Emissions and removals of greenhouse gases from land use, land use change and forestry (LULUCF) for England,Scotland, Wales and Northern Ireland: 1990�2011

[摘要] Historical mining activity has in some cases released large quantities of heavy metals into the fluvial environment of many settings around the world. County Antrim is one of the main areas in Northern Ireland known for historical mining, where 780 shafts and adits are associated with iron ore exploration, and where historically, ca. 700,000 tonnes of bauxite were produced. In order to assess the legacy of mining operations, it is important to understand the present (baseline) chemistry of the natural environment. Heavy metals resulting from mining activities need to be distinguished from products of natural variation and geological processes. Using geographic information systems (GIS) and multi-element diagrams ("spidergrams") for analysis, the project modelled the geological background of the area, and was able to distinguish whether high metal concentrations in stream sediments were of mining or of natural origin. Sub-catchments with enhanced sediment element concentrations relative to the geological background were identified; and enrichment factors (EFs), as a classification of the degree of enhancement above natural geological background due to mining activities, were calculated. Results of this study reveal that stream sediment compositions are mainly determined by the underlying geology. Sediment quality guidelines for As, Cd, Cu, Pb and Zn were exceeded by

[发布机构] NERC/Centre for Ecology & Hydrology

[效力级别] Atmospheric Sciences