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See detailAnthracologie : perturbations passées et évolution de la végétation
Morin-Rivat, Julie ULg

in CoForChange - La Lettre (2012)

Mettre en évidence la relation entre occupation humaine et distribution de la végétation est l’un des points abordés par CoForChange. Les récentes études montrent que les perturbations anthropiques ont eu ... [more ▼]

Mettre en évidence la relation entre occupation humaine et distribution de la végétation est l’un des points abordés par CoForChange. Les récentes études montrent que les perturbations anthropiques ont eu une influence sur la végétation, permettant notamment l’expansion des espèces héliophiles (cf. Lettre n° 4). Pour contribuer à cette analyse dans un contexte de grande rareté des données anthracologiques en Afrique, nous avons, dans le cadre d’un master, choisi d’étudier les charbons de bois issus de neuf fosses pédologiques du projet CoForChange. L’objectif était d’appréhender les compositions floristiques actuelle et passée des forêts au regard des perturbations passées. Deux protocoles anthracologiques d’identification ont été testés : a) à l’échelle de l’espèce, par une description des caractères anatomiques des charbons de bois, une recherche sur la base de données en ligne InsideWood et une comparaison anatomique au Xylarium de Tervuren ; b) à l’échelle de la communauté, par une recherche des relations statistiques entre traits écologiques des espèces et anatomie du bois. Les résultats montrent que la diversité taxonomique sous les forêts à Marantaceae est plus grande que sous les forêts denses de terre ferme. Trois identifications ont été obtenues sur 48 taxons décrits : Gilbertiodendron dewevrei sous forêt monodominante à G. dewevrei (GIB1 à 40 cm de profondeur, 1 510 ± 30 années cal. BP (calibrated before present), Millettia drastica et Pterocarpus soyauxii sous forêt clairsemée à Marantaceae (F9 à 40 cm, 1 200 ± 30 cal. BP). Notre hypothèse est que les peuplements monodominants à G. dewevrei sont relativement stables. Quant à P. soyauxii, la proportion de cette espèce héliophile semble décroître au cours du temps (niveaux entre 20 et 40 cm) au profit desMarantaceae. Un autre résultat porte sur l’absence de Triplochiton scleroxylon sous T. scleroxylon, ce qui pourrait confirmer l’hypothèse du caractère récent de ces peuplements. Les résultats portant sur la relation entre anatomie du bois et traits fonctionnels restant préliminaires, cette recherche sera poursuivie en thèse de doctorat. Les développements actuels de l’anthracologie pour l’Afrique tropicale permettent désormais d’envisager un plus grand nombre d’identifications par échantillon et ainsi une meilleure connaissance de l’évolution des forêts tropicales. [less ▲]

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See detailAnthracology: past disturbances and vegetation evolution
Morin-Rivat, Julie ULg

in CoForChange - Newsletter (2012)

One of CoForChange aims is to highlight the relationship between human settlement and plant distribution. Recent studies show that anthropogenic disturbances have had an impact on vegetation, including ... [more ▼]

One of CoForChange aims is to highlight the relationship between human settlement and plant distribution. Recent studies show that anthropogenic disturbances have had an impact on vegetation, including enabling the expansion of light-demanding species (see Newsl. No 4). To contribute to this analysis in a context of deep scarcity of anthracological data in Africa, we have been studying the charcoals from nine soil pits of the CoForChange project as part of a Master’s. The objective was to understand past and present species composition of the forests in relation with past disturbances. Two anthracological protocols of identification were tested: 1) at species level, by describing the anatomical characteristics of charcoals, by carrying investigations with InsideWood online database, and by comparing anatomical data at XylariumTervuren; 2) at community level, by searching for statistical relationships between ecological traits of species and wood anatomy. The results show that the taxonomic diversity is greater in Marantaceae forests than in lowland forests. Three identifications were obtained from 48 described taxa: Gilbertiodendron dewevrei under G. dewevrei monodominant forest (GIB1 at 40 cm depth, 1510 ± 30 years cal. BP), Millettia drastica and Pterocarpus soyauxii inMarantaceae open forests (F9 at 40 cm, 1200 ± 30 cal. BP). Our hypothesis is that monodominant stands of G. dewevrei are relatively stable. With regard to P. soyauxii, the proportion of this lightdemanding species seems to be decreasing over time (at levels from 20 to 40 cm) for the benefit of Marantaceae. Another result highlights the absence of Triplochiton scleroxylon under T. scleroxylon, which may confirm the hypothesis of the recent settlement of this species. Results on the relationship between wood anatomy and functional traits are still preliminary, and further research will be conducted through a PhD programme. The on-going developments of anthracology in tropical Africa will help to identify a larger number of collected samples, and thus to understand better the evolution of tropical forests. [less ▲]

