State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Environ Sci Pollut Res Int. 2019 Jan;26(2):1615-1627. doi: 10.1007/s11356-018-3691-6. Epub 2018 Nov 16.
Complex land use patterns and intense human activities significantly affect the spatial distribution of heavy metals in soils. This is especially true in peri-urban areas. The land use in peri-urban areas is complex and the risk of heavy metal pollution is relatively high. Identifying the correlations between land use patterns and spatial distribution of heavy metals in peri-urban soils is important for enhancing soil security and sustaining soil ecosystem services in areas undergoing rapid urbanisation. In this study, soil samples were collected from 82 experimental sites in a typical peri-urban watershed in eastern China. Copper (Cu), zinc (Zn), cadmium (Cd), nickel (Ni), arsenic (As), chromium (Cr), lead (Pb) and mercury (Hg) concentrations at different soil depths were analysed. Results showed that heavy metal concentrations in peri-urban soils were significantly affected by land use type and varied with soil depth. Farmland had the highest heavy metal concentrations, whereas forestland had the lowest concentrations; the concentrations in soils decreased with increasing soil depth. Spatial analysis of heavy metals in soils showed that their concentrations rapidly increased with the increasing percentage of town areas in buffer zones. This indicated that land use structure influenced the heavy metal concentrations in peri-urban soils and the influences were correlated to the locations of towns and villages. Correlation analysis showed that Cu, Zn, Cd, Pb and Hg concentrations in soils were significantly affected by altitude, distance from roads, distance from towns and villages and soil clay content. Interestingly, historic land use was also found to affect heavy metal concentrations in forestland. These results can provide scientific guidance for designing effective soil management practices for peri-urban areas.
复杂的土地利用模式和强烈的人类活动显著影响土壤中重金属的空间分布。这在城市周边地区尤其如此。城市周边地区的土地利用复杂，重金属污染风险相对较高。确定城市周边土壤中土地利用模式与重金属空间分布之间的相关性，对于提高土壤安全性和维持快速城市化地区的土壤生态系统服务至关重要。在本研究中，从中国东部一个典型的城市周边流域的 82 个实验点采集了土壤样本。分析了不同土壤深度下铜（Cu）、锌（Zn）、镉（Cd）、镍（Ni）、砷（As）、铬（Cr）、铅（Pb）和汞（Hg）的浓度。结果表明，城市周边土壤中重金属浓度受土地利用类型的显著影响，并随土壤深度而变化。农田的重金属浓度最高，而林地的重金属浓度最低；土壤深度增加，重金属浓度降低。土壤重金属的空间分析表明，随着缓冲区中城镇面积百分比的增加，其浓度迅速增加。这表明土地利用结构影响城市周边土壤中的重金属浓度，而这种影响与城镇和村庄的位置有关。相关分析表明，土壤中 Cu、Zn、Cd、Pb 和 Hg 浓度受海拔、距道路的距离、距城镇和村庄的距离以及土壤粘粒含量的显著影响。有趣的是，历史土地利用也被发现会影响林地中的重金属浓度。这些结果可为城市周边地区的土壤管理实践提供科学指导。
