural flow conditions, and that has a smaller and wetter area of high inundation frequency. The relationship between inundation and the structure of the floodplain landscape was examined by comparing a landcover map showing the distribution and character of 10 landcover types to the inundation frequency maps. Landcover types were mapped from a multi-date Reference Image composite of seven images captured over a period of 10 years. The Reference Image improves landcover discrimination by at least 14% over classification of a single-date image, and has an overall accuracy between 82.5% and 85% at the landscape-scale. The Reference Image shows that the landscape of the Lower Balonne Floodplain is a highly fragmented mosaic of diverse landcover types distributed in association with inundation frequency. Stratifying the floodplain into zones of frequent and rare inundation shows that frequently inundated areas have a less fragmented but less diverse landscape structure than rarely inundated areas. Assessment of the functioning of each landcover types within the floodplain ecosystem, based on landscape pattern metric analysis, indicates that the function of landcover types also changes between inundation frequency zones. Most importantly, these changes include a transformation of the matrix landcover type, which controls the character and dynamics of the ecosystem overall, from Open Grassland to Coolibah Open Woodland in the frequently inundated zone. The landscape structure of the Lower Balonne Floodplain has been affected by development impacts, which include clearing of native vegetation, isolation of parts of the floodplain from natural inundation events by the construction of levee banks and drainage channels, and grazing impacts. Changes to the inundation regime may also affect the structure of the floodplain landscape. Over the long term, these changes are likely to create a larger area of Open Grassland and a smaller area of Coolibah Open Woodland as the zone of frequent inundation becomes smaller and wetter. To examine the functioning of the floodplain ecosystem, the inundation maps were compared to remotely sensed indexes of plant growth vigour at the landscape and landcover-type scales. The dynamics of plant growth vigour over time are influenced by factors operating at the regional, landscape and patch scales. Evaporation is the major control of growth vigour levels at the landscape scale, but each landcover type has a distinctive pattern of growth vigour dynamics that is related to its composition and location, and possibly its landscape structure. The association between the spatial distribution of plant growth vigour and inundation frequency is non-linear, with the highest growth vigour occurring where inundation occurs approximately once per year. This indicates a subsidy-stress interaction with water in which plant growth vigour is limited by soil anoxia in areas of frequent or long term inundation, and by drought stress in rarely inundated areas. A landscape-scale model of growth vigour dynamics, founded on the principles of Hierarchical Patch Dynamics and Landscape Ecology, was created from growth vigour measurements of each landcover type over time. This model was used to examine possible impacts of development activities on the functioning of the floodplain ecosystem. This model shows that the response of plant growth vigour development activities can be complex and subtle, and include a change in mean long-term growth vigour and an increased susceptibility to drought. The model also indicates that periods of high growth vigour can occur in substantially altered floodplain ecosystems. The model was also used to explore the levels of landcover change that might cause a threshold change in the functioning of the ecosystem, which may substantially alter the disturbance-response characteristics of the floodplain ecosystem. The model indicates a threshold change when the extent of Open Grassland is reduced by 30% of its extent in 1993, in which plant growth vigour response to disturbance is virtually inverted from that observed in the images. The temporal variability of plant growth vigour levels increases as the extent of Open Grassland is further reduced. This thesis makes a number of important contributions to our understanding of floodplain structure and functioning. It includes the development of new techniques suited to studying large diverse and complex landscapes at the landscape scale from satellite images, and provides quantitative data describing the links between the structure of floodplain landscapes and their functioning at the landscape scale. This work improves the understanding of floodplain ecosystems by integrating models of floodplain structure and functioning, which have been developed largely from smaller-scale studies of temperate and tropical floodplains, with landscape-scale measurements of this semi-arid system. This thesis also has implications for the Lower Balonne Floodplain by improving the level of information about this important ecosystem and providing baseline data against which the condition of the floodplain can be assessed in future.

Thesis (Ph. D.)--University of Canberra, 2004.
Title from PDF title page (viewed on July 20, 2005). Pages 185-194 lacking in digital version of thesis. Includes bibliographical references (p. 155-184).

