Ran Chunmei, Guo Meiqi, Wang Yuan, Li Ye, Wang Jiao, Zhang Yinqing, Liu Chunguang, Bergquist Bridget A, Peng Chu
Department of Earth Sciences, University of Toronto, Toronto, Ontario M5S 3B1, Canada.
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
Eco Environ Health. 2025 Mar 3;4(2):100140. doi: 10.1016/j.eehl.2025.100140. eCollection 2025 Jun.
Evaluating the plant risk of soil pollution by plant physiological indices usually requires a long cycle and has significant uncertainty. In this study, oxidative potential (OP) of the heavy metal contaminated soils was measured by the dithiothreitol method. The oxidative stress response of the model plant ryegrass ( L.) induced by heavy metal contaminated soil was evaluated by the biomarkers, including superoxide dismutase and total antioxidant capacity. The comprehensive biomarker response index has a significant exponential correlation with the OP of soil ( = 0.923, < 0.01) in ryegrass. Metabolomics analysis also showed a significant relationship of the metabolic effect level index of amino acids and sugars with OP. Random forest was selected from four machine learning models to screen the metabolites most relevant to OP, and Shapley additive explanations analysis was used to explain the contribution and the influence direction of the features on the model. Based on the selected 20 metabolites, the metabolic pathways most related to OP in plants, including alkaloid synthesis and amino acids metabolism, were identified. Compared to the plant physiological indices, OP is a more stable and faster indicator for the plant risk assessment of heavy metals contaminated soil.
通过植物生理指标评估土壤污染的植物风险通常需要较长周期且具有显著不确定性。本研究采用二硫苏糖醇法测定重金属污染土壤的氧化电位（OP）。利用包括超氧化物歧化酶和总抗氧化能力在内的生物标志物评估重金属污染土壤诱导的模式植物黑麦草的氧化应激反应。综合生物标志物反应指数与黑麦草土壤OP具有显著指数相关性（R² = 0.923，P < 0.01）。代谢组学分析还表明氨基酸和糖类的代谢效应水平指数与OP存在显著关系。从四个机器学习模型中选择随机森林来筛选与OP最相关的代谢物，并采用Shapley加法解释分析来解释特征对模型的贡献和影响方向。基于选定的20种代谢物，确定了植物中与OP最相关的代谢途径，包括生物碱合成和氨基酸代谢。与植物生理指标相比，OP是评估重金属污染土壤植物风险更稳定、更快速的指标。
