Nkrumah Philip Nti, van der Ent Antony
Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, The University of Queensland, Queensland, Australia.
Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, The University of Queensland, Queensland, Australia; Laboratoire Sols et Environnement, INRAE, Université de Lorraine, France; Laboratory of Genetics, Wageningen University and Research, The Netherlands.
Sci Total Environ. 2023 Jun 20;878:162791. doi: 10.1016/j.scitotenv.2023.162791. Epub 2023 Mar 11.
Lithium (Li), gallium (Ga) and indium (In) are industry-critical metals, with no known plant species that (hyper)accumulate these metals to any substantial degree. We hypothesised that sodium (Na) hyperaccumulators (i.e., halophytes) may accumulate Li, whilst aluminium (Al) hyperaccumulators may accumulate Ga and In, based on the chemical similarities of these elements. Experiments were conducted in hydroponics at various molar ratios for six weeks to determine accumulation in roots and shoots of the target elements. For the Li experiment, the halophytes Atriplex amnicola, Salsola australis and Tecticornia pergranulata were subjected to Na and Li treatments, whilst for the Ga and In experiment, Camellia sinensis was exposed to Al, Ga, and In. The halophytes were able to accumulate high shoot Li and Na concentrations reaching up to ~10 g Li kg and 80 g Na kg, respectively. The translocation factors for Li were higher than for Na (about two-fold) in A. amnicola and S. australis. The results from the Ga and In experiment show that C. sinensis is capable of accumulating high concentrations of Ga (mean 150 mg Ga kg), comparable with Al (mean 300 mg Al kg), but virtually no In (<20 mg In kg) in its leaves. Competition between Al and Ga suggests that Ga might be taken up via Al pathways in C. sinensis. The findings suggest that there are opportunities to explore Li and Ga phytomining on respective Li- and Ga-enriched mine water/soil/mine waste materials using halophytes and Al hyperaccumulators to complement the global supply of these critical metals.
锂（Li）、镓（Ga）和铟（In）是对工业至关重要的金属，目前尚无已知植物物种能在任何显著程度上（超）积累这些金属。基于这些元素的化学相似性，我们推测钠（Na）超积累植物（即盐生植物）可能积累锂，而铝（Al）超积累植物可能积累镓和铟。通过水培法在不同摩尔比条件下进行了为期六周的实验，以确定目标元素在根和地上部的积累情况。在锂实验中，盐生植物滨藜（Atriplex amnicola）、南方猪毛菜（Salsola australis）和颗粒碱蓬（Tecticornia pergranulata）接受钠和锂处理，而在镓和铟实验中，茶树（Camellia sinensis）暴露于铝、镓和铟。这些盐生植物能够积累较高的地上部锂和钠浓度，分别高达约10 g Li/kg和80 g Na/kg。在滨藜和南方猪毛菜中，锂的转运系数高于钠（约两倍）。镓和铟实验结果表明，茶树能够积累高浓度的镓（平均150 mg Ga/kg），与铝（平均300 mg Al/kg）相当，但其叶片中几乎没有铟（<20 mg In/kg）。铝和镓之间的竞争表明，在茶树中镓可能通过铝的吸收途径被吸收。研究结果表明，利用盐生植物和铝超积累植物，在各自富含锂和镓的矿井水/土壤/矿山废料上探索锂和镓的植物采矿，以补充这些关键金属的全球供应，存在机会。
