COMBUSTION AND LEACHING BEHAVIOR OF TRACE ELEMENTS IN LIGNITE AND COMBUSTION BY-PRODUCTS FROM THE MUĞLA BASIN, SW TURKEY

The Muğla Basin is one of the most well-documented coal basins of Anatolia, SW Turkey. Previous studies mainly focused on coal geology, as well as on the environmental impacts from trace elements emitted into the atmosphere during coal combustion. However, the environmental impacts from coal utilization also include groundwater contamination from hazardous trace elements leached from exposed lignite stockpiles or ash disposal dumps. In the present study a comparative assessment of the combustion, as well as the leaching behaviour of trace elements from sixteen lignite, fly ash and bottom ash samples under various pH conditions is attempted. The samples were picked up from three regions in the Muğla Basin, namely, these of Yeniköy, Kemerköy and Yatağan. Proximate and ultimate analyses were performed on all samples. Quantitative mineralogical analysis was carried out using a Rietveld-based full pattern fitting technique. The elements Ag, As, B, Ba, Be, Co, Cr, Cu, Fe, Ga, Hf, Li, Mn, Mo, Ni, Pb, Sr, U, V and Zn were grouped according to their volatility during combustion and their leachability in the various types of samples. The pH of the leaching agent little affected the leaching trends of most elements and the mode of occurrence proved to be the major factor controlling primarily combustion and to a lesser extent leaching. The elements were classified into 7 classes with increasing environmental significance with Mo, Sr and V being the most potentially hazardous trace elements in the Muğla region

Vertical zonation of testate amoebae in the Elatia Mires, northern Greece : palaeoecological evidence for a wetland response to recent climate change or autogenic processes?

The Elatia Mires of northern Greece are unique ecosystems of high conservation value. The mires are climatically marginal and may be sensitive to changing hydroclimate, while northern Greece has experienced a significant increase in aridity since the late twentieth century. To investigate the impact of recent climatic change on the hydrology of the mires, the palaeoecological record was investigated from three near-surface monoliths extracted from two sites. Testate amoebae were analysed as sensitive indicators of hydrology. Results were interpreted using transfer function models to provide quantitative reconstructions of changing water table depth and pH. AMS radiocarbon dates and 210Pb suggest the peats were deposited within the last c. 50 years, but do not allow a secure chronology to be established. Results from all three profiles show a distinct shift towards a more xerophilic community particularly noted by increases in Euglypha species. Transfer function results infer a distinct lowering of water tables in this period. A hydrological response to recent climate change is a tenable hypothesis to explain this change; however other possible explanations include selective test decay, vertical zonation of living amoebae, ombrotrophication and local hydrological change. It is suggested that a peatland response to climatic change is the most probable hypothesis, showing the sensitivity of marginal peatlands to recent climatic change

The peatland map of Europe

Based on the ‘European Mires Book’ of the International Mire Conservation Group (IMCG), this article provides a composite map of national datasets as the first comprehensive peatland map for the whole of Europe. We also present estimates of the extent of peatlands and mires in each European country individually and for the entire continent. A minimum peat thickness criterion has not been strictly applied, to allow for (often historically determined) country-specific definitions. Our ‘peatland’ concept includes all ‘mires’, which are peatlands where peat is being formed. The map was constructed by merging national datasets in GIS while maintaining the mapping scales of the original input data. This ‘bottom-up’ approach indicates that the overall area of peatland in Europe is 593,727 km². Mires were found to cover more than 320,000 km² (around 54 % of the total peatland area). If shallow-peat lands (< 30 cm peat) in European Russia are also taken into account, the total peatland area in Europe is more than 1,000,000 km2, which is almost 10 % of the total surface area. Composite inventories of national peatland information, as presented here for Europe, may serve to identify gaps and priority areas for field survey, and help to cross-check and calibrate remote sensing based mapping approaches

Geological factors influencing the concentration of trace elements in the Philippi peatland, eastern Macedonia, Greece

17 páginas, 4 figuras, 5 tablas.Six peat samples obtained from the Holocene and the Weichselian of the Philippi peat deposit, eastern Macedonia, Greece, were analyzed for 48 trace elements by Inductively Coupled Plasma–Mass Spectrometry (ICP–MS). The ash contents of these samples were also determined. Most of the trace elements are associated with the minerals in the peat, while Ge, Mo, Pb, Se, Ta, Tl, U, and W display a greater affinity with the organic matter. Compared with crustal averages (Clarke concentrations), the Philippi peat is enriched in some elements (Ag, As, Au, Cd, Mo, Se, Te, U, and W) because of the respective mineralizations in the area. The Philippi peat is also enriched in Cr, Cu, Mo, Pb, Sc, Sn, T, V, Y, and Zn in comparison with typical fen peats, as well as in As, Cr, Mo, Se, and U in comparison with typical coals. Climatic and hydrogeological conditions strongly influenced the peat-forming environment resulting in a differentiation between Holocene and Weichselian peat. Generally, the Holocene peat contains lower concentrations of trace elements in the northern and southern part of the fen, than the Weichselian one. The opposite trend is observed in the fen area close to the western basin margins.Peer reviewe