References of "Harzé, Mélanie"
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See detailEtude de la flore spontanée de la carrière de Loën pour de futures restaurations - Résultats
Pitz, Carline ULg; Mahy, Grégory ULg; Monty, Arnaud ULg et al

Conference given outside the academic context (2014)

Ce projet a pour objectif de caractériser la flore recolonisant spontanément les zones xériques non exploitées récemment de la carrière de Loën, du point de vue de la diversité spécifique et de la ... [more ▼]

Ce projet a pour objectif de caractériser la flore recolonisant spontanément les zones xériques non exploitées récemment de la carrière de Loën, 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). L’étude a montré que, sur des laps de temps de plusieurs décennies, un processus de succession écologique s’est mis en place au sein du site de Loën, mais que cette succession ne tend pas vers une formation typique de pelouse sèche. Les explications peuvent être d’une part, que la disponibilité et l’apport de graines de pelouses sèches avoisinantes est insuffisant, et d’autre part, que le contexte abiotique pourrait être plus favorable à d’autres types de végétations herbacées. Cette étude illustre que des expériences de semis seraient souhaitable afin de définir les objectifs de restauration de la carrière de Loën et des carrières qui se trouvent dans des situations comparables. [less ▲]

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See detailEtude de la flore spontanée de la carrière de Loën pour de futures restaurations - Rapport final
Pitz, Carline ULg; Mahy, Grégory ULg; Monty, Arnaud ULg et al

Report (2014)

Ce projet a pour objectif de caractériser la flore recolonisant spontanément les zones xériques non exploitées récemment de la carrière de Loën, du point de vue de la diversité spécifique et de la ... [more ▼]

Ce projet a pour objectif de caractériser la flore recolonisant spontanément les zones xériques non exploitées récemment de la carrière de Loën, 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). L’étude a montré que, sur des laps de temps de plusieurs décennies, un processus de succession écologique s’est mis en place au sein du site de Loën, mais que cette succession ne tend pas vers une formation typique de pelouse sèche. Les explications peuvent être d’une part, que la disponibilité et l’apport de graines de pelouses sèches avoisinantes est insuffisant, et d’autre part, que le contexte abiotique pourrait être plus favorable à d’autres types de végétations herbacées. Cette étude illustre que des expériences de semis seraient souhaitable afin de définir les objectifs de restauration de la carrière de Loën et des carrières qui se trouvent dans des situations comparables. [less ▲]

Detailed reference viewed: 13 (4 ULg)
See detailEtude de la flore spontanée de la carrière de Loën pour de futures restaurations
Pitz, Carline ULg; Mahy, Grégory ULg; Monty, Arnaud ULg et al

Conference given outside the academic context (2014)

This project aims to characterize the flora that spontaneously recolonize non recently exploited areas in one group quarry (Loën) from the point of view of species diversity and ecological functionality ... [more ▼]

This project aims to characterize the flora that spontaneously recolonize non recently exploited areas in one group quarry (Loën) from the point of view of species diversity and ecological functionality. Plant communities will be compared with observed plant communities characterized in longest abandoned quarries in the same regions (same pool of potential species) and known plant communities of the dry grassland habitats reference. The project will establish the potential for restoration of dry grasslands in the study site and established for the quarry studied the basic principles of future restoration plans. [less ▲]

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See detailCarrières & Biodiversité - Les pelouses sèches
Harzé, Mélanie ULg; Boisson, Sylvain ULg; Halford, Mathieu ULg et al

Learning material (2014)

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See detailCarrières & Biodiversité - Les plantes invasives
Halford, Mathieu ULg; Boisson, Sylvain ULg; Harzé, Mélanie ULg et al

Learning material (2014)

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See detailCarrières & Biodiversité - Les plans d'eau
Boisson, Sylvain ULg; Harzé, Mélanie ULg; Halford, Mathieu ULg et al

Learning material (2014)

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See detailCarrières & Biodiversité - Les falaises et éboulis
Seleck, Maxime ULg; Boisson, Sylvain ULg; Harzé, Mélanie ULg et al

