Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailImpacts des mutations du commerce sur la hiérarchie des polarités commerciales, l’exemple de la Belgique
Merenne-Schoumaker, Bernadette ULg

in Hommes et Terres du Nord (1998), 1998(4), 217-224

Impact of the transformation of trade in the hierarchy of commercial polarities. The Belgian example. Starting with a vast survey of purchasing behaviour in Belgium (concerning 30 000 households), the ... [more ▼]

Impact of the transformation of trade in the hierarchy of commercial polarities. The Belgian example. Starting with a vast survey of purchasing behaviour in Belgium (concerning 30 000 households), the article analyses how the main Belgian commercial poles are classified in current and semi-current purchases. It also manages to understand what lead to changes, for example to the important alterations that occured in the periphery of the biggest urban areas, namely in terms of current purchases. As opposed to what has sometimes been claimed, everything leads to the fact that the hierarchy of poles still exists. It mainly concerns semi-current purchase, however. On the other hand, if it appears that urban centers are still the main trading poles, the classification based on the volume of polarised population points up several shopping centers. This shows then the increasingly important part played by the new planified polarities. [less ▲]

Detailed reference viewed: 88 (3 ULg)
Full Text
Peer Reviewed
See detailImpacts des récentes variations pluviométriques sur le droit du sol, l’accès a l’eau et l’agriculture en Mauritanie : l’exemple du lac de Mâle
Gassani, Jean; De Longueville, Florence ULg; Gemenne, François ULg et al

in Camberlin, Pierre; Richard, Yves (Eds.) Actes du 27e Colloque International de l'Association Internationale de Climatologie (2014)

The Islamic Republic of Mauritania is at a socio-political crossroads in its history. Environmental crises coupled with the transformation of economic activities and population pressures disrupt social ... [more ▼]

The Islamic Republic of Mauritania is at a socio-political crossroads in its history. Environmental crises coupled with the transformation of economic activities and population pressures disrupt social structures of the country. The drought that began in 1970 has transformed the nomadic lifestyle, forcing them to settle. This deeply changed tribes’ perception access to land and water resources, and has led to increased pressure on the Haratines (former black slaves) in agricultural production. With the release of human rights, the enactment of a land law, and taking into account the Sharia, former slaves claimed their ownership of the land they cultivated. The refusal of the latter to access their application, the Haratines headed for land undeveloped and interfered in the customary practice of the management of water catchments. The latent conflict escalated into open in the watershed of Lake Mâle. Today, the situation does not improve since the political will collides with local tribal authorities. [less ▲]

Detailed reference viewed: 41 (7 ULg)
Full Text
Peer Reviewed
See detailImpacts du changement climatique sur l’hydrologie et la gestion des ressources en eau du bassin de la Meuse : une synthèse
Bauwens, Alexandra ULg; Sohier, Catherine ULg; Degré, Aurore ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2013), 17(1), 76-86

Detailed reference viewed: 79 (20 ULg)
Full Text
Peer Reviewed
See detailImpacts écologiques des aménagements touristiques sur le littoral de Saïdia, Maroc oriental
Boumeaza, Taieb; Sbai, Abdelkader; Salmon, Marc ULg et al

in Revue géographique des pays méditerranéens (2010), 115

Le littoral de Saïdia est connu depuis fort longtemps pour sa plage naturelle dont l’évolution est dépendante d’une part des alluvions apportées par la Moulouya qui avait permis l’engraissement de ce ... [more ▼]

Le littoral de Saïdia est connu depuis fort longtemps pour sa plage naturelle dont l’évolution est dépendante d’une part des alluvions apportées par la Moulouya qui avait permis l’engraissement de ce littoral, créant un delta avant la construction des barrages et d’autre part des courants marins responsables de la redistribution des sables le long de la côte. Actuellement, ce littoral subit une pression anthropique aggravée, due à la construction d’une station balnéaire et d’une marina à proximité immédiate de la côte. Ceci a provoqué un déséquilibre du système dunaire et a bouleversé les mécanismes d’évolution du littoral, avec des impacts directs sur l’environnement écologique de la zone humide de la Moulouya. [less ▲]

