References of "Vranken, Isabelle"
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See detailAnthropogenic effects on African Landscapes: Spatial Structure, Typologies, Ecological Impact
Vranken, Isabelle ULg

Poster (2014, February)

The problematique of anthropogenic disturbance on African landscapes is studied within the double framework of DPSIR (Drivers Pressures States Impact Response) and Pattern/Process Paradygm (Landscape ... [more ▼]

The problematique of anthropogenic disturbance on African landscapes is studied within the double framework of DPSIR (Drivers Pressures States Impact Response) and Pattern/Process Paradygm (Landscape Ecology). 20 landscae images from D.R. Congo, Ivory Coast and Benin were studied using indexes of spatial (compositional and configurational) heterogeneity and anthropogenic disturbance in order to highlight the relationship between spatial structure and disturbance intensity. The results show maximal heterogeneity at intermediate anthropogenic disturbances and fasten the triangular relationship between anthropogenic effect, biodiversity and spatial heterogeneity, that had been partially theoretised with the intermidiate disturbance and habitat heterogeneity hypotheses. [less ▲]

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See detailA review on the use of entropy in landscape ecology: heterogeneity, unpredictability, scale dependence and their links with thermodynamics
Vranken, Isabelle ULg; Baudry, Jacques; Aubinet, Marc ULg et al

in Landscape Ecology (2014)

The identification of a universal law that can predict the spatiotemporal structure of any entity at any scale has long been pursued. Thermodynamics have targeted this goal, and the concept of entropy has ... [more ▼]

The identification of a universal law that can predict the spatiotemporal structure of any entity at any scale has long been pursued. Thermodynamics have targeted this goal, and the concept of entropy has been widely applied for various disciplines and purposes, including landscape ecology. Within this discipline, however, the uses of the entropy concept and its underlying assumptions are various and are seldom described explicitly. In addition, the link between this concept and thermodynamics is unclear. The aim of this paper is to review the various interpretations and applications of entropy in landscape ecology and to sort them into clearly defined categories. First, a retrospective study of the concept genesis from thermodynamics to landscape ecology was conducted. Then, 50 landscape ecology papers that use or discuss entropy were surveyed and classified by keywords, variables and metrics identified as related to entropy. In particular, the thermodynamic component of entropy in landscape ecology and its various interpretations related to landscape structure and dynamics were considered. From the survey results, three major definitions (i.e., spatial heterogeneity, the unpredictability of pattern dynamics and pattern scale dependence) associated with the entropy concept in landscape ecology were identified. The thermodynamic interpretations of these definitions are based on different theories. The thermodynamic interpretation of spatial heterogeneity is not considered relevant. The thermodynamic interpretation related to scale dependence is also questioned by complexity theory. Only unpredictability can be thermodynamically relevant if appropriate measurements are used to test it. [less ▲]

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See detailAnthropogenic effects in landscapes: Historical context and spatial pattern
Bogaert, Jan ULg; Vranken, Isabelle ULg; Andre, Marie ULg

in Hong, S.-K.; Bogaert, Jan; Min, Q. (Eds.) Biocultural Landscapes: Diversity, Functions and Values (2014)

Bio-cultural landscapes are characterized by anthropogenic pattern features, of which the measurement constitutes a key step in landscape analysis. Metrics and strategies for this measurement of ... [more ▼]

Bio-cultural landscapes are characterized by anthropogenic pattern features, of which the measurement constitutes a key step in landscape analysis. Metrics and strategies for this measurement of anthropogenic patterns and their dynamics are discussed, considering the pattern/process paradigm, the patch-corridor- matrix model and the complementarity of landscape composition and configuration as conceptual benchmarks. Historically, noticeable anthropogenic effects are accepted to have appeared in landscapes after the invention of agriculture and further trends of landscape change could be linked to the development of agriculture. Through time, a sequence of landscape dynamics with three stages is expected, in which a natural landscape matrix is initially substituted by an agricultural one; urban patch types will later on dominate the matrix as a consequence of ongoing urbanization. The importance of the development of agriculture and its productivity for the evolution of settlements, villages and cities is emphasized. Anthropogenic change of landscapes confirms the status of geographical space as a limited resource. [less ▲]

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See detailSpatial patterns and morphology of termite ( Macrotermes falciger ) mounds in the Upper Katanga, D.R. Congo
Mujinjya, Baile Baziraké; Adam, Marielle; Mees, Florias et al

in Catena (2014), 114

This study examines the spatial distribution patterns and morphological characteristics of Macrotermes falciger mounds in the peri-urban zone of Lubumbashi, D.R. Congo. Spatial patterns of mounds were ... [more ▼]

