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汾河下游河岸带土壤中重金属污染特征评价及污染源分析
Characteristics Evaluation and Source Analysis of Heavy Metals in Riparian Soils of Lower Reaches of Fenhe River
为了解汾河下游河岸带土壤中重金属的污染特征及污染来源,选取汾河下游8个断面32个土壤样品作为研究对象,分析重金属含量及分布特征,利用单因子污染指数法和潜在生态风险指数法评价重金属污染程度及潜在生态风险,通过主成分分析(PCA)和正定矩阵因子分析法(PMF)对重金属的污染源进行解析。结果表明:汾河下游河岸带土壤重金属含量整体偏低,Cu、Zn和Cr含量未超出山西省重金属背景值,但Pb和Hg的含量分别是背景值的1.3倍和2.6倍;土壤中重金属整体生态风险较低,只有部分土壤样品中Hg和Pb分别处于中度-重度、中度生态风险水平,Pb和Hg可能会对当地的生态环境带来危害,是重金属管控的重点。根据重金属污染源解析结果可知,Cr受到人类活动影响较小,其含量变化可能因土壤母质和地质活动造成;Hg污染主要来源为工业生产;Cu的污染来源有工业生产和农业活动及交通运输;Zn和Pb具有同源性,主要受到工矿企业生产、农业活动和交通运输的影响。
[Objective] This study aims to understand the pollution characteristics and sources of heavy metals in the riparian soil of the lower reaches of the Fenhe River. [Methods] We collected 32 soil samples from 8 sections in the lower reaches of the Fenhe River and analyzed the content and distribution characteristics of heavy metals. The degree of heavy metal pollution and potential ecological risks were evaluated using the single-factor pollution index method and the potential ecological risk index method. The sources of heavy metals were analyzed through principal component analysis (PCA) and positive matrix factorization (PMF). [Results] 1) The content of heavy metals in the riparian soils of the lower reaches of the Fenhe River was generally low, but the enrichment effects of Pb and Hg were significant. The points with higher contents of Cu, Zn, Cr, Pb and Hg were mainly distributed in urban suburbs and the industrial areas concentrated along the riverbanks. The content of heavy metals in the Yellow River estuary area was relatively low. 2) The potential ecological risk index (PERI) was the highest downstream of Linfen City, at river confluences, and in Hejin City. Hg and Pb were at moderate-severe and moderate ecological risk respectively. This may be affected by the emission of Hg vapor from coal-fired power plants and coking plants downstream of Linfen City and Hejin City, as well as the sedimentation of smoke dust from lead smelters. The river confluences were areas where substances precipitated and accumulated, which was conducive to the enrichment of heavy metals. Industrial parks were scattered in areas such as Xiangfen County and Jishan County, resulting in a higher content of heavy metals in the middle of the lower reaches than in areas flowing into the Yellow River. In the areas with moderate ecological risks of heavy metals Hg and Pb, the contribution rates of Hg and Pb were 54.92% and 31.28%, respectively, indicating that Hg and Pb were the key elements for controlling soil heavy metal pollution in the lower reaches of the Fenhe River. 3) The correlation analysis results among heavy metals showed that there was a significant correlation between Zn and Pb, with a correlation coefficient of 0.671, indicating the influence of human activities on heavy metals in the soil. The high content of Pb in the soil may be caused by the waste gas and waste residue from surrounding industrial and mining enterprises. Dust and wastewater from human activities also caused Zn to enter the soil. The results showed that agricultural production was an important source of Zn and Pb. The unreasonable use of chemical fertilizers and pesticides for agricultural irrigation in the lower reaches of the Fenhe River led to the long-term accumulation of Zn and Pb in the soil, and the exhaust emissions from agricultural machinery also caused the accumulation of Pb in the soil. The dust and waste gas from mining, smelting, and electroplating production of minerals in the study area were deposited into the soil after rainfall, resulting in an increase in the contents of Zn and Pb in the soil. 4) According to PMF simulation, the main source of Hg was industrial production. Cu in the soil had multiple sources, including industrial production, agricultural activities, and transportation. Cr was relatively stable and less affected by human activities. The changes in Cr content were mainly influenced by soil parent materials and geological activities. [Conclusion] In summary, the main sources of heavy metal pollution in the soil along the lower reaches of the Fenhe River are human activities and industrial production. Controlling heavy metal sources at the origin can gradually reduce the heavy metal pollution in basin soils. At the same time, it can also reduce the heavy metal content in the tributary basins of the Yellow River, which is conducive to the overall ecological protection of the Yellow River.
