Global distribution of clay-size minerals on land surface for biogeochemical and climatological studies

Clay-size minerals play important roles in terrestrial biogeochemistry and atmospheric physics, but their data have been only partially compiled at global scale. We present a global dataset of clay-size minerals in the topsoil and subsoil at different spatial resolutions. The data of soil clay and its mineralogical composition were gathered through a literature survey and aggregated by soil orders of the Soil Taxonomy for each of the ten groups: gibbsite, kaolinite, illite/mica, smectite, vermiculite, chlorite, iron oxide, quartz, non-crystalline, and others. Using a global soil map, a global dataset of soil clay-size mineral distribution was developed at resolutions of 2' to 2° grid cells. The data uncertainty associated with data variability and assumption was evaluated using a Monte Carlo method, and validity of the clay-size mineral distribution obtained in this study was examined by comparing with other datasets. The global soil clay data offer spatially explicit studies on terrestrial biogeochemical cycles, dust emission to the atmosphere, and other interdisciplinary earth sciences. Design Type(s) observational design • data integration objective Measurement Type(s) composition of soil Technology Type(s) data collection method Factor Type(s) Sample Characteristic(s) Shiga Prefecture • Taiwan Island • Indian subcontinent • Fars Province • India • Fukushima Prefecture • Northern California • Argentine Patagonia • Iran • Morteratsch Glacier • Italy • Province of Ontario • Municipality of Kiruna • Ross Dependency • Brazil • Triangulo Mineiro/Alto Paranaiba Mesoregion • Municipality of Manaus Machine-accessible metadata file describing the reported data (ISA-Tab format)