School of Environment and Sustainable Development, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India.
School of Life Sciences, Central University of Gujarat, Sector-30, Gandhinagar 382030, Gujarat, India.
Sci Total Environ. 2024 Jun 15;929:172560. doi: 10.1016/j.scitotenv.2024.172560. Epub 2024 Apr 18.
Lanthanum (La), the second most abundant rare earth element (REE) is emerging as an environmental issue, with the potential to impact ecosystems and human health. Major sources of soil contamination by La include agricultural, and industrial activities. Lanthanum is non-essential for plant growth but accumulates in various plant parts. The uptake of La by plants is intricately influenced by various factors such as soil pH, redox potential, cation exchange capacity, presence of organic acids and rhizosphere composition. These factors significantly impact the availability and absorption of La ions. Lanthanum impact on plants depends on soil characteristics, cultivated species, developmental stage, La concentration, treatment period, and growth conditions. Excessive La concentrations affect cell division, DNA structure, nutrient uptake, and photosynthesis and induce toxicity symptoms. Plants employ detoxification mechanisms like vacuolar sequestration, osmolyte synthesis, and antioxidant defense system. However, higher concentrations of La can overwhelm these defense mechanisms, leading to adverse effects on plant growth and development. Further, accumulation of La in plants increases the risk for human exposure. Strategies to mitigate La toxicity are, therefore, vital for ecosystem protection. The application of phytoremediation, supplementation, chelation, amendments, and biosorption techniques contributes to the mitigation of La toxicity. This review provides insights into La sources, uptake, toxicity, and alleviation strategies in plants. Identifying research gaps and discussing advancements aims to foster a holistic understanding and develop effective strategies for protecting plant health and ecosystem resilience against La contamination.
镧（La）是第二丰富的稀土元素（REE），正成为一个环境问题，有可能影响生态系统和人类健康。土壤中镧的主要污染来源包括农业和工业活动。镧对植物的生长并非必需，但会积累在植物的各个部位。植物对镧的吸收受到多种因素的复杂影响，如土壤 pH 值、氧化还原电位、阳离子交换能力、有机酸的存在和根际组成。这些因素会显著影响镧离子的可用性和吸收。镧对植物的影响取决于土壤特性、种植物种、发育阶段、镧浓度、处理期和生长条件。过量的镧浓度会影响细胞分裂、DNA 结构、养分吸收和光合作用，并引发毒性症状。植物采用解毒机制，如液泡隔离、渗透物质合成和抗氧化防御系统。然而，较高浓度的镧可能会使这些防御机制不堪重负，对植物的生长和发育产生不利影响。此外，植物中镧的积累增加了人类暴露的风险。因此，采取策略来减轻镧的毒性对于生态系统的保护至关重要。应用植物修复、补充、螯合、改良和生物吸附技术有助于减轻镧的毒性。本综述提供了关于镧在植物中的来源、吸收、毒性和缓解策略的见解。确定研究差距并讨论进展旨在促进对镧污染的全面理解，并制定保护植物健康和生态系统弹性的有效策略。
