References of "Mahy, Grégory"
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See detailCopper tolerance of three Crotalaria species from southeastern D.R. Congo at the early development stage [Tolérance au cuivre de trois espèces de Crotalaria de l’Arc Cuprifère Katangais dans les premiers stades de croissance]
Boisson, Sylvain ULg; Le Stradic, Soizig ULg; Commans, M. et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2016), 20(2), 151-160

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus ... [more ▼]

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus. Researches about the relationship between these endangered plants and soil copper concentrations are critical in order to improve ex situ conservation methods in southeastern Democratic Republic of Congo (Katangan Copperbelt). Objectives. The aim of the study was to test the effect of copper on the germination and root elongation of three Crotalaria species naturally occurring along a natural copper gradient. The hypothesis is that copper concentrations have different effects on germination and root elongation according to the species of Crotalaria genus. Method. Three species were selected: Crotalaria cobalticola, Crotalaria peschiana and Crotalaria cornetii, occurring on soils with the highest to the lowest copper concentrations respectively. Germination and root elongation tests were performed in vitro (MS vitamin-enriched medium) in six copper mediums ranging from 0 to 125 μM Cu2+. Results. No significant differences in germination percentage were observed according to the copper concentrations. Crotalaria cornetii had the lowest germination percentage. Root elongation of C. peschiana did not differ with copper concentration, but root elongation of C. cobalticola was higher at the greatest copper concentration (125 μM Cu2+). Conclusions. Even if C. cobalticola presented better growth at highest Cu concentrations, it appeared that C. cobalticola and C. peschiana do not require copper for their early stages of development and could thus be conserved in non-contaminated substrate. Crotalaria cornetii seemed to present a physical seed dormancy. © 2016, FAC UNIV SCIENCES AGRONOMIQUES GEMBLOUX. All rights reserved. [less ▲]

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See detailFunctional traits are more variable at the intra- than inter-population level: a study of four calcareous dry-grassland plant species
Harzé, Mélanie ULg; Mahy, Grégory ULg; Monty, Arnaud ULg

in Tuexenia (2016), 36

The majority of studies investigating plant functional traits have used species average trait values, and assumed that average values were sufficiently representative of each species considered. Although ... [more ▼]

The majority of studies investigating plant functional traits have used species average trait values, and assumed that average values were sufficiently representative of each species considered. Although this approach has proven valuable in community ecology studies, plant functional traits can significant-ly vary at different scales, i.e. between but also within populations. The study of species functional trait variability can facilitate increasingly accurate studies in community ecology. Nevertheless, the current extent of within-site plant trait variability has been poorly addressed in the literature. Calcareous grass-lands are ecosystems well-suited to study plant trait variation at small spatial scales. Many species are present on heterogeneous calcareous sites, with significant differences in hydric status due to variations in soil depth, soil moisture, aspect, and slope. This study assesses the extent of intra-population func-tional trait variability and tests the hypothesis that this variability can be explained by within-site envi-ronmental heterogeneity. Three functional traits (SLA-specific leaf area, LDMC-leaf dry matter con-tent, and plant vegetative height) were assessed in three populations of four calcareous grassland spe-cies totalling 950 individuals. The heterogeneity in soil depth and potential direct incident radiation was also quantified and related to plant functional trait variability. The intra-population functional trait variability was compared to the inter-population variability of collected data and global inter-population variability data obtained from the worldwide TRY functional traits database. The results showed that SLA, LDMC, and plant height are characterized by considerable intra-population variation (SLA: 72–95%, LDMC: 78–100% and vegetative height: 70–94% of trait variability). The results also indicate higher plant height and larger SLA for individuals located in plots with deeper soils or lower potential direct incident radiation, on gentle slopes or north-facing slopes. Our findings additionally support the concept that higher plant height, higher SLA, and lower LDMC are related to higher availability of soil water. Individuals on shallow soils or in more exposed areas are better equipped to cope with environ-mental stress. Our results indicate plasticity or local adaptation in individuals to environmental hetero-geneity. This study suggests that detailed analyses involving plant functional traits require measure-ments in situ from a large number of individuals, as the degree of individual response strongly depends on an individual’s location and its micro-environmental conditions. Neglecting intra-population trait variability may be critical, as intraspecific variation can be very high at the population scale, and is likely to be driven by local environmental heterogeneity.javascript:$('next-but').click(); [less ▲]