Detailed reference viewed: 13 (0 ULg)
Full Text
See detailImpacts environnementaux des unités de biométhanisation
Nicolas, Jacques ULg; Neyrinck, Roland; Cerisier, Christophe et al

Report (2012)

The report presents a study conducted in the frame of a European Interreg project. The role of the research group was to investigate the possible environmental impacts of on-farm biogas production from ... [more ▼]

The report presents a study conducted in the frame of a European Interreg project. The role of the research group was to investigate the possible environmental impacts of on-farm biogas production from anaerobic reactors. The odour impact was chiefly analysed with the aim of assessing the odour generated by farms equipped for biogas production compared to classical farms. Also, the odour levels in the head space of various materials, either prior or after methanation were compared, using different methods. [less ▲]

Detailed reference viewed: 45 (13 ULg)
See detailImpacts of (NH4)2SO4 deposition on Norway spruce (Picea abies [L.] Karst) and Scots pine (Pinus sylvestris L.) fine roots
Carnol, Monique ULg; Zoomer, Rik; Berg, Matty et al

Conference (1998, September)

The increased inorganic nitrogen (N) deposition in the last decades has become a major concern for the health of forests. In forest ecosystem, where N might no longer be limiting to primary production ... [more ▼]

The increased inorganic nitrogen (N) deposition in the last decades has become a major concern for the health of forests. In forest ecosystem, where N might no longer be limiting to primary production, the excess N is thought to be related to forest decline and a concept of ‘N saturation ‘ has been developed. In particular, N, in the form of NH4, in excess to plant and microbial demands could lead to soil acidification if nitrified in the soil and leached, causing loss of base cations or mobilisation of phytotoxic aluminium. As part of the CORE project (CEC), investigating nutrient dynamics in European coniferous forest soils, we studied the effects of continuously increased (NH4)2SO4 deposition and soil characteristics on Norway spruce (Picea abies [L.] Karst) and Scots pine (Pinus sylvestris L.) fine root biomass, vitality and chemistry with an ingrowth core technique. The same experiment was performed in a Norway spruce stand on clay soil (Grizedale, UK) and a Scots pine stand on sandy soil (Wekerom, NL), using soil from each of the two sites. Root-free ingrowth cores reproduced organic and mineral soil horizons to 15 cm depth. They were covered to exclude native throughfall and watered every 2 weeks with throughfall or throughfall with (NH4)2SO4 added to increase deposition by 75 kg ha-1 a-1 NH4+-N. The ingrowth cores were sampled after 19 months, divided into layers, roots washed and analysed for biomass, necromass, root length, root tip number (RTN), root tip vitality and fine root chemistry. A previous field experiment had shown high soil solution Al concentrations at both sites, and an increase in NO3- and Al concentrations in response to increased (NH4)2SO4 deposition at the Grizedale site. The effects of high (NH4)2SO4 deposition depended on tree species, soil type and soil horizon. For Norway spruce, (NH4)2SO4 deposition did not result in any significant changes in root growth or vitality when growing into the native clay soil. However, when growing into the sandy soil, RTN and the proportion of dead roots were increased by N deposition. Norway spruce fine root N content was also increased in the organic horizon of both soil types. For Scots pine, (NH4)2SO4 treatment caused increased fine root Al content and a decreased Mg/Al ratio in the mineral layer of the sandy soil, with opposite effects in the clay soil. This (NH4)2SO4 treatment effect in the sandy soil for Scots pine was the only indication of a potential adverse effect of (NH4)2SO4 deposition on fine roots. Further results demonstrated the dominant importance of inherent soil characteristics and the stratification into soil horizons on fine root growth and chemical composition. For example, a negative correlation between root biomass and fine root Al content was established for Norway spruce. [less ▲]

Detailed reference viewed: 18 (0 ULg)
Full Text
Peer Reviewed
See detailImpacts of (NH4)2SO4 deposition on Norway spruce (Picea abies [L.] Karst) roots
Carnol, Monique ULg; Cudlin, Pavel; Ineson, Phil

in Water, Air & Soil Pollution (1999), 116

The effects of enhanced (NH4)(2)SO4 (NS) deposition on Norway spruce (Picea abies [L.] Karst) fine root biomass, vitality and chemistry were investigated using root-free in-growth cores reproducing native ... [more ▼]

