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| Titel |
Availability of potentially hazardous elements in soils and their transfer to plants. A case study in polluted soils from the Iberian Pyrite Belt (SW Spain) |
| VerfasserIn |
Antonio Romero-Baena, Maria Manuela Abreu, Erika S. Santos, Diego Aran, Isabel González |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250149563
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| Publikation (Nr.) |
 EGU/EGU2017-13923.pdf |
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| Zusammenfassung |
| Protocols for the study of potentially polluted soils by potentially hazardous elements (PHEs)
are based on total element concentration. Nevertheless, the hazard depends on their
availability and ability to be uptake and translocated to edible part of the plants and
consequently to the food chain. Because the bioavailability of elements depends on several
factors, as soil properties and plant species, there is not a universal method for its
evaluation. The objectives of this work are: to assess the bioavailability of PHEs using
different aqueous solutions for chemical elements extraction from different soils and to
evaluate its concentrations in edible part of Lactuca sativa (lettuce) and Petroselinum
crispum (parsley). The study has been carried out in four soils polluted by mining
activities in Tharsis, Sotiel and Riotinto-Nerva areas (Iberian Pyrite Belt, SW Spain).
The soils show high concentration in PHEs (e.g. As 471-1645, Cu 333-1455, Pb
1143-5131, Zn 273-1371 mg/kg). The pH is neutral (7.1-7.9) and the content in
organic carbon ranges from 34 to 85 g/kg. For this purpose, experimental work
was performed in greenhouse conditions in pots filled with 1.5 kg soil/pot (n=5
per soil). Lettuce and parsley seedlings (11 and 6 cm height, respectively) were
transplanted. After six weeks of growth, plants were harvested and soil samples were
collected.
The availability of PHEs in soils (beginning and end of the assay) has been assessed by
extraction with different aqueous solutions: water (24 hours contact); 1 mol/dm3 ammonium
acetate (6 hours contact); DTPA (0.005 mol/dm3 diethylenetriaminepentaacetic acid + 0.1
mol/dm3 triethanolamine + 0.01 mol/dm3 calcium chloride; 6 hours contact); and 10
mmol/dm3 of a mixture of low-molecular weight organic acids (acetic, lactic, citric, malic,
formic acids; molar ratio 4:2:1:1:1; 16 hours contact; rhizosphere-based method). The
availability of As has been assessed by extraction with 0.05 mol/dm3 ammonium
monophosphate (16 hours contact). All the extractions were performed using moist bulk soils
(< 2 mm fraction). Plants (roots and shoots) were analysed for the same elements. The
uptake and translocation of PHEs by plants was calculated. These results can be useful to
study the real hazard for biota posed by PHEs in soils polluted from mining areas. |
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