School of Physical and Chemical Sciences, University of Canterbury, New Zealand.
Faculty of Agriculture and Life Sciences, Lincoln University, New Zealand.
Chemosphere. 2018 Apr;197:1-6. doi: 10.1016/j.chemosphere.2018.01.012. Epub 2018 Jan 5.
Contamination of soil with lithium (Li) is likely to increase due to its wider dispersal in the environment, associated in particular, with the disposal of the now ubiquitous Li-ion batteries. There is, however, a paucity of information on the behaviour of Li in the soil-plant system. We measured the sorption of added Li to soil, and uptake of Li by food and fodder species. Around New Zealand, soil concentrations were shown to range from 0.08 mg/kg to 92 mg/kg, and to be positively correlated with clay content. Most geogenic Li in soil is insoluble and hence unavailable to plants but, when Li is added to soil, there is only limited sorption of Li. We found that Li sorption increased with increasing soil pH, and decreased proportionately with increasing Li concentrations. Compared to other cations in soil, Li is mobile and may leach into receiving waters, be taken up by plants, or have other biological impacts. In a soil spiked with just 5 mg/kg, plants took up several hundred mg/kg Li into leaves with no reduction in biomass. Lithium appears to be a phloem immobile element, with the highest concentrations occurring in the older leaves and the lowest concentrations occurring in the seeds or fruits. These results may raise concerns and risks in situations where food and fodder crops are associated with waste disposal.
由于锂（Li）在环境中的广泛分布，尤其是与现在无处不在的锂离子电池的处理有关，土壤中锂的污染可能会增加。然而，关于 Li 在土壤-植物系统中的行为的信息却很少。我们测量了添加到土壤中的 Li 的吸附以及食物和饲料物种对 Li 的吸收。在新西兰周围，土壤浓度范围从 0.08 mg/kg 到 92 mg/kg，并且与粘粒含量呈正相关。土壤中大多数原生 Li 是不可溶的，因此对植物不可用，但当 Li 添加到土壤中时，Li 的吸附量有限。我们发现，Li 的吸附量随着土壤 pH 值的增加而增加，随着 Li 浓度的增加而按比例减少。与土壤中的其他阳离子相比，Li 具有移动性，可能会浸出到受纳水中，被植物吸收，或产生其他生物影响。在仅添加了 5 mg/kg 的土壤中，植物将数百毫克/千克的 Li 吸收到叶子中，而生物量没有减少。Li 似乎是一种韧皮部不可移动的元素，在较老的叶子中浓度最高，在种子或果实中浓度最低。这些结果可能会引起关注，并在与废物处理相关的食物和饲料作物的情况下带来风险。
