National

Soil pollution is one of the major threats facing terrestrial ecosystems. Metal mine wastes from ore processing are among the most hazardous residues. These wastes are often deposited in open-air piles (mine tailings). Classic restoration approaches usually involve topsoil capping aiming to create a new soil above wastes and then afforestation. Despite this, millions of hectares worldwide are occupied by former abandoned, non-restored or deficiently restored, tailings. Classic restoration options have been questioned in semiarid regions due to ecosystem inability to be self-sustaining.

The work is structured in two tasks:
Task 1. Report including the interpretation and evaluation of the soil sampling and analysis campaign. A report must be drawn up interpreting the results obtained in the sampling and analytical campaign carried out by the Directorate General for Biodiversity, Forests and Desertification in order to then proceed to the evaluation of the soils present in the wadis from the point of view of their danger or risk to human health and the environment.

PHASE 1. Initial proposal on the possible treatment lines (similar to a study of alternatives) including information on their feasibility and recommendations for the design of the lines (first conceptual or strategic advance).

Mine tailings piles (left over from mining refining operations) store waste from ore processing and are considered the main responsible for the environmental problems in former metal mining areas. Due to the large number of abandoned piles, public authorities must prioritize actions in those that pose an unacceptable risk and where urgent  action is necessary due to the collapsing risk and/or proximity to cities. These types of actions are much expensive, since they involve a high technical-engineering

Soil pollution is one of the major threats facing terrestrial ecosystems. Metal mine wastes from ore processing are among the most hazardous residues (high metal levels, extreme pH, high salinity, organic matter/nutrients deficiency, poor physical structure). These wastes are often deposited in open-air piles (mine tailings). Classic-restoration approaches (technical reclamation) usually involve topsoil capping aiming to create a new soil above wastes and then afforestation. These options have been questioned in (semi)arid regions due to ecosystem inability to be self-sustaining.

Global climate change might intensify the hazardous effects of anthropogenic metal contamination in terms of soil toxicity risks and thus effects of loss of soil functionality and sustainability. The scientific research performed in this field has been mostly focused on the effects of single climate factors, while less attention has been paid to the combination of multiple climate factors.

The proposal includes field and experimental phases. The latter will be performed in mesocosms. The field part has as a main goal to evaluate the influence of edpahic gradients in the structure of the microbial populations in semiarid mine tailings. In addition, the effects of seasonal dynamics on ecology/ecophysiology of selected endemic plant species will be performed.