重金属污染特征 / 污染源解析 / 主成分分析(PCA) / 正定矩阵因子分析法(PMF) / 风险评价 / 汾河下游 / 河岸带
heavy metal pollution characteristics / pollution source analysis / PCA / PMF / risk assessment / lower reaches of Fenhe River / riparian zone
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With the rapid development of industrialization and urbanization, the issue of soil environmental pollution is becoming more and more prominent, especially concerning heavy metal contamination, which has garnered significant scholarly attention. The surface watershed formed by waterline is influenced by various factors such as topography, industrial emissions, and agricultural runoff, resulting in a complex process of migration and accumulation of heavy metal elements from multiple sources. In this study, the pollution characteristics and sources of heavy metal elements Hg, As, Pb, Ni, Cd, Cr, Cu and Zn in 165 surface soil samples from the Manghe River watershed in Jiyuan City were comprehensively analyzed using a variety of methods, including statistics, geostatistics, enriched factor analysis and the Positive Matrix Factorization Model (PMF). The results showed that the concentrations of Hg, Cd, As, Cu, Pb and Zn exceeded their corresponding background values with varying degrees of enrichment. Notably, the average contents of Cd, Hg and Pb were 26.70 times, 3.69 times and 4.49 times higher than those in Chinese soils on average, respectively, showing obvious enrichment characteristics. Moreover, there were distinct spatial distribution patterns for each heavy metal element; Ni and Cr exhibited similar trends mainly controlled by the parent material, while human activities significantly affect the other six elements forming high-value areas around mining and related industries. It is noteworthy that Cu, Hg and Zn were influenced by dominant wind direction in autumn and winter, forming sub-high-value zones in southern forested areas; meanwhile, Cu and Zn were also influenced by agricultural fertilizer application as well as surface runoff, leading to secondary high-value areas in the dryland areas. Further analysis revealed a significant positive correlation among these heavy metal elements, suggesting that they may share common sources. Through the PMF Model, four main factors were identified, with factor 2 (36.25%), factor 1 (23.00%), factor 3 (21.20%) and factor 4 (19.55%) ranked in descending order of contribution rate. The heavy metal pollution in the study area was attributed to anthropogenic activities and natural factors, accounting for 63.75% and 36.25%, respectively. Coal mining, chemical industry smelting, vehicle emissions and excessive use of agrochemicals were identified as the main sources of heavy metal pollution. These pollutants entered the soil through direct emissions, atmospheric deposition, transportation and agricultural activities, exerting a significant impact on the soil environment. Therefore, delving into the spatial distribution pattern of soil heavy metal pollution and precise analysis of its sources are of great importance for effective treatment and remediation of soil heavy metal pollution in small watersheds, maintaining healthy soil ecology and safeguarding human health.
