Abstract Soil Quality Reference Values (QRV) refer to the natural heavy metal concentrations that is not influenced or is minimally influenced by anthropogenic activities. Such values are unique of each environment, and their extrapolation to different locations becomes inadequate. This research aimed to determine the natural concentrations of metals in soils (QRV) developed on essentially basaltic lithology and tropical conditions in the south of Brazil. Seventy-two soil samples from the Forest Conservation Areas in the west of the state of Parana, Brazil, were obtained. The extraction and dosage of Ag, As, Ba, Cd, Cr, Cu, Mo, Ni, Pb, Sb, V, and Zn were carried out employing methods USEPA 3051a and ICP-OES. The QRV was set to 75th percentile of each element, from the detection and exclusion of the outliers. The natural concentration of all heavy metals was related to the geological context of the basaltic area in Brazil. There was no influence of the pedogenetic degree of soils on the natural heavy metal concentration. The only relevant process for reducing the natural heavy metal levels was the Fe and Mn oxide solubility promoted by hydromorphic conditions. Fe oxides had a significant role in the maintenance of structural and adsorbed heavy metal forms in soils. The results may help the research and monitoring of environmental heavy metals in soils developed from basalt under tropical conditions.

中文翻译：

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热带条件下基性岩发育土壤中重金属质量参考值

摘要 土壤质量参考值（QRV）是指不受人为活动影响或受人为活动影响最小的天然重金属浓度。这些值在每个环境中都是独一无二的，它们对不同位置的外推变得不够充分。这项研究旨在确定在巴西南部基本上是玄武岩岩性和热带条件下形成的土壤中金属的自然浓度 (QRV)。获得了来自巴西巴拉那州西部森林保护区的 72 个土壤样品。Ag、As、Ba、Cd、Cr、Cu、Mo、Ni、Pb、Sb、V 和 Zn 的提取和添加采用 USEPA 3051a 和 ICP-OES 方法进行。通过检测和排除异常值，将 QRV 设置为每个元素的第 75 个百分位数。所有重金属的自然浓度与巴西玄武岩地区的地质环境有关。土壤成土程度对天然重金属浓度无影响。降低天然重金属含量的唯一相关过程是水形条件促进的 Fe 和 Mn 氧化物溶解度。铁氧化物在维持土壤中结构和吸附重金属形态方面具有重要作用。研究结果可能有助于热带条件下玄武岩发育土壤中环境重金属的研究和监测。降低天然重金属含量的唯一相关过程是水形条件促进的 Fe 和 Mn 氧化物溶解度。铁氧化物在维持土壤中结构和吸附重金属形态方面具有重要作用。研究结果可能有助于热带条件下玄武岩发育土壤中环境重金属的研究和监测。降低天然重金属含量的唯一相关过程是水形条件促进的 Fe 和 Mn 氧化物溶解度。铁氧化物在维持土壤中结构和吸附重金属形态方面具有重要作用。研究结果可能有助于热带条件下玄武岩发育土壤中环境重金属的研究和监测。