Habitat variation is considered as an expression of biodiversity at landscape level in addition to genetic variation and species variation. Thus, effective methods for measuring habitat pattern at landscape level can be used to evaluate the status of biological conservation. However, the commonly used model (i.e. patch-corridor-matrix) for spatial pattern analysis has deficiencies. This model assumes discrete structures within the landscape without explicit consideration of “transitional zones” or “gradients” between patches. The transitional zones, often called “ecotones”, are dynamic and have a profound influence on adjacent ecosystems. Besides, this model takes landscape as a flat surface without consideration of the third spatial dimension (elevation). This will underestimate the patches’ size and perimeter as well as distances between patches especially in mountainous regions. Thus, the mosaic model needs to be adapted for more realistic and more precise representation of habitat pattern regarding to biodiversity assessment. Another part of information that has often been ignored is “small biotopes” inside patches (e.g. hedgerows, tree rows, copse, and scattered trees), which leads to within-patch heterogeneity being underestimated. The present work originates from the integration of the third spatial dimension in land-cover classification and landscape structure analysis. From the aspect of data processing, an integrated approach of Object-Based Image Analysis (OBIA) and Pixel-Based Image Analysis (PBIA) is developed and applied on multi-source data set (RapidEye images and Lidar data). At first, a general OBIA procedure is developed according to spectral object features based on RapidEye images for producing land-cover maps. Then, based on the classified maps, pixel-based algorithms are designed for detection of the small biotopes and ecotones using a Normalized Digital Surface Model (NDSM) which is derived from Lidar data. For describing habitat pattern under three-dimensional condition, several 3D-metrics (measuring e.g. landscape diversity, fragmentation/connectivity, and contrast) are proposed with spatial consideration of the ecological functions of small biotopes and ecotones. The proposed methodology is applied in two real-world examples in Germany and China. The results are twofold. First, it shows that the integrated approach of object-based and pixel-based image processing is effective for land-cover classification on different spatial scales. The overall classification accuracies of the main land-cover maps are 92 % in the German test site and 87 % in the Chinese test site. The developed Red Edge Vegetation Index (REVI) which is calculated from RapidEye images has been proved more efficient than the traditionally used Normalized Differenced Vegetation Index (NDVI) for vegetation classification, especially for the extraction of the forest mask. Using NDSM data, the third dimension is helpful for the identification of small biotopes and height gradient on forest boundary. The pixel-based algorithm so-called “buffering and shrinking” is developed for the detection of tree rows and ecotones on forest/field boundary. As a result the accuracy of detecting small biotopes is 80 % and four different types of ecotones are detected in the test site. Second, applications of 3D-metrics in two varied test sites show the frequently-used landscape diversity indices (i.e. Shannon’s diversity (SHDI) and Simpson’s diversity (SIDI)) are not sufficient for describing the habitats diversity, as they quantify only the habitats composition without consideration on habitats spatial distribution. The modified 3D-version of Effective Mesh Size (MESH) that takes ecotones into account leads to a realistic quantification of habitat fragmentation. In addition, two elevation-based contrast indices (i.e. Area-Weighted Edge Contrast (AWEC) and Total Edge Contrast Index (TECI)) are used as supplement to fragmentation metrics. Both ecotones and small biotopes are incorporated into the contrast metrics to take into account their edge effect in habitat pattern. This can be considered as a further step after fragmentation analysis with additional consideration of the edge permeability in the landscape structure analysis. Furthermore, a vector-based algorithm called “multi-buffer” approach is suggested for analyzing ecological networks based on land-cover maps. It considers small biotopes as stepping stones to establish connections between patches. Then, corresponding metrics (e.g. Effective Connected Mesh Size (ECMS)) are proposed based on the ecological networks. The network analysis shows the response of habitat connectivity to different dispersal distances in a simple way. Those connections through stepping stones act as ecological indicators of the “health” of the system, indicating the interpatch communications among habitats. In summary, it can be stated that habitat diversity is an essential level of biodiversity and methods for quantifying habitat pattern need to be improved and adapted to meet the demands for landscape monitoring and biodiversity conservation. The approaches presented in this work serve as possible methodical solution for fine-scale landscape structure analysis and function as “stepping stones” for further methodical developments to gain more insights into the habitat pattern
Die Lebensraumvielfalt ist neben der genetischen Vielfalt und der Artenvielfalt eine wesentliche Ebene der Biodiversität. Da diese Ebenen miteinander verknüpft sind, können Methoden zur Messung der Muster von Lebensräumen auf Landschaftsebene erfolgreich angewandt werden, um den Zustand der Biodiversität zu bewerten. Das zur räumlichen Musteranalyse auf Landschaftsebene häufig verwendete Patch-Korridor-Matrix-Modell weist allerdings einige Defizite auf. Dieses Modell geht von diskreten Strukturen in der Landschaft aus, ohne explizite Berücksichtigung von „Übergangszonen“ oder „Gradienten“ zwischen den einzelnen Landschaftselementen („Patches“). Diese Übergangszonen, welche auch als „Ökotone“ bezeichnet werden, sind dynamisch und haben einen starken Einfluss auf benachbarte Ökosysteme. Außerdem wird die Landschaft in diesem Modell als ebene Fläche ohne Berücksichtigung der dritten räumlichen Dimension (Höhe) betrachtet. Das führt dazu, dass die Flächengrößen und Umfänge der Patches sowie Distanzen zwischen den Patches besonders in reliefreichen Regionen unterschätzt werden. Daher muss das Patch-Korridor-Matrix-Modell für eine realistische und präzise Darstellung der Lebensraummuster für die Bewertung der biologischen Vielfalt angepasst werden. Ein weiterer Teil der Informationen, die häufig in Untersuchungen ignoriert werden, sind „Kleinbiotope“ innerhalb größerer Patches (z. B. Feldhecken, Baumreihen, Feldgehölze oder Einzelbäume). Dadurch wird die Heterogenität innerhalb von Patches unterschätzt. Die vorliegende Arbeit basiert auf der Integration der dritten räumlichen Dimension in die Landbedeckungsklassifikation und die Landschaftsstrukturanalyse. Mit Methoden der räumlichen Datenverarbeitung wurde ein integrierter Ansatz von objektbasierter Bildanalyse (OBIA) und pixelbasierter Bildanalyse (PBIA) entwickelt und auf einen Datensatz aus verschiedenen Quellen (RapidEye-Satellitenbilder und Lidar-Daten) angewendet. Dazu wird zunächst ein OBIA-Verfahren für die Ableitung von Hauptlandbedeckungsklassen entsprechend spektraler Objekteigenschaften basierend auf RapidEye-Bilddaten angewandt. Anschließend wurde basierend auf den klassifizierten Karten, ein pixelbasierter Algorithmus für die Erkennung von kleinen Biotopen und Ökotonen mit Hilfe eines normalisierten digitalen Oberflächenmodells (NDSM), welches das aus LIDAR-Daten abgeleitet wurde, entwickelt. Zur Beschreibung der dreidimensionalen Charakteristika der Lebensraummuster unter der räumlichen Betrachtung der ökologischen Funktionen von kleinen Biotopen und Ökotonen, werden mehrere 3D-Maße (z. B. Maße zur landschaftlichen Vielfalt, zur Fragmentierung bzw. Konnektivität und zum Kontrast) vorgeschlagen. Die vorgeschlagene Methodik wird an zwei realen Beispielen in Deutschland und China angewandt. Die Ergebnisse zeigen zweierlei. Erstens zeigt es sich, dass der integrierte Ansatz der objektbasierten und pixelbasierten Bildverarbeitung effektiv für die Landbedeckungsklassifikation auf unterschiedlichen räumlichen Skalen ist. Die Klassifikationsgüte insgesamt für die Hauptlandbedeckungstypen beträgt 92 % im deutschen und 87 % im chinesischen Testgebiet. Der eigens entwickelte Red Edge-Vegetationsindex (REVI), der sich aus RapidEye-Bilddaten berechnen lässt, erwies sich für die Vegetationsklassifizierung als effizienter verglichen mit dem traditionell verwendeten Normalized Differenced Vegetation Index (NDVI), insbesondere für die Gewinnung der Waldmaske. Im Rahmen der Verwendung von NDSM-Daten erwies sich die dritte Dimension als hilfreich für die Identifizierung von kleinen Biotopen und dem Höhengradienten, beispielsweise an der Wald/Feld-Grenze. Für den Nachweis von Baumreihen und Ökotonen an der Wald/Feld-Grenze wurde der sogenannte pixelbasierte Algorithmus „Pufferung und Schrumpfung“ entwickelt. Im Ergebnis konnten kleine Biotope mit einer Genauigkeit von 80 % und vier verschiedene Ökotontypen im Testgebiet detektiert werden. Zweitens zeigen die Ergebnisse der Anwendung der 3D-Maße in den zwei unterschiedlichen Testgebieten, dass die häufig genutzten Landschaftsstrukturmaße Shannon-Diversität (SHDI) und Simpson-Diversität (SIDI) nicht ausreichend für die Beschreibung der Lebensraumvielfalt sind. Sie quantifizieren lediglich die Zusammensetzung der Lebensräume, ohne Berücksichtigung der räumlichen Verteilung und Anordnung. Eine modifizierte 3D-Version der Effektiven Maschenweite (MESH), welche die Ökotone integriert, führt zu einer realistischen Quantifizierung der Fragmentierung von Lebensräumen. Darüber hinaus wurden zwei höhenbasierte Kontrastindizes, der flächengewichtete Kantenkontrast (AWEC) und der Gesamt-Kantenkontrast Index (TECI), als Ergänzung der Fragmentierungsmaße entwickelt. Sowohl Ökotone als auch Kleinbiotope wurden in den Berechnungen der Kontrastmaße integriert, um deren Randeffekte im Lebensraummuster zu berücksichtigen. Damit kann als ein weiterer Schritt nach der Fragmentierungsanalyse die Randdurchlässigkeit zusätzlich in die Landschaftsstrukturanalyse einbezogen werden. Außerdem wird ein vektorbasierter Algorithmus namens „Multi-Puffer“-Ansatz für die Analyse von ökologischen Netzwerken auf Basis von Landbedeckungskarten vorgeschlagen. Er berücksichtigt Kleinbiotope als Trittsteine, um Verbindungen zwischen Patches herzustellen. Weiterhin werden entsprechende Maße, z. B. die Effective Connected Mesh Size (ECMS), für die Analyse der ökologischen Netzwerke vorgeschlagen. Diese zeigen die Auswirkungen unterschiedlicher angenommener Ausbreitungsdistanzen von Organismen bei der Ableitung von Biotopverbundnetzen in einfacher Weise. Diese Verbindungen zwischen Lebensräumen über Trittsteine hinweg dienen als ökologische Indikatoren für den „gesunden Zustand“ des Systems und zeigen die gegenseitigen Verbindungen zwischen den Lebensräumen. Zusammenfassend kann gesagt werden, dass die Vielfalt der Lebensräume eine wesentliche Ebene der Biodiversität ist. Die Methoden zur Quantifizierung der Lebensraummuster müssen verbessert und angepasst werden, um den Anforderungen an ein Landschaftsmonitoring und die Erhaltung der biologischen Vielfalt gerecht zu werden. Die in dieser Arbeit vorgestellten Ansätze dienen als mögliche methodische Lösung für eine feinteilige Landschaftsstrukturanalyse und fungieren als ein „Trittsteine” auf dem Weg zu weiteren methodischen Entwicklungen für einen tieferen Einblick in die Muster von Lebensräumen