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See detailPotential of copper-tolerant grasses to implement phytostabilisation strategies on polluted soils in South D. R. Congo: Poaceae candidates for phytostabilisation
Boisson, Sylvain ULg; Le Stradic, Soizig ULg; Collignon, Julien et al

in Environmental Science and Pollution Research (2016)

Phytostabilisation (i.e. using plants to immobilise contaminants) represents a well-known technology to hamper heavy metal spread across landscapes. In Katanga (D. R. Congo), Microchloa altera, a tolerant ... [more ▼]

Phytostabilisation (i.e. using plants to immobilise contaminants) represents a well-known technology to hamper heavy metal spread across landscapes. In Katanga (D. R. Congo), Microchloa altera, a tolerant grass from the copper hills, was recently identified as a candidate species to stabilise copper in the soil. More than 50 grasses compose this flora, which may be studied to implement phytostabilisation strategies. However, little is known about their phenology, tolerance, reproductive strategy or demography. The present study aims to characterize the other Poaceae that may be used in phytostabilisation purposes based on the following criteria: their ecological distribution, seed production at two times, abundance, soil coverage and the germination percentage of their seeds. We selected seven perennial Poaceae that occur on the copper hills. Their ecological distributions (i.e. species response curves) have been modelled along copper or cobalt gradients with generalized additive models using logic link based on 172 presence/absence samples on three sites. For other variables, a total of 69 quadrats (1 m2) were randomly placed across three sites and habitats. For each species, we compared the number of inflorescence-bearing stems (IBS) by plot, the percentage of cover, the number of seeds by IBS and the estimated number of seeds by plot between sites and habitat. Three species (Andropogon schirensis, Eragrostis racemosa and Loudetia simplex) were very interesting for phytostabilisation programs. They produced a large quantity of seeds and had the highest percentage of cover. However, A. schirensis and L. simplex presented significant variations in the number of seeds and the percentage of cover according to site. [less ▲]

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See detailEdaphic niches of metallophytes from southeastern Democratic Republic of Congo: implications for post-mining restoration
Boisson, Sylvain ULg; Monty, Arnaud ULg; Lebrun, Julie et al

in Journal for Nature Conservation (2016)

In southeastern D. R. Congo, about 550 metallophytes grow on soils with high copper and cobalt concentrations, 57 of which are endemics to these metalliferous environments. About 70% of those endemics are ... [more ▼]

In southeastern D. R. Congo, about 550 metallophytes grow on soils with high copper and cobalt concentrations, 57 of which are endemics to these metalliferous environments. About 70% of those endemics are considered threatened by destruction of habitats through mining activities. To provide guidelines for future restoration programs, the edaphic ecological niches of eight copper endemics were studied using a pragmatic sampling method adapted for urgent conservation needs. Niches were modelled using violin plot along Cu, Co and C:N gradients representing the two main independent edaphic gradients among nine edaphic variables (C, N, C:N, K, P, pH, Co, Cu, and Mn). Copper endemics presented distinct edaphic niches along the copper and cobalt gradients, but differentiation was lower along the C:N gradient. In addition, edaphic elements presented covariations among them and metalliferous soils had higher nutrient and element content compared to the non-metalliferous soils of the region dominated by the Miombo woodland. The complexity of the soil composition and the edaphic niches of copper endemics revealed an important challenge in the implementation of the species conservation and the habitat restoration strategies of post-mining sites. [less ▲]

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See detailCopper tolerance of three Crotalaria species from southeastern D.R. Congo at the early development stage
Boisson, Sylvain ULg; Le Stradic, Soizig ULg; Commans, Morgane et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2016), 20(2), 151-160

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus ... [more ▼]