This study examines the spatial distribution patterns and morphological characteristics of Macrotermes falciger mounds in the peri-urban zone of Lubumbashi, D.R. Congo. Spatial patterns of mounds were assessed using high-resolution satellite images for 24 plots of variable size (3 to 27 ha). Soil morphological features were described for five termite-mound profiles of 5 to 9 m depth/height. A mean areal number density of 2.9 ± 0.4 mounds ha−1 is estimated for the degraded miombo woodland of the study area. Spatial statistical analyses document that termite mounds are regularly distributed in all studied plots. The overall mean nearest-neighbour distance between termite mounds is 44.6 ± 0.6 m. The high relative number of inactive mounds in the region, with regular distribution patterns, suggests that current termite mound occurrences are largely relict features.There are no clear indications for an impact of the nature of the parent material on the spatial distribution of the mounds. One aspect of differences in morphology between the studied mounds is that the stone layer occurs at greater depth in topographic low areas than at crest and slope positions. This is interpreted as being mainlyconditionedbyerosion.Mn–Fe oxideconcentrationsoccurringinallstudiedtermite moundprofiles reflect a seasonally high perched water table beneath the mound, which is more pronounced at lower landscape positions. In summary, mound positions in the habitat are consistent with intraspecific competition rather than soil and substrate characteristics as controlling factor, whereas variation in morphological characteristics between termite-mound profiles appears to be a function of the parent material [less ▲]

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See detailEcologie du paysage, anthropisation en Afrique tropicale, instruments et études de cas
Vranken, Isabelle ULg

Scientific conference (2013, November)

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See detailThe spatial footprint of the non-ferrous mining industry of Lubumbashi
Vranken, Isabelle ULg; Munyemba, François K.; Amisi, Mwana Y.

Conference (2013, September 06)

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known “Copper Belt”. Industrial mining and ... [more ▼]

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known “Copper Belt”. Industrial mining and smelting plants were installed under Belgian colonialism in the area and numerous other international companies have settled there since the end of the 1990s. Due to dominant south-eastern winds, the metallurgic industry in Lubumbashi has been the source of spatially concentrated atmospheric deposits of non ferrous metal particles and associated substances in a cone-shaped zone, situated north-west of the original metal processing site. Though an empiric effect on vegetation had been noticed for decades, it had not been highlighted yet until recently that this was due to the metallurgic activity. The metal processing plant has dramatically reduced its activity after the independence, in 1960, but the results of the colonial period and current activity are still visible today. The existence of this pollution cone has then been evidenced using two different techniques. Firstly, landscape metric comparisons of the vegetation and bare soil patterns in two study areas, one inside the pollution cone and one outside, have been applied on basis of a classified Quickbird satellite image (2005). Secondly, the city perception theory developed by Kevin Lynch has been used and adapted to the pollution issue and the context of developing countries, using trained experts and interviewed citizens. The first method highlighted a higher fragmentation and lower vegetation presence inside the pollution cone, reflecting the negative impact of the atmospheric deposits. Those differences were higher for sites closer to the emission source. Lynch’s approach outlined the negative impact of diverse industrial plants on the perception by the local population. Six pollution districts and several contaminated paths, limits, nodes and polluting landmarks were identified. Those included the recently installed plants to the north and east of the city. Citizens even recognize them as part of the collective image of the city. This has important outcomes, as the demographic pressure in Lubumbashi extended the city limits so that the metal processing plant is now fully included in the urban matrix. Therefore, a part of the local population lives within the pollution cone and faces contamination. Moreover, the rivers flowing near the plant, Kafubu and Lubumbashi, as well as the roads and railways linking different industrial sites are contaminated and represent contamination paths potentially spreading toxic substances all over the area. Sanitary evidences of this contamination have already been found in the area and particularly the pollution cone. Moreover, the recently installed plants, outside of the city, could face the same problems due to urban sprawl in the forthcoming years. This should be taken into account for the urban planning in Lubumbashi. Evidencing the ecological footprint of the non-ferrous mining industry is considered crucial to confront local decision makers with the negative impact of metallurgic industry within an urban context. [less ▲]

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See detailOn the definitions and interpretations of Entropy in Landscape ecology: A review
Vranken, Isabelle ULg

Conference (2013, July)

