Attending the 12th International Conference on Mine Closure

Last September, the 12th International Conference on Mine Closure was celebrated in Leipzig (Germany). This conference, organized by the Technical University Bergakademie Freiberg, is one of the world`s reference events among the mine closure professionals. The main conference topics that were discussed and that have been found as the main issues were:  establishing integrated life of mine planning, design sustainable land uses from the social and environmental perspective, increasing the post-mining assets value, and establishing  stable and self-regenerating ecosystems, among others.

Due to the urgent necessity of improving reclamation of mining areas, abandoned and/ or in transition to close, researchers from IRNAS-CSIC, University of Seville, University of Reading and Haute École Condorcet have collaborated to present a paper and an oral communication in this conference.

Gil-Martínez M, Domínguez MT, Navarro-Fernández CM, Crompot H, Tibbett M , Marañón T (2018). Long-term effects of trace elements contamination on soil microbial biomass and enzyme activities, in C Drebenstedt, F von Bismarck, A Fourie & M Tibbett (eds), Proceedings of the 12th International Conference on Mine Closure, Technical University Bergakademie Freiberg, Germany, pp. 633-644.

Results from the applied strategy of phytostabilisation on mining areas contaminated by heavy metals were presented. In our study area known as Guadiamar Green Corridor, where phytostabilisation have happened over 19 years, forestation has been found to improve soil fertility and microbial biomass, which is an indicator of improved soil quality. Moreover, different tree species have been found to affect soil chemistry and biology in different ways. White poplar was found to increase soil pH and to recover nutrients levels. However, stone pine was found to acidify the soil, increasing heavy metal availability and reducing microbial communities. In conclusion, previous to forestation is recommended to select the most suitable species for the specific conditions of the mining area to reclaim.

In this conference, Marta Gil-Martínez, predoctoral researcher from IRNAS-CSIC, had the opportunity to visit the Wismut Uranium Tailings Remediation Project , which started back in 1991 and currently clean-up, re-contouring and implementation of covers tasks are still in place. Last cover consists in revegetation to establish some forest and pastures areas, in order to maximize biodiversity.


Presentation in the Iberian Congress of Soil Science

“The soil as sustainable resource for the bioeconomy” was the theme for the VIII Iberian Congress of Soil Sciences, held at San Sebastián/Donosti, during 20-22 June 2018.

Researchers of the projects RECARE and RESTECO contributed to the 3rd session, devoted to “Protection and restoration of soils”, with the comunication titled “Soil restoration strategies in the Guadiamar River Valley. Evaluation of 20 year of monitoring after the Aznalcóllar mining accident”.

This work is a review of the 20-year monitoring of contaminated and remediated soils, after the Aznalcóllar mine-spill. The application of soil amendments (sugarbeet lime and biosolid compost) was evaluated and results of 14-year changes of pH and organic carbon were shown.

At a large scale, in a soil survey along the Agrio and Guadiamar rivers, high level of Cd and Zn were detected in certain spots of channel and river banks.

A copy of the presented poster can be downloaded from Digital CSIC.

International Conference on Mycorrhiza

Last August, the 9th International Conference on Mycorrhiza was held in Prague (Czech Republic). This conference, organised by the International Mycorrhiza Society, provided a global platform for exchanging the latest mycorrhizal symbiosis knowledge (anatomy, molecular mechanisms, mycorrhizal ecology and functioning) as well as its implications for the ecosystems and for the human society.

Researchers from RESTECO Project, together with collaborators, presented their last results in the session “Advances in biological conservation through a better understanding of mycorrhizal ecology”.  A poster was presented with the study of the functional traits of ectomycorrhizal fungi (ECM) in holm oak (Quercus ilex) tree species in trace elements contaminated soils of the Guadiamar Green Corridor (Seville, Spain). In this study, two hypotheses were validated: soil contamination affects ECM species composition and their functionality, and ECM functional traits mediate in the effect of soil contamination on plant status.

Link to the poster: Marta Gil-Martínez et al. “Ectomycorrhizal functional traits mediate plant-soil feedback processes in trace elements contaminated soils”.

Plant functional traits and ecosystem properties

Plant traits resulting from evolutionary and physiological processes have produced a global and extraordinary functional diversity among the myriad of species colonizing contrasted habitats within the planet Earth.

Trait-based ecology helps us to understand better the community assemblage, ecosystem function and the responses to environmental changes.

Researchers of the RESTECO project and the Córdoba University have participated in the Symposium “Trait covariation: structural and functional relationships in plant ecology”, at Exeter (UK) during 27-29 June 2017.

Two comunications were presented:

1) Functional traits of trees affect soil properties and provision of ecosystem services. A study of seven tree species planted on remediated soils in the Guadiamar Green Corridor (Seville, Spain) has shown significant differences in traits (SLA, SRL, LDMC, RMDC) and chemical composition of leaves and roots. These traits differences influence the tree capacity to immobilize contaminants (trace elements) into the soil, remediation technique called phytostabilization. Traits also influence tree capacity to store carbon into biomass and soil, therefore contributing to climate change mitigation.

2) Within plant traits, roots are little known, despite their crucial role in the plant strategies of resource use and the ecosytem funcioning. Variation patterns of 5 root traits in 80 woody plant species from 18 samplig sites and 5 zones of South Spain have been studied. A strong correlation among traits indicates a main dimension along the root economics spectrum. However, other dimensions such as root diameter and the association with mycorrhizal fungi are also relevant.

The abstract and copy of the poster can be consulted in Digital CSIC repository:

Marañón et al. (2017) Traits influence the role of trees on ecosystem services: phytostabilization of trace elements and carbon sequestration.