The effects of enhanced (NH4)(2)SO4 (NS) deposition on Norway spruce (Picea abies [L.] Karst) fine root biomass, vitality and chemistry were investigated using root-free in-growth cores reproducing native organic and mineral soil horizons. The cores were covered and watered every 2 weeks with native throughfall or throughfall supplemented with NS to increase deposition by 75 kg ha(-1) a(-1) NH4+-N (86 kg ha(-1) a(-1) SO42--S). The in-growth cores were sampled after 19 months and assessed for root biomass, necromass, length, tip number, tip vitality and fine root chemistry. Root biomass and fine root aluminium (Al) concentration were negatively correlated, but NS deposition had no effect on root growth or root tip vitality. NS deposition caused increased fine root nitrogen (N) concentrations in the organic horizon and increased Calcium (Ca) concentrations in the mineral horizon. Fine root biomass was higher in the organic horizon, where fine root Al and potassium (K) concentrations were lower and Ca concentrations higher than in the mineral horizon. Results highlighted the importance of soil stratification on fine root growth and chemical composition. [less ▲]

Detailed reference viewed: 17 (1 ULg)
See detailImpacts of a recent Streptococcus outbreak in a commensal population of long-tailed macaques (Macaca fascicularis) in Bali, Indonesia
Brotcorne, Fany ULg; Wandia, I. Nengah; Beudels-Jamar, Roseline et al

Conference (2013, September 11)

The quest for coexistence between humans and primates requires an extensive analysis of the impacts of the growing commensalism phenomenon. In South-east Asia, the long-tailed macaque adapts successfully ... [more ▼]

The quest for coexistence between humans and primates requires an extensive analysis of the impacts of the growing commensalism phenomenon. In South-east Asia, the long-tailed macaque adapts successfully to anthropogenic habitats. The low predation pressure in zones of human-macaque interface and the inclusion of human food in macaques’ diet can lead to local overpopulation. On the other hand, the risk of epidemic disease simultaneously increases with high primate density and proximity with human vectors. Data presented here represent 25 years-population dynamics of a commensal-living population of macaques in Ubud Monkey Forest (Indonesia). Over this period, the population experienced a dramatic growth with an average 11% annual increase rate. In June 2012, we counted 615 individuals divided in 5 groups with a very high density of 61 macaques per hectare. However, two Streptococcus outbreaks have also been reported over the same period, temporarily limiting the steep positive demographic trend of this population. The first epidemic episode appeared in 1994 and the second in July 2012, the last one resulting in 14% mortality in 3 out of 5 groups of the population (563 macaques in October 2012). The comparison between the pre- and post-outbreak periods in 2011-2012 shows changes in macaques’ ranging and behaviour. After the outbreak, the affected groups used smaller and more peripheral home ranges, while the non-affected groups centred their home ranges on the human provisioning places. Besides anthropic factors promoting population growth, epidemic diseases play a significant role in shaping the dynamics and behaviour of this synanthropic population and could have important implications in the future both in terms of management and local conservation status. [less ▲]

Detailed reference viewed: 35 (6 ULg)
Full Text
See detailImpacts of a unicellular mechanism on network behaviors
Dethier, Julie ULg; Drion, Guillaume; Franci, Alessio et al

Conference (2013, March 26)

Parkinson’s disease (PD) is a neurodegenerative disorder af- fecting the basal ganglia (BG), a set of small subcortical nervous system nuclei. The hallmark of the disease is a dopaminergic denervation of ... [more ▼]

Parkinson’s disease (PD) is a neurodegenerative disorder af- fecting the basal ganglia (BG), a set of small subcortical nervous system nuclei. The hallmark of the disease is a dopaminergic denervation of the striatum—the input stage of the BG—altering information patterns along movement- related ganglia-mediated pathways in the brain. Severe mo- tor symptoms result from the pathological state: tremor at rest, bradykinesia—the slowness and impaired scaling of voluntary movement—and akinesia—the poverty of volun- tary movements. It is still unclear how dopamine depletion causes those motor symptoms. Experimental studies have shown that abnormally synchronized oscillatory activities— rhythmic bursting activity at the unicellular level and beta frequency band (from 8 to 30Hz) oscillations at the network level—emerge in PD at multiple levels of the BG-cortical loops and correlate with motor symptoms. The mechanisms underlying these pathological beta oscillations remain elu- sive. We propose that a cellular mechanism generates burst- ing activities and beta band oscillations at the network level. [less ▲]

