East China University of Technology, Nanchang, 330000, China; Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China.
Environ Pollut. 2020 May;260:114065. doi: 10.1016/j.envpol.2020.114065. Epub 2020 Jan 28.
Intensive anthropogenic activity has triggered serious heavy metal contamination of soil. Land use and land cover (LULC) changes bear significant impacts, either directly or indirectly, on the distribution of heavy metal in soils. A total of 180 samples were acquired from various land covers at different depths, namely surface soils (020 cm) and subsurface soils (20-40 cm). Spatial interpolation, geographically weighted regression (GWR) and self-organizing map (SOM) were used to discern how variations in the spatial distributions of soil heavy metals were caused by human activities for different land uses, and how these pollutants contributed to environmental risks. The medium concentrations of Cd, Cr, Cu, Pb and Zn in surface soil all exceeded the corresponding local background values in flat cropland and developed area soil. The overall ecological risk level of the study varied from low to medium. The GWR model indicated that the land use intensity had a certain influence on the accumulation of heavy metals in the surface soil. K-means clustering of the SOM revealed that the type of LULC also contributed to the redistribution of heavy metals in the surface soil.
人为活动的加剧引发了土壤严重的重金属污染。土地利用和土地覆盖（LULC）的变化直接或间接地对土壤中重金属的分布产生重大影响。共采集了 180 个样本，来自不同土地覆盖的不同深度，即表层土壤（0-20cm）和亚表层土壤（20-40cm）。空间插值、地理加权回归（GWR）和自组织映射（SOM）被用来识别不同土地利用方式下人类活动如何导致土壤重金属空间分布的变化，以及这些污染物如何导致环境风险。平原耕地和发达地区土壤中表层土壤中 Cd、Cr、Cu、Pb 和 Zn 的中浓度均超过相应的本地背景值。研究区的整体生态风险水平从低到中不等。GWR 模型表明，土地利用强度对表层土壤中重金属的积累有一定影响。SOM 的 K-均值聚类表明，土地利用类型也有助于表层土壤中重金属的再分布。
