School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan 430074, China.
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Wuhan 430074, China.
Int J Environ Res Public Health. 2022 Sep 2;19(17):10971. doi: 10.3390/ijerph191710971.
Increased concentrations of heavy metals in soil due to anthropogenic activities pose a considerable threat to human health and require constant attention. This study investigates the spatial distribution of heavy metals (Cd, Pb, Zn, Sb) and metalloids (As) in a typical alluvial-lacustrine transition basin and calculates the bioavailable forms of elements posing a direct threat. Qualitative and quantitative methods were used to identify the sources of contaminants, after which an ecological risk assessment was conducted. Total (T) As, Pb, and Zn decreased with the depth, whereas Cd and Sb increased in surface (0-20 cm) soil. Bioavailable (Bio) Cd and Pb in the topsoil were regulated by pH and organic matter, whereas Bio-Zn was regulated by soil pH. Within deeper soil layers, the combined effects of pH, organic matter, and clay contents regulated the bio-elements. The results of multiple methods and local investigation showed that TSb (65.3%) was mainly derived from mining activities, TCd (53.2%) and TZn (53.7%) were derived from direct pollution by industrial production and agricultural fertilizers, respectively, and TA (55.6%) was mainly derived from the soil parent material. TPb was related to vehicle exhaust emissions and atmospheric deposition from industrial activities. Although the potential ecological risk in the study area remains relatively low, there is a need for continuous monitoring of the potential ecological risks of Cd and Sb. This study can act as a reference for the prevention and mitigation of heavy metal contamination of alluvial-lacustrine transition basins.
由于人为活动导致土壤中重金属浓度增加，对人类健康构成了相当大的威胁，需要持续关注。本研究调查了典型的冲积-湖泊过渡盆地中重金属（Cd、Pb、Zn、Sb）和类金属（As）的空间分布，并计算了构成直接威胁的元素的可利用形态。采用定性和定量方法识别污染物的来源，然后进行生态风险评估。总（T）As、Pb 和 Zn 随深度减少，而 Cd 和 Sb 在表层（0-20cm）土壤中增加。表层土壤中可利用（Bio）Cd 和 Pb 受 pH 值和有机质调节，而 Bio-Zn 受土壤 pH 值调节。在更深的土壤层中，pH 值、有机质和粘粒含量的综合作用调节了生物元素。多种方法和当地调查的结果表明，TSb（65.3%）主要来源于采矿活动，TCd（53.2%）和 TZn（53.7%）分别来源于工业生产和农业肥料的直接污染，而 TA（55.6%）主要来源于土壤母质。TPb 与车辆排放和工业活动的大气沉降有关。尽管研究区的潜在生态风险仍然相对较低，但仍需持续监测 Cd 和 Sb 的潜在生态风险。本研究可为预防和减轻冲积-湖泊过渡盆地重金属污染提供参考。
