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See detailRegional forest inventory in Belgium : main aspects of the data processing system
Rondeux, Jacques ULg; Toussaint, André ULg

in Symposium National Forstinventuren in Europa (1987)

L'objectif principal de l'inventaire forestier réalisé de 1980 à 1983 dans le Sud de la Belgique était non seulement de récolter des informations de base destinées à tracer les grandes lignes d'une ... [more ▼]

L'objectif principal de l'inventaire forestier réalisé de 1980 à 1983 dans le Sud de la Belgique était non seulement de récolter des informations de base destinées à tracer les grandes lignes d'une politique forestière, mais aussi de fournir rapidement une idée aussi objective que possible de l'état actuel des surfaces occupées par la forêt, des volumes sur pied et de la répartition des essences. L'inventaire mis en oeuvre est un inventaire par échantillonnage systématique qui s'appuie sur plus de 11.000 placettes temporaires situées aux intersections de mailles rectangulaires de 1.000 m x 500 m. Les données récoltées à chaque point de sondage concernent, de manière très générale, la situation géographique et administrative du lieu, ainsi que la caractérisation sylvicole, dendrométrique et écologique des peuplements. En vue de traiter et d'exploiter la masse considérable de données et d'informations rassemblées, nous avons élaboré une base de données permanente et modulaire, c'est-à-dire comportant plusieurs fichiers interconnectables et hiérarchisés, selon les cas. Cette banque est gérée et exploitée par un système informatique caractérisé par une grande souplesse en vue d'une utilisation aussi aisée que possible des logiciels existants par un nombre élevé d'utilisateurs dont le bagage informatique est limité ou qui ne sont pas spécialement familiarisés avec les techniques du traitement électronique des informations. [less ▲]

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See detailA Regional Inventory and Monitoring Setup to Evaluate Bark Peeling Damage by Red Deer (Cervus Elaphus) in Coniferous Plantations in Southern Belgium
Gheysen, Thibaut; Brostaux, Yves ULg; Hebert, Jacques ULg et al

in Environmental Monitoring & Assessment (2010)

Bark peeling by red deer (Cervus elaphus L.) has become a serious issue for productive forests in western Europe. The damage is particularly severe on species such as spruce, as these become vulnerable to ... [more ▼]

Bark peeling by red deer (Cervus elaphus L.) has become a serious issue for productive forests in western Europe. The damage is particularly severe on species such as spruce, as these become vulnerable to fungus attacks that result in considerably depreciated timber. This article presents a monitoring setup for recent bark peeling damage in spruce plantings in Wallonia (southern part of Belgium). This setup implies to collect data annually from a survey involving cluster sampling. It has been employed since 2004 in coniferous stands amounting to 165,000 ha of land, where Norway spruce is the predominant species. The study area was divided into blocks delineated along features preventing deer migrations. A set of indicators was computed either at the whole study area level or at block level. The resulting set of indicators enabled forest managers to follow up debarking intensity in productive forests. Additional analyses were carried out in order to assess the relationship between the social position of trees in the stand and the debarking probability on the one hand, and the relationship between the variation in damage magnitude and seasonality, namely summer versus winter, on the other hand. [less ▲]

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See detailRegional mapping of pedogeochemical background in Southern Belgium: Combining grid-survey measurements with existing maps of the physical environment.
Colinet, Gilles ULg; Bock, Laurent ULg

Conference (2009)

Among natural factors driving the soil content in metallic trace elements (MTE), the geochemical background is often deemed as a sound base for the detection of contaminations. Numerous studies have shown ... [more ▼]

Among natural factors driving the soil content in metallic trace elements (MTE), the geochemical background is often deemed as a sound base for the detection of contaminations. Numerous studies have shown the difficulties to take into account the multi-dimensionnality of the spatial variability of most soil properties. As far as a detailed soil map is available for Belgium, the relevance of its information was investigated at various spatial scales in the Walloon Region (Southern Belgium), from the plot to the entire region, to evaluate the feasibility of a multi-scale mapping of geochemical background. The soil properties of 410 plots from the regional forest soil monitoring and the relationships with informations related to the physical environment (lithology, soil types...) were investigated through multivariate statistical analysis. Some processes of integration of point measurements and qualitative information were also explored. At the regional scale, some long-range spatial structures could be identified. These result mainly from the geological structure of the Walloon region, where the lithological zonation is rather clearly marked. The soil map (texture and nature of stone charge) appears relevant at that scale too but does need a generalization process and fails however to differenciate the intra-type soil spatial variability. [less ▲]

