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Best Spanish doctoral thesis in Soil science in 2015 for CML researcher Daniel Arenas Lago

The Spanish Society of Soil Science has chosen as the best thesis of 2015 (call 2016) in Spain to the CML-researcher Daniel Arenas Lago, for his research at the University of Vigo that expands and deepens in new knowledge about adsorption and retention of heavy metals in soils, an issue increasingly worrisome because many of these items are toxic to organisms and they can enter the food chain producing harmful effects in humans.

Daniel Arenas Lago

The award, which collected begin March 2017 at an event in Madrid, certifies the quality of the analyses of Daniel Arenas and at the same time, also the capacity and reliability of the research group Plant and Soil Science, led by Professor Manuel J. Reigosa. They have gotten in less than ten years three time this award: in 2009 with the thesis of Flora Alonso Vega, co-director of the thesis of Daniel Arenas, for a study on the soil's capacity to retain cadmium, copper and lead, and in 2013 for Veronica Asensio, author of a thesis about the assessment of the quality of the minesoils. "These three awards show the ability to work in our group, despite the lack of funding that exists in Spain compared to other European Union countries," says Daniel Arenas, who is currently performing a postdoc  at the Institute of Environmental Sciences at Leiden University with a postdoctoral contract funded by Xunta de Galicia.

"To receive the SECS award is not only a pride for me and my thesis supervisors, the Drs MarĂ­a Luisa Andrade and  Flora Alonso Vega, also it is an opportunity to transmit the importance of the soil conservation and the sustainable use of the soil. We have to remember that the soil is a natural resource not limited, mainstay of life, and necessary to obtain food, so we must preserve it, and also acts as a barrier and deposition of pollutants, preventing its transfer to other parts ecosystem", says this researcher.

The results of the thesis were published in twelve scientific journals of high impact

The thesis of Daniel Arenas: "Heavy metals in soils. Identification of sorbents, distribution among amorphous and crystalline phases and physiological response of native species", defended in the Faculty of Biology at University of Vigo (Spain) in July 2015 and whose results have led to a dozen publications in scientific journals of high impact. He studied the distribution of heavy metals among the different geochemical phases in natural soils and soils from contaminated mines. In this sense one of the most important innovations of this study was to verified that the combination of Scanning Electron Microscopy and Time of Flight Secondary Ion Mass together with X-ray diffraction and sequential chemical extraction is an effective tool for identifying the sorbents of the soil and determining their affinity for the cations of the heavy metals and for probing their distribution between the amorphous and crystalline phases.

The combined use of these technique made possible to visualize the associations  among  soil components which retain metals and to assess their bioavailability, competition, selectivity and mobility. In this research were studied soils from two mines and two serpentinite quarries from Galicia (Spain)

The results indicated that the conditions of these soils inhibit the growth of vegetation and prevent the development of an optimal coverage, which increase erosion, enhance nutrient loss and provoke serious pollution problems, "not only in the areas, but also an important part of the areas bordering, "so we need your recovery and stabilization."

With this objective (recovery and stabilization) was investigated the physiological response of the plant Cistus Monspeliensis L, which grows spontaneously in mining zones of the Iberian Pyrite Belt (southeast of the Iberian Peninsula), analyzing changes in their metabolism and proving the activation of mechanisms that act against oxidative stress, increasing its tolerance to high concentrations of heavy metals. This demonstrates the phytostabilizator and phytoremediator potential of this plant, which can be used, like other species of the genus Cistus, in phytoremediation activities.

Postdoc in the Netherlands

Daniel Arenas explains that he chose this location because the research group where he is working is one of the most important internationally, who explains that he chose the Netherlands following the recommendations of the co-director of his thesis co-director, Flora Alonso, "whose experience as a postdoc in this country has been very positive."'