Uusitalo Jonatan F, Linderholm Hans W, Gunnarson Björn E
Department of Physical Geography, Stockholm University, Stockholm, Sweden.
Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden.
Environ Sci Pollut Res Int. 2025 Jun;32(30):18174-18192. doi: 10.1007/s11356-025-36721-9. Epub 2025 Jul 12.
Heavy metal pollution from untreated or poorly managed mining waste is a major environmental concern, leading to the leaching of contaminants into surrounding ecosystems. Traditional monitoring methods are costly and limited in their ability to reconstruct historical contamination trends. Dendrochemical methods offer a promising alternative for assessing long-term pollution dynamics. This study investigates temporal patterns of copper (Cu), nickel (Ni), and zinc (Zn) accumulation in tree rings from 22 European aspens (Populus tremula) growing near an abandoned copper mining field in southeastern Sweden. Tree rings were analyzed using energy-dispersive X-ray fluorescence (ED-XRF), while corresponding soil samples were examined for heavy metal concentrations and pH. Considerable heterogeneity in Cu and pH was observed, with elevated Cu levels across the site. Although no significant correlations were found between soil and tree-ring metal concentrations, increased accumulation of Cu, Ni, and Zn was detected in the trees. Temperature showed a more consistent influence on metal uptake than precipitation. Anomalous uptake increased under warmer and wetter conditions but was absent during severe drought. This study emphasizes the potential of dendrochemical methods for monitoring historical pollution. It highlights the need to refine sampling strategies to better account for localized soil and climatic factors, thereby improving the reliability of dendrochemical methods in assessing pollution trends.
未经处理或管理不善的采矿废弃物造成的重金属污染是一个重大的环境问题，导致污染物渗入周围生态系统。传统的监测方法成本高昂，且在重建历史污染趋势方面能力有限。树木化学方法为评估长期污染动态提供了一种有前景的替代方法。本研究调查了瑞典东南部一个废弃铜矿区附近生长的22棵欧洲山杨（Populus tremula）年轮中铜（Cu）、镍（Ni）和锌（Zn）积累的时间模式。使用能量色散X射线荧光光谱法（ED-XRF）分析年轮，同时检测相应土壤样品中的重金属浓度和pH值。观察到铜和pH值存在相当大的异质性，整个场地的铜含量都有所升高。虽然在土壤和年轮金属浓度之间未发现显著相关性，但在树木中检测到铜、镍和锌的积累增加。温度对金属吸收的影响比降水更为一致。在温暖湿润的条件下异常吸收增加，但在严重干旱期间则不存在。本研究强调了树木化学方法在监测历史污染方面的潜力。它突出了需要改进采样策略，以更好地考虑局部土壤和气候因素，从而提高树木化学方法在评估污染趋势方面的可靠性。