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Current source apportionment models have successfully identified emission sources and quantified their contributions. However, when being utilized for heavy metal source apportion in soil, their accuracy needs to be improved, regarding migration patterns. Therefore, this work intended to improve the pre-existing principal component analysis and multiple linear regression with distance (PCA-MLRD) model to effectively locate pollution pathways (traffic emissions, irrigation water, atmospheric depositions, etc.) and achieve a more precise quantification. The dataset of soil heavy metals was collected from a typical area in the Chang-Zhu-Tan region, Hunan, China in 2021. The identification of the contribution of soil parent material was accomplished through enrichment factors and crustal reference elements. Meanwhile, the anthropogenic emission was identified with principal component analysis and GeoDetector. GeoDetector was used to accurately point to the pollution source from a spatial differentiation perspective. Subsequently, the pollution pathways linked to the identified sources were determined. Non-metal manufacturing factories were found to be significant anthropogenic sources of local soil contamination, mainly through rivers and atmospheric deposition. Furthermore, the influence of irrigation water on heavy metals showed a more pronounced effect within a distance of 1000 m, became weaker after that, and then gradually disappeared. This model may offer improved technical guidance for practical production and the management of soil heavy metal contamination.
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Heavy metal(loid)s (HMs) pollution has become a common and complex problem in industrial parks due to rapid industrialization and urbanization. Here, soil and groundwater were sampled from a retired industrial park to investigate the pollution characteristics of HMs. Results show that Ni, Pb, Cr, Zn, Cd, and Cu were the typical HMs in the soil. Source analysis with the positive matrix factorization model indicates that HMs in the topsoil stemmed from industrial activities, traffic emission, and natural source, and the groundwater HMs originated from industrial activities, groundwater-soil interaction, groundwater-rock interaction, and atmosphere deposition. The sequential extraction of soil HMs reveals that As and Hg were mainly distributed in the residue fraction, while Ni, Pb, Cr, Zn, Cd, and Cu mainly existed in the mobile fraction. Most HMs either in the total concentration or in the bioavailable fraction preferred to retain in soil as indicated by their high soil-water partitioning coefficients (K), and the K values were correlated with soil pH, groundwater redox potential, and dissolved oxygen. The relative stable soil-groundwater circumstance and the low active fraction contents limited the vertical migration of soil HMs and their release to groundwater. These findings increase our knowledge about HMs pollution characteristics of traditional industrial parks and provide a protocol for HMs pollution scrutinizing in large zones.Copyright © 2023. Published by Elsevier B.V.
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胡杰, 赵心语, 王婷婷, 等. 太原市汾河河岸带土壤重金属分布特征、评价与来源解析[J]. 环境科学, 2022, 43(5): 2500-2509.
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徐飘飘, 周建武. 温州市某农田土壤重金属污染污染源识别及风险评估[J]. 浙江农业科学, 2023, 64(7):1813-1816.
对温州市某农田范围的土壤重金属污染状况进行来源分析及污染评价,采集了该区域范围内48个土壤样品并进行分析,并采用相关性分析和主成分分析的方法进行定性的源识别,最后利用单因子指数及内梅罗综合指数进行污染评价。结果表明,Cd、Pb、Zn、As的平均含量都超过浙江省背景值,而Cu、Cr、Ni三种重金属未超标。由相关性分析、主成分分析可知,Cr、Ni、Cu可能来源于成土母质,As、Cd、Pb、Zn来源于人为活动;根据内梅罗综合指数评价可知,该地区污染超标率为100%,主要为轻度污染,As、Cd、Pb、Zn均有不同程度的污染,其中Cd污染较为严重。
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The treatment of contaminated groundwater using integrated bone char and biochar beds has been studied. The bone char and biochar were made in a locally built double-barrel retort utilising cow bones, coconut husks, bamboo, neem trees, and palm kernel shells at 450 °C and were graded into 0.05- and 0.315-mm sizes. Eight groundwater treatment experiments (BF2-BF9) were performed in columns with bed heights of 8.5-16.5 cm to remove nutrients, heavy metals, microorganisms, and interfering ions from groundwater using bone char, biochar, and a combination of bone and biochar. The water samples were analysed for twenty-one water quality parameters including pH, total dissolved solids, conductivity, turbidity, fluoride, chloride, sodium, and potassium. The rest were total coliforms, faecal coliforms, total heterotrophic bacteria, Escherichia coli, manganese, and total iron. The effectiveness of the treatment processes was assessed using the Ghana standard authority and the World Health Organisation's recommended values for drinking water quality. The results were shared using a simplified single-factor index, Nemerow's pollution index, and a heavy metal pollution index with decision-makers as a technology for groundwater treatment in rural communities in Africa. Bone char was more effective in removing total heterotrophic bacteria than any of the other treatment agents tested. This is because of its compact nature and small particle size. The quality of water treated by BF3, BF5, BF6, BF7, BF8, and BF9 was fit for drinking based on the single-factor and heavy-metal pollution evaluation because they have the lowest level of pollution. However, Nemerow pollution analysis found only BF5 to be the most suitable for public use.© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.