Carbon export from high elevation ecosystems is a critical component of the global carbon cycle. Ecosystems in northern latitudes have become the focus of much research due to their potential as large sinks of carbon in the atmosphere. However, there exists limited understanding of the controls of carbon export from complex mountain catchments due to strong spatial and temporal hydrologic variability, and large heterogeneity in landscape structure. The research presented in this dissertation investigates the control of hydrology and landscape structure and position on two major avenues of carbon loss from mountain watersheds: soil respiration and stream dissolved organic carbon (DOC) export. Measurements of soil respiration and its biophysical controls (soil water content, soil temperature, vegetation, soil organic matter, and soil physical properties) and stream and groundwater DOC dynamics are presented across three years and multiple riparian-hillslope transitions within a complex subalpine catchment in the northern Rocky Mountains, Montana. Variability in soil respiration was related to hydrologic dynamics through space and time and was strongly influenced by topography and landscape structure. Cumulative soil COâ‚‚ efflux was significantly higher from wet riparian landscape positions compared to drier hillslope locations. Changes in hydrologic regimes (e.g. snowmelt and precipitation timing and magnitude) also impacted soil respiration. From a wet to a dry growing season, there were contrasting and disproportionate changes in cumulative growing season surface COâ‚‚ efflux at wet and dry landscape positions. Stream DOC export was also influenced by landscape structure and hydrologic variability. The mobilization and delivery mechanisms of DOC from the soil to the stream were dependent upon the size of DOC source areas and the degree of hydrologic connectivity between the stream and the riparian and hillslope zones, which varied strongly across the landscape. This dissertation provides fundamental insight into the controls of hydrology and landscape structure on carbon export from complex mountain watersheds. The results of this research have large implications for the carbon source/sink status of high elevation mountain ecosystems, the influence of changing hydrologic regimes on soil respiration, and the use of landscape analysis to determine the locations of large source areas for carbon export.

Habitat fragmentation can influence the genetics of a population through the direct loss of genetic diversity, and by the genetic processes that occur as a result of small remnant populations or the geographic isolation of populations. I examined the population genetics of two woodland amphibian species in localities with different land-use histories. The wood frog (Rana sylvatica) and the red-backed salamander (Plethodon cinereus) use the same general habitat but differ with respect to a few key life-history characteristics relating to dispersal. I then compared between species the relative influence each land-use scenario had on the population genetic structure. I found that habitat fragmentation affected the population genetics of the two amphibians and did so differently for each species. The differential population genetic response of these two amphibians to habitat fragmentation reinforces the important role of life-history characteristics in how the genetic structure of a population is shaped over time.

Ecosystem services, the benefits that people receive from ecosystems, depend on the movement of organisms and matter across landscapes, as well as the biodiversity and ecosystem functions that are present. Human activities around the world are rapidly and significantly changing ecosystems, landscapes, biodiversity, and, ultimately, ecosystem services. This is particularly true in agricultural systems, where human activities to maximize the ecosystem service of food production often lead to the decline of other important ecosystem services. While we understand that ecosystem services are critical to human well-being, our current knowledge of the provision of ecosystem services across landscapes contains a number of significant gaps that limit our ability to manage for services and human well-being. In particular, we don't fully understand how changes in landscape structure – the composition and configuration of land use types – affect the provision of multiple ecosystem services.In this thesis, I explore the theoretical and empirical relationships between landscape structure, biodiversity, and ecosystem service provision. I first reviewed our current understanding of these links, finding that while we commonly assume that loss of connectivity between habitat patches in a landscape will have negative effects on ecosystem service provision, we have little empirical evidence that this is the case. In particular, we know little about how this landscape connectivity might simultaneously affect multiple ecosystem services, especially for services other than food, pollination, and pest regulation. I then empirically measured the effects of agricultural landscape structure, including forest fragment connectivity, on six ecosystem services in 34 soybean fields in the Montérégie of southern Québec, Canada. Both the isolation of forest fragments on the landscape, and distances within soybean fields from adjacent forest fragments, had significant effects on the provision of ecosystem services. Importantly, each ecosystem service showed distinct differences in its pattern of provision as these components of landscape structure varied. Therefore, landscape heterogeneity, the variety of forest and field types present in the landscape, was critical to ensure the provision of multiple ecosystem services. Investigating pest regulation in this landscape in more detail, I determined that field width and forest fragments are driving patterns of diversity and abundance for both beneficial and pest arthropods in this system. However, these patterns are contradictory between these two arthropod functional groups, resulting in inconsistent effects of landscape structure on pest regulation. Finally, using a simple modeling framework, I explored how changing the pattern of habitat loss across a landscape affects ecosystem service provision at different scales. My model reveals that the form of the relationship between habitat fragments and ecosystem services is critical in determining landscape patterns of ecosystem service provision. In addition, there are inherent tradeoffs between service provision in the agricultural matrix and habitat preservation, as well as mismatches between ecosystem service provision at different scales. However, altering the amount and pattern of habitat loss across the landscape can help mitigate these issues.Overall, my thesis indicates that understanding the connections between landscape structure, biodiversity, and ecosystem service provision will be a critical avenue of research, one that will improve our ability to design multi-functional human-dominated landscapes. Only by understanding how human activities and land use change affect ecosystem services can we generate management tools to maximize multiple ecosystem services at landscape scales. As human demand for ecosystem services and our impacts on natural systems continue to rise, this will be an increasingly important knowledge gap to fill.
Les services écologiques, les bénéfices que les gens tirent des écosystèmes, dépendent du mouvement des organismes et de la matière à travers le paysage, ainsi que de la biodiversité et des fonctions écosystémiques qui y sont présent. Les activités humaines sont en train de changer rapidement les paysages, la biodiversité et les services écologiques. Ceci est particulièrement vrai dans les systèmes agricoles, où les activités humaines afin de maximiser la production alimentaire conduisent souvent à la diminution d'autres services. Bien que nous comprenions que les services écologiques sont essentiels au bien-être humain, notre connaissance actuelle de la fourniture des services contient encore certaines lacunes qui limitent notre capacité à gérer ces services. En particulier, nous ne comprenons pas entièrement comment les changements dans la structure du paysage affectent la fourniture de multiples services.Dans cette thèse, j'explore les relations entre la structure du paysage, la biodiversité, et l'approvisionnement des services écologiques. J'ai d'abord fait une revue de la littérature pour comprendre nos connaissances actuelles de ces liens, et en constatant que généralement la littérature supporte le fait que la perte de la connectivité dans un paysage aura des effets négatifs sur les services, mais que nous avons peu de preuves empiriques. En particulier, nous savons peu sur la façon dont cette connectivité peut affecter simultanément de multiples services, en particulier pour les services autres que la production de nourriture, la pollinisation, et la régulation des ravageurs. J'ai ensuite mesuré les effets de la structure du paysage agricole, y compris la connectivité des fragments de forêt, sur 6 services écologiques dans 34 champs de soya de la Montérégie au sud du Québec, Canada. L'isolement des fragments, et la distance à partir de fragments adjacents dans les champs ont eu des effets significatifs sur les services. Chaque service a été caractérisé par un motif de provision différent avec les configurations variées de ces deux composantes de la structure du paysage. Par conséquent, l'hétérogénéité du paysage, la variété des types de forêt présents et les types de champs agricoles, sont essentielles pour assurer la fourniture de multiples services. En regardant en plus de détail la régulation des ravageurs, j'ai déterminé que la largeur de champ et la présence des fragments de forêt sont des facteurs déterminants pour la diversité et l'abondance des arthropodes bénéfiques et nuisibles. Cependant, le motif des arthropodes bénéfiques est contradictoires avec celui des arthropodes nuisibles, entraînant des effets de la structure du paysage sur la régulation des ravageurs qui sont inconsistants. Dernièrement, à l'aide d'un cadre de modélisation, j'ai exploré comment changer les motifs de perte d'habitat dans un paysage affecte la fourniture de services écologique à différentes échelles. Mon modèle révèle que la forme de la relation entre les fragments d'habitat et des services est essentielle à la determination de l'approvisionnement de services sur le paysage. De plus, il y a des dissonances entre la prestation de services à différentes échelles. Cependant, la modification du motif de la perte d'habitat peut contribuer à atténuer ces problèmes.Dans l'ensemble, ma thèse indique que la compréhension des liens entre la structure du paysage, la biodiversité, et les services écologiques sera un élément critique de la recherché qui permettra d'améliorer notre capacité à concevoir des paysages multifonctionnels. C'est seulement en comprenant comment les activités humaines et l'utilisation des terres affectent les services écologiques que nous pouvons générer des outils de gestion qui maximise les multiples services à l'échelle du paysage. Comme la demande pour les services écologiques et nos impacts sur les systèmes naturels continuent d'augmenter, ce sera un manque de connaissances de plus en plus important de remplir.

