The opening of large archives of satellite data such as LANDSAT, MODIS and the SENTINELs has given researchers unprecedented access to data, allowing them to better quantify and understand local and global land change. The need to analyze such large data sets has led to the development of automated and semi-automated methods for satellite image time series analysis. However, few of the proposed methods for remote sensing time series analysis are available as open source software. In this paper we present the R package dtwSat. This package provides an implementation of the time-weighted dynamic time warping method for land cover mapping using sequence of multi-band satellite images. Methods based on dynamic time warping are flexible to handle irregular sampling and out-of-phase time series, and they have achieved significant results in time series analysis. Package dtwSat is available from the Comprehensive R Archive Network (CRAN) and contributes to making methods for satellite time series analysis available to a larger audience. The package supports the full cycle of land cover classification using image time series, ranging from selecting temporal patterns to visualizing and assessing the results.

The human-induced changes of the Earth's land surfaces have been unprecedented, with outcomes often indicating degradation and loss of environmental quality. Mato Grosso State in Brazil, location of the study area, underwent extensive land-use and land-cover changes in recent decades with the rates, patterns and consequences poorly documented until now. In this context, the aim of the present research is to propose a multidisciplinary approach for quantifying historical land-use and environmental changes in the southeast part of this State, where the Cerrado biome (Brazilian savannas) has been intensively converted into agricultural lands. The methodology includes three parts: remote sensing change detection, land vulnerability mapping, and identification of key environmental indicators. Land-use/cover information was extracted from a temporal remote sensing dataset using an object-oriented classification approach, and the changes quantified employing a post-classification method. In addition, the study area was assessed for its vulnerabilities, focusing mainly on erosion risks, wetlands, and areas with limited or no suitability for crops. Finally, key environmental indicators were identified from the preceding steps and analyzed within the Organisation for Economic Co-operation and Development (OECD) Pressure-State-Response (PSR) framework. The results provided an improved mapping of the Cerrados natural vegetation conversion into crops and pastures, and indicate that the Cerrado vegetation was intensively converted and also became more fragmented in the time frame studied. Between 1985 and 2005 the area lost approximately 6491 km 2 of Cerrados (42 %). Modeling based on the Universal Soil Loss Equation indicated significant increase in erosion risk from 1985 to 2005 mainly related to the increase in crop areas and the crops' encroachment into more fragile lands.The identification of environmental indicators rendered complex environmental information more generally accessible by structuring it within the PSR framework.The indicators captured key information about land-use and environmental changes in the area, showing that agricultural expansion is the major human activity exerting pressure on natural resources at a landscape scale, and that the pattern of change included high rates of crop expansion and the use of fragile environments such as wetlands and sandy erodable soils.

Entender como o balanço hídrico de uma bacia hidrográfica é afetado pela conversão de florestas em cultivos agrícolas e pastagens permite avaliar os possíveis impactos da mudança de uso e cobertura do solo na sustentabilidade regional. Com o modelo hidrológico de grande escala VIC (Variable Infiltration Capacity) calibrado para as condições locais simulou-se os possíveis efeitos em três cenários de substituição da cobertura vegetal na bacia do rio Ji-Paraná, Rondônia. Um cenário imagina a substituição total da floresta pela cultura da soja, e nessas condições a vazão do rio aumentou em 28% durante o período chuvoso, e em até 70% na época seca, quando comparados às vazões atuais. Quando a substituição foi por pastagens esse aumento foi um pouco menor, 11% no período chuvoso e 16% no período seco. Esses dois cenários mutuamente exclusivos foram selecionados por representar condições extremas de uso do solo. Um terceiro cenário simulou a possível condição original da bacia coberta totalmente pela floresta. Esse último cenário permite inferir sobre as possíveis conseqüências das mudanças já ocorridas visto que as medidas de vazão são recentes (menos de 30 anos). Nessa condição a vazão sofreu redução de 9% durante o período chuvoso e de 20% no período seco. O modelo indicou ainda redução de 30% na evapotranspiração dessas culturas, durante o período seco, quando comparado ao cenário de floresta. / The understanding of how the water balance of a hydrographic basin is affected by the conversion of forests into crops and pasture allow to evaluate the possible impacts of the land use and land cover changes in the regional sustainability. Using a macro-scale hydrologic VIC (Variable Infiltration Capacity) model calibrated for local conditions we simulated the possible effects on the hydrology under three scenarios of land cover substitution of the Ji-Paraná basin, state of Rondônia (western region of Brazil). One scenario simulated the total replacement of forest by soybeans crops, under this condition the outflow of the river increased in 28% during the rainy period, and up to 70% at the dry period, when comparative to the current outflows. When forest was replaced by pastures, this increase was a little lower, 11% in rainy season and 16% in the dry period. These two exclusive scenarios have been selected by representing extreme conditions of land use. One third scenario simulated the possible original condition of the basin covered by forest. This last scenario allows to infer on the possible consequences of the actual changes since recent measures of outflow (less than 30 years). In this condition the outflow suffered a reduction of 9% during the rainy period and 20% in the dry period. The model indicated a decrease of 30% in evapotranspiration for these crops in dry period compared to the forest scenario.

