GEMAS – Chemistry of Europe’s Agricultural soils, Single element maps, Li - Lithium

GEMAS (Geochemical Mapping of Agricultural and Grazing Land Soil in Europe) is a cooperative project between the Geochemistry Expert Group of EuroGeoSurveys and Eurometeaux. In total, more than 60 international organisations and institutions worldwide were involved in the implementation of the project. During 2008 and 2009, a total of 2219 samples of agricultural (arable land soils, 0 – 20 cm, Ap samples) and 2127 samples of grazing land (pasture land soils, 0 – 10 cm, Gr samples) soil were collected at a density of 1 site/2 500 km² each from 33 European countries, covering an area of 5,600,000 km². All samples were analysed for 52 chemical elements after an aqua regia extraction, 41 by XRF (total), TC and TOC. In addition, the agricultural soil samples were analysed for 57 elements in a mobile metal ion (MMI®) extraction and Pb isotopes. All analytical results were subject to tight external quality control procedures. The GEMAS project thus provides for the first time fully harmonised data for element concentrations and bioavailability of the elements at the continental (European) scale. The downloadable files present the areal distribution of the element contents determined by different analytical methods in the shape of colour shaded contour maps with a classification in 7 and 72 levels each.GEMAS（欧洲农业与牧场土壤地球化学测绘，Geochemical Mapping of Agricultural and Grazing Land Soil in Europe）是欧洲地质调查联盟（EuroGeoSurveys）地球化学专家小组与欧洲金属测量协会（Eurometeaux）的合作项目。全球共有60余家国际组织与机构参与了本项目的实施。2008年至2009年间，项目组从33个欧洲国家的560万平方千米覆盖区域内，以每2500平方千米1个采样点的密度，采集耕地土壤（0~20cm，即Ap样品（Ap samples））2219份、牧场土壤（0~10cm，即Gr样品（Gr samples））2127份。所有样品经王水萃取法前处理后，针对52种化学元素开展分析，其中41种元素通过X射线荧光光谱法（XRF）、总碳（TC）及总有机碳（TOC）完成检测。此外，农业土壤样品还通过可移动金属离子（MMI®）萃取法，对57种元素及铅同位素进行了分析检测。所有分析结果均严格遵循外部质量控制流程进行核验。因此，GEMAS项目首次在欧洲大陆尺度上，提供了元素浓度与元素生物有效性的统一标准化数据集。可下载文件以彩色分层等值线图的形式，展示了不同分析方法测得的元素含量空间分布，两类分级标准分别包含7级与72级。