Hantavirus Cardiopulmonary Syndrome (HCPS) is a disease caused by Hantavirus, which are negative-sense RNA viruses in the family Bunyaviridae. These viruses are highly virulent to humans, taking about 50% of infected people to death. The main Hantavirus reservoir is constituded by generalist rodents species, which increase in abundance in agricultural and fragmented landscapes, potencially augmenting the transmission risk of the disease. Climate can also affect rodent population dynamics and the virus survival in the environment, as well as the time it remains virulent, while social factors may regulate the processes of transmitting viruses from reservoirs to humans. However, despite the high virulence of these viruses and the lack of vaccine is not yet well established how these different factors linked to landscape structure, climate and social conditions affect the dynamics of transmission of the disease. Thus, this study aimed to: 1) identify which social and ecological factors affect the transmission of HCPS, identifying the areas of greatest risk in the state of São Paulo and 2) predict how climate change (RCP4.5 and RCP8.5) and expansion of sugarcane scenarios influence the transmission of HCPS. To answer these questions the study system corresponded to the 645 municipalities that compose the state of São Paulo. To achieve our goals, in a first chapter, we conducted a literature review to understand how landscape structure and climate variables affect the risk of HCPS. In a second chapter we used a Bayesian model to quantify the association between HCPS annual incidence in the state of São Paulo, obtained by the number of cases confirmed by the Ministry of Health, between the years 1993-2012, and climate variables (total annual precipitation and mean annual temperature), landscape structure (percentage of native vegetation, number of fragments and percentage of area occupied with sugarcane), chosen in the literature review, and social factors (number of rural men over 14 years - risk population, and the Human Development Index - HDI). We build separate models for the Atlantic Forest and the Cerrado. In both biomes, the risk of HCPS increased mainly with the proportion of land cultivated with sugarcane and the HDI, but the proportion of native habitat, mean annual temperatures and risk population also showed positive relationships to Atlantic Forest. The average risk of HCPS for the state of São Paulo was 1.3%, with 6% of the municipalities being classified as medium to high risk (>= 5%). In a third chapter we used sugarcane expansion and extracted temperature anomalies of RCP4.5 and RCP8.5 scenarios of general circulation models (GCMs) of IPCC5 to predict HCPS risk. With sugarcane expansion, average risk for HCPS increases from 1.3 to 1.5%, while RCP4.5 and RCP8.5 scenarios increased the risk to 1.6% and 1.7%, respectively. RCP4.5 and RCP8.5 scenarios alone are responsible for the largest increase in the maximum risk of infection (46.1% to 51.4% and 51.7%), while the sugarcane expansion combined with climate scenarios are causing the larger expansion in the number of municipalities at high risk, which goes to 7%. Our analyzes provide the first evidence on the action of landscape, climate and social factors in HCPS incidence in the Neotropics. Moreover, our risk maps can be used to optimize the correct allocation of resources, allowing actions to be taken to reduce the impacts of sugarcane expansion and climate change over this disease propagation
A Síndrome Cardiopulmonar por Hantavirose (HCPS) é uma doença causada por Hantavírus, um conjunto de vírus com RNA negativo pertencentes à família Bunyaviridae. Esses vírus são altamente virulentos para os seres humanos, levando cerca de 50% dos infectados a óbito. O principal reservatório de HCPS é constituído por espécies de roedores generalistas, que aumentam em abundância em paisagens agrícolas e fragmentadas, potencialmente elevando o risco de transmissão dessa doença. O clima também pode afetar a dinâmica populacional dos roedores e a sobrevivência do vírus no ambiente, assim como o tempo em que este se mantém virulento, enquanto que fatores sociais podem regular os processos de transmissão dos vírus dos reservatórios para os seres humanos. No entanto, apesar da alta virulência destes vírus e da falta de vacina, não está ainda bem estabelecido como esses diferentes fatores ligados à estrutura da paisagem, ao clima e às condições sociais afetam a dinâmica de transmissão dessa doença. O presente trabalho teve assim como objetivos: 1) identificar quais fatores ecológicos e sociais afetam a transmissão de HCPS, identificando as áreas de maior risco no estado de São Paulo e 2) prever como cenários de mudanças climáticas (RCP4.5 e RCP8.5) e de expansão de cana-de-açúcar influenciam a transmissão de HCPS. Para responder aos nossos objetivos, o sistema de estudo compreendeu os 645 municípios que compõe o estado de São Paulo. Num primeiro capítulo, realizamos uma revisão bibliográfica para entender como as variáveis de paisagem e de clima afetam o risco de HCPS. Num segundo capítulo, utilizamos um modelo Bayesiano para quantificar a associação entre a incidência anual de HCPS no estado de São Paulo, obtida através do número de casos confirmados pelo Ministério da Saúde, entre os anos de 1993 a 2012, e as variáveis de clima (precipitação total anual e temperatura anual média), estrutura da paisagem (porcentagem de vegetação nativa, número de fragmentos e porcentagem de área ocupada com cana-de-açúcar), escolhidas na revisão bibliográfica, além de fatores sociais (número de homens rurais acima de 14 anos - população de risco, e o Índice de Desenvolvimento Humano - IDH). Construimos modelos separados para a Mata Atlântica e o Cerrado. Em ambos os biomas, o risco de HCPS aumentou principalmente com a proporção de terra cultivada com cana-de-açúcar e com o IDH, mas a proporção de habitat nativo, temperatura anual média e população de risco também mostraram relações positivas para Mata Atlântica. O risco médio de HCPS para o estado de São Paulo foi de 1.3%, com 6% dos municípios sendo classificados como de médio a alto risco (>= 5%). Num terceiro capítulo, utilizamos cenários de expansão de cana-de-açúcar e anomalias de temperatura extraidas dos cenários RCP4.5 e RCP8.5 de 32 modelos de circulação geral (GCMs) do IPCC5 para prever os riscos futuros de HCPS. Com a expansão de cana-de-açúcar, o risco médio de HCPS para o estado aumenta de 1.3 para 1.5%, enquanto que os cenários RCP4.5 e RCP8.5 aumentam o risco para 1.6% e 1.7%, respectivamente. RCP4.5 e RCP8.5 sozinhos são os cenários que mais aumentam o risco máximo de infecção (46.1% para 51.4% e 51.7%), enquanto que a expansão de cana-de-açúcar combinada com os cenários climáticos são os que mais provocam o aumento da expansão do risco no estado de São Paulo, expandindo o número de municípios em alto risco para 7%. Nossas análises fornecem as primeiras evidências sobre a ação de fatores da paisagem, climáticos e sociais na incidência de HCPS nos Neotrópicos. Também, nossos mapas de risco podem ser utilizados para otimizar a correta alocação de recursos, permitindo que ações sejam tomadas para reduzir os impactos da expansão da cana e das mudanças climáticas sobre a propagação da doença

