Γεωχημικός άτλας της αστικής περιοχής του Λαυρίου για περιβαλλοντική προστασία και σχεδιασμό

Τόμος 1-2: Γεωχημικός άτλας της αστικής περιοχής του Λαυρίου για περιβαλλοντική προστασία και σχεδιασμόΤόμος 3: Περιβαλλοντικός χαρακτηρισμός περιοχής Λαυρίου - Ανάπτυξη τεχνικών αποκατάστασηςΤόμος 4: Περιβαλλοντικό σχέδιο διαχείρισης για την αποκατάσταση του εδάφους στην αστική περιοχή του Λαυρίο

GEMAS: establishing geochemical background and threshold for 53 chemical elements in European agricultural soil

The GEMAS (geochemical mapping of agricultural soil) project collected 2108 Ap horizon soil samples from regularly ploughed fields in 33 European countries, covering 5.6 million km2. The <2 mm fraction of these samples was analysed for 53 elements by ICP-MS and ICP-AES, following a HNO3/HCl/H2O (modified aqua regia) digestion. Results are used here to establish the geochemical background variation and threshold values, derived statistically from the data set, in order to identify unusually high element concentrations for these elements in the Ap samples. Potentially toxic elements (PTEs), namely Ag, B, As, Ba, Bi, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se, Sn, U, V and Zn, and emerging ‘high-tech’ critical elements (HTCEs), i.e., lanthanides (e.g., Ce, La), Be, Ga, Ge, In, Li and Tl, are of particular interest. For the latter, neither geochemical background nor threshold at the European scale has been established before. Large differences in the spatial distribution of many elements are observed between northern and southern Europe. It was thus necessary to establish three different sets of geochemical threshold values, one for the whole of Europe, a second for northern and a third for southern Europe. These values were then compared to existing soil guideline values for (eco)toxicological effects of these elements, as defined by various European authorities. The regional sample distribution with concentrations above the threshold values is studied, based on the GEMAS data set, following different methods of determination. Occasionally local contamination sources (e.g., cities, metal smelters, power plants, agriculture) can be identified. No indications could be detected at the continental scale for a significant impact of diffuse contamination on the regional distribution of element concentrations in the European agricultural soil samples. At this European scale, the variation in the natural background concentration of all investigated elements in the agricultural soil samples is much larger than any anthropogenic impact

GEMAS:adaptation of weathering indices for European agricultural soil derived from carbonate parent materials

Carbonate rocks are very soluble and export elements in dissolved form, and precipitation of secondary phases can occur on a large scale. They leave a strong chemical signature in soil that can be quantified and classified by geochemical indices, and which is useful for evaluating chemical weathering trends (e.g. the Chemical Index of Alteration (CIA) or the Mafic Index of Alteration (MIA)). Due to contrasting chemical compositions and high Ca content, a special adaptation of classical weathering indices is necessary to interpret weathering trends in carbonate-derived soil. In fact, this adaptation seems to be a good tool for distinguishing weathering grades of source-rock types at the continental scale, and allows a more robust interpretation of soil parent-material weathering grade and its impact on the current chemical composition of soil. An increasing degree of weathering results in Al enrichment and Mg loss in addition to Fe loss and Si enrichment, leaching of mobile cations such as Ca and Na, and precipitation of Fe-oxides and hydroxides. The relation between soil weathering status and its spatial distribution in Europe provides important information about the role played by climate and terrain. The geographical distribution of soil chemistry contributes to a better understanding of soil nutritional status, element enrichment, degradation mechanisms, desertification, soil erosion and contamination.</p

Use of GEMAS data for risk assessment of cadmium in European agricultural and grazing land soil under the REACH Regulation

Over 4000 soil samples were collected for the “Geochemical Mapping of Agricultural and Grazing Land Soil of Europe” (GEMAS) project carried out by the EuroGeoSurveys Geochemistry Expert Group. Cadmium concentrations are reported for the <2 mm fraction of soil samples from regularly ploughed fields (agricultural soil, Ap, 0 - 20 cm, N - 2218) and grazing land soil (Gr, 0 - 10 cm, N - 2127)

GEMAS: Boron as a geochemical proxy for weathering of European agricultural soil

About a century ago, B was recognised as an essential element for the normal growth of plants and terrestrial organisms. Limitations for plant development have been recognised in agricultural systems, particularly in highly weathered soil. Boron is rarely analysed in whole rock or soil analysis, as it requires specific analytical techniques. It is often determined, after partial extraction (aqua regia or Casingle bondCl), usually on a limited number of samples. Many more questions than answers exist about the environmental behaviour of B. We present B contents in agricultural soil samples (0–10 cm) collected in 33 European countries (5.6 million km2) during the GEMAS (GEochemical Mapping of Agricultural and grazing land Soil) continental-scale project. The B content, determined by ICP-MS following hot aqua regia extraction, varies in European agricultural soil from 0.5 to 49 mg/kg (median 2.42 mg/kg, n = 2108), which is somewhat similar to total B estimates for the Upper Continental Crust (17–47 mg/kg). Its spatial distribution in agricultural soil shows a patchy pattern with low values in regions with granitic bedrock and high contents in soil formed over limestone and in volcanic areas. Boron geochemical behaviour in soil is strongly dependent on other factors such as pH, CEC, presence of organic matter, clay and secondary oxides and hydroxides. Boron geochemical mapping at the continental scale in arable soil allows investigations of plant health, i.e., the beneficial and adverse effects due to the nutritional status of boron

Introduction

This comprehensive text focuses on the increasingly important issues of urban geochemical mapping with key coverage of the distribution and behaviour of chemicals and compounds in the urban environment. Clearly structured throughout, the first part of the book covers general aspects of urban chemical mapping with an overview of current practice and reviews of different aspects of the component methodologies. The second part includes case histories from different urban areas around Europe authored by those national or academic institutions tasked with investigating the chemical environments of their major urban centers

Geochemical atlas of European groundwater : bottled water

Analysis of natural bottled mineral water (usually derived from untreated ground water) can provide a first impression of ground water chemistry at the European scale. For this study, 1785 bottled water samples were purchased from supermarkets, representing 1247 wells/springs/boreholes at 884 locations. These were analysed for 72 parameters by a variety of methods. A very strict quality control programme was followed to ensure results of high standard that are presented as a geochemical atlas. These give a first impression of European ground water geochemistry. Many processes are seen to affect the hydrogeochemical fingerprint of ground water, including rainfall chemistry, climate, vegetation and soil zone processes, mineral-water interactions, ground water residence time and the mineralogy and chemistry of the aquifer (and contamination). It appears that geology is the major factor controlling the content and distribution for the majority of elements in bottled water samples. However, knowledge of geology alone is inadequate to predict the hydrogeochemistry of bottled water. A key observation is that natural variation is enormous, usually three to four and for some elements up to seven orders of magnitude. It has also been found that bottle materials can have an influence on bottled water chemistry. For example, leaching of Sb from the bottle material is so serious that the results cannot be used as an indication of natural concentration in ground water. Very few analysed samples (in general <1%) returned values exceeding maximum admissible concentrations for “mineral water”, as defined by the European Commission