Detailed reference viewed: 67 (11 ULg)
See detailImpacts of alien invasive plants on soil and ecosystem processes in Belgium: lessons from a multispecies approach
Dassonville, Nicolas; Vanderhoeven, SONIA ULg; Domken, Sylvie et al

in Wilcox, C. P.; Turpin, R. B. (Eds.) Invasive Species:detection, Impact and Control (2008)

Detailed reference viewed: 46 (3 ULg)
Full Text
Peer Reviewed
See detailImpacts of alien invasive plants on soil nutrients are correlated with initial site conditions in NW Europe
Dassonville, Nicolas; Vanderhoeven, SONIA ULg; Vanparys, Valerie et al

in Oecologia (2008), 157(1), 131-140

Alien invasive plants are capable of modifying ecosystem function. However, it is difficult to make generalisations because impacts often appear to be species- and site-specific. In this study, we ... [more ▼]

Alien invasive plants are capable of modifying ecosystem function. However, it is difficult to make generalisations because impacts often appear to be species- and site-specific. In this study, we examined the impacts of seven highly invasive plant species in NW Europe (Fallopia japonica, Heracleum mantegazzianum, Impatiens glandulifera, Prunus serotina, Rosa rugosa, Senecio inaequidens, Solidago gigantea) on nutrient pools in the topsoil and the standing biomass. We tested if the impacts follow predictable patterns, across species and sites or, alternatively, if they are entirely idiosyncratic. To that end, we compared invaded and adjacent uninvaded plots in a total of 36 sites with widely divergent soil chemistry and vegetation composition. For all species, invaded plots had increased aboveground biomass and nutrient stocks in standing biomass compared to uninvaded vegetation. This suggests that enhanced nutrient uptake may be a key trait of highly invasive plant species. The magnitude and direction of the impact on topsoil chemical properties were strongly site-specific. A striking finding is that the direction of change in soil properties followed a predictable pattern. Thus, strong positive impacts (higher topsoil nutrient concentrations in invaded plots compared to uninvaded ones) were most often found in sites with initially low nutrient concentrations in the topsoil, while negative impacts were generally found under the opposite conditions. This pattern was significant for potassium, magnesium, phosphorus, manganese and nitrogen. The particular site-specific pattern in the impacts that we observed provides the first evidence that alien invasive species may contribute to a homogenisation of soil conditions in invaded landscapes. [less ▲]

Detailed reference viewed: 55 (3 ULg)
See detailImpacts of androgenic and antiandrogenic substances on the freshwater pulmonate gastropod Lymnaea stagnalis
Giusti, Arnaud ULg; Lagadic, Laurent; Joaquim-Justo, Célia ULg et al

Poster (2010, May 23)

Knowledge on the impacts of endocrine disruptors on gastropods is scarce and their mechanism of action poorly understood especially the impacts of androgenic and antiandrogenic compounds. In this study ... [more ▼]

Knowledge on the impacts of endocrine disruptors on gastropods is scarce and their mechanism of action poorly understood especially the impacts of androgenic and antiandrogenic compounds. In this study effects of 5 androgenics and antiandrogenics endocrine disruptors were investigated on the reproduction and life traits of the freshwater pulmonate gastropod Lymnaea stagnalis. The chemicals tested were Tributyltin, Cyproterone acetate, Methyltestosterone, Vinclozolin and Fenitrothion. Tributyltin was used as androgenic positive control. The other compounds tested are androgenic and antiandrogenic compounds either steroids or non steroids. Adult snails were exposed to 3 concentrations of each chemical for 30 days. The size and reproductive organs development were monitored throughout exposure. The number of clutches, the number of eggs per clutch were assessed during the first 10 days. The clutches were kept individually in clear water except for the clutches of the eighth day which were divided in two. Half was kept individually in clear water and the other half was individually reared in contaminated water following the same exposure as their parents. The percentage of hatching per clutch of these clutches was measured. The development size, mortality, and development of reproductive organs of the juveniles were assessed until their first clutch was laid. [less ▲]