Agricultural environments are critical to the conservation of biota throughout the world. This is due both to the limited extent of current reserve systems and the large, and still expanding, proportion of terrestrial environments already dominated by agricultural land-uses. Consequently, there is a growing call from scientists around the world for the need to maximise the conservation value of agricultural environments. Efforts to identify key influences on the conservation status of fauna in agricultural landscapes have taken complementary approaches. Many studies have focussed on the role of remnant or semi-natural vegetation, and emphasised the influence on biota of spatial patterns in the landscape. Others have recognised that many species use diverse ‘countryside’ elements (matrix habitats) within farmland, and emphasise the benefits of landscape heterogeneity for conservation. Here, these research themes have been combined. This study takes a whole-of-landscape approach to investigating how landscape pattern and countryside heterogeneity influence the occurrence of birds in agricultural environments. Birds were sampled in 27 agricultural mosaics, each 1 km x 1 km in size (100 ha), in Gippsland, south-eastern Australia. Mosaics were selected to incorporate variation in two landscape properties: the cover of native vegetation, and richness of different types of element (i.e. land-uses/vegetation types). In each mosaic, 15 fixed sampling locations were stratified among seven different elements in proportion to their cover in the mosaic: native vegetation, linear vegetation, tree plantation, scattered paddock trees, pasture, wetlands and farm dams. Six point counts of birds were undertaken at all sample points in each mosaic: three each in the breeding and non-breeding months of a one-year period (October 2004 – August 2005). Independent measures of the composition, configuration, and heterogeneity of elements in the mosaic had differing effects on the richness of bird species recorded in these same mosaics. Sub-groups of birds based on habitat requirements responded most strongly to the extent of preferred element types in mosaics. Woodland birds (those of greatest conservation concern in farmland environments in Australia) were richer in mosaics with higher cover of native vegetation while open-tolerant species responded to the extent of scattered trees. In contrast, for total species richness, mosaic heterogeneity (richness of element types) and landscape context (cover of native vegetation in surrounding area) had the greatest influence. Mosaic structural properties also influenced the composition of entire bird assemblages in study mosaics. Avifaunal composition showed systematic variation along two main gradients which were readily interpreted in relation to landscape properties: 1) a gradient in the cover of wooded vegetation and, 2) the proportional composition of vegetation types in the mosaic. These gradients represent common trajectories of landscape modification associated with agricultural development: namely, the removal of wooded vegetation and the replacement of native species with exotic vegetation (e.g. crops and plantations). Species possessing different characteristics in relation to three avian life-history traits (nest type, feeding guild and clutch size) varied significantly in their position along these gradients of landscape modification. Species with different nesting requirements showed a strong relationship with the gradient in wooded vegetation cover while species belonging to different feeding guilds were influenced by the gradient defined by the replacement of native vegetation with exotic species. More bird species were recorded in native vegetation than in any other type of element sampled in this study. Nevertheless, most countryside elements had value for many species; particularly structurally complex elements such as scattered trees and tree plantation. Further, each type of landscape element contained different bird assemblages. Species that were recorded in a greater number of different types of landscape element were also recorded in more mosaics. This was true for all species and for woodland birds, and indicates that species that can use a greater range of countryside elements may have an increased tolerance of future landscape modification. The richness of woodland species at survey sites in different elements was influenced by features of the mosaic in which they occurred. Notably, the richness of woodland bird species recorded at sites in scattered trees and pasture increased with a greater cover of native vegetation in the overall mosaic. Of the overall pool of woodland bird species documented in the broader study region, 35% of species were not recorded in the agricultural mosaics sampled here. While many of these species were uncommon in the study area, or were associated with vegetation communities infrequently sampled in mosaics, this shows that conservation efforts in agricultural landscapes will not be appropriate for all species. For those woodland species that were recorded, measures of the extent of wooded vegetation cover had a strong, positive influence on the frequency of occurrence of individual species in mosaics. Thus, individual species of woodland bird occurred more frequently in mosaics with a greater cover of wooded vegetation. Nine woodland species showed a stronger response to measures of vegetation cover that included tree plantation and/or scattered trees than to the cover of native vegetation alone. For these species, structurally complex countryside elements provide valuable supplementary habitat at the landscape scale. Results of this study show that landscape properties influence the occurrence of birds in agricultural mosaics. The extent of cover of element types, particularly native vegetation, had the strongest influence on all measures of bird occurrence in mosaics. Thus, native vegetation is vital for the persistence of birds in farmland landscapes and is the primary element on which conservation efforts in these environments depend. Nevertheless, with careful management, countryside elements may provide additional conservation benefits for many bird species. Countryside elements made an important contribution to landscape heterogeneity, the landscape property with greatest influence on overall bird richness in mosaics. Countryside elements also increased the structural complexity of cleared agricultural land, and so have the capacity to enhance connectivity in fragmented landscapes. A focus on these factors (landscape heterogeneity and structural complexity) will provide the greatest opportunities for using countryside elements to increase the conservation value of farmland environments for native fauna. The relatively small scale of this study indicates that the cumulative effect of even small elements in farm mosaics contributes to the structural properties of entire landscapes. Critically, this emphasises the important contribution that individual landholders can make to nature conservation in agricultural environments.

This research is an investigation into the phrase 'intermediate landscape' and tests this concept in the re-development of the Sanya waterfront, China. The phrase is based on the 'missing link' in the current disconnection between the landscape and urban development in Sanya city. If the landscape is considered as a connection across scales and urban systems rather than an isolated system, then how can landscape affect the structure and function of urban development? The 'intermediate landscape' considers the impact of understanding landscape not as an additional layer, but as a structure that can connect the urban context at different scales while at the same time addressing its function. This project attempts to formulate strategies of 'intermediate landscape' to coordinate the transformation of developing cities.

An ecological approach to land-use planning is essential to maintain the long-term sustainability of ecosystem benefits, services, and resources. Concern about environmental quality and the long-term livability of urban areas is now a driving force in urban planning and design. The interrelated issues of growth management, smart growth, sustainable development, and new urbanism are topics in the most vibrant discussions at all levels of planning and landscape architecture. Within this context, this study starts from the interest in the ecological planning and management in urban areas, especially related to the issue of local development regulation and guidelines. Landscape regulations have come into existence recently in communities across the nation and these regulations vary from one region to another and from one community to another. The aims of this study were to investigate the relationship between ecological landscape structure and local development regulations over time. Comparison analysis was conducted between two areas that had similar pre-development ecological conditions but were developed under vastly different regulatory environments. The Woodlands (regulated to protect ecological condition) and the North Houston area (which followed traditional subdivision regulations) were examined at three different developmental time periods: predevelopment, early development (after 10 years), and matured development (after 30 years). Aerial photos of each site from the three time periods were classified into forested and non-forested classes and the landscape structure was quantified with a number of landscape metrics related to fragmentation??an indicator of habitat degradation. Two factors, the ecological approach to landscape planning and the adoption of more restrictive landscape regulations and guidelines, are discussed on the premise that they exert influence in developing and maintaining the long-term sustainability of ecosystems. In conclusion, this study provides the quantified landscape configuration and composition of the effects of development regulations on landscape structure. The ecologically planned community shows a less fragmented forest pattern and more restrictive development guidelines result in more ecologically structured environments. Understanding how elements of local development regulations affect ecological landscape patterns is important for landscape architects, planners, and administrators because it can lead to better strategies for planning and designing sustainable communities.