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See detailRegional model of the Somes-Szamos aquifer (RO-HU)
Drobot, Radu; Jianu, Marilena; Sirbu, Nicolai et al

in Hidrotehnica (2004), 49(9-10), 58-66

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See detailRegional modelling of the biogeochemical cycles in the Western Mediterranean (EROS 2000)
Djenidi, Salim ULg; Martin, J. M.; Beckers, Jean-Marie ULg et al

in Barthel, K. G.; Bohle-Carbonell, C.; Weydert, M. (Eds.) Marine Sciences and technologies (1993)

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See detailRegional organisation of brain activity during paradoxical sleep (PS)
Maquet, Pierre ULg; Ruby, P.; Schwartz, S. et al

in Archives Italiennes de Biologie (2004), 142(4), 413-419

Human brain function is regionally organised during paradoxical sleep (PS) in a very different way than during wakefulness or slow wave sleep. The important activity in the pons and in the limbic ... [more ▼]

Human brain function is regionally organised during paradoxical sleep (PS) in a very different way than during wakefulness or slow wave sleep. The important activity in the pons and in the limbic/paralimbic areas constitutes the key feature of the functional neuroanatomy of PS, together with a relative quiescence of prefrontal and parietal associative cortices. Two questions are still outstanding. What neurocognitive and neurophysiological mechanisms may explain this original organization of brain function during PS? How the pattern of regional brain function may relate to dream content? Although some clues are already available, the experimental answer to both questions is still pending. [less ▲]

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See detailRegional scale flow and transport modelling for the management of groundwater and surface water bodies in the framework of the EU Water Directive
Leroy, Mathieu; Orban, Philippe ULg; Brouyère, Serge ULg et al

Conference (2011, May 02)

The Water Framework Directive requires from EU member states to manage water resources at the scale of surface water and groundwater bodies in a sustainable way, without altering the different functions ... [more ▼]

The Water Framework Directive requires from EU member states to manage water resources at the scale of surface water and groundwater bodies in a sustainable way, without altering the different functions provided by the system in natural conditions. Efficient management also requires qualitative tools to assess the evolution of water quality regarding the activities performed in the area of interest. In this context, the objective is to discuss the needs in terms of groundwater flow and transport modelling as a support to the Water Framework Directive and to present a methodological and numerical approach that fits with these requirements. Different variably-saturated models have been implemented for selected case studies ranging between 500 and 1700 km² in the Walloon Region of Belgium. The implementation of such models is challenging because of the scale and the processes that have to be simulated. However, when calibrated and used adequately, they are able to deliver most information required, such as the estimation and evolution with time of groundwater reserves, the calculation of different indicators on groundwater replenishment and exploitation, the base flow to rivers and surface water bodies, under different stress conditions such as pumping, rainfall and climate change. They are also used for the evaluation of regional groundwater quality status and for contaminant trend assessment (e.g. nitrate) under different alternative management scenarios and mitigation measures that could be implemented in the future. This study illustrates perfectly the efficiency and usefulness of regional scale groundwater flow and transport modelling as a tool for the management of groundwater bodies. [less ▲]

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See detailRegional scale groundwater flow and transport modelling: from conceptual challenges to pragmatic numerical solutions
Wildemeersch, Samuel ULg; Goderniaux, Pascal ULg; Leroy, Mathieu et al

Conference (2011, July 05)

National and international regulations require the management of groundwater resources at the regional scale, considering the physical limits of hydrogeological systems. Physically-based, spatially ... [more ▼]