Learning material (2014)

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See detailCarrières & Biodiversité - Les arènes minérales
Piqueray, Julien; Boisson, Sylvain ULg; Halford, Mathieu ULg et al

Learning material (2014)

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See detailExtent of intra-population functional variability along a local environmental gradient for four calcareous grasslands species
Harzé, Mélanie ULg; Monty, Arnaud ULg; Mahy, Grégory ULg

Conference (2013, August 19)

In the last few years, an increasing body of evidence has highlighted the role of functional traits as reliable predictors of species resistance to disturbance and response to environmental gradients ... [more ▼]

In the last few years, an increasing body of evidence has highlighted the role of functional traits as reliable predictors of species resistance to disturbance and response to environmental gradients. However, most studies focused on functional comparisons at the interspecific level while intraspecific functional trait variation has received remarkably little attention. As intraspecific traits variability is a necessary condition for species to adapt to environmental changes, studying intraspecific functional traits variation along environmental gradients is a major issue in a context of global change. The aim of our study was to evaluate the extent of intraspecific functional variability of four species along an environmental gradient of water stress at a local scale and to compare species response to the gradient. Calcareous grasslands species are present along a xeric gradient from mesophilous to xerophilous grasslands. Changes of exposure, slope and soil depth lead to differences of water availability for plants along the gradient. We measured the maximum vegetative height (MVH), the specific leaf area (SLA, one side area of a fresh leaf divided by its oven-dry mass) and the leaf dry matter content (LDMC, leaf oven-dry mass divided by its water-saturated fresh mass) on randomly selected individuals along a gradient of xericity on three study sites located in south Belgium. Functional traits were measured on about 60 individuals per site and per species. The soil depth was measured around each individual. The exposure and the slope were measured in order to calculate a heat load index for each individual. The extent of local intraspecific functional variability of our data was compared to data covering the species European range. Results are species dependent but for some study species intraspecific functional variability at local scale is not negligible compared to European data. Species functional responses to the gradient (soil depth and heat load index) showed a decrease in SLA and MVH and an increase in LDMC with increasing xericity for all study species. Response extent was species dependent. Main implications for species resistance to disturbance and climate change adaptation will be discussed. [less ▲]

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See detailEvaluation du succès de restaurations de pelouses calcicoles de la vallée du Viroin : densité en individus et succès reproducteur de deux espèces cibles.
Harzé, Mélanie ULg

Master's dissertation (2010)

Calcareous grasslands are local biodiversity « hotspots ». Unfortunately, these exceptional ecosystems have undergone a drastic fragmentation since the abandonment of traditional agro pastoral practices ... [more ▼]

Calcareous grasslands are local biodiversity « hotspots ». Unfortunately, these exceptional ecosystems have undergone a drastic fragmentation since the abandonment of traditional agro pastoral practices. Consequently, many calcareous grassland species are now in danger. In Belgium, since 1990, many hectares of these habitats have been restored to reassemble remaining fragments of calcareous grasslands. The main goal of this work is to participate at the scientific evaluation of calcareous grasslands restoration which took place in the Viroin valley (Namur, Belgium). To reach this goal, information about global and local densities of 2 grasslands species (Helianthemum nummularium and Sanguisorba minor) have been collected on 6 working zones (2 reference grasslands, 2 restored in 1990 and 2 restored in 2006) situated on 2 different sites. Reproductive success traits have been measured on 120 individual samples of each species. Moreover, individuals’ size parameters and some environmental data (soil depth and vegetation structure) have been collected. Results show that global and local densities are lower on recently restored grasslands for both species studied. On the other hand, older restorations and reference grasslands are not significantly different. With regards to the reproductive success of species, individuals on grasslands restored in 2006 have the best results. They produce more flowers, or inflorescences, and more seeds. Differences observed for individuals’ reproductive success have their more probable cause in vegetation structure. The vegetation in the zones that have been restored more recently is more open as the shrubs and trees layer is lower. [less ▲]

Detailed reference viewed: 63 (13 ULg)