An assessment of pollution impacts due to the oil and gas industries in the Pechora basin, north-eastern European Russia

The chemical composition of terricolous lichens, top-soil and abundance and diversity of lichen communities were assessed at eight sites in the Pechora basin during the summer of 2000 and 2001 to assess local impacts of oil and gas operations. Sites close to industrial areas were compared with areas considered to be pristine. The broad objective of the study was to identify changes in the chemistry of a suite of lichens that could be caused by pollutants from the industrial sites. In particular, increases in the ratios of K:Mg and K:Ca + Mg are indicators of acid deposition and increased N indicates increased N deposition. Lead was also measured in lichens. Other elements measured were Ba, Ca, Cd, Cu, K, Mg, Na, Ni, Pb, Sr and Zn in top-soils. The Pechora basin, north-eastern European Russia, includes the north and east of the Komi Republic and a major portion of the Nenets Autonomous region. It is bounded by the Ural mountains to the east and by the Timan range to the west. The area has extensive natural resources, both renewable (e.g. forests) and non-renewable (e.g. minerals, coal, oil and gas). There were limited modifications in the chemistry of lichens and top-soils and lichen diversity close to an oil and gas industrial complex. Here, there were elevations of lead and nitrogen concentrations in lichen apices and in the apical:basal nitrogen ratio in Flavocetraria cucullata, with lower lichen diversity in epigeal and epiphytic lichens. Elevated concentrations of Ba and Ca were found in soil-ash over the 0-5 cm horizon, probably as a result of local emissions from construction activity and gas flaring, rather than from long-range transport. Virtually all other sites remained unmodified and reflected background concentrations. The ecological impacts of the measured pollution loads were low, as elemental concentrations were generally below detection limits, except for one industrial site, where there were signs of an early indicator of industrial activity. (c) 2005 Elsevier Ltd. All rights reserved.