Visual Topology is used here to describe the spatial relations between objects as they appear in the 2D viewing plane. This thesis sets out the concept, explains why it is needed in Geographic Information Science and suggests how it may be computed through development of prototype software. Section 1 considers the functionality that any Spatial Data Infrastructure would need to encompass in order to support the inclusion of visual analysis into landscape planning and monitoring systems. Section 2 introduces various aspects of visual topology. In particular it sets out how visual intersections of occluding edges may be modelled topologically and formally defines a novel higher level topological structure to the viewing space - the 'Euler Zone' based on the Euler complexity of a graph formed by the occluding horizons in a view. Whether such a graph has meaning to an observer is considered in Section 5, which presents the results of a web based forced­ choice experiment with significant implications for the role of topology in modelling landscape preference via quantitative metrics derived from 20 maps. Sections 3 and 4 discuss how existing methods for handling perspective models and visualisations need to be improved in order to model visual topology. Section 3 focuses on the limitations of current techniques and design criterion for a new methodology. Section 4 looks at the lessons learnt from developing a prototype implementation (VM-LITE) based on Quad-Edge Delaunay Triangulation, in the VoronoiMagic software package. Some potential applications are highlighted, both within landscape modelling and beyond, before drawing conclusions as to the potential for the concepts and methods respectively. Although important research questions remain, particularly as regards view point dynamics, Visual Topology has the potential to fundamentally change how visual modelling is undertaken in GIS. It allows the analysis of scenes based upon a richer representation of individual experience. It provides the basis for data structures that can support the extraction of generalisable metrics from this rich scene information, taking into account the qualitatively different nature of scene topology as distinct from metrics of shape and colour. In addition new metrics based on attributes only apparent in perspective, such as landform, can be analysed. Finally, it also provides a rationale for reporting units for landscapes with some measure of homogeneity and scale-independence in their scenic properties.

The objective of the current study was to analyse the effect of landscape structure (habitat size and exposure to farmland) on the occurrence and abundance of Lobaria pulmonaria, a foliose cyanolichen. Since the agrarian revolution during the 19th century the agricultural landscape has become increasingly fragmented resulting in isolated meadows and wood-pastures surrounded by farmland. Lobaria pulmonaria is one of the species being affected by this habitat change, much due to their dispersal limitations, specific habitat demands and susceptibility to air pollution. 36 localities of two different size classes (< 1.5 ha and > 4.5 ha) and two different exposure classes (exposed or unexposed to farmland) were studied. The occurrence, size of lichen thallus and height of lichen patches on tree trunks were significantly positively affected by habitat size and negatively affected by habitat exposure. The implications of these findings for strategies to manage and conserve L. pulmonaria in a fragmented landscape are discussed.

Recent work in microbial ecology has focused on elucidating controls over biogeographic patterns and connecting microbial community composition to ecosystem function. My objective was to investigate the relative influences of landscape legacies and contemporary environmental factors on the distribution of soil microbial communities and their contribution to ecosystem processes across a glacial till sequence in Taylor Valley, Antarctica. Within each till unit, I sampled from dry areas and areas with visible evidence of recent surface water movement generated by seasonal melting of ephemeral snow packs and hillslope ground ice. Using T-RFLP 16S rRNA gene profiles of microbial communities, I analyzed the contribution of till and environmental factors to community similarity, and assessed the functional potential of the microbial community using extracellular enzyme activity assays. Microbial communities were influenced by geochemical differences among both tills and local environments, but especially organized by variables associated with water availability as the first axis of an NMDS ordination was strongly related to shifts in soil moisture content. CCA revealed that tills explained only 3.4% of the variability in community similarity among sites, while geochemical variables explained 18.5%. Extracellular enzyme activity was correlated with relevant geochemical variables reflecting the influence of nutrient limitation on microbial activity. In addition, enzyme activity was related to changes in community similarity, particularly in wet environments with a partial Mantel correlation of 0.32. These results demonstrate how landscape history and environmental conditions can shape the functional potential of a microbial community mediated through shifts in microbial community composition.
Master of Science

Climate and human activities impact the timing and quantity of streamflow and floods in different ways, with important implications for people and aquatic environments. Impacts of landscape changes on streamflow and floods are known, but few studies have explored the magnitude, duration and count of floods the landscape can influence. Understanding how floods are influenced by landscape structure provides insight into how, why and where floods have changed over time, and facilitates mapping the capacity of watersheds to regulate floods. In this study, I (1) compared nine flood-return periods of 31 watersheds across North Carolina and Virginia using long-term hydrologic records, (2) examined temporal trends in precipitation, stream flashiness, and the count, magnitude and duration of small and large floods for the same watersheds, and (3) developed a methodology to map the biophysical and technological capacity of eight urban watersheds to regulate floods. I found (1) floods with return periods ≤ 10 years can be managed by manipulating landscape structure, (2) precipitation and floods have decreased in the study watersheds while stream flashiness has increased between 1991 and 2013, (3) mapping both the biophysical and technological features of the landscape improved previous efforts of representing an urban landscape's capacity to regulate floods. My results can inform researchers and managers on the effect of anthropogenic change and management responses on floods, the efficacy of current strategies and policies to manage water resources, and the spatial distribution of a watershed's capacity to regulate flooding at a high spatial resolution.
Master of Science

A case study at a global pharmaceutical company has been conducted toanalyse how the Hidden Structure method using the Enterprise Architecture Analyses(EAAT) tool, developed at KTH, can be used to visualize the IT architecture and tocreate a better understanding on which applications could increase a risk of therobustness of the architecture if changes was done to them. Also the measure of ITsupport metrics as incidents and changes per system has been analysed to understandif they can be used to understand the robustness of the incident. The tool was used tocreate a model of the enterprise architecture of the company and the analysis showedthat the robustness of the IT architecture was good; the core applications that couldcreate most damage were identified. The analysis of the IT support metrics showedthat it was difficult to use the change records as indicators since the number ofchanges per systems were very few. The incident analysis showed that the systemswith the highest number of incidents were classified as belonging core or peripheralcategory.

Riparian ecosystems are disproportionately biodiverse and vital to many taxa despite their scant footprint on the landscape. Yet globally they are also under the greatest human-caused threats. The loss of habitat is the greatest driver of species declines, but fragmentation may also significantly impact populations by creating barriers to dispersal. Effective conservation requires an informed understanding of species' threats and capabilities, though it is unclear whether the increasing fragmentation of riparian woodland in western North America is affecting dispersal patterns of riparian breeding birds. Research suggests long distance migrants may be less impacted than resident species, though previous genetic research on the threatened western population of the yellow-billed cuckoo (Coccyzus americanus), a long-distance Neotropical migrant and obligate riparian breeding bird, suggests local structuring among isolated western populations. There is also interest in using more informative markers to assess genetic differentiation between eastern and western yellow-billed cuckoos. Despite limited differentiation found in mitochondrial sequences between eastern and western cuckoos, analysis of microsatellite markers is expected to reveal significant population structuring. Comparing 14 polymorphic microsatellite loci among seven separate populations in the west, and between western and eastern samples, I found limited population structuring, suggesting sufficient dispersal is occurring to maintain gene flow, both among isolated western, and between western and eastern populations. I found lower than expected heterozygosity across the range, possibly due in part to higher rates of inbreeding experienced by small populations, though the results were clouded by a high number of estimated null alleles downward-biasing estimates of heterozygosity. To test the accuracy of the microsatellites and measure scoring error, I compared microsatellites and mitochondrial sequences in nesting groups sampled from high-density restoration sites on the lower Colorado River. To identify the nesting males and females, I modified a universal avian sexing protocol, optimizing it for yellow-billed cuckoos. I calculated a scoring error rate of 2.12%, 0.91% not explained by null alleles. I also confirmed a relatively high rate of conspecific nest parasitism, with the nesting male apparently fathering the parasitic young in many cases. This is the first assessment of the relationships among breeding adults and nestlings of this species. With more nests providing more egg-dumping opportunities, the productivity of parasitic females should increase with larger populations of nesting cuckoos. Restoring more large patches of functional riparian woodland, to support multiple nesting pairs, could help to recover this declining population.

