Contamination of agricultural soils with heavy metals is a growing global concern with an increase in anthropogenic activities. Despite local studies conducted, no accurate and comprehensive results about agricultural soils of Iran entirely and regarding the climate have been observed regarding heavy metal concentration. Therefore, the present study is aimed at determining a reliable heavy metal concentration in agricultural soils and evaluate the effect of climate on the average concentrations. To provide harmonized and comparable data, 711 soil surface samples were randomly taken from all of the agricultural soils of Iran during 2016–2018. Also, to evaluate the effect of climate, samples were divided into three parts according to major climates of studied area. Results revealed that the average concentration of Cd, Cr, Co, Cu, Mn, Ni, Pb, Zn, and V in agricultural soils was 0.31, 101, 27.9, 37.2, 702, 68.0, 28.2, 73.0, and 101 mg/kg, respectively. The concentration of Cr, Ni, Co, V, and Pb in, respectively, 28.4, 11.3, 8.72, 1.60, and 1.34% of soil samples was higher than the national standard in contrast to the concentration of the other element, which was lower. There were no significant differences between the average concentrations of heavy metals in agricultural soils with respect of climate, indicating the minimum effects of soil forming factors on soil heavy metals. Comparing the mean concentration of heavy metals in three major climatic zones of the country, it seems that geochemistry is the key factor controlling the concentration of metals in agricultural soils of Iran.

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不同气候区域下农业土壤中重金属的浓度：以伊朗为例

随着人为活动的增加，全球土壤对农业土壤的污染日益引起人们的关注。尽管进行了本地研究，但仍未观察到有关伊朗农业土壤整体以及有关重金属浓度的气候方面的准确而全面的结果。因此，本研究旨在确定农业土壤中可靠的重金属浓度，并评估气候对平均浓度的影响。为了提供统一且可比的数据，2016-2018年期间，从伊朗所有农业土壤中随机抽取了711个土壤表面样品。另外，为了评估气候的影响，根据研究区域的主要气候将样品分为三个部分。结果显示Cd，Cr，Co，Cu，Mn，Ni，Pb，Zn，农业土壤中的V和V分别为0.31、101、27.9、37.2、702、68.0、28.2、73.0和101 mg / kg。与其他元素相比，土壤样品中28.4％，11.3％，8.72％，1.60％和1.34％的Cr，Ni，Co，V和Pb的浓度高于国家标准，而其他元素的浓度则较低。农业土壤中重金属的平均浓度在气候方面没有显着差异，表明土壤形成因子对土壤重金属的影响最小。比较该国三个主要气候区的重金属平均浓度，似乎地球化学是控制伊朗农业土壤中金属浓度的关键因素。与其他元素相比，土壤样品中28.4％，11.3％，8.72％，1.60％和1.34％的Cr，Ni，Co，V和Pb的浓度高于国家标准，而其他元素的浓度则较低。农业土壤中重金属的平均浓度在气候方面没有显着差异，表明土壤形成因子对土壤重金属的影响最小。比较该国三个主要气候区的重金属平均浓度，似乎地球化学是控制伊朗农业土壤中金属浓度的关键因素。与其他元素相比，土壤样品中28.4％，11.3％，8.72％，1.60％和1.34％的Cr，Ni，Co，V和Pb的浓度高于国家标准，而其他元素的浓度则较低。农业土壤中重金属的平均浓度在气候方面没有显着差异，表明土壤形成因子对土壤重金属的影响最小。比较该国三个主要气候区的重金属平均浓度，似乎地球化学是控制伊朗农业土壤中金属浓度的关键因素。较低。农业土壤中重金属的平均浓度在气候方面没有显着差异，表明土壤形成因子对土壤重金属的影响最小。比较该国三个主要气候区的重金属平均浓度，似乎地球化学是控制伊朗农业土壤中金属浓度的关键因素。较低。农业土壤中重金属的平均浓度在气候方面没有显着差异，表明土壤形成因子对土壤重金属的影响最小。比较该国三个主要气候区的重金属平均浓度，似乎地球化学是控制伊朗农业土壤中金属浓度的关键因素。