Pan Yong-Xing, Chen Meng, Wang Xiao-Tong
College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China.
Guangxi Collaborative Innovation Center for Water Pollution Control and Water Security in Karst Area, Guilin 541004, China.
Huan Jing Ke Xue. 2023 Nov 8;44(11):6071-6084. doi: 10.13227/j.hjkx.202212205.
Taking a typical lead-zinc mining area watershed in northern Guangxi as the research object, the total amount and morphology of nine heavy metals(Zn, Pb, Cd, Fe, Mn, Cu, Cr, Sb, and As) and fine soil property indicators(pH, conductivity, cation exchange, organic matter, and particle size) in the surface soils of the Yangshuo lead-zinc mine were analyzed and determined. The accumulation and distribution of soil heavy metals and their main controlling factors were revealed using correlation, redundancy(RDA), and GeoDetector analyses. In the analytical data of soil samples, the mean values of As, Cd, Fe, Cu, Mn, Pb, and Zn exceeded the background values, in which Cd, Mn, Pb, and Zn were 4.01, 3.15, 5.53, and 9.72 times higher than the background values, respectively, indicating that they were significantly enriched in the surface soil. There were more noticeable spatial differences in distribution, which were higher in the alluvial floodplain accumulation area(1-6) than those in the other areas(7-9). The available states() of Pb and Mn were 48.8% and 57.2%, respectively, with high bioavailability and average potential migration capacity(PMI 0.015-0.068 and 0.036-0.082, respectively). The Zn and Cu had some bioavailability degree, with available states() of 30.9% and 16.8% and moderately available states of 10.9% and 13.6%, respectively. The difference was that Zn had a strong migration capacity(PMI 0.160-0.203), and Cu had an average potential migration capacity(PMI 0.017-0.084). Fe and Cr had a difficult-to-use state()>95%, low bioavailability, and weak migration capacity(PMI<0.005). The results of the analysis of the main controlling factors affecting accumulation and distribution showed that Cr was controlled by cation exchange capacity(CEC) and clay; Fe was controlled by sand; As was controlled by electrical conductivity(EC) and pH; Cu, Zn, Cd, and Sb were controlled by pH and clay; Pb accumulation was controlled by pH and soil organic matter(SOM); Mn was controlled by pH. This study quantified the main controlling factors affecting the accumulation and distribution of soil heavy metals, which can provide a scientific basis for decision making in the prevention and control of soil heavy metal pollution.
以桂北典型铅锌矿区流域为研究对象，对阳朔铅锌矿表层土壤中9种重金属（锌、铅、镉、铁、锰、铜、铬、锑和砷）的总量及形态以及细土性质指标（pH值、电导率、阳离子交换量、有机质和粒径）进行了分析测定。利用相关性分析、冗余分析（RDA）和地理探测器分析揭示了土壤重金属的累积与分布及其主要控制因素。在土壤样品分析数据中，砷、镉、铁、铜、锰、铅和锌的平均值均超过背景值，其中镉、锰、铅和锌分别比背景值高4.01、3.15、5.53和9.72倍，表明它们在表层土壤中显著富集。分布上存在较为明显的空间差异，在冲积洪积平原堆积区（1 - 6）含量高于其他区域（7 - 9）。铅和锰的有效态分别为48.8%和57.2%，生物有效性高，平均潜在迁移能力分别为0.015 - 0.068和0.036 - 0.082。锌和铜有一定生物有效性程度，有效态分别为30.9%和16.8%，中度有效态分别为10.9%和13.6%。不同的是，锌具有较强迁移能力（潜在迁移指数为0.160 - 0.203），而铜具有平均潜在迁移能力（潜在迁移指数为0.017 - 0.084）。铁和铬的难利用态（>95%），生物有效性低，迁移能力弱（潜在迁移指数<0.005）。影响累积与分布的主要控制因素分析结果表明，铬受阳离子交换量（CEC）和黏土控制；铁受砂粒控制；砷受电导率（EC）和pH值控制；铜、锌、镉和锑受pH值和黏土控制；铅的累积受pH值和土壤有机质（SOM）控制；锰受pH值控制。本研究量化了影响土壤重金属累积与分布的主要控制因素，可为土壤重金属污染防治决策提供科学依据。