Small peptides work as neurotransmitters or hormones in the body. For example, the pentapeptide enkephalin is involved in a wide variety of physiological processes such as mediation of pain and respiratory depression. In order to understand the biological function of these molecules it is necessary to examine their molecular shape and structural preferences. The large flexibility of peptides makes them difficult to be characterized by experimental and theoretical methods. A method was developed in order to explore the conformational preferences of a polypeptide using electronic structure methods based on hierarchical selection criteria. The strategy was to vary all the torsion angles of the peptide and to create all possible conformers. The conformers were assessed according to the number of hydrogen-bonding interactions in their structure. Calculations were performed at increasingly higher levels of theory. Only a number of the most stable conformers were taken through to the next level. This hierarchical selection method was used to explore the conformational features of the dipeptide Tyr-Gly (the first two amino acids of the pentapeptide enkephalin: Tyr-Gly-Gly-Phe-Met).The conformational preferences of Tyr-Gly were also explored with a stepwise rotation method. The hierarchical selection method seemed to be superior. The most stable conformers found for Tyr-Gly are characterized by a characteristic hydrogen-bonding interaction (0-H 0) between the hydroxyl hydrogen of glycine and the carboxyl oxygen of tyrosine. The optimized structures obtained with DFT differ from the structures obtained by MP2 geometry optimizations. MP2 optimizations make the structures more folded. The method has also been used to study the conformational features of the Tyr- Gly-Gly tripeptide, Tyr-Gly-Gly-Phe tetrapeptide, Tyr-Gly-Gly-Phe-Leu pentapeptide and Gly-GIy-Gly tripeptide. The most stable conformers obtained for the Tyr-Gly-Gly tripeptide are characterized by folded structures with a characteristic hydrogen-bonding interaction between the (-OH) phenyl group of tyrosine and the carboxyl oxygen of glycine (3). The most stable conformers obtained for Tyr-Gly-Gly-Phe and Tyr-Gly-Gly-Phe-Leu are characterized by folded structures with a characteristic hydrogen-bonding interaction between the (-OH) phenyl group of tyrosine and the carboxyl oxygen of phenylalanine (4). For Tyr-Gly, Tyr-Gly-Gly, Tyr-Gly-Gly-Phe and Tyr-Gly-Gly-Phe-Leu a large variation has been observed between DFT and MP2 orders of stability of the conformers. DFT fails to describe the dispersion effects arising from interactions involving the aromatic residues. MP2 would probably describe more accurately the conformational preferences of these peptides. However, the large basis set superposition error in MP2 calculations means that also MP2 may not be suitable to characterize the conformational preferences of these peptides. The hierarchical selection method developed has been shown to be a useful method to study small peptides.

Climate change may produce a variety of responses in populations' ecological and evolutionary dynamics. At opposing limits of populations' ranges, the responses are expected to differ. Some lag in response may be expected due to the rapidity of climate change, with the strength and type of lags varying across space. Importantly responses may contain both ecological and evolutionary components. This thesis provides significant contribution to understanding how structure in populations and the landscape may determine the nature of populations' responses to climate and environmental changes. A number of models and a microcosm experiment are presented. The results show how alternate temporal and spatial population structures are developed when individuals move in space. From defining percolation routes, patterns of gene flow or spatial selection, landscapes provide a large role in determining populations' responses. Even without landscape structure, populations exhibit large levels of regional structure, and indeed substructure, due to localised interactions. This spatial structure may deform during climate change, producing new characteristics of equilibrium spatial distributions. During range deformation the feedback between spatial structure and dynamics can alter populations' evolvability by changing the patterns and strength of intraspecific competition, or the maintenance of genetic variation. These changes produce dynamics that will be sensitive to individual differences in a population. Changes in populations' age and sex structure may modulate ecological and evolutionary interactions. The research presented here highlights an increased importance of understanding populations' spatio-temporal structure and dynamics within heterogeneous landscapes. This is especially so as ecological and evolutionary processes can converge to different degrees during climate change, depending on the landscape a population inhabits. Prediction of populations' responses may require a greater understanding of spatial processes and how range deformation affects the evolution of different kinds of traits. All the above areas feed into a greater understanding of the genesis and maintenance of diversity in any situation.

Classification procedures, including atmospheric correction satellite images as well as classification performance utilizing calibration and validation at different levels, have been investigated in the context of a coarse land-cover classification scheme for the Pachitea Basin. Two different correction methods were tested against no correction in terms of reflectance correction towards a common response for pseudo-invariant features (PIF). The accuracy of classifications derived from each of the three methods was then assessed in a discriminant analysis using crossvalidation at pixel, polygon, region, and image levels. Results indicate that only regression adjusted images using PIFs show no significant difference between images in any of the bands. A comparison of classifications at different levels suggests though that at pixel, polygon, and region levels the accuracy of the classifications do not significantly differ between corrected and uncorrected images. Spatial patterns of land-cover were analyzed in terms of colonization history, infrastructure, suitability of the land, and landownership. The actual use of the land is driven mainly by the ability to access the land and markets as is obvious in the distribution of land cover as a function of distance to rivers and roads. When considering all rivers and roads a threshold distance at which disproportional agro-pastoral land cover switches from over represented to under represented is at about 1km. Best land use suggestions seem not to affect the choice of land use. Differences in abundance of land cover between watersheds are more prevailing than differences between colonist and indigenous groups.

Floodplain forests and landscape-level processes and dynamics have been largely neglected throughout the Amazon basin. Additionally, relatively little ecological and conservation research has been carried out in the Purus river basin since William Chandless' pioneering geographic exploration nearly 140 years ago. This thesis presents results from a large-scale natural forest mosaic including upland terra firme forest and floodplain forests (varzea and igap6) in the lower Purus region of central Brazilian Amazonia. Floristic composition and vertebrate assemblages across different forest types were investigated using floristic plots and line-transect censuses, respectively. The tree and vertebrate assemblages were consistently more species-poor in seasonally flooded forests compared to those of terra firme forests. A low similarity between tree assemblages at different plots was found, which reinforces the notion that closed-canopy Amazonian forest landscapes are not homogenous even at relatively small spatial scales. The impoverished mammal fauna in flooded forest environments both in terms of primates and other non-volant mammals appear to partly reflect the combined effects of forest structure and connectivity, habitat heterogeneity and floristic diversity. Phenological patterns of the tree assemblages in terra firme, v3.rzea and igap6 forest were examined by direct crown inspections of plant parts. Vegetative and reproductive phenophases were highly seasonal in all forests types. These patterns were strongly linked to environmental variables such as rainfall and the seasonal flood pulse. Vertebrate detection rates varied over time for all species both within and between each forest type, the latter suggesting that many species use flooded forests on a seasonal basis. The fluctuations in some species were significantly correlated with the abundance of fruits. The highly heterogeneous landscape consisting of terra firme, vmea and igap6 forest increased the regional ~-diversity and appeared to play an important role in the dynamics and year-round survival of many vertebrate species. This is of great conservation concern as a meagre 3.3% of flooded forests presently occur within strictly protected areas in the Brazilian Amazon.

