Abstract Agricultural soil (Ap-horizon, 0–20 cm) samples were collected from 33 European countries as part of the GEMAS (GEochemical Mapping of Agricultural and grazing land Soil) soil-mapping project. The Mg data derived from total concentrations (XRF) and two acid digestion methods, aqua regia (AR) and Mobile Metal Ion (MMI®), were used to provide an overview of its spatial distribution in soil at the continental-scale. Magnesium is one of the most abundant elements in the Earth’s crust and essential nutrient for plants and animals and its presence in soil is, therefore, important for soil quality evaluation. In this study, the geochemical behaviour of Mg in European agricultural soil was investigated in relation to a variety of soil parent materials, climatic zones, and landscapes. The chemical composition of soil reflects mostly the primary mineralogy of the source bedrock, and the superimposed effects of pre- and post-depositional chemical weathering, controlled by element mobility and formation of secondary phases such as clays. Low Mg concentrations in agricultural soil occur in regions with quartz-rich glacial sediments (Poland, Baltic States, N. Germany), and in soil developed on quartz-rich sandstone parent materials (e.g., central Sweden). High Mg concentrations occur in soil developed over mafic lithologies such as ophiolite belts and in carbonate-rich regions, including karst areas. The maximum extent of the last glaciation is well defined by a Mg concentration break, which is marked by low Mg concentrations in Fennoscandia and north-central Europe, and high Mg concentrations in Mediterranean region. Lithology of parent materials seems to play a key role in the Mg nutritional status of agricultural soil at the European scale. Influence from agricultural practice and use of fertilisers appears to be subordinate. Comparison of the continental-scale spatial distribution of Mg in agricultural soil by using the results from three analytical methods (XRF, AR and MMI®) provides complementary information about Mg mobility and its residence time in soil. Thus, allowing evaluation of soil weathering grade and impact of land use exploitation.

中文翻译：

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GEMAS：欧洲农业土壤中镁的地球化学分布

摘要 作为 GEMAS（农业和牧场土壤地球化学制图）土壤绘图项目的一部分，从 33 个欧洲国家收集了农业土壤（Ap-horizo​​n，0-20 cm）样品。来自总浓度 (XRF) 和两种酸消化方法、王水 (AR) 和移动金属离子 (MMI®) 的镁数据用于提供大陆尺度土壤中其空间分布的概览。镁是地壳中含量最丰富的元素之一，是动植物必需的养分，因此，镁在土壤中的存在对于土壤质量评估非常重要。在这项研究中，镁在欧洲农业土壤中的地球化学行为与各种土壤母质、气候带和景观有关。土壤的化学成分主要反映源基岩的主要矿物学，以及沉积前和沉积后化学风化的叠加效应，受元素迁移率和粘土等次生相形成的控制。农业土壤中的低镁浓度出现在富含石英的冰川沉积物地区（波兰、波罗的海国家、德国北部）和在富含石英的砂岩母体材料上发育的土壤中（例如，瑞典中部）。镁铁质岩性（如蛇绿岩带）和富含碳酸盐的地区（包括喀斯特地区）的土壤中出现高浓度的镁。最后一次冰期的最大范围由镁浓度中断很好地定义，其特点是芬诺斯坎迪亚和欧洲中北部的低镁浓度和地中海地区的高镁浓度。在欧洲范围内，母体材料的岩性似乎对农业土壤的镁营养状况起着关键作用。农业实践和肥料使用的影响似乎是次要的。使用三种分析方法（XRF、AR 和 MMI®）的结果比较农业土壤中 Mg 的大陆尺度空间分布，提供了关于 Mg 迁移率及其在土壤中的停留时间的补充信息。因此，允许评估土壤风化等级和土地利用开发的影响。使用三种分析方法（XRF、AR 和 MMI®）的结果比较农业土壤中 Mg 的大陆尺度空间分布，提供了关于 Mg 迁移率及其在土壤中的停留时间的补充信息。因此，允许评估土壤风化等级和土地利用开发的影响。使用三种分析方法（XRF、AR 和 MMI®）的结果比较农业土壤中 Mg 的大陆尺度空间分布，提供了关于 Mg 迁移率及其在土壤中的停留时间的补充信息。因此，允许评估土壤风化等级和土地利用开发的影响。