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Werner Kratz 《Environmental Sciences Europe》1996,8(3):130-137
Atmospheric heavy metals, (Pb, Cd, Cu, Zn), PAHs, and PCBs, depositions were monitored in scots pine needles during a monitoring network programme (Monitoring Programme Natural Budget Berlin and Environs) in 1991 in the city of Berlin, and the surrounding rural areas of Brandenburg (Germany). The total area of the network covered 3,000 km2. The passive monitoring technique is based on the fact that the concentrations of heavy metals, PAH’s and PCB’s in the needles are closely correlated to atmospheric depositions/emissions. The objectives of the project were to characterize qualitatively and quantitatively the regional atmospheric deposition patterns of heavy metals, PAH’s and PCB’s in rural and polluted urban areas of Berlin and Brandenburg. The indication of the locations which could be characterized as heavy metals, PAH and PCB pollution sources was also targetted in this investigation. After conclusion, comparison with similar studies conducted in different parts of Germany and Europe would be possible. The regional background deposition levels showed different distribution patterns. The lead and PAH concentrations in the pine needles were closely correlated to the locations of combustion sources petrol, oil, brown coal and heavy traffic activities. The PCB and cadmium concentration levels in the pine needles represented a more ubiquitous distribution pattern. 相似文献
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Biotic and abiotic factors involved in surface coal mine reclamation were evaluated on 81 mine sites in Mercer County, Pennsylvania, USA. Soil moisture and organic content were the two most important factors in determining the establishment and growth of vegetation on mined lands. Soil bacteria and fungi populations were also related to these soil conditions, and soil micro-organisms were important in the decomposition of organic materials as well as factors in the rate and type of natural succession occurring on these lands. The succession of native plant species increases the density and stability of plant communities on mined lands. The importance of natural succession in mined-land reclamation and the use of these lands by wildlife is discussed.Supported by Grant-In-Aid, Natural Geographic Society. 相似文献
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