GEMAS – Chemistry of Europe’s Agricultural soils, Parameters and indices, CEC (cation exchange capacity)

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. In addition to the chemical element contents, soil properties and soil parameters such as pH, particle size distribution, effective cation exchange capacity (CEC), MIR spectra and magnetic susceptibility were investigated in the samples and some coefficients were calculated. The downloadable files present the areal distribution of the determined CEC (cation exchange capacity) in the shape of colour shaded contour maps.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）是欧洲地质调查协会（EuroGeoSurveys）地球化学专家组与Eurometeaux合作开展的项目。全球共有超过60家国际组织与科研机构参与了本项目的实施。2008至2009年间，研究团队从欧洲33个国家、总面积达560万平方千米的区域内，以每2500平方千米1个采样点的密度，共采集了2219份农业土壤样品（耕地土壤，0–20厘米，Ap样品）与2127份牧场土壤样品（牧草地土壤，0–10厘米，Gr样品）。除测定土壤化学元素含量外，团队还对样品的土壤理化性质与相关参数展开了分析，包括pH值、粒度分布、有效阳离子交换量（CEC）、中红外光谱以及磁化率，并计算了部分系数。本次可下载文件以彩色晕染等值线图的形式，展示了实测有效阳离子交换量（CEC）的空间分布特征。