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See detailAnthrax et charbon
Arrese, J. E.; Pierard-Franchimont, Claudine ULg; Pierard, Gérald ULg

in Revue Médicale de Liège (2001), 56(10), 685-8

Anthrax is a name given in French language to two distinct infectious diseases. One corresponds to carbuncle which is a collection of boils. The other one corresponds to the English term anthrax. This ... [more ▼]

Anthrax is a name given in French language to two distinct infectious diseases. One corresponds to carbuncle which is a collection of boils. The other one corresponds to the English term anthrax. This condition has a clinical presentation and an outcome that vary according to the inoculation site being cutaneous, pulmonary or digestive, and to the bacterial and toxin spread in the body. [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 detailL'anthropisation du paysage et ses impacts sur les écosystèmes forestiers
Bogaert, Jan ULg; Andre, Marie ULg; Lejeune, Philippe ULg et al

Conference (2012, October 24)

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See detailAnthropisation et dynamique des paysages en zone soudanienne au nord du Bénin
Mama, A; Sinsin, B; De Cannière, C et al

in Tropicultura (2013), 31(1), 78-88

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See detailAnthropisation et effets de lisière: impacts sur la diversité des rongeurs dans la Réserve forestière de Masako (Kisangani, R.D. Congo)
Iyongo Waya Mongo, L; Visser, M; De Cannière, C et al

in Tropical Conservation Science (2012), 5(3), 270-283

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See detailAnthropisation et effets de lisière: impacts sur la diversité des rongeurs dans la réserve forestière de Masako (Kisangani, RDC)
Iyongo, L; Visser, M; Verheyen, E et al

Poster (2012)

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See detailAn Anthropo-based Standpoint on Mediating Objects: Evolution and Extension of Industrial Design Practices.
Elsen, Catherine ULg; Darses, Françoise; Leclercq, Pierre ULg

in Gero, John (Ed.) Design Computing and Cognition '10 (2010)

This paper questions the new uses of design tools and representations in the industrial field. A two months in situ observation of real industrial practices shows (i) how strongly CAD (Computer-Aided ... [more ▼]

This paper questions the new uses of design tools and representations in the industrial field. A two months in situ observation of real industrial practices shows (i) how strongly CAD (Computer-Aided Design) tools are integrated in work practices, in preliminary design phases as well, and (ii) how design actors sometimes deviate this tool from its initial objectives to use it in complement of sketches’ contributions. A multi-layered study built on an anthropo-based approach helps us to deepen the “mediating objects” analysis. It also suggests considering the complementarities of design tools instead of their differences in order to propose another kind of design support tool. [less ▲]

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See detailAn anthropo-based study of industrial design cooperative practices using "mediating objects"
Elsen, Catherine ULg; Dawans, Arnaud ULg; Leclercq, Pierre ULg

in Lecture Notes in Computer Science (2010), 6240

This paper presents a two months in situ case study analyzing the characteristics of designers’ cooperative work through the use of “mediating objects”. We suggest that the consideration of real and ... [more ▼]

This paper presents a two months in situ case study analyzing the characteristics of designers’ cooperative work through the use of “mediating objects”. We suggest that the consideration of real and evolutionary practices and everyday complementary work tools helps to understand the various cooperative modalities between co-workers and offers good clues for the development of cooperative support systems. [less ▲]

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See detailThe Anthropocene and the Global Environmental Crisis. Rethinking modernity in a new epoch.
Hamilton, Clive; Bonneuil, Christophe; Gemenne, François ULg

Book published by Routledge (2015)

The Anthropocene, in which humankind has become a geological force, is a major scientific proposal; but it also means that the conceptions of the natural and social worlds on which sociology, political ... [more ▼]

The Anthropocene, in which humankind has become a geological force, is a major scientific proposal; but it also means that the conceptions of the natural and social worlds on which sociology, political science, history, law, economics and philosophy rest are called into question. The Anthropocene and the Global Environmental Crisis captures some of the radical new thinking prompted by the arrival of the Anthropocene and opens up the social sciences and humanities to the profound meaning of the new geological epoch, the ‘Age of Humans’. Drawing on the expertise of world-recognised scholars and thoughtprovoking intellectuals, the book explores the challenges and difficult questions posed by the convergence of geological and human history to the foundational ideas of modern social science. If in the Anthropocene humans have become a force of nature, changing the functioning of the Earth system as volcanism and glacial cycles do, then it means the end of the idea of nature as no more than the inert backdrop to the drama of human affairs. It means the end of the ‘social-only’ understanding of human history and agency. These pillars of modernity are now destabilised. The scale and pace of the shifts occurring on Earth are beyond human experience and expose the anachronisms of ‘Holocene thinking’. The book explores what kinds of narratives are emerging around the scientific idea of the new geological epoch, and what it means for the ‘politics of unsustainability’. [less ▲]

