以黄土高原的典型工业污染河流北洛河为研究对象，测定其干支流 17 个采样点沉积物中的 8 种重金属（Hg、 As、Cd、Cr、Cu、Pb、Ni、Zn）质量分数，结合描述性统计结果对重金属的空间分布特征进行分析。进一步利用地 累积指数法、内梅罗综合污染指数法和潜在生态风险指数法分析重金属的污染程度与生态风险，利用 PMF 模型 和相关性分析进行来源解析。结果表明：北洛河上游沉积物中重金属的平均质量分数高于中下游，As、Cd 和 Zn 的均值分别为背景值的 1.26、1.28 和 1.41 倍，Zn、Hg、Cd、Pb、As 和 Cu 的变异系数大于 30%，为高度变异水平。 地累积指数法与内梅罗综合污染指数法显示，北洛河上游 B1处和下游 B13处沉积物中重金属污染处于中高水平； 潜在生态风险指数法显示，单一元素污染危害程度依次为 Cd?>?Hg?>?As?>?Cu?>?Ni?>?Pb?>?Zn?>?Cr，整体来看，Cd 和 Hg 的潜在生态危害较大，中游 B10和下游 B13存在中等生态风险，其余点位均为轻微生态风险。来源解析表明，北 洛河沉积物中重金属的 3 个来源分别为交通污染源（30.74%）、煤炭石油类工业污染源（35.51%）及农业活动和自 然母质的混合来源（33.75%）。研究成果可为北洛河沉积物重金属污染的科学治理及流域生态管理提供理论 参考。

With the rapid development of industrialization and urbanization, the wide spread of heavy metal pollution in river sediments is posing a threat to the ecological security. As a typical river on the Loess Plateau, the pollution of Beiluo River is becoming increasingly prominent, whereas no attempt has been made to systematically evaluate the spatial distribution of heavy metals in the watershed. Therefore, the monitoring and analysis of typical heavy metals in sediments of Beiluo River is of great significance to the ecological health of the basin.In June 2021, sediments were sampled from 17 sites in the main and tributaries of the Beiluo River. The spatial distribution of eight heavy metals (Hg, As, Cd, Cr, Cu, Pb, Ni, Zn) was determined by microwave digestion-atomic fluorescence spectrometry and Aqua regia extraction-inductively coupled plasma mass spectrometry, followed by evaluating the degree of heavy metal pollution and the ecological risk assessment using geoaccumulation index, Nemerow pollution index, and potential ecological risk index, respectively. The source apportionment was conducted using Positive Matrix Factorization (PMF) model and Pearson correlation analysis. The distribution characteristics of heavy metals showed that the content of heavy metals in each sampling site varied greatly. In particular, the content of Zn was significantly higher than that of other heavy metals. The highest content of total heavy metals appeared in the upstream B1 (448.46 mg/kg), followed by the downstream B13 (323.43 mg/kg). Some heavy metal contents were higher than the heavy metal background values of Shaanxi Province. The order of coefficient of variation was as follows: Zn (68.21%) > Hg (51.78%) > Cd (49.65%) > Pb (41.61%) > As (31.82%) > Cu (30.77%) > Ni (23.89%) > Cr (23.74%). In the matter of ecological risk assessment, the geoaccumulation index analyses showed that the accumulative conditions of Cd and Zn were moderately polluted, and most of the other heavy metals were at the pollution-free level. The Nemerow pollution index ranged from 0.74 to 3.64, with an average value of 1.37, and the values of more than half of the sites were within 1 to 2, indicating that the overall pollution in the study area was slightly polluted. The mean values of individual potential ecological risk indexes were: Cd (39.05) > Hg (30.37) > As (12.56) > Cu (4.37) > Ni (4.29) > Pb (3.19) > Zn (1.41) > Cr (0.87). The comprehensive ecological risk index ( RI ) values ranged from 51.60 to 199.75, with an average of 96.09. In addition to the intermediate ecological risk at B10 (158.63) in the middle reaches and B13 (199.75) in the lower reaches, risks in all the other sites were low. Conclusions: (1) The results of geoaccumulation index and Nemerow pollution index show that the heavy metal pollution in the upstream B1 and downstream B13 are ranged from the medium to high levels. According to the results of potential ecological risk index, Cd and Hg in the Beiluo River may pose a threat to the ecosystem. In addition to the ecological risks in the middle stream B10 and the downstream B13 that are classified as moderate, the whole basin has slight potential ecological risks. (2) Based on the PMF model and correlation analysis, the sources of heavy metals in the sediments of Beiluo River were analyzed. The results showed that the sources of eight heavy metals could be divided into three categories: traffic pollution sources, coal and oil industrial pollution sources, and mixed sources of agricultural activities and natural parent materials. (3) Based on the results of this study, it is suggested to divide the pollution levels of the Beiluo River basin into regions, focusing on the heavy metal pollution at B1 in the upper reaches and B13 in the lower reaches, especially reducing the input of metal Zn and Hg in the river basin, and taking certain measures to supervise and control related industries involved in heavy metal pollution, so as to eliminate the pollution of heavy metals in the sediments. In future studies, the enrichment characteristics of heavy metals in sediments with different grain sizes will be revealed to provide more comprehensive scientific data for the prediction of heavy metal pollution in sediments and the overall ecological protection of the basin.