Investigating the Vegetation–Soil Relationships on the Copper–Cobalt Rock Outcrops of Katanga (D. R. Congo), an Essential Step in a Biodiversity Conservation Plan

Plant communities of soils naturally enriched in copper and cobalt in Katanga (D. R. Congo) are critically threatened in the short term due to mining activities. For biodiversity conservation and ecosystem restoration purposes, there is an urgent need to acquire more knowledge on those plant communities including their diversity and their relationships to environmental factors. The classification of 62 vegetation plots located in 6 metal-rich rocky hills in the Tenke Fungurume mining area resulted in 3 well-defined steppic and steppic savanna communities. Canonical analysis showed that the community comprising the largest proportion of strictly endemic metallophytes (i.e. species that only occur on metal-rich soils) developed in the soils with the most elevated concentrations of Cu and Co. However, contrasting species assemblages in the two other plant communities were explained by soil nutrients and percentage rocks in addition to heavy metal concentrations. The results of this study will assist with restoration efforts because they (1) provide a rigorous assessment of communities before a disturbance and (2) define essential edaphic conditions needed for the reestablishment of critical communities.

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