Copper tolerance and accumulation in two cuprophytes of South Central Africa: Crepidorhopalon perennis and C. tenuis (Linderniaceae)

in Environmental & Experimental Botany (2012)

May Rare Metallophytes Benefit from Disturbed Soils Following Mining Activity? The Case of the Crepidorhopalon tenuis in Katanga (D. R. Congo)

in Restoration Ecology (2011), 19

Copper tolerance in the cuprophyte Haumaniastrum katangense (S. Moore) P.A. Duvign. & Plancke

in Plant and Soil (2010), 328(1-2), 235-244

Mapping of soil-sediment systems contaminations around a metal-ore smelter. The example of Cu in Lubumbashi (R.D. Congo)

Conference (2009, December 02)

Tolerance to copper in the cuprophyte Haumaniastrum Katangense (S. Moore) P.A. Duvign. & Plancke

Poster (2009, March 27)

Soil influence on Cu and Co uptake and plant size in the cuprophytes crepidorhopalon perennis and C. tenuis (Scrophulariaceae) in SC Africa.

in Plant and Soil (2009), 317

Mapping of soil-sediment systems contaminations around a metal-ore smelter : The example of Cu in Lubumbashi (R.D.Congo).

Poster (2009)

The Katanga is famous for its high richness in metal ores, mainly Cu- and Co-minerals. The ore treatments activities lead to metal spreading in the environment which do endanger the viability of ... [more ▼]

The Katanga is famous for its high richness in metal ores, mainly Cu- and Co-minerals. The ore treatments activities lead to metal spreading in the environment which do endanger the viability of ecosystems and human health. The contaminations of soils and sediments around the Gecamines smelter in Lubumbashi have been evaluated through a multi-scale approach. In the first stage, a reference system about the natural contents in soils has been implemented. The main units of the detailed (1:20 000) soil map have been characterized through field observations and laboratory determinations : acido-basic and organic status, particle size distribution, cationic exchange capacity, total contents in Al, Fe, Mn, Cu, Co, Cd, Pb, Zn. An exploratory mapping of soil contaminations (Cu, Co, Cd, Pb, Zn) centered on the Gecamines cheminey was then conducted as a second stage of the approach. Detailed investigations were finally performed in the Gecamines district where signs of soil degradation were the highest. The spatial continuity and the differenciation (C : C0+C ratio) of the studied parameters appeared weak. No clear effect of the dominant wind direction on the spatial distribution of the contaminants could be identified despite a clear degradation of the ecosystem in the area under dominant wind. However the detailed approach showed evidences of (i) significant wind deposits in the Gecamines district, (ii) and local man-made deposits but also (ii) important processes of redistribution in the landscape through erosion/sedimentation or anthropic activities. Our results point out the difficulty to identify the sources of contaminations in an urban environment and stress the need to have approaches with complementary levels of details. [less ▲]

Variability of edaphic conditions in metal-contaminated sites at multiple scales. Two case studies in temperate and tropical environments

Conference (2008, August)

In numerous places, mining and ore treatment activities have generated environmental contaminations which endanger ecosystem viability and/or human health. In some places, the ecological pressure induced ... [more ▼]

In numerous places, mining and ore treatment activities have generated environmental contaminations which endanger ecosystem viability and/or human health. In some places, the ecological pressure induced by the metal contaminations allowed the development a specific flora, fromwhich candidates for phytoremediation may be selected. A survey of edaphic conditions prevailing for plant growing in contaminated areas around metal smelters has been conducted in belgian calaminary sites (Zn, Pb, Cd contaminations) and in the Katanga province of RDC (Cu contaminations). As the processes generated by the modifications of the soil environment may affect the form of a trace element, that is its distribution through various pools, we investigated physical and chemical fractionation of some metallic trace elements (Cu, Zn, Pb, and Cd) in soils and compared temperate and tropical cases. The results stress the need for a typology of the contaminations that takes into account the classical pedological parameters, even if contaminated sites are far from classical soil environment. The variability of edaphic properties that can occur within small distances is also an important point to consider when planning rehabilitation operations. [less ▲]

Impacts of alien invasive plants on soil nutrients are correlated with initial site conditions in NW Europe

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 ▲]

Appui à la création d'un diplôme d'études approfondies en biologie végétale et environnement à l'Université de Lubumbashi et remédiation multiscalaire des sols contaminés.

Poster (2007, November)