Landscape ecology studies the structure of landscapes as interacting ecosystems over space and time. Thanks to Turner's Pattern / process paradigm, it allows inferring ecological impacts of disturbances ... [more ▼]

Landscape ecology studies the structure of landscapes as interacting ecosystems over space and time. Thanks to Turner's Pattern / process paradigm, it allows inferring ecological impacts of disturbances observable through land use change. The purpose of this research is to use landscape ecology techniques based on remote sensing to assess the ecological impacts of anthropogenic effects such as urban growth and agriculture extension on subtropical African landscapes, characterised by fast unplanned growth and subsequent prevailing menace on the rich local environmental resources and biodiversity. Taken from information theory and generally used to assess disturbances of any kind, the concept of entropy is important in landscape ecology and also used in many other disciplines for other purposes. It turns out however that it is used in many different ways and interpreted within various, sometimes opposed definitions and that the context in which it is used is not always explicit. The purpose of the present intervention is therefore to review the different interpretations and applications of entropy in landscape ecology and sort them into different clearly defined categories. Forty landscape ecology articles and book chapters using or discussing entropy have been surveyed and classified by keywords, variables and indexes mentioned to relate entropy. The connection relevance between those interpretations has also been examined through this literature sample and other reference works on entropy. Particularly, the thermodynamic component of entropy in landscape ecology and its different interpretations as for landscape structure and evolution is questioned. This fundamental research issue represents a preliminary survey to researches on the structural impact of anthropogenic disturbances. Indeed, according to the Naiman habitat heterogeneity hypothesis, a higher spatial heterogeneity within the landscape would have a positive influence on species diversity. This has important outcomes to study ecosystem resilience to anthropogenic disturbances and combine human development with biological conservation. [less ▲]

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See detailThe spatial footprint of the non-ferrous metal industry in Lubumbashi
Vranken, Isabelle ULg; Munyemba Kankumbi, François; Amisi Mwana, Yamba et al

in Tropicultura (2013), 31(1), 20-27

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known “Copper Belt”. Due to the dominant ... [more ▼]

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known “Copper Belt”. Due to the dominant south-eastern winds, the metallurgic industry in Lubumbashi has been the source of spatially concentrated atmospheric deposits of non-ferrous metal particles and associated substances in a cone-shaped zone, situated north-west of the metal processing site. The existence of this zone has been evidenced using two different techniques: firstly, by means of landscape metric comparisons of the vegetation and bare soil patterns in two study areas, one inside the pollution cone and one outside; secondly, by means of the theory on city perception developed by Kevin Lynch. Higher fragmentation and lower vegetation presence were observed inside the pollution cone, reflecting the negative impact of atmospheric deposits. Those differences were higher for sites closer to the emission source. Lynch’s approach outlined the negative impact of diverse industrial plants on the perception by the local population. Six pollution districts and several contaminated paths, limits, nodes and polluting landmarks were identified. Citizens even recognize them as part of the collective image of the city. [less ▲]

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See detailIntroduction aux théories de la perception du paysage
Vranken, Isabelle ULg

Speech (2012)

La perception du paysage est abordée sous l'angle de l'école behavioriste, plus particulièrement les travaux de Kevin Lynch en urbanisme sur l'image de la ville. Elle part du postulat que la perception de ... [more ▼]

La perception du paysage est abordée sous l'angle de l'école behavioriste, plus particulièrement les travaux de Kevin Lynch en urbanisme sur l'image de la ville. Elle part du postulat que la perception de l'environnement influence le comportement de l'individu qui y vit (le citoyen)et modifie à son tour son environnement. Ceci sert à dégager des principes d'aménagement du territoire pour plus de bien-être. La voirie joue un rôle central dans la perception de la ville, étant donné que c'est le point d'observation principal de celle-ci par les citoyens. Selon sa forme, ses accès et ses abords, ou encore l'organisation de l'écran construit, différents effets d'ambiance urbaine peuvent être ménagés. Dans ce paysage s'implantent les éléments principaux de la structure de la ville: limites, voies, noeuds, points de repère, quartiers. Leur organisation relative fait émerger les caractéristiques globales de la ville que sont la lisibilité et l'imagibilité. Ces techniques ont été utilisées et adaptées pour l'analyse de la ville de Lubumbashi et de l'Avenue Louise à Bruxelles. [less ▲]

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See detailCone de pollution à Lubumbashi: trois techniques pour le mettre en évidence
Vranken, Isabelle ULg

Speech (2012)