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus. Researches about the relationship between these endangered plants and soil copper concentrations are critical in order to improve ex situ conservation methods in southeastern Democratic Republic of Congo (Katangan Copperbelt). Objectives. The aim of the study was to test the effect of copper on the germination and root elongation of three Crotalariaspecies naturally occurring along a natural copper gradient. The hypothesis is that copper concentrations have different effects on germination and root elongation according to the species of Crotalaria genus.Method. Three species were selected: Crotalaria cobalticola, Crotalaria peschiana and Crotalariacornetii, occurring on soils with the highest to the lowest copper concentrations respectively. Germination and root elongation tests were performed in vitro (MS vitamin-enriched medium) in six copper mediums ranging from 0 to 125 μM Cu2+. Results. No significant differences in germination percentage were observed according to the copper concentrations. Crotalaria cornetii had the lowest germination percentage. Root elongation of C. peschiana did not differ with copper concentration, but root elongation of C. cobalticola was higher at the greatest copper concentration (125 μM Cu2+). Conclusions. Even if C. cobalticola presented better growth at highest Cu concentrations, it appeared that C. cobalticola and C. peschiana do not require copper for their early stages of development and could thus be conserved in non-contaminated substrate. Crotalariacornetii seemed to present a physical seed dormancy. [less ▲]

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See detailConcilier la phytostabilisation des sols pollués avec la conservation de la flore cupro-cobalticole dans la région de Lubumbashi : une stratégie nouvelle pour valoriser les écosystèmes extrêmes ?
Boisson, Sylvain ULg; Collignon, Julien; Langunu, Serge et al

in Bogaert, Jan; Halleux, Jean-Marie (Eds.) Territoires périurbains. Développement, enjeux et perspectives dans les pays du Sud (2015)

Tropical cities extend from the urban area in parallel with their economic growth, delimiting a distinct section, the periurban area. In Katanga (Democratic Republic of the Congo), the human health of ... [more ▼]

Tropical cities extend from the urban area in parallel with their economic growth, delimiting a distinct section, the periurban area. In Katanga (Democratic Republic of the Congo), the human health of populations and the environment are threatened by mining activities in these specific areas. Species occurring naturally on copper-cobalt outcrops have a high conservation value and a potential interest in the rehabilitation of sites polluted with trace metals. This study aims to evaluate the success of the combination of the conservation of two copper-cobalt tolerant species (Crotalaria cobalticola and Anisopappus davyi) with phytostabilisation strategies. The establishment of two species from seed to seedling was analyzed in one site in a polluted periurban area and one control site; both were phytostabilized with the grass Microchloa altera. The rate of emergence, the survival and the growth of plants were compared according to the presence of M. altera and amendments (calcium and organic matter). The results highlighted the importance and necessity of the grass cover to the success of seedling establishment of the two studied species. [less ▲]

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See detailMiombo Woodlands : an endangered forest ecosystem in periurban areas of the southeastern cities of Democratic Republic of Congo
Hick, Aurélie ULg; Kizila Wimana, Pacifique; Tooth, Martin et al

Poster (2015, November 26)

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See detailCarrières et Paysage - Synthèse paysagère du mémoire
Joris, Alicia ULg; Pitz, Carline ULg; Mahy, Grégory ULg

Learning material (2015)

Cette étude s’intéresse aux notions et aux évaluations du paysage et se base sur des problématiques liées à l’impact, au réaménagement et au potentiel écologique des carrières après exploitation. Elle ... [more ▼]