Detailed reference viewed: 24 (6 ULg)
Full Text
Peer Reviewed
See detailImpacts of earthworms on soil components and dynamics. A review
Lemtiri, Aboulkacem ULg; Colinet, Gilles ULg; Alabi, Taofic ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18

Earthworm populations are important decomposers contributing to aggregate formation and nutrient cycling processes involving nitrogen cycles, phosphorus and carbon. They are known to influence soil ... [more ▼]

Earthworm populations are important decomposers contributing to aggregate formation and nutrient cycling processes involving nitrogen cycles, phosphorus and carbon. They are known to influence soil fertility by participating to important processes in soil such as soil structure regulation and organic matter dynamics. Earthworms also modify the microbial communities through digestion, stimulation and dispersion in casts. Consequently, changes in the activities of earthworm communities, as a result of soil management practices, can also be used as indicators of soil fertility and quality. It is therefore important to understand how earthworm communities affect soil dynamics. This review adresses the current state of knowledge on earthworm’s impacts on soil structure and soil organic matter (carbon, nitrogen, and phosphorus) dynamics, with special emphasis on the effects of land management practices on earthworm communities. [less ▲]

Detailed reference viewed: 89 (4 ULg)
Full Text
See detailImpacts of elevated CO2 on net nitrification and on the community structure of ammonia oxidising bacteria
Malchair, Sandrine ULg; Carnol, Monique ULg

in Biodiversity: state, stakes and future; 7,8 & 9 April 2004, Louvain-la-Neuve, Belgium, Symposium, Programme, Abstracts, Participants (2004)

Detailed reference viewed: 7 (0 ULg)
Full Text
See detailImpacts of future floods and low flows on the economy in the Meuse basin
Sinaba, B; Döring, R; Kufeld, M et al

in Dewals, Benjamin; Fournier, Maïté (Eds.) Transboundary Water Management in a Changing Climate (2013)

Climate change in Western Europe is projected to result in more humid winters and drier summers. Further, the sverities of floods and low flows are assumed to increase in the future. The impacts of these ... [more ▼]

Climate change in Western Europe is projected to result in more humid winters and drier summers. Further, the sverities of floods and low flows are assumed to increase in the future. The impacts of these events could lead to adverse consequences on the economy. Given this framework, within the AMICE project, the impacts of future floods and low flow will be analyzed. A flood risk analysis in the Meuse basin is conducted taking into account future climate scenarios. Further, the impacts of future droughts and low flows are analyzed for the economic sectors energy production, agriculture and navigation. [less ▲]

Detailed reference viewed: 31 (9 ULg)
See detailImpacts of grinding media alloys composition on the flotation of mixed oxides-sulphides copper ores.
Jacques, Simon; Bastin, David ULg

Conference (2011)

While the influence of the grinding media alloy composition on the flotation performances of sulphide ores has been widely studied, its role in the flotation of mixed (oxide and sulphide) ores is poorly ... [more ▼]

While the influence of the grinding media alloy composition on the flotation performances of sulphide ores has been widely studied, its role in the flotation of mixed (oxide and sulphide) ores is poorly documented. For some deposits, the mixed ores zone is well developed and can be of great importance for the economics of a mining project. These ore types often present technical challenges for their beneficiation such as sulphides tarnishment, slimes generation, presence of hydrophobic gangue or presence of acid consuming gangue. This study highlights the importance of matching the right grinding media alloy to the mineralogy of the ore, particularly its degree of weathering and to the subsequent flotation scheme. Shifting the grinding media towards less electrochemically active alloys significantly enhanced the grade-recovery curves and the flotation kinetics of the sulphides fraction, particularly when high degrees of sulphides oxidation were induced within the orebody or during stockpiling. For ores with high acid consuming gangue and medium acid soluble copper content that require a preconcentration of the oxide fraction by flotation through activation by sulphidisation, the higher sulphides flotation rates achieved with the use of high chromium alloys limited the amount of sulphides entering the sulphidisation stages and led to a better selectivity between acid insoluble and acid soluble copper allowing better downstream extractive metallurgy performances. [less ▲]

Detailed reference viewed: 70 (8 ULg)