National and international regulations require the management of groundwater resources at the regional scale, considering the physical limits of hydrogeological systems. Physically-based, spatially-distributed groundwater flow and transport models allow representing in a realistic and reliable way the dynamics of regional groundwater systems and processes and accounting for negative or positive feedbacks induced by a changed stress factors or particular measures set up in the basin such as increase in pumping, use of fertilizers or artificial recharge. Such models are complex and their development and implementation are challenging for several reasons related to numerical difficulties but also to data acquisition and management, conceptualization, calibration and validation. Variably-saturated, regional flow and transport models have been developed using two finite element simulators SUFT3D and HydroGeoSphere specifically suited to regional-scale applications. A complex synthetic case has been used as a reference model to test the impact on predictions made and computing times of various conceptual and technical choices such as spatial and time discretization, simplified unsaturated laws or boundary conditions. Real cases have been developed for regional groundwater bodies (from 500 to 1700 km²) to deliver relevant information such as the estimation and evolution with time of groundwater reserves, under different stress conditions such as climate changes and for the evaluation of regional groundwater quality status and nitrate trend assessment under alternative management scenarios and mitigation measures. Results provide guidelines for the conceptualisation, the calibration and the use of regional-scale groundwater flow and transport models for decision making. [less ▲]

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See detailRegional transport modelling for nitrate trend assessment and forecasting in a chalk aquifer
Orban, Philippe ULg; Brouyère, Serge ULg; Batlle-Aguilar, Jordi et al

in Journal of Contaminant Hydrology (2010), 118

Regional degradation of groundwater resources by nitrate has become one of the main challenges for water managers worldwide. Regulations have been defined to reverse observed nitrate trends in groundwater ... [more ▼]

Regional degradation of groundwater resources by nitrate has become one of the main challenges for water managers worldwide. Regulations have been defined to reverse observed nitrate trends in groundwater bodies, such as the Water Framework Directive and the Groundwater Daughter Directive in the European Union. In such a context, one of the main challenges remains to develop efficient approaches for groundwater quality assessment at regional scale, including quantitative numerical modelling, as a decision support for groundwater management. A new approach combining the use of environmental tracers and the innovative ‘Hybrid Finite Element Mixing Cell’ (HFEMC) modelling technique is developed to study and forecast the groundwater quality at the regional scale, with an application to a regional chalk aquifer in the Geer basin in Belgium. Tritium data and nitrate time series are used to produce a conceptual model for regional groundwater flow and contaminant transport in the combined unsaturated and saturated zones of the chalk aquifer. This shows that the spatial distribution of the contamination in the Geer basin is essentially linked to the hydrodynamic conditions prevailing in the basin, more precisely to groundwater age and mixing and not to the spatial patterns of land use or local hydrodispersive processes. A three-dimensional regional scale groundwater flow and solute transport model is developed. It is able to reproduce the spatial patterns of tritium and nitrate and the observed nitrate trends in the chalk aquifer and it is used to predict the evolution of nitrate concentrations in the basin. The modelling application shows that the global inertia of groundwater quality is strong in the basin and trend reversal is not expected to occur before the 2015 deadline fixed by the European Water Framework Directive. The expected time required for trend reversal ranges between 5 and more than 50 years, depending on the location in the basin and the expected reduction in nitrate application. To reach a good chemical status, nitrate concentrations in the infiltrating water should be reduced as soon as possible below 50mg/l; however, even in that case, more than 50 years is needed to fully reverse upward trends. [less ▲]

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See detailA regional travel model for predicting the number of visitors in forests: application to the Walloon region
Colson, Vincent ULg; Lejeune, Philippe ULg

in Raschi, A.; Trampetti, S. (Eds.) Management for protection and sustainable development (2008)

The Walloon forests are visited by local people and tourists but the importance of forest recreation is very different from one part of the Region to another. As it was particularly difficult to obtain ... [more ▼]

The Walloon forests are visited by local people and tourists but the importance of forest recreation is very different from one part of the Region to another. As it was particularly difficult to obtain quantified information by counting, a model has been built by GIS and taking results from different surveys (telephone survey and face-to-face interviews) into account. This model makes the distinction between local visitors and one-day tourists coming from the neighbouring regions (in a buffer zone of 50 km). A decay curve based on travel time is used for predicting the number of visits throughout all Walloon forests from each departure point. An attraction function is added to the model to attribute each visit to a woodland and different scenarios have been tested to obtain a distribution of people by regions of provenance as similar as the results of surveys. At a regional level, this model is a good alternative to counting and gives a good overview of the forests for which recreation activities are more relevant and have to be taken into account in forest management plans. [less ▲]