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底泥是水库生态内源污染重要释放源。为全面了解山东省黄岛区主要水库底泥中重金属含量及其潜在生态危害程度，采集了黄岛区狄家河水库在内的10个水库的水样，测试了底泥中Hg、Cd、Pb、Cr、Cu、Zn、Ni、Fe、Mn和As等10种重金属含量，分析了各元素的含量，利用多方法综合对水库底泥污染程度及潜在的生态风险进行评价，并结合周边生活、生产环境分析了重金属的可能来源。结果表明，西寨水库Hg含量超过标准要求，花沟水库Cd含量超过标准要求，其余水库各重金属含量均未超过标准要求；底泥重金属污染程度由强到弱依次为：Hg＞Cd＞Zn＞Pb≥Cu≥As＞Ni≥Cr，Hg、Cd为最主要的重金属污染元素；重金属潜在生态危害由强到弱依次为：Hg＞Cd＞As＞Pb＞Cu＞Cr＞Ni＞Zn，Hg、Cd是潜在的生态危害元素。花沟水库、吉利河河道、西寨水库、狄家河水库，尤其是西寨水库，污染程度较为严重，水库污染的因素主要为人为因素，主要来源为工业污水和生活用水排放。
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Bottom mud is an important source of release of ecological endogenous pollution of reservoirs. In order to comprehensively understand the content of heavy metals in the bottom mud of major reservoirs in Huangdao District， Shandong Province and its potential ecological hazards. In this paper， samples of 10 reservoirs， including Dijiahe Reservoir in Huangdao District， tested 10 heavy metal contents such as Hg， Cd， Pb， Cr， Cu， Zn， Ni， Fe， Mn and As in the sludge， analyzed the content and source of each element， and analyzed the degree of sediment pollution and potential Ecological risks are evaluated， and possible sources of heavy metals are analyzed. The results show that the Hg content of Xizhai Reservoir exceeds the standard requirements， the Cd content of Huagou Reservoir exceeds the standard requirements， and the content of the rest of heavy metals does not exceed the standard requirements. The degree of heavy metal pollution in the bottom mud of Huangdao Reservoir is from strong to weak： Hg>Cd>Zn>Pb≥Cu≥As>Ni≥Cr， and Hg and Cd are the most important heavy metal pollution elements. The potential ecological hazards of heavy metals are from strong to weak： Hg>Cd>As>Pb>Cu>Cr>Ni>Zn. Hg and Cd are potential ecological hazard elements. Huagou Reservoir， Geely River Channel， Xizhai Reservoir and Dijiahe Reservoir， especially Xizhai Reservoir， have a serious degree of pollution. The main factors of reservoir pollution are mainly man-made factors， and the main sources are industrial sewage and domestic water discharge. |
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采用电感耦合等离子体质谱仪和原子荧光分光光度计测定了长江源区主要河流沉积物及周边土壤中14种重金属的含量,并采用富集因子法评价了长江源区主要河流沉积物及土壤中重金属富集程度,同时分析了河流沉积物及沿岸土壤中重金属分布特征及来源。研究结果表明:长江源区主要河流表层沉积物中,除Ni、Pb、Cd、Hg四种重金属外,其他元素含量均低于中国沉积物的平均含量;沉积物中Hg、Ni和Cd存在一定富集;与长江源区其他河流沉积物中重金属相比,沱沱河Cd含量相对较高,楚玛尔河重金属含量均相对较低,而通天河Hg和Fe含量相对较高;沉积物中重金属主要受自然因素影响。土壤中Ni、Pb、Cd、Ti略高于青海省土壤背景值,但重金属富集程度均较低;与长江源区其他河流沿岸土壤中重金属相比,当曲Cr、Ni、Cu含量相对较高,沱沱河Pb、Cd、Sb和Tl含量相对较高,而通天河V含量相对较高;重金属主要受自然因素影响,但部分重金属可能受交通因素影响。研究成果可为长江源区生态环境保护提供基础支撑。