Cette étude s’intéresse aux notions et aux évaluations du paysage et se base sur des problématiques liées à l’impact, au réaménagement et au potentiel écologique des carrières après exploitation. Elle propose une analyse du caractère paysager des carrières calcaires après exploitation, recolonisées spontanément en Région Wallonne. Prenant en compte les Directives de la Convention Européenne du Paysage (Conseil de l'Europe, 2000), ce travail a pour objectifs (1) de décrire les unités paysagères formées par ces carrières et (2) d’évaluer leur intérêt paysager. Pour cela deux méthodes inspirées du Landscape Character Assessment (LCA) ont été développées : une lecture sous forme de fiche de terrain et une lecture sous forme d’enquête de perception auprès de parties prenantes. Les résultats globaux ont mis en avant le caractère naturel, harmonieux et particulier des paysages formés par les carrières après exploitation. Les caractéristiques clés sont l’importance visuelle des falaises, des plans d’eau, des masses végétales et de la morphologie en paliers. Les jeux de contrastes, notamment des couleurs et des textures, offerts par le végétal, la roche et l’eau se sont également avérés significatifs. Une qualité paysagère et esthétique a été affirmée et l’enquête a montré que les personnes interrogées se sentent bien face à ces paysages. Ceux-ci peuvent être caractérisés comme stimulants, plaisants, dotés d’un important degré de naturalité, mais peu sécurisant. Des valeurs culturelles, historiques, symboliques et écologiques ont également été pointées comme un potentiel pour ces anciennes carrières. Ces constatations, inscrites dans une dynamique paysagère, posent la question sur la nécessité d’intervenir paysagèrement dans ces milieux et sur les bénéfices généreux, offert par la nature, que nous pourrions tirer si on gérait dans un premier temps les problèmes de sécurité. [less ▲]

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See detailDeveloping biodiversity indicators on a stakeholders' opinions basis: the gypsum industry Key Performance Indicators framework.
Pitz, Carline ULg; Mahy, Grégory ULg; Vermeulen, Cédric ULg et al

in Environmental Science and Pollution Research (2015)

Aims: To establish a common Key Performance Indicators (KPIs) framework for reporting about the gypsum industry biodiversity at the European level. Methods: In order to integrate different opinions and to ... [more ▼]

Aims: To establish a common Key Performance Indicators (KPIs) framework for reporting about the gypsum industry biodiversity at the European level. Methods: In order to integrate different opinions and to reach a consensus framework, an original participatory process approach has been developed among different stakeholder groups: Eurogypsum, European and regional authorities, universities scientists, consulting offices, European and regional associations for the conservation of nature and the extractive industry. The strategy is developed around four main steps: (i) building of a maximum set of indicators to be submitted to stakeholders based on the literature (Focus Group method); (ii) evaluating the consensus about indicators through a policy Delphi survey aiming at the prioritization of indicator classes using the Analytic Hierarchy Process method (AHP) and of individual indicators; (iii) testing acceptability and feasibility through analysis of Environmental Impact Assessments (EIAs) and visits to three European quarries; (iv) Eurogypsum final decision and communication. Results: The resulting framework contains a set of 11 indicators considered the most suitable for all the stakeholders. Conclusions: Our KPIs respond to European legislation and strategies for biodiversity. The framework aims at improving sustainability in quarries and at helping to manage biodiversity as well as to allow the creation of coherent reporting systems. The final goal is to allow for the definition of the actual biodiversity status of gypsum quarries and allow for enhancing it. The framework is adaptable to the local context of each gypsum quarry. [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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See detailChallenges for the restoration of dry calcareous grasslands in quarries: does nature need help?
Pitz, Carline ULg; Piqueray, Julien; Harzé, Mélanie ULg et al

Conference (2015, August 26)

In order to maximize the biodiversity potential of dry calcareous grasslands in former quarries two options are available to managers: (i) allow species to spontaneously recolonize the site, (ii ... [more ▼]

In order to maximize the biodiversity potential of dry calcareous grasslands in former quarries two options are available to managers: (i) allow species to spontaneously recolonize the site, (ii) implement technical support for ecosystem restoration. This study aimed at characterizing the spontaneous communities established in dry area of unexploited quarries and at comparing communities encountered to the succession panel of dry grasslands. To evaluate the ecological succession in quarries, three successional stages where defined: (i) less than three years; (ii) three to 20 years; and (iii) more than 20 years after exploitation. For each successional stage, six parcels were selected and 20 1m2 plots were randomly marked in each parcel. All selected parcels presented dry grasslands abiotic conditions: filtering and stony soils and south orientation. During the 2014 vegetation period, percentage cover of higher plant species was recorded in each plot. Explaining environmental variables including coordinates, altitude, slope (degrees), soil depth, exposure, maximum vegetation height, bare ground cover, moss cover, and shrub cover (%) were measured. Our main results showed that, over decades of time, the ecological succession in dry area of unexploited quarries does not approach a typical formation of dry calcareous grassland. Most recolonizations tended to form meadows communities, except for three sites belonging to a specific landscape context. Potential implications for future quarries restoration will be discussed. [less ▲]