Entender como o balanço hídrico de uma bacia hidrográfica é afetado pela conversão de florestas em cultivos agrícolas e pastagens permite avaliar os possíveis impactos da mudança de uso e cobertura do solo na sustentabilidade regional. Com o modelo hidrológico de grande escala VIC (Variable Infiltration Capacity) calibrado para as condições locais simulou-se os possíveis efeitos em três cenários de substituição da cobertura vegetal na bacia do rio Ji-Paraná, Rondônia. Um cenário imagina a substituição total da floresta pela cultura da soja, e nessas condições a vazão do rio aumentou em 28% durante o período chuvoso, e em até 70% na época seca, quando comparados às vazões atuais. Quando a substituição foi por pastagens esse aumento foi um pouco menor, 11% no período chuvoso e 16% no período seco. Esses dois cenários mutuamente exclusivos foram selecionados por representar condições extremas de uso do solo. Um terceiro cenário simulou a possível condição original da bacia coberta totalmente pela floresta. Esse último cenário permite inferir sobre as possíveis conseqüências das mudanças já ocorridas visto que as medidas de vazão são recentes (menos de 30 anos). Nessa condição a vazão sofreu redução de 9% durante o período chuvoso e de 20% no período seco. O modelo indicou ainda redução de 30% na evapotranspiração dessas culturas, durante o período seco, quando comparado ao cenário de floresta. / The understanding of how the water balance of a hydrographic basin is affected by the conversion of forests into crops and pasture allow to evaluate the possible impacts of the land use and land cover changes in the regional sustainability. Using a macro-scale hydrologic VIC (Variable Infiltration Capacity) model calibrated for local conditions we simulated the possible effects on the hydrology under three scenarios of land cover substitution of the Ji-Paraná basin, state of Rondônia (western region of Brazil). One scenario simulated the total replacement of forest by soybeans crops, under this condition the outflow of the river increased in 28% during the rainy period, and up to 70% at the dry period, when comparative to the current outflows. When forest was replaced by pastures, this increase was a little lower, 11% in rainy season and 16% in the dry period. These two exclusive scenarios have been selected by representing extreme conditions of land use. One third scenario simulated the possible original condition of the basin covered by forest. This last scenario allows to infer on the possible consequences of the actual changes since recent measures of outflow (less than 30 years). In this condition the outflow suffered a reduction of 9% during the rainy period and 20% in the dry period. The model indicated a decrease of 30% in evapotranspiration for these crops in dry period compared to the forest scenario.

This thesis deals with the evaluation of land cover changes in twelve cadastral areas in the central part of the Bohemian Forest. This area was gradually abandoned due to political changes in the 20th century. For the purpose of this study, the historical Stabile Cadastre maps from 1837 and aerial photographs from 1949 and 2008 are used. The work follows both the development of the area as a whole and the development of the individual segments around the "Iron Curtain ", built after the World War II. Another aim of this work is to determine the spatial distribution of trees in an open countryside. Field data are supplemented with the features calculated from the digital elevation model and the distances of each species to man-made landscape elements present in the area around the time of displacement (aerial photos from 1949).

