基于APCS-MLR和PMF模型解析黄河下游文化公园土壤重金属污染特征及来源分析

选取黄河下游典型人类扰动区——黄河文化公园为研究区域，系统采集表层土壤样品，测定土壤中7种(Cr、 Ni、 Cu、 Zn、 Cd、 Pb和As)重金属含量，利用地累积指数研究公园土壤重金属污染特征，应用克里格空间插值法、绝对因子分析-多元线性回归模型(APCS-MLR)和正定矩阵因子分解(PMF)模型解析黄河文化公园土壤重金属的来源.结果表明，研究区表层土壤重金属(Cd、 Zn、 Cu、 Pb和As)含量平均值高于黄河下游潮土区土壤元素背景值，分别是背景值的4.62、 1.78、 1.41、 1.08和1.03倍.除Zn外，其他元素含量均低于黄河流域沿线不同区域土壤相应元素值.7种元素地累积指数递减趋势为：Cd>Zn>Cu>Ni>Pb>As=Cr,元素Cd属于偏中污染，在表层土壤中积累明显.空间分布特征及源解析结果显示，Cr、 Ni和Cu为自然源因子，主要受成土母质影响；Cd和Pb为交通源，Zn和As属于受少量人类活动和自然叠加影响的混合源.APCS-MLR的分析结果显示：自然源贡献率为46.67%,交通源贡献率为24.11%,混合源贡献率为16.12%,...

Pollution Characteristics and Source Analysis of Heavy Metals in Soils in Yellow River Cultural Park Based on APCS-MLR and PMF Receptor Model

With open spaces and good ecological environments, urban parks have become the first choice for the leisure and entertainment of many people. Therefore, the quality of park soil environments has gradually attracted the extensive attention of scholars. In this study, we take the Yellow River Cultural Park, a typical human disturbance area in the lower reaches of the Yellow River, as the research area to discuss the characteristics and sources of heavy metal pollution in the soil. Thirty-three soil surface samples were collected from the Yellow River Cultural Park, and the contents of seven heavy metals (Cr, Ni, Cu, Zn, Cd, Pb, and As) were determined using an inductively coupled plasma emission spectrometer (ICP-AES) and an inductively coupled plasma mass spectrometer (ICP-MS). The geo-accumulation index and geo-statistics method were used. Meanwhile, the absolute factor analysis-multiple linear regression (APCS-MLR) receptor model and positive matrix factorization (PMF) analysis model were employed to reveal the sources of soil heavy metals. The results showed that the average contents of heavy metals (Cd, Zn, Cu, Pb, and As) in the surface soil of the study area were 4.62, 1.78, 1.41, 1.08, and 1.03 times higher than the background values of soil elements in the tidal soil area of the lower reaches of the Yellow River, respectively. Except for Zn, the contents of other elements were lower than the corresponding values of soil elements in different regions along the Yellow River Basin. Among the seven heavy metal elements, the coefficients of variation of Cd and As were greater than 50%, showing obvious spatial variability. The decreasing trend of the accumulation index of the seven elements was Cd>Zn>Cu>Ni>Pb>As=Cr, and the element Cd belonged to the middle pollution category, which was obviously accumulated in the surface soil. The spatial distribution of heavy metals in the soil differed:the high contents of Cr, Cu, and Ni were distributed in the southwest and northeast, and the high-value areas of Cd and Pb were consistent with the areas of human activity intensity. The high-value areas of Zn and As were located in the center of lacustrine sediments. The combined results of the APCS-MLR and PMF models suggested that the first pollution source of soil heavy metal elements in the Yellow River Cultural Park could have been a natural source, the second pollution source may have been a transportation source, and the third source of pollution was judged as a mixed source. Human activities such as transportation sources and mixed sources were the main sources of heavy metal soil pollution, and Cr, Cu, and Ni were affected by natural factors. The contribution rates of APCS-MLR were 46.67%, 24.11%, 16.12%, and 13.10%, respectively, and the contribution rates of PMF were 35.50%, 35.48%, and 29.02%, respectively. This research can provide a basis for improving the ecological environment quality of the park and improving the health level of the population and can also provide support for the ecological environment risk management and comprehensive management along the Yellow River.