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See detailRegional urban groundwater body risk assessment of contaminants using remotely sensed multi-resolution land-cover data
Batelaan, Okke; Dujardin, Juliette; Jamin, Pierre ULg et al

Conference (2013, September 15)

Contaminated sites are often the result of past relatively anarchic economical and industrial development. The last decades stakeholders are more aware of the risks posed by these sites. Within the Frac ... [more ▼]

Contaminated sites are often the result of past relatively anarchic economical and industrial development. The last decades stakeholders are more aware of the risks posed by these sites. Within the Frac-Weco project an integrated framework for the assessment, at regional scale, of the risks posed by these contaminated sites on water resources and ecosystems has been developed. The methodology is based on the calculation of contaminant fluxes reaching the receptors providing a way of estimating the level of exposure/degradation of these receptors at the groundwater body scale. The most important contamination problems at regional scale are located around old urban and industrialized areas. The land-cover distribution in these zones is of prime importance because it determines the spatial variation of groundwater recharge, which is the main vector of contaminant leaching from soil surface to groundwater. To obtain detailed information about land cover for groundwater recharge modeling, a stratified satellite image classification approach was adopted combining land-cover mapping at pixel level for the studied area as a whole with sub-pixel estimation of imperviousness within built-up zones. The obtained land-cover data is used as an input in the WetSpass model to simulate groundwater recharge at high resolution in spatially complex urban areas. In the next step the simulated groundwater recharge is used as an input in a regional scale groundwater flow and transport model simulating contaminant dispersion through the aquifer. Modeling results are further used to calculate a quality index for the whole groundwater body based on threshold values defined specifically for each contaminant. The approach proposed has been applied on the RWM073 groundwater body corresponding to the alluvial deposits of the Meuse River, Liège (Belgium). The high-resolution groundwater recharge estimations obtained by integrating remote sensing in the modeling procedure allow a better identification of the potential sources of contaminants and enable a proper quantification of total fluxes of contaminants from brownfields into the groundwater. The developed framework for regional risk assessment results in a global quality indicator for the groundwater body which can be used as input for decision-making. [less ▲]

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See detailRegional variability in mottled subclinical melanoderma in the elderly.
Petit, Ludivine; Fogouang, L.; Uhoda, Isabelle et al

in Experimental Gerontology (2003), 38(3), 327-31

The density in melanin chromatophores becomes heterogeneous in the epidermis during the early events of photoaging. Little is known about the regional variability in the resulting mottled skin appearance ... [more ▼]

The density in melanin chromatophores becomes heterogeneous in the epidermis during the early events of photoaging. Little is known about the regional variability in the resulting mottled skin appearance on the sun-exposed parts of the body in the elderly. The relationship between these features and the dermal atrophy related to aging is also an area ripe for study. The aim of the present study was to objectively assess and compare such aspects of photoaging in older subjects. A computer-assisted video camera equipped with an internal ultraviolet-emitting unit (Visioscan) was used in combination with image analysis to quantify the infraclinical mottling of the skin on the forehead, neck and dorsal forearm. A Densi Score device served to assess the dermal atrophy by rating the skin folding capacity. A mottled subclinical melanoderma was disclosed on the three evaluation sites in all subjects irrespective of their phototypes. Three main patterns were identified corresponding to regular perifollicular dots, streaky macules along shallow wrinkles and unevenly shaped macules in the interfollicular area. The extent in melanoderma was larger on the forehead than on the neck and forearm. The age after 60 years did not influence the severity of mottled melanoderma, but clearly altered the skin folding capacity. The greatest inter-individual differences in mottled melanoderma were found in phototype II subjects. In conclusion, infraclinical mottled melanoderma is present in all individuals after 60 years of age. This type of epidermal photoaging does not appear to be influenced in older ages. By contrast, skin laxity due to dermal aging continues to progress beyond the age of 60 years. [less ▲]

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See detailRegional variability in stratum corneum reactivity to antiseptic formulations.
Quatresooz, Pascale ULg; Xhauflaire, Emmanuelle ULg; Pierard, Claudine ULg et al

in Contact Dermatitis (2007), 56(5), 271-3

Skin does not react in an identical way to the action of chemicals over all anatomic sites. Accordingly, distinct regional differences have been described in relation to irritancy. The present study ... [more ▼]