Le paysage constitue à la fois un cadre de vie pour les populations humaines et un support du cycle de vie des espèces animales. Les modifications du paysage induites par les dynamiques d’occupation du sol se répercutent sur ces deux dimensions, l’une esthétique et l’autre écologique. Ces logiques étant généralement étudiées dans des champs disciplinaires différents, peu de recherches ont porté sur la manière dont elles s’articulent selon les modifications des structures paysagères.Ce travail cherche donc à modéliser de manière rétrospective la coévolution spatiale des fonctions esthétique et écologique du paysage à partir de métriques spatiales basées sur des données d’occupation du sol. Il se focalise sur les changements intervenus dans les franges urbaines de deux agglomérations françaises (Besançon et Paris) durant les 30 dernières années.La démarche adoptée a d’abord visé à modéliser, à partir des données d’occupation du sol, (1)les préférences paysagères d’un ensemble d’individus et (2) la connectivité écologique pour un ensemble d’espèces animales. En mobilisant de manière complémentaire des analyses statistiques multivariées et des analyses spatiales, le cœur du travail a ensuite consisté à étudier comment ces deux fonctions ont évolué de manière convergente ou divergente au cours du temps. Les résultats donnent de nouveaux éléments de compréhension des relations entre esthétique et écologie du paysage et amènent à s’interroger sur l’intérêt de la modélisation spatiale pour une gestion du paysage conciliant la préservation du cadre de vie des habitants et la conservation de la biodiversité. / Landscape is both a backdrop to the lives of human populations and a medium for the life cycle of animal species. Landscape changes induced by land-use and land-cover dynamics affect both these dimensions, the one aesthetic, and the other ecological. Because these rationales areusually studied within different disciplines, little research has been done into how the two clashor combine as and when landscape structures change. This work seeks therefore to model the spatial co-evolution of the aesthetic and ecological functions of landscape retrospectively usingspatial metrics based on land-cover data. It focuses on changes in the urban fringes of two French cities (Paris and Besançon) over the last 30 years. The approach attempts first to use land-cover data to model (1) the landscape preferences of a set of individuals and (2) the ecological connectivity of a set of animal species. Drawing on both multivariate statistical analysis and spatial analysis, the core of this work consists in investigating how the two functions have evolved in convergent or divergent ways over time. The results provide fresh insight into the relationship between landscape aesthetics and landscape ecology and raise questions about the value of spatial modelling for a landscape management approach that endeavours to reconcile the preservation of residents’ living environments and the conservationof biodiversity.

Les zones humides sont écosystèmes reconnus de vitale importance pour la conservation de la biodiversité et pour un développement soutenable. En Colombie, 26 % du territoire continental national est couvert de ces écosystèmes. Le complexe de zones humides urbaines de Bogota, en fait partie, avec 15 écosystèmes, dont la Convention Ramsar reconnaît 11. Ils sont uniques et jouent un rôle important dans l’approvisionnement des services écosystèmes à la zone urbaine. Cependant, ces écosystèmes urbains font face à de nombreux défis en raison de leur emplacement. Les causes et les conséquences de leur transformation sont très complexes. En appliquant des approches des systèmes complexes, sa dynamique de changement peut être étudiée. Les automates cellulaires sont l’une des techniques largement utilisées dans la modélisation de la dynamique spatiotemporelle des changements de l’usage et de l’occupation des sols. Cette étude propose l’analyse et la simulation des zones humides urbaines en appliquant une approche hybride par un modèle couplé de chaîne de Markov, de réseaux de neurones artificiels et d’automates cellulaires, afin d’estimer leurs changements d’étendue pour les années 2016, 2022, 2028 et 2034 dans la ville de Bogota, en Colombie. Pour extraire le changement d’occupation et d’utilisation du sol, trois images analogues des années 1998, 2004 et 2010 ont été a utilisées. Les résultats ont montré une diminution de 0,30 % de la couverture des zones humides en douze ans. De plus, les résultats suggèrent que la couverture des zones humides représentera 1,97 % de la zone d’étude totale en 2034, représentant une probabilité de diminution de 14 % en 24 ans. D’ailleurs, en appliquant l’analyse d’intensité, il a été constaté que le gain de cultures et de pâturages cible la perte de zones humides. Bien dont ces écosystèmes soient protégés et d’utilisation restreinte, leur patron de réduction se poursuivra en 2034. La pertinence de ce projet réside dans sa contribution potentielle au processus décisionnel au sein de la ville et en tant qu’instrument de gestion des ressources naturelles. En outre, les résultats de cette étude pourraient aider à atteindre l’objectif de développement durable 6 « Eau propre et assainissement » et l’atténuation du changement climatique. / Wetlands are ecosystems recognized as being of vital importance for the conservation of biodiversity and for sustainable development. In Colombia, 26% of the national continental territory is covered by these ecosystems. The complex of urban wetlands of Bogota is one of them, with 15 ecosystems, of which the Ramsar Convention recognizes 11. They are unique and play an important role in providing ecosystem services to the urban area. However, these urban ecosystems face many challenges due to their location. The causes and consequences of their transformation are very complex. By applying complex systems approaches, the dynamics of change can be studied. Cellular automata is one of the widely used techniques in modeling the spatiotemporal dynamics of land use and land cover changes. This study proposes the analysis and simulation of urban wetlands by applying a hybrid approach through a coupled model of the Markov chain, artificial neural networks, and cellular automata, in order to estimate the extent of changes for the years 2016, 2022, 2028, and 2034 in the city of Bogota, Colombia. To extract the change in land cover and land use, three analogous images from the years 1998, 2004, and 2010 were used. The results showed a 0.30% decrease in wetland coverage in twelve years. Furthermore, the results suggest that wetland cover will be 1.97% of the total study area in 2034, representing a 14% probability of a decrease in 24 years. Moreover, by applying the intensity analysis, it was found that the gain of crop and pastureland targets the loss of wetlands. Although these ecosystems are protected and of limited use, their pattern of reduction will continue in 2034. The relevance of this project lies in its potential contribution to decision-making within the city and as a natural resource management tool. In addition, the results of this study could help achieve Sustainable Development Goal 6 “Clean Water and Sanitation” and climate change mitigation.

