摘要
Mountain lakes are usually sensitive to the effects of global and regional environmental changes. Since the second half of the 20 th century, surface-water acidification has become a significant ecological problem, and many lakes in Europe and North America have anthropogenically acidified. Additionally, following reduction in emissions of sulfur（S） and nitrogen（N） compounds, recovery from acidification has been observed in many lakes. In this study, we used changes in diatom communities to reconstruct the p H histories based on changes recorded in nine Tatra lakes（Western Carpathians, Poland） since approximately1850 AD. Overall, results indicate that acidic precipitation had little influence on lake-water p H in the Tatra Mountain lakes. Changes in diatom-inferred p H（DI-p H） generally were small and showed little evidence of acidification during the time of the highest air pollution（since the 1960 s）, and have shown little change since the reduction of acidic deposition since the 1990 s. Lakes that showed some evidence of acidification included dystrophic lakes with low acid neutralizing capacity. However, as illustrated by the PCA trajectories of the diatom assemblages, the majority of the lakes currently contain diatom assemblages that are unlike the diatom floras that existed ca. 1850.
Mountain lakes are usually sensitive to the effects of global and regional environmental changes. Since the second half of the 20 th century, surface-water