Skin does not react in an identical way to the action of chemicals over all anatomic sites. Accordingly, distinct regional differences have been described in relation to irritancy. The present study assesses the regional variations of stratum corneum (SC) reactivity to 3 proprietary antiseptic solutions (povidone iodine (PVP-I), 70 mg/ml and 100 mg/ml, and chlorhexidine digluconate 50 mg/ml) using the corneoxenometry (CXM) bioassay. SC was harvested from the volar forearm, the forehead and the back in 30 young adults. Each SC sample was covered by one of the neat test product or deionized water for 2 hr at 20 degrees C. The intrinsic staining property of each antiseptic on SC was assessed by reflectance colorimetry. For the CXM bioassay, samples were then stained by a toluidine blue-basic fuschin solution in order to show protein denaturation induced by the test products. The colorimetric index of mildness (CIM = L*- Chroma C*) was measured by colorimetry. Data show that PVP-I 100 mg/ml was the least reactive antiseptic to the SC. It was significantly milder than the 2 other antiseptics. [less ▲]

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See detailRegional variations of the otter (Lutra lutra) diet in western France
Libois, Roland ULg; Rosoux, René; Delooz, Etienne

Poster (1991, March)

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See detailRegional, aber standardkompatibel. Regionale Umgangssprache im Rheinland
Möller, Robert ULg

in Valentin, Jean-Marie (Ed.) Akten des XI. Internationalen Germanistenkongresses Paris 2005. "Germanistik im Konflikt der Kulturen.". Band 4: Empirische Grundlagen moderner Grammatikforschung [...]. (2008)

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See detailRegional, Interregional and Global Arrangements and Multilateral Organizations
Santander, Sébastian ULg

in Telò, Mario (Ed.) Globalization, Multilateralism, Europe. Towards a Better Global Governance? (2014)

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See detailRegional, Interregional and Global Arrangements and Organizations
Santander, Sébastian ULg

in Telò, Mario (Ed.) International Relations: A European Perspective (2009)

Cet contribution trace un large panorama des accords régionaux et interrégionaux et revient aussi sur les organismes multilatéraux

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See detailRegional-based typology of the main fungal diseases affecting winter wheat in the Grand-Duchy of Luxembourg
El Jarroudi, Moussa ULg; Giraud, Frédéric; Delfosse, Philippe et al

in Phytopathology (2011), 101

Despite its small territory size, the Grand-Duchy of Luxembourg (GDL) has several microclimates that result in a variability of disease severity between the South (Gutland) and the North (Oesling ... [more ▼]

Despite its small territory size, the Grand-Duchy of Luxembourg (GDL) has several microclimates that result in a variability of disease severity between the South (Gutland) and the North (Oesling). Septoria leaf blotch disease of wheat is an important disease in the GDL. Over 2003–2009, the severity was strong in Gutland (51% on average over the last two upper leaves at the late milk growth stage) and low in the Oesling (16% for the same leaves). For the years 2006, 2008 and 2009, the disease severity was less than 6% in the Oesling while it exceeded 40% in the Gutland. The second fungal disease that has become economically important is the wheat leaf rust. Over the same period, the Gutland and the Oesling showed consistently the highest and lowest disease severity respectively. In 2003 and 2007, the Gutland showed the highest disease severity with 66% and 57% respectively, whereas the lowest severity (<1%) was observed in the Oesling. Another important disease is wheat powdery mildew. The 2003 and 2009 cropping seasons showed the highest disease severity with 15% and 40%, respectively, in the Oesling whereas less than 1% severity was registered in the Gutland. Fusarium head blight was also present in the eastern part of the Gutland showing the highest prevalence and severity in 2007 and 2008 (8.5% and 8.3% respectively). These prevalence and severity percentages were significantly higher compared to the Oesling (% prevalence % severity, p = 0.049 and p = 0.012, respectively, Tukey’s test). [less ▲]

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See detailRegional-based typology of the main fungal diseases affecting winter wheat.
El Jarroudi, Moussa ULg; Giraud, Frédéric; Delfosse, Philippe et al

Poster (2011, August 06)

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