A high proportion of amphibian species are threatened with extinction globally, and habitat loss and degradation are the most frequently implicated causes. Rapid deforestation for the establishment of agricultural production is a primary driver of habitat loss in tropical zones where amphibian diversity is highest. Land-cover change affects native assemblages, in part, through the reduction of habitat area and the reduction of movement among remnant populations. Decreased gene flow contributes to loss of genetic diversity, which limits the ability of local populations to respond to further environmental changes. The focus of this dissertation is on the degree to which common land uses in Sarapiquí, Costa Rica impede the movement of two common amphibian species. First, I used field experiments, including displacement trials, and a behavioral landscape ecology framework to investigate the resistance of pastures to movement of Oophaga pumilio. Results from experiments demonstrate that pastures do impede movement of O. pumilio relative to forest. Microclimatic effects on movement performance as well as limited perceptual ranges likely contribute to reduced return rates through pastures. Next, I linked local processes to landscape scale estimates of resistance. I conducted experiments to measure habitat-specific costs to movement for O. pumilio and Craugastor bransfodrii, and then used experimental results to parameterize connectivity models. Model validation indicated highest support for resistance estimates generated from responses to land-use specific microclimates for both species and to predator encounters for O. pumilio. Finally, I used abundance and experiment-derived resistance estimates to analyze the effects of prevalent land uses on population genetic structure of the two focal species. While O. pumilio did not exhibit a strong response to landscape heterogeneity and was primarily structured by distances among sites, C. bransfordii genetic variation was explained by resistance estimates from abundance and experiment data. Collectivity, this work demonstrates that common land uses can offer different levels of resistance to amphibian movements in Sarapiquí and illustrates the value of investigating local scales processes to inform interpretation of landscape-scale patterns.

Establishing metrics of diversification can calibrate the observed scope of diversity within a lineage and the potential for further phenotypic diversification. There are two potential ways to calibrate differences between phenotypes. The first metric is based on the structure of the network of direct and indirect connections between elements, such as the genes, proteins, enzymes and metabolites that underlie a phenotype. The second metric characterizes the dynamic properties that determine the strength of the interactions among elements, and influence which elements are the most likely to interact. Determining how the connectivity and strength of interactions between elements lead to specific phenotypic variations provides insight into the tempo and mode of observed evolutionary changes. In this dissertation, I proposed and tested hypotheses for how the structure and metabolic flux of a biochemical network delineate patterns of phenotypic variation. I first examined the role of structural properties in shaping observed patterns of carotenoid diversification in avian plumage. I found that the diversification of species-specific carotenoid networks was predictable from the connectivity of the underlying metabolic network. The compounds with the most enzymatic reactions, that were part of the greatest number of distinct pathways, were more conserved across species’ networks than compounds associated with the fewest enzymatic reactions. These results established that compounds with the greatest connectivity act as hotspots for the diversification of pathways between species. Next, I investigated how dynamic properties of biochemical networks influence patterns of phenotypic variation in the concentration and occurrence of compounds. Specifically, I examined if the rate of compound production, known as metabolic flux, is coordinated among compounds in relation to their structural properties. I developed predictions for how different distributions of flux could cause distinct diversification patterns in the concentrations and presence of compounds in a biochemical network. I then tested the effect of metabolic network structure on the concentrations of carotenoids in the plumage of male house finches (Haemorhous mexicanus) from the same population. I assessed whether the structure of a network corresponds to a specific distribution of flux among compounds, or if flux is independent of network structure. I found that flux coevolves with network structure; concentrations of metabolically derived compounds depended on the number of reactions per compound. There were strong correlations between compound concentrations within a network structure, and the strengths of these correlations varied among structures. These findings suggest that changes in network structure, and not independent changes in flux, influence local adaptations in the concentrations of compounds. Lastly, the influence of carotenoid network structure in the evolutionary diversification of compounds across species of birds depends on how the structure of the network itself evolves. To test whether the carotenoid metabolic network structure evolves in birds, I examined the patterns of carotenoid co-occurrence across ancestral and extant species. I found that the same groups of compounds are always gained or lost together even as lineages diverge further from each other. These findings establish that the diversification of carotenoids in birds is constrained by the structure of an ancestral network, and does not evolve independently within a lineage. Taken together, the results of this dissertation establish that local adaptations and the evolutionary diversification of carotenoid metabolism are qualitatively predictable from the structure of an ancestral enzymatic network, and this suggests there is significant structural determinism in phenotypic evolution.

Abstract I studied the ecology of the goshawk-grouse relationship in Oulu, northern Finland, during and outside the breeding season, by radio-telemetry. This included museum samples of goshawk to obtain a better ecological as well as a better evolutionary understanding of it. The proportion of grouse in the diet of goshawks has decreased since the 1960's, in accordance with the decline of grouse populations. The main prey groups replacing the lacking grouse were corvids, squirrels and hares. The proportion of grouse was highest in spring and it decreased towards the end of the nestling phase. The most preferred grouse species were hazel grouse Bonasa bonasia and willow grouse Lagopus lagopus. Preferences for different prey types are not explained by active choices of goshawk, but by changes in the vulnerability of the prey species. The nestling phase, when food demand is highest, is not adjusted to when prey supply is highest, but before it. The size and shape of the goshawks has changed from the 1960's. Adult males became smaller but females larger. Both became relatively longer winged and tailed. Decrease of male's size may be a response to the change in the food supply. Prey types replacing grouse are generally smaller, which may cause the change in the male's morphology. Females being less active during the breeding season may not be affected. For the female to be larger is advantageous in winter when they kill 'over large' prey like mountain hares Lepus timidus and capercaillie cocks Tetrao urogallus. Wintering goshawks were mainly females in adult plumage that tended to stay in the study area. However, only one third bred locally. More than one quarter of all hawks died during the study. Although known to be inhabitants of old forests, which this study supports, goshawks are fairly well adapted to mosaic landscape resulting from modern forestry, providing that suitable sized prey is available. Females have less problems, probably because hares, the main winter prey for females, are not affected negatively by forestry, like grouse and squirrels are, the main prey for males. Goshawks have a remarkable impact on grouse populations, especially when non-territorial hawks, 'floaters' are also included. About one half of the total mortality rate of grouse may be due to goshawk predation. Goshawk predation accords to predictions of general predation theory and may be a noticeable factor contributing to cyclicity in grouse.

At regional scales climate patterns (e.g., interannual wet-dry cycles) result in high spatial fire synchrony among Southwest forests. However, in the "Sky Island" forests of southeastern Arizona spatial and temporal patterns of fire history and tree age structure at landscape levels (i.e., within mountain ranges) are relatively unknown and therefore the focus of this study. In the Santa Catalina Mountains we reconstructed the fire history on a 2,900-hectare study area with two distinct landscapes, Butterfly Peak (BP) and Rose Canyon (RC) using 2-hectare "points" (i.e., collection areas). The RC landscape was dominated by shallow south-facing aspects and BP was dominated by steep north-facing aspects. Within each landscape, point mean fire intervals (PMFIs) were not significantly different between aspect classes. However, pooled PMFIs were significantly shorter in RC compared to BP. These results show that the fire history at any given point (i.e., 2 hectares or less) was primarily controlled by the broad-scale topography of the encompassing landscape, rather than by the fine-scale topography at that point.Using similar methods we also reconstructed the fire history on Rincon Peak, which is a small isolated mountain range with very step topography. The fire history of the 310-hectare forest area was a mixture of frequent low severity surface fires (from AD 1648 to 1763) and infrequent mixed-severity fires (from AD 1763 to 1867). This mixed-fire regime was probably due to a combination of climatic variability, the small area and rugged topography of this mountain range, and complex fuel arrangements. The distinct fire histories from these two study areas provided natural age structure experiments that indicated tree age cohorts (i.e., higher than expected tree establishment pulses) occurred during periods of reduced fire frequencies. In some instances these periods were likely caused by climatic variability (e.g., a wet and/or cool early 1800s) creating synchronous age cohorts across the region. At other times, extended fire intervals were a function of local topography (e.g., 1763-1819 in the northern half of Rincon Peak). Overall, these studies demonstrated that landscape and climatic variations combine to produce complex spatial and temporal variations in fire history and tree age structures.