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See detailPromoting quarries biodiversity through partnerships: a Belgian case study
Seleck, Maxime ULg; Harzé, Mélanie ULg; Pitz, Carline ULg et al

Conference (2015, August 25)

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected ... [more ▼]

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected though they are playing a significant role as stepping-stones and regulating green infrastructure in landscapes. In highly urbanized and controlled landscapes, quarries are an exceptional opportunity to maintain rare and threatened transient habitats hosting fugitive species. Such ephemeral biodiversity is hard to manage through a site legal protection status. As exploitation progresses, more permanent, biodiverse habitats settle in abandoned areas but the biologic potential could also be maximized by optimized groundwork through the whole exploitation process. Exploitation plans taking into consideration biodiversity could allow maximizing quarry biodiversity hosting capacity during the exploitation phase and in further rehabilitation schemes. Since 2012 Gembloux Agro-Bio Tech (University of Liège) provides support to FEDIEX - the Belgian federation of extractive industries – in its implementation of a sectorial charter on “Quarries and Biodiversity” that aims at i) raising members’ awareness; ii) promoting the integration of practical recommendations for the protection and management of biodiversity in exploitation plans; iii) quarries’ personnel trainings. Our presentation will trace realizations undertaken under this collaboration, among which the “Mr/Ms Biodiversity” training organized in 2013, 2014 and 2015, the publication of folders popularising the management and enhancement of nature in active quarries and the collaboration in the redaction of a “LIFE in Quarries” project (LIFE Biodiversity) submitted for the 2014 LIFE call. [less ▲]

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See detailSpecies-rich anthropogenic grasslands and the problem of afforestation
Buisson, Elise; Le Stradic, Soizig ULg; Alvarado, Swanni et al

Conference (2015, August)

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See detailPromoting quarries biodiversity through partnerships: a Belgian case study
Seleck, Maxime ULg; Lussis, Benoit; Harzé, Mélanie ULg et al

Conference (2015, June 17)

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected ... [more ▼]

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected though they are playing a significant role as stepping-stones and regulating green infrastructure in landscapes. In highly urbanized and controlled landscapes, quarries are an exceptional opportunity to maintain rare and threatened transient habitats hosting fugitive species. Such ephemeral biodiversity is hard to manage through a site legal protection status. As exploitation progresses, more permanent, biodiverse habitats settle in abandoned areas but the biologic potential could also be maximized by optimized groundwork through the whole exploitation process. Exploitation plans taking into consideration biodiversity could allow maximizing quarry biodiversity hosting capacity during the exploitation phase and in further rehabilitation schemes. In 2012, FEDIEX - the Belgian federation of extractive industries - committed itself to a sectorial charter on “Quarries and Biodiversity”. The charter defines an action plan based on three main axes: i) raising members’ awareness; ii) promoting the integration of practical recommendations for the protection and management of biodiversity in exploitation plans; iii) quarries’ personnel trainings. Since 2012 FEDIEX engaged in a partnership with Gembloux Agro-Bio Tech (University of Liège). Our presentation will trace realizations undertaken under this collaboration, among which the “Mr/Ms Biodiversity” training organized in 2013, 2014 and 2015, the publication of folders popularising the management and enhancement of nature in active quarries and the collaboration in the redaction of a “LIFE in Quarries” project (LIFE Biodiversity) submitted for the 2014 LIFE call. [less ▲]

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See detailCopperflora – an online species-level database of biology, ecology, geography of the flora from the Katangan Copperbelt (D.R. Congo) to manage their conservation
Boisson, Sylvain ULg; Seleck, Maxime ULg; Le Stradic, Soizig ULg et al

Poster (2015, May 21)

Storage and accessibility to structured data are essential in all fields of scientific research. In ecology, conservation managers regularly use thousands qualitative and quantitative data from different ... [more ▼]