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See detailAnthropogenic and naturally-produced organobrominated compounds in marine mammals from Brazil
Dorneles, Paulo R; Lailson-Brito, José; Dirtu, Alin C et al

in Environment International (2010), 36(1), 60-67

Liver samples from 51 cetaceans, comprising 10 species, stranded between 1994 and 2006 in a highly industrialized and urbanized region in Southeast Brazil, were analyzed for polybrominated diphenyl ethers ... [more ▼]

Liver samples from 51 cetaceans, comprising 10 species, stranded between 1994 and 2006 in a highly industrialized and urbanized region in Southeast Brazil, were analyzed for polybrominated diphenyl ethers (PBDEs) and methoxylated-PBDEs (MeO-PBDEs). A concentration range of PBDEs (3-5960 ng/g lw) similar to that observed in Northern Hemisphere dolphins was found. MeO-PBDE concentrations in continental shelf (CS) dolphins from Brazil are among the highest detected to date in cetaceans (up to 250 µg/g lw). Higher [Sigma]MeO-PBDE concentrations were measured in CS and oceanic dolphins than in estuarine dolphins. The [Sigma]PBDE/[Sigma]MeO-PBDE ratio varied significantly ranging from a mean value of 7.12 to 0.08 and 0.01 for estuarine, CS and oceanic species, respectively. A positive correlation was observed between [Sigma]PBDE and year of stranding of male estuarine dolphins (Sotalia guianensis), which suggests temporal variation in the exposure. Placental transfer of organobrominated compounds was also evidenced in S. guianensis. [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 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 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 detailAnthropogenic forcing dominates global mean sea-level rise since 1970
Slagen, A.; Church, J.; Agosta, Cécile ULg et al

in Nature Climate Change (2016)

Sea-level change is an important consequence of anthropogenic climate change, as higher sea levels increase the frequency of sea-level extremes and the impact of coastal flooding and erosion on the ... [more ▼]

Sea-level change is an important consequence of anthropogenic climate change, as higher sea levels increase the frequency of sea-level extremes and the impact of coastal flooding and erosion on the coastal environment, infrastructure and coastal communities1, 2. Although individual attribution studies have been done for ocean thermal expansion3, 4 and glacier mass loss5, two of the largest contributors to twentieth-century sea-level rise, this has not been done for the other contributors or total global mean sea-level change (GMSLC). Here, we evaluate the influence of greenhouse gases (GHGs), anthropogenic aerosols, natural radiative forcings and internal climate variability on sea-level contributions of ocean thermal expansion, glaciers, ice-sheet surface mass balance and total GMSLC. For each contribution, dedicated models are forced with results from the Coupled Model Intercomparison Project Phase 5 (CMIP5) climate model archive6. The sum of all included contributions explains 74 ± 22% (±2σ) of the observed GMSLC over the period 1900–2005. The natural radiative forcing makes essentially zero contribution over the twentieth century (2 ± 15% over the period 1900–2005), but combined with the response to past climatic variations explains 67 ± 23% of the observed rise before 1950 and only 9 ± 18% after 1970 (38 ± 12% over the period 1900–2005). In contrast, the anthropogenic forcing (primarily a balance between a positive sea-level contribution from GHGs and a partially offsetting component from anthropogenic aerosols) explains only 15 ± 55% of the observations before 1950, but increases to become the dominant contribution to sea-level rise after 1970 (69 ± 31%), reaching 72 ± 39% in 2000 (37 ± 38% over the period 1900–2005). [less ▲]

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See detailAnthropogenic impact on alluvial sedimentation rates during the last millennia in the Ardennes (Belgium)
Houbrechts, Geoffrey ULg; Notebaert, Bastiaan; Petit, François ULg et al

Conference (2014, February 03)

Alluvial deposits of numerous rivers in the Ardennes have been dated by using iron slag content and 14C. On the basis of these analyses, several periods of increased sediment deposition have been ... [more ▼]