Das Amazonasgebiet hat in den letzten Jahrzehnten eine Intensivierung der menschlichen Aktivitäten erfahren, die in Verbindung mit häufigen schweren Dürren die Umwelt anfälliger für Brände gemacht hat. In dieser Dissertation wurden Fernerkundungsdaten analysiert, um die räumlich-zeitliche Verteilung der Feuer in den letzten 20 Jahren im brasilianischen Amazonasgebiet umfassend zu untersuchen und die verschiedenen Brandursachen zu entschlüsseln. (I) Die erste Forschungsarbeit wertete die Verteilung der verbrannten Fläche aus und zeigte, dass die meisten Brände auf bewirtschafteten Weiden und in den immergrünen Tropenwäldern auftraten, was die Behauptung stützt, dass ihr Auftreten stark auf anthropogene Landnutzungsänderungen reagiert. Die Ergebnisse zeigten auch, dass weder Entwaldung noch Walddegradierung mit Waldbränden korrelierte, wohl aber Feuer, die auf Weiden oder Ackerflächen gelegt wurden und in den angrenzenden Wald übergesprungen sind. (II) Die zweite Forschungsarbeit analysierte einzelne Brände, die durch den auf komplexen Netzwerken basierenden FireTracks-Algorithmus identifiziert wurden. Der Algorithmus wurde verwendet, um Feuerregime für sechs verschiedene Landnutzungsklassen zu ermitteln. Die integrierte Größe, Dauer, Intensität und Ausbreitungsrate dieser räumlich-zeitlichen Brandcluster in den verschiedenen Landnutzungstypen zeigte auf, wie seltene Waldbrände, die natürlicherweise nicht in immergrünen tropischen Wäldern vorkommen, sich zu einem Feuerregime entwickelten, das für Savannenbrände typisch ist. (III) Die dritte Forschungsarbeit analysierte extreme, d. h. die intensivsten Einzelfeuer in immergrünen tropischen Wäldern, und zeigte deren großen Anteil an der insgesamt verbrannten Waldfläche. Während der globale Klimawandel das Potenzial hat, die Trockenheit zu verstärken, sind die anthropogenen Ursachen der Waldzerstörung die Zündquellen, die die Verteilung extremer Brände in den empfindlichen tropischen Wäldern bestimmen. / The Amazon region has experienced an intensification of human activities in the last decades, which combined with frequent severe droughts has led to an environment more susceptible to fire. Remotely sensed data is employed to comprehensively analyse the spatio-temporal fire distribution in the Brazilian Legal Amazon over the past 20 years to disentangle the diverse fire drivers in the region. Special focus is given to burned tropical evergreen forests.  (I) The evaluation of the burned area distribution revealed that most of it occurred in pastures and tropical evergreen forests, supporting the claim that fire incidence responds strongly to anthropogenic land-use changes. The results also showed that neither deforestation nor degradation correlated with forest fires, but escaping fires from pastures and agriculture do. (II) The analysis of individual fires identified by the complex networks based FireTracks algorithm led to the characterization of six different land cover-dependent fire regimes (fire size, duration, intensity, and rate of spread), which uncovered how evergreen forest fires have escalated from being naturally rare to showing characteristics more typical of savanna fires. (III) The analysis of extreme (most intense) fires in evergreen forests showed their large contribution to the total forest burned. While global climate change has the potential to increase drought conditions, anthropogenic drivers of forest degradation provide the ignition sources that determine extreme fire distribution in the tropical forests. The findings call for the development of control and monitoring plans to prevent fires from escaping from managed lands into forests, better management techniques to support effective land use and ecosystem management, targeting forest degradation in addition to deforestation, and considering the human factor in fire ignition and spread in Dynamic Global Vegetation Models in order to reduce uncertainty in fire regime projections.