Biogeochemistry in Castilla-La Mancha region: concerns on mining/agriculture relationship.

Castilla-La Mancha (CLM), located in South-Central Spain, is a region of some 80,000 Km² centered in agricultural and livestock activity, being the first major producer of wine and second of olive oil in Spain (after Andalucía), and an important producer of sheep cheese and lamb meal. Besides, the region has supported an important metallic mining activity, including mercury and base metals; these mines, most of them located in the West of the region, are actually closed, but still an important number of industrial minerals (limestone and gypsum as most important, but also other salts and clays varieties) are active in the central and Eastern part of the region.

Up to date, CLM does not have generic reference levels (GRLs) for elemental concentrations; neither it has a distribution map of potentially toxic elements (PTEs) along its territory. These are actually basic needs for regions with economy based on agriculture and livestock.

The project BiGeoQCLM, funded by Consejería de Educación, Cultura y Deportes, Regional Government of CLM, is aimed to obtain a portrait of the distribution of elements in the whole region; the information to collect is aimed to three main objectives: (1): characterize the elemental distribution, including the estimation of GRLs, and the delimitation of the distribution of elements, and in particular of PTEs in the mining areas; together with this, the characterization of the soils of the region, including the distribution of their pedological parameters (2): characterize the soil-to-organisms interactions, including microbiology (through enzymatic activity) and plants (through characterization of elemental plant uptake; and (3): the characterization of the elemental uptake by plants aimed to assess the origin of wine, including the isotopic footprint of soils and wines with certified origin.

The project is in its second year (of three) of development and the work in activity is still mostly related with the field and laboratory work. However, some results are available, and are being presented in other communications of this Conference. In particular, the activity in the South-West of the region, which was the richest in metals-based mining, has been boosted with the starting of the AUREOLE project, funded by European ERA-MIN program, and aimed to find new criteria for the research of Sb and related elements, as well as with the environmental concerns related with the mining of such elements.

This study is being funded by Consejería de Educación, Cultura y Deportes, JCCM (SBPLY/17/180501/000273), with the additional support of project PCI2019-103779, Spanish Ministry of Science and Innovation.