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The concentrations of 14 heavy metals in sediments and surrounding soils of major rivers in the source region of the Yangtze River were detected by using inductively coupled plasma mass spectrometry and atomic fluorescence spectrophotometer. The accumulation of heavy metals was evaluated by enrichment factor method, and the distribution characteristics and sources of heavy metals were also analyzed. Results unraveled that except for Ni, Pb, Cd, and Hg, all other heavy metals in river sediments were lower than the background values of sediments in China; however, Hg, Ni, and Cd were enriched in sediments. Compared with other rivers in the source region, Tuotuo River suffered from a relatively high concentration of Cd, Tongtian River was subjected to high concentrations of Hg and Fe, while Chumar River boasted a low concentration of all heavy metals. The heavy metals in sediments were mainly affected by natural factors. In terms of bank soils, the concentrations of Ni, Pb, Cd, and Ti were slightly higher than the background values of soils in Qinghai Province, yet with light enrichment.Compared with the soils along other rivers in the source region, the bank soil along Dangqu River had high concentrations of Cr, Ni, and Cu, and Tuotuo River Pb, Cd, Sb, and Tl, whereas Tongtian River saw a high concentration of V. The heavy metals in bank soils along rivers were mainly affected by natural factors, and also some affected by traffic factors. The research achievements offer fundamental support for the eco-environmental protection in the source region of the Yangtze River.
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贾佳瑜, 刘小芳, 赵勇钢, 等. 汾河流域下游农田土壤重金属空间分布特征与污染评价[J]. 干旱区资源与环境, 2021, 35(8): 132-137.
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董苗, 高燕, 张永清. 汾河临汾段污灌区土壤重金属污染评价[J]. 河南农业科学, 2014, 43(9): 72-78.
为全面了解汾河临汾段污灌区土壤重金属污染状况,对该区土壤Zn、Cu、Ni、Pb、Cd、Cr、Hg、As含量进行检测,并采用地累积指数法和潜在生态危害指数法对土壤重金属污染进行评价。结果表明,汾河临汾段污灌区土壤Zn、Cu、Pb、Cd、Hg、As平均含量均超过了山西省土壤背景值;各重金属平均含量均未超过国家土壤环境质量标准二级标准值,仅Ni、Pb、As分别有5%、37%、1%的采样点超过了国家土壤环境质量标准二级标准值,但所有样点均未超过国家土壤环境质量标准三级标准值。汾河临汾段污灌区土壤各重金属地累积指数表现为Hg>Cd>Pb>Cu>Zn>As>Ni>Cr,各重金属潜在生态危害系数表现为Hg>Cd>Pb>As>Cu>Ni>Cr>Zn,土壤环境总体处于无至中-强度污染水平,存在强度危害风险。污染较严重的重金属元素不仅受灌溉水质影响,还与灌溉次数、农业施肥、交通运输、工矿企业生产、日常生活和生产活动密切相关。
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许泰, 鄂崇毅. 高寒沼泽草甸土壤重金属富集特征及潜在生态风险[J]. 长江科学院院报, 2023, 40(5): 70-76.