Villar at al. (2017) Root traits across environmental gradients in Mediterranean woody communities: are they aligned along a single acquisition-conservation axis?

Evaluation of measures to remediate contaminated soils: European meeting

The RECARE project is focused on preventing and remediating degradation of soils in Europe.

A Plenary Meeting has been held at Hella (Iceland), from May 29th to June 2nd 2017. Each of the 17 study sites participating in the project presented their results.

Photo: Erik van den Elsen

The Group SOIL-PLANT, from the IRNAS, CSIC, presented their results about two measures applied for the remediation of contaminated soils at the Guadiamar Green Corridor: a) amendment addition and b) tree plantation.

Those results are part of a joint work by the projects RECARE and RESTECO.

Copies of the presentation and poster can be consulted at the repository Digital CSIC.

International Congress of mediterranean Ecosystems

Researchers of the RESTECO project have presented their results in the International Congress of Mediterranean-type Ecosystems – XIV MEDECOS – which was held at Sevilla, Spain, on February 2017.

In particular, three oral communications were presented within the Symposium “Filling current knowledge gaps: understanding the role of plant-soil interactions on the functioning and resilience of Mediterranean ecosystems in a changing world”:

Marta Gil-Martínez et al. “Understanding feedback processes between holm oak (Quercus ilex) and their ectomycorrhizal fungal symbionts in trace-element polluted soils in Mediterranean ecosystems”.

Álvaro López García et al. “Assessment of the recovery of functional diversity of ectomycorrhizal fungal communities in metal polluted soils”.

Teodoro Marañón et al. “Soil functioning and ecosystem services: using trees to remediate contaminated soils”.

Three poster communications, also related to the project, were presented in other sessions:

María Teresa Domínguez Núñez et al. “Soil contamination and the provision of ecosystem services in Mediterranean lands: implications for livestock and bionergy uses”.

Sara Muñoz Valdés et al. “Modelling resilience and ecosystem services of soils contaminated by heavy metals under remediation measures and Climate Change scenarios: The Case Study of Guadiamar”.

Carmen M. Navarro-Fernández et al. “A functional approach to explore the drivers of mycorrhizal trait variability in Mediterranean plant communities”

Soil organic matter and ecosystem services

The soil organic matter (SOM) plays an important role determining physical (structure, water retention), chemical (nutrient availability, buffer effect), and biological (microbial diversity, biologically active compounds) properties.

There is a generalized problem of organic matter loss in Mediterranean soils, and one of the solutions is to add compost from organic residues, as part of the circular economy.

Soils improved with compost provide with ecosystem services of provision (increasing food production) and regulation (nutrient cycling, carbon sequestration), thus contributing to human wellbeing.


In the Guadiamar Green Corridor (Sevilla, Spain), we are evaluating the effectiveness of combined measures of amendment addition and tree plantation, for two ecosytem services: stabilization of trace elements, and storage of soil carbon.

The IRNAS researchers Teodoro Marañón and Engracia Madejón presented the opening lecture entitled “Soil functions and ecosystem services: the importance of organic matter” (in Spanish), within the V Jornadas de la Red Española de Compostaje, held at Sevilla, Spain, on November 16-18, 2016.

A pdf copy of the slides can be consulted in Digital CSIC repository.

Helping nature to help us

Changes in the natural capital’s properties influence soil processes, which support the provision of ecosystem services. The benefits produced by these ecosystem services are explicitly or implicitly valued by individuals and society. This can influence decision- and policy making at different scales, potentially leading to a societal response, such as improved land management.

A group of scientists within the RECARE project, including Teodoro Marañón (IRNAS, CSIC), has presented a comunication on soil-related ecosystem services at the session Strengthening Ecosystem Services Community of Practices, in the European Ecosystem Services Conference, with the motto “Helping Nature to help us”, that was held at Antwerpen, 19-23 September 2016.


It was proposed an adapted framework for soil-related ecosystem services that is suited for practical application in the prevention and remediation of soil degradation across Europe. It will be applied in the 17 study sites included in the RECARE project.

Gudrun Schwilch, Simone Verzandvoort, Hedwig van Delden, Luuk Fleskens, Elias Giannakis, Teodoro Marañón, Jane Mills, Chris Short, Jannes Stolte (2016). Operationalizing ecosystem services for the mitigation of soil threats. En: European Ecosystem Services Conference, Antwerp, Bélgica, 19-23 septiembre 2016.

A copy of the presentation slides can be consulted here.

Presentation at 5th Ecosummit of Montpellier

ecos2016_300x250The 5th International Ecosummit, Ecological Sustainability, has been held at Montpellier, France, with more than 1,400 participants from 88 countries.

One of the scientific sessions was focused on Soil-plant interactions and soil ecosystem services delivery. In this session, researchers of IRNAS, CSIC have presented results on tree plantations in the Guadiamar Green Corridor (Seville, Spain) and their role in soil trace elements stabilization and carbon sequestration.

The importance of tree-soil interactions was remarked for the delivery of two ecosystem services: 1) improvement of soil quality by phytostabilization of contaminants, and 2) mitigation of climate change by carbon sequestration in biomass and soil.

Marañón, T., Domínguez, M. T., Navarro Fernández, C. M., Madejón, P., Burgos, P., Gil Martínez, M., & Murillo, J. M. (2016). Tree-soil interactions and the provision of ecosystem services in contaminated soils: trace elements phytostabilization and carbon sequestration. 5th International Ecosummit. Ecological sustainability. Engineering change. Montpellier, 29 August-1 September 2016.

Copy in pdf of the slides can be consulted in the CSIC repository.