Centre SÈVE, Département de biologie, Faculté des Sciences, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Québec, J1K 2R1, Canada; National Research Council Canada, Energy, Mining and Environment, 6100, avenue Royalmount, Montréal, Québec, H4P 2R2, Canada.
Centre SÈVE, Département de biologie, Faculté des Sciences, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Québec, J1K 2R1, Canada.
Chemosphere. 2020 Jul;250:126243. doi: 10.1016/j.chemosphere.2020.126243. Epub 2020 Feb 17.
Mining activities have significant environmental impacts, such as the production of acid mine drainage and the typical absence of vegetation on mine tailings whose absence can facilitate the migration of metals to adjacent ecosystems. We investigated the metal and metalloid composition of plants and substrates on, and near a former gold mine site to understand elemental dynamics in such environments. A mine tailings deposit rich in Mo and As in Northwestern Québec was studied following the natural colonization of the deposit by boreal plant species. The site and surrounding forest were categorized into 6 vegetation density classes (VDC) to determine if and how vegetation density, and plant elemental composition, and soil properties were linked. Macroelemental composition of plant tissues (P, K and Ca) was relatively stable, despite differences in macroelemental levels of substrates between different VDC (with lower macronutrient levels associated with less dense areas), indicating the adaptability of the three species studied (Alnus incana spp. rugosa, Betula papyrifera and Picea spp.). Results showed that across a wide range of substrate properties, it was plant species and density that explained metal and metalloid composition in plant tissues (leaves, stems, and roots), while the main environmental determinants for this were VDC, pH, Ca and Cu. Increasing vegetation density was associated with decreasing As and Mo concentrations in substrates. This study sheds light on the plasticity of alder, spruce and birch growing on mine sites, allowing us to better understand elemental dynamics on such sites, and ultimately improve their management.
采矿活动对环境有重大影响，例如产生酸性矿山排水，以及矿山尾矿上典型的缺乏植被，这使得金属更容易迁移到相邻的生态系统中。我们研究了以前金矿场遗址上和附近植物和基质中的金属和类金属组成，以了解这些环境中的元素动态。魁北克西北地区富含 Mo 和 As 的矿山尾矿被研究了，这些尾矿是在北方树种自然定殖后形成的。该地点和周围森林被分为 6 个植被密度类（VDC），以确定植被密度以及植物元素组成和土壤特性是否以及如何相关。尽管不同 VDC 之间的基质宏元素水平存在差异（与较不密集的区域相关的宏养分水平较低），但植物组织的宏元素组成（P、K 和 Ca）相对稳定，这表明了三种研究物种（Alnus incana spp. rugosa、Betula papyrifera 和 Picea spp.）的适应性。结果表明，在广泛的基质特性范围内，是植物物种和密度解释了植物组织（叶片、茎和根）中的金属和类金属组成，而这方面的主要环境决定因素是 VDC、pH 值、Ca 和 Cu。植被密度的增加与基质中 As 和 Mo 浓度的降低有关。这项研究揭示了在矿山场地上生长的桤木、云杉和桦树的可塑性，使我们能够更好地了解这些场地上的元素动态，并最终改善它们的管理。