为了解祁连山国家公园土壤重金属的污染程度、生态风险以及空间分布特征,选取祁连山南麓腹地高寒沼泽草甸土壤为研究对象,分析测定了沼泽草甸土壤0~10 cm与10~20 cm中的V、Cr、Mn、Ni、Cu、Zn、Cd、Pb、As、Hg共10种重金属元素的含量。采用污染系数和富集系数对重金属在不同部位的富集规律及污染特征进行研究,并辅以人为贡献率进行补充和验证,最后通过潜在生态风险指数量化评定风险状况。结果表明:① 在0~10 cm和10~20 cm沼泽草甸土壤中,Cr、Zn、Hg的平均含量高于青海湖土壤背景值,其中Cr与Zn呈略微富集,而Hg的富集最为显著且人为贡献率达到了30%;V、Mn、Ni、Cu、Cd、Pb、As的平均含量与自然值无异,人为贡献率均为负值,并随着深度增加呈增大趋势,需要注意的是在部分样点存在点源污染。② 重金属潜在生态风险值从大到小依次为Hg>Cd>As>Ni>Cu>Pb>Cr>V>Zn>Mn,单项潜在生态风险指数显示除Hg以外,其他9种重金属均处于1级轻微生态污染风险状态;沼泽草甸土壤重金属综合潜在生态风险指数(RI)在0~10 cm和10~20 cm都达到了2级中等生态污染等级,Hg对综合潜在生态风险的贡献率达到50%以上。总体来说,沼泽草甸土壤中重金属污染具有一定的潜在风险,在对沼泽湿地污染治理过程中应予以足够的重视,此研究可为祁连山南麓腹地生态环境的整治与改善提供基础性的数据资料。
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吕建树, 张祖陆, 刘洋, 等. 日照市土壤重金属来源解析及环境风险评价[J]. 地理学报, 2012, 67(7):971-984.
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A total of 445 surface soils samples were collected at the nodes of a 2×2 km grid from Rizhao City and analyzed for 10 heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb and Zn). Sources of heavy metals pollutant and the differences of contents among various land use types and parent material were revealed by multivariate analysis; meanwhile, spatial distribution of hazardous risk from heavy metals contamination was given by geostatistics based on GIS. The results are shown as follows. (1) The mean concentrations of As, Co, Cr and Cu were lower than the background values (BV) in eastern Shandong Province, respectively; but those of Cd, Hg, Mn, Ni, Pb and Zn exceeded the BV, especially for Cd and Hg (1.85 and 1.38 times of BV, respectively), indicating distinct accumulations of some heavy metals in soils of Rizhao City. (2) A total of 10 heavy metals could be classified as 4 Principal Components (PCs), including PC1 (Co, Cr, Mn, Ni and Zn), PC2 (Cd, Pb), PC3 (As, Cu), and PC4 (Hg). PC1 and PC3 were the factors dominated by natural sources, PC2 represented the factors from industrial, agricultural and traffic sources, and PC4 was contributed by industrial sources. Pb and Zn with a high load in different PCs might originate from the mixed sources including anthropogenic and natural sources. (3) There were significant differences in Cd and Hg contents among various land cover types with the highest level in urban areas. The concentrations of Co, Cr, Cu, Mn and Ni in the soils from weathered granite and metamorphic rock were all higher than those in the soils from alluvial and marine deposits. (4) The single element, elements integration and the corresponding PC presented similar spatial patterns of hazardous risk. The high risk regions with comprehensive assessment on all elements were located in densely-populated urban areas and western study area, which was attributed to the higher geological background in the western part and strong human interference in the eastern part.
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宋刚福, 丁孟浩, 米晓, 等. 陆浑水库滨岸带沉积物重金属污染评价及其迁移能力分析[J]. 华北水利水电大学学报(自然科学版), 2023, 44(1): 100-108.
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| [23] |
刘祖艳, 焦菊英, 李建军, 等. 青海省典型农业区土壤重金属风险评价及来源[J]. 地球科学与环境学报, 2024, 46(6): 816-831.
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| [24] |
于元赫, 吕建树, 王亚梦. 黄河下游典型区域土壤重金属来源解析及空间分布[J]. 环境科学, 2018, 39(6):2865-2874.
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