title: Environmental assessment of potential toxic trace element contents in the inundated floodplain area of Tablas de Daimiel wetland (Spain).
abstract: Contamination of aquatic systems with potentially toxic trace elements (PTEs) is a major problem throughout the world. The National Park Tablas de Daimiel (NPTD) is considered to make up one of the two most important wetlands in the Biosphere Reserve called "Wet Spot." Since PTEs are good indicator of the prevailing environmental conditions and possible contamination, soil samples collected from 43 sites were analyzed in order to investigate the levels and its distribution of these elements, in the inundated floodplain area of the NPTD wetland. In addition, some physicochemical parameters such as pH, electrical conductivity and organic matter were measured. The total concentrations of 32 trace elements were determined by X-ray fluorescence. The results show that there was accumulation of lead (Pb), tin (Sn), selenium (Se), antimony (Sb), copper (Cu), vanadium (V), nickel (Ni), zinc (Zn), arsenic (As), strontium (Sr) and zirconium (Zr)-in some cases at high concentrations. The interpolated maps showed that the distributions of some of these elements and in some cases the trend in spatial variability are pronounced and decrease from the inlet to the outlet. The values for some elements are higher than the reference values, which is consistent with contamination (some values are higher by a factor of more than 10 compared to the reference). In the case of iodine (I), the levels at some sample points are significantly more than ten times the reference; Se appears in the range from 1.0 to 9.8 mg/kg, with an average value of 3.1 mg/kg, and these can be considered as seleniferous soils. The concentrations found are consistent with the introduction in the wetland of pollution by human activities, such as agricultural non-point sources, uncontrolled fertilization over many years, treatment with urban wastewater and other possible sources.
authors.affiliation: Department of Geology and Geochemistry, Universidad Autónoma, 28049, Madrid, Spain. raimundo.jimenez@uam.es.
authors.forename: R
authors.initials: R
authors.lastname: Jiménez-Ballesta
authors.affiliation: Escuela de Ingenieros Agrónomos, Universidad de Castilla La Mancha, 13071, Ciudad Real, Spain.
authors.forename: F J
authors.initials: FJ
authors.lastname: García-Navarro
authors.affiliation: Escuela de Ingenieros Agrónomos, Universidad de Castilla La Mancha, 13071, Ciudad Real, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Bravo
authors.affiliation: Escuela de Ingenieros Agrónomos, Universidad de Castilla La Mancha, 13071, Ciudad Real, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Amorós
authors.affiliation: Escuela de Ingenieros Agrónomos, Universidad de Castilla La Mancha, 13071, Ciudad Real, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Pérez-de-Los-Reyes
authors.affiliation: Geological Survey of Spain, 28003, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Mejías
mesh_terms: D004784:Environmental Monitoring; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain; D014131:Trace Elements / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
chemical_list: D012989:Soil Pollutants; D014131:Trace Elements; D014874:Water Pollutants, Chemical
keywords: Fertilization; Potentially toxic trace elements; Spatial variability; Tablas de Daimiel National Park; Wastewater; Wetland