Alluvial deposits of numerous rivers in the Ardennes have been dated by using iron slag content and 14C. On the basis of these analyses, several periods of increased sediment deposition have been identified. Before the first deforestations, rivers in this region developed multiple channels in alluvial forests (anabranching rivers), which are still distinguishable in the topography of many floodplains by means of LIDAR survey. Moreover, during this period, floodplains were not well-developed and probably very humid, which explains the presence of peat layers within the alluvial sequences. In the Amblève catchment, the first increased sedimentary deposition of the Holocene occurred during the Bronze Age, probably in relation to deforestation and first cropland agriculture in the area. Archaeological data indicate Roman occupation in parts of the catchment, and Roman Period colluvium has been found at one site. Several peat layers have been dated in the Lienne catchment to around 1000 BP and probably indicate very low anthropogenic pressure. From the 11th Century onwards, there was an increase in sedimentation, coinciding with a higher concentration of charcoal in alluvial deposits. In many catchments there is an important increase in the sedimentation at the end of the 14th century, which can be related to the development of numerous iron-working sites. Analyses of slag concentration produced in these sites allow us to reconstruct the evolution of the floodplain topography in relation to the periods of blast furnaces activity. Total sedimentation in the smaller valleys since the initiation of iron industries amounts 0.5 to 1.0 m, which is in most cases about 40% of the total sediment present in the floodplains and corresponds to a mean sedimentation rate ranging between 10 and 20 cm/century. Such values are explained by former agricultural practices and woodland clearance associated with the huge demand for charcoal by the iron industry. For instance, about 20 ha of forest were cleared for the yearly consumption of a refining forge or a blast furnace and more than three hundred iron factories existed in the Ardenne Massif between the 14th and the 19th century. [less ▲]

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See detailAnthropogenic impacts in North Poland over the last 1300 years -- A record of Pb, Zn, Cu, Ni and S in an ombrotrophic peat bog
De Vleeschouwer, François ULg; Fagel, Nathalie ULg; Cheburkin, Andriy et al

in Science of the Total Environment (2009)

Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb–Zn ores ... [more ▼]

Lead pollution history over Northern Poland was reconstructed for the last ca. 1300 years using the elemental and Pb isotope geochemistry of a dated Polish peat bog. The data show that Polish Pb–Zn ores and coal were the main sources of Pb, other heavy metals and S over Northern Poland up until the industrial revolution. After review of the potential mobility of each element, most of the historical interpretation was based on Pb and Pb isotopes, the other chemical elements (Zn, Cu, Ni, S) being considered secondary indicators of pollution. During the last century, leaded gasoline also contributed to anthropogenic Pb pollution over Poland. Coal and Pb–Zn ores, however, remained important sources of pollution in Eastern European countries during the last 50 years, as demonstrated by a high 206Pb/207Pb ratio (1.153)relative to that of Western Europe (ca. 1.10). The Pb data for the last century were also in good agreement with modelled Pb inventories over Poland and the Baltic region. [less ▲]

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See detailAnthropogenic landscape change: synthesis of the concepts and quantification methods
Andre, Marie ULg; Vranken, Isabelle ULg; Mahy, Grégory ULg et al

Conference (2015, August 26)

Anthropogenic disturbances impact the whole biosphere, at least indirectly, and are of major concern in various disciplines and policies. To tackle it, most studies, specific to their thematic, create ... [more ▼]

Anthropogenic disturbances impact the whole biosphere, at least indirectly, and are of major concern in various disciplines and policies. To tackle it, most studies, specific to their thematic, create their own reference framework without connection with related purposes in other disciplines. This results in a plethora of terms and concepts that in turn impedes addressing that issue on a comprehensive way as well as complementarity between studies. Here, we clarify and synthesize the most frequently employed terms to characterise human impact on the environment (anthropisation, naturalness, hemeroby, novel ecosystem, analogous ecosystem, climax, etc.), their synonyms, the nuances and relationships between each of them, as well as the concepts used to designate the responses given by humans to environmental disturbances (restoration, management, conservation). We go on reviewing the methods used to assess anthropogenic changes, exploring different branches of ecology and geography. The strengths and weaknesses of the existing approaches are then used as a basis to develop a new analytical framework: we propose an action-oriented type of naturalness, and we develop a general methodology to quantify landscape anthropisation. Our methodology combines object-oriented and gradient analyses. Moreover, it is based on the assessment of ecosystem disturbance, landscape configuration and dynamics as well as on easily acquired data sets. Our integrated approach of the concern could be at the basis of land planning, environmental restoration and management practices as well as policies. [less ▲]

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