Storage and accessibility to structured data are essential in all fields of scientific research. In ecology, conservation managers regularly use thousands qualitative and quantitative data from different partners and studies. In recent years, online databases concerning climate, species traits and distribution have been developed but few offer a comprehensive tool for the management of species conservation at several steps. The Copperflora database was created in order to include a diversity of informations about species (taxonomy, habitats, phenology, pictures, distribution, etc.) but also information concerning seeds collection, conservation, monitoring and tests applied to target species. Copperflora is meant to be an interactive and a dynamic project enhancing the exchange of data. Our project also contributes to the advance in the understanding of metallophyte communities’ conservation and restoration projects. Our database structure is expected to be easily transferable to other conservation actions. [less ▲]

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See detailEtude de la flore spontanée de la carrière de Loën (Belgique) pour de futures restaurations
Pitz, Carline ULg; Monty, Arnaud ULg; Piqueray, Julien et al

Conference (2015, March 04)

Afin de maximiser le potentiel de biodiversité d’une carrière en fin d’exploitation deux options s’offrent au gestionnaire : (1) laisser les espèces recoloniser spontanément le site, (2) mettre en œuvre ... [more ▼]

Afin de maximiser le potentiel de biodiversité d’une carrière en fin d’exploitation deux options s’offrent au gestionnaire : (1) laisser les espèces recoloniser spontanément le site, (2) mettre en œuvre des appuis techniques à la restauration d’écosystèmes. Une méthode hybride associant une recolonisation naturelle et une assistance technique peut également être une opportunité pour le gestionnaire. La recolonisation spontanée des carrières peut, dans certains cas, créer une mosaïque d’habitats diversifiés pour des coûts faibles par rapport à des projets de réhabilitation ou de restauration couteux. Toutefois, l’intérêt biologique des habitats issus de successions spontanées peut fortement varier d’un site à l’autre en fonction de l’historique de gestion, des conditions climatiques et édaphiques locales, de l’isolement du site dans le paysage et du pool régional d’espèces présentes. Afin d’évaluer la nécessité ou non de mise en œuvre d’une restauration active d’habitats en carrière, il est nécessaire de caractériser les habitats issus de la succession spontanée ainsi que leur valeur biologique. L’évaluation de l’intérêt biologique d’un habitat prend en compte à la fois la diversité biologique locale (diversité alpha) et l’originalité des communautés présentes par rapport à un référentiel paysager (diversité béta). Ce projet a pour objectif de caractériser la flore recolonisant spontanément les zones xériques non exploitées dans une carrière située en Belgique (Loën, en région wallonne), du point de vue de la diversité spécifique et de la fonctionnalité écologique. Les communautés végétales ont été caractérisées au sein du site de Loën (diversité alpha) et d’un ensemble d’autres carrières représentatives de la diversité des contextes géographiques des carrières calcaires en Région wallonne (diversité béta). [less ▲]

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See detailCaractérisation des systèmes sols-plantes dans les collines de l’arc cuprifère du Katanga (synthèse bibliographique)
Kaya Muyumba, Donato ULg; Liénard, Amandine ULg; Mahy, Grégory ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(2), 204-214

Introduction: The Copper belt of Katanga presents huge resources of Cu and Co-ore. On the copper hills, mineralized rocks outcrop and a specific flora did develop as a response to the high levels of Cu ... [more ▼]

Introduction: The Copper belt of Katanga presents huge resources of Cu and Co-ore. On the copper hills, mineralized rocks outcrop and a specific flora did develop as a response to the high levels of Cu and Co in soil. Soil-vegetation relationships need to be understood in order to elaborate biodiversity conservation programs prior to industrial mining of the copper hills. Literature: This paper reviews knowledge about soil characterization in the copper hills of Katanga and makes proposals for further research about the influence of the very specific chemical conditions of contaminated soils on the vegetation. The focus was put on the geochemical background and the bioavailability of Cu and Co. A lot of progress has been made recently about identification of soil-vegetation relationships. Conclusion: However, the issue of Cu and Co mobility within soil-plant systems is not entirely solved. [less ▲]

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