A cause des vents dominants de secteur Sud-Est, l'industrie métallurgique de Lubumbashi a été la source de dépôts atmosphériques spatialement concentrés en une zone conique, située au nord-ouest de la ... [more ▼]

A cause des vents dominants de secteur Sud-Est, l'industrie métallurgique de Lubumbashi a été la source de dépôts atmosphériques spatialement concentrés en une zone conique, située au nord-ouest de la fonderie de la Gécamines. Premièrement, l'existence de ce cône a été mise en évidence en utilisant des comparaisons de structure de la végétation et des sols nus dans deux zones d'étude : dans le cône de pollution et en dehors. Ensuite, dans une étude plus large et plus qualitative, une adaptation des théories de la perception urbaine de Kevin Lynch. Une présence plus faible et plus fragmentée de végétation dans le cône qu'hors du cône est détectée. De plus, un e ffet de la proximité à la source a été détecté. Deuxièmement, l'approche de Kevin Lynch a mis en évidence l'impact non seulement de l'activité de l'usine Gécamines, mais également des autres sites industriels installés plus récemment dans la région. Pour isoler davantage l'e ffet de la pollution atmosphérique liée à la cheminée des Gécamines par rapport à celui des autres usines ou de la coupe de bois de feu, l'utilisation des modèles neutres est envisagée. [less ▲]

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See detailCône de pollution à Lubumbashi: mise en évidence à partir de la structure spatiale de la végétation et de la perception paysagère
Vranken, Isabelle ULg

Speech (2012)

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known ¿Copper Belt¿. Due to the dominant ... [more ▼]

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known ¿Copper Belt¿. Due to the dominant south-eastern winds, the metallurgic industry in Lubumbashi has been the source of a spatially concentrated atmospheric deposits of non-ferrous metal particles and associated substances in a cone-shaped zone, situated north-west of the metal processing site. The existence of this zone has been evidenced using two different techniques: firstly, by means of landscape metric comparisons of the vegetation and bare soil patterns in two study areas, one inside the pollution cone and one outside; secondly, by means of the theory on city perception developed by Kevin Lynch. Higher fragmentation and lower vegetation presence were observed inside the pollution cone, reflecting the negative impact of atmospheric deposits. Those differences were higher for sites closer to the emission source. Lynch¿s approach outlined the negative impact of diverse industrial plants on the perception by the local population. Six pollution districts and several contaminated paths, limits, nodes and polluting landmarks were identified. Citizens even recognize them as part of the collective image of the city. [less ▲]

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See detailEntropie et anthropisation des paysages : interprétations, usages, interrelations
Vranken, Isabelle ULg

Scientific conference (2012, November 07)

La notion d'entropie en écologie du paysage est fréquemment utilisée, notamment pour caractériser l'effet des perturbations anthropiques. Or il s'avère que ce concept puisse y prendre des sens multiples ... [more ▼]

La notion d'entropie en écologie du paysage est fréquemment utilisée, notamment pour caractériser l'effet des perturbations anthropiques. Or il s'avère que ce concept puisse y prendre des sens multiples et parfois contradictoires, notamment en ce qui concerne le lien entre entropie thermodynamique et hétérogénéité spatiale du paysage. Ce séminaire présente les différentes interprétations de l'entropie en écologie du paysage et dans d'autres disciplines, puis tente d'établir des liens entre elles, plus particulièrement avec la thermodynamique. En outre, un lien entre l'entropie (hétérogénéité spatiale, puis thermodynamique) et l'anthropisation est établi à l'aide d'indices de structure spatiale (Simpson, LPI, U) appliqués à une population de 16 paysages africains. Il en ressort que l'effet anthropique a tendance à augmenter l'hétérogénéité spatiale du paysage pour atteindre un optimum à l'équilibre entre classes anthropiques et naturelles et ensuite diminuer. L'étude des liens entre hétérogénéité spatiale et thermodynamique montre qu'en l'état actuel des connaissances, il n'est pas pertinent d'établir un lien unilatéral entre ces deux champs d'observation. [less ▲]

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See detailAnthropisation des paysages: Structure spatiale, impact écologique, entropie
Vranken, Isabelle ULg; Bogaert, Jan ULg; Visser, Marjolein

Poster (2012, February 29)

Structural and thermodynamic applications of entropy related to spatial heterogeneity under growing anthropogenic pressure have been examined. 16 zones from classified LANDSAT TM scenes presenting ... [more ▼]

Structural and thermodynamic applications of entropy related to spatial heterogeneity under growing anthropogenic pressure have been examined. 16 zones from classified LANDSAT TM scenes presenting different anthropogenic effect intensities have been used. Anthropogenic effects, compositional and configurational entropy have been measured. The scatter plot shows bell curves with maximal entropy at intermediate anthropogenic effects. Distinction of natural and anthropogenic classes shows opposed tendencies according to class and compositional/configurational type. These results have been interpreted as spatial transformation processes, energy production and release, and linked to the habitat heterogeneity and intermediate disturbance hypotheses. [less ▲]

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See detailAnthropogenic effect on landscapes: spatial structure, ecological impact, entropy
Vranken, Isabelle ULg; Bogaert, Jan ULg; Visser, Marjolein

Poster (2012, February 10)

Structural and thermodynamic applications of entropy related to spatial heterogeneity under growing anthropogenic pressure have been examined. 16 zones from classified LANDSAT TM scenes presenting ... [more ▼]

Structural and thermodynamic applications of entropy related to spatial heterogeneity under growing anthropogenic pressure have been examined. 16 zones from classified LANDSAT TM scenes presenting different anthropogenic effect intensities have been used. Anthropogenic effects, compositional and configurational entropy have been measured. The scatter plot shows bell curves with maximal entropy at intermediate anthropogenic effects. Distinction of natural and anthropogenic classes shows opposed tendencies according to class and compositional/configurational type. These results have been interpreted as spatial transformation processes, energy production and release, and linked to the habitat heterogeneity and intermediate disturbance hypotheses. [less ▲]

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See detailStructure spatiale et impact écologique des processus d'anthropisation des paysages terrestres: développement d'une instrumentation générique d'analyse
Vranken, Isabelle ULg

Scientific conference (2011, September 06)

The current project aims to develop a generic set of analysis methods to quantify anthropogenic degradation of tropical ecosystems. This will assist in landscape planning for ecosystem restoration and ... [more ▼]

The current project aims to develop a generic set of analysis methods to quantify anthropogenic degradation of tropical ecosystems. This will assist in landscape planning for ecosystem restoration and sustainable management of human impacts. Indeed, the analysis methods will enable to detect landscape degradation and its anthropogenic drivers based on their spatial properties, less complex or expensive to obtain than in-situ data. The project consists of two parts: - methodological research and development, based on principles landscape ecology and combined with other disciplines like remote sensing, geographic information systems, sociology and agronomy (in progress), - application of the developed pattern metrics on new study cases for evaluation and validation. Using study cases in tropical areas, the development of a typology enables to identify, classify and analyze degradation origin, its spatial properties and the ecosystems involved. The following pressures: woodcut for charcoal production, agricultural extension, mining activity and climate change have already been tested for the following natural ecosystems: rainforest, woodland, savannah. Afterwards, different metrics will be evaluated statistically with regard to their potential to capture anthropogenic effects. The Simpson diversity index, Largest Patch Index, fractal dimension and O'Neill disturbance index have already been tested and sometimes adapted. Critical thresholds will be defined in order to detect critical degradation levels of the terrestrial ecosystems. The best metrics will be calculated for new case(s) of anthropogenic impacts on landscapes (Cambodia?) in order to validate the correlation between metric outcomes and in situ observations. [less ▲]

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See detailMaximum entropy at intermediate anthropogenic dynamics
Vranken, Isabelle ULg; Bogaert, Jan ULg

in Jones, Bruce; Fu, Bojie (Eds.) The 8th World congress of the International Association of Landscape Ecology: Proceedings, Beijing, August 18-23, 2011 (2011, August 20)

Landscape entropy represents heterogeneity within a landscape (Renyi, 1961; Bogaert et al., 2005). Previous researches found increasing values of entropy by studying a limited number of zones increasingly ... [more ▼]

Landscape entropy represents heterogeneity within a landscape (Renyi, 1961; Bogaert et al., 2005). Previous researches found increasing values of entropy by studying a limited number of zones increasingly affected by anthropogenic effect (O’Neill et al., 1988; Bogaert et al., 2005). The present research aims to generalise the relationship between anthropogenic effect and landscape entropy, with a further goal of linking these concepts to overall biodiversity. 16 study zones from classified LANDSAT TM scenes and Africover maps presenting different anthropogenic effect intensities have been used (Djibu et al., 2008; Bamba et al., 2010; Barima et al., 2010; Munyemba, 2010; Vranken et al., 2011). Simpson's H diversity index based on class number has been used for entropy measurement (Renyi, 1961; Pielou, 1975; Shannon and Weaver, 1963). 1-H has been retained to get the relationship between the index and diversity directly proportional. For anthropogenic effect measurement, O’Neill’s U disturbance index, quotient between anthropogenic and natural areas, has been used (O’Neill et al., 1988). Log H has been retained to linearise the exponential relationship between the index and anthropogenic effect. Correlation between those variables has then been analysed. The scatter plot of the 16 study zones shows a Gaussian curve (Fig. 1) presenting maximal landscape entropy at intermediate anthropogenic effect. This distribution has been modelled by a second order polynomial regression with determination coefficient and significance. This phenomenon has been interpreted in terms of spatial transformation processes (Bogaert et al., 2004) and linked to the habitat heterogeneity hypothesis (Tews, 2004), as well as the intermediate disturbance hypothesis (Connell, 1978; Lindenmayer and Brugman, 2005). [less ▲]

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See detailIdentification and Measurement of Anthropogenic Effects in Landscapes
Bogaert, Jan ULg; Vranken, Isabelle ULg; Bastin, Jean-François ULg et al

in Jones, Bruce; Fu, Bojie (Eds.) The 8th World congress of the International Association of Landscape Ecology: Proceedings, Beijing, August 18-23, 2011 (2011, August 20)

As a consequence of anthropogenic pressure, landscapes change; deforestation is a well-known example of this type of human-driven landscape change. Landscapes change 42 from entirely natural to ... [more ▼]

As a consequence of anthropogenic pressure, landscapes change; deforestation is a well-known example of this type of human-driven landscape change. Landscapes change 42 from entirely natural to anthropogenic or cultural, in which landscape composition is marked by land covers and uses directly related to the civil society, such as degraded vegetations, agriculture, urban zones, or road networks. Landscape dynamics can be quantified by landscape pattern analysis. Many landscape metrics are available to capture the different features of pattern change. As a consequence of the pattern/process paradigm, the ecological consequences of the observed dynamics can be linked to ecosystem processes and characteristics, such as biodiversity. By means of a series of case studies linking field observations of fauna and flora with cartographic and demographic data, the importance of pattern analysis and landscape management is underlined, as well as the diversity in types of anthropogenic landscape change. Conclusions are drawn with regard to the ecological impact of landscape change. Guidelines are formulated for the characterization and analysis of anthropogenic effects in landscapes by means of pattern analysis. [less ▲]

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See detailStructure spatiale et impact écologique des processus d'anthropisation des paysages terrestres: développement d'une instrumentation générique d'analyse
Vranken, Isabelle ULg; Bogaert, Jan ULg

Poster (2011, March 28)

The current research project aims to develop a generic set of analysis methods which enables to characterize quantitatively anthropogenic degradation of terrestrial ecosystems. This characterization will ... [more ▼]

The current research project aims to develop a generic set of analysis methods which enables to characterize quantitatively anthropogenic degradation of terrestrial ecosystems. This characterization will assist in landscape planning oriented towards a sustainable management of human impacts and towards a restoration of degraded ecosystems. The analysis methods will enable to detect landscape degradation and its anthropogenic drivers based on their spatial properties, a type of information that is less complex and less expensive to obtain than ecological data collected in situ. The project is composed of two parts: (1) methodological research and development, based on the principles of landscape ecology and combined with other disciplines like remote sensing, geographic information systems, sociology and agronomy; (2) application of the developed pattern metrics on new study cases for evaluation and validation. Using study cases of degradation situated worldwide, the development of a typology will enable to identify, classify and analyze the causes of degradation, their spatial properties and the ecosystems involved. These study cases will be chosen based on the types of ecosystems degraded, the spatial scale of degradation, the climatic zone, and the intensity and speed of landscape degradation. Every type will be analyzed with regard to its impact on spatial pattern. Afterwards, the different metrics will be evaluated statistically for comparison with regard to their potential to capture anthropogenic effects. The development of new metrics is hereby not excluded. Critical thresholds will be defined in order to detect critical degradation levels of the terrestrial ecosystems. The best metrics selected in this way will be calculated for new cases of anthropogenic impacts on landscapes, cases selected by application of the aforementioned typology, in order to validate the correlation between metric outcomes and in situ observations. [less ▲]

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See detailEcological impact of habitat loss on African landscapes and diversity
Vranken, Isabelle ULg; Djibu Kabulu, J P; Munyemba Kankumbi, F et al

in Daniels, J A (Ed.) Advances in environmental research, volume 14 (2011)

Detailed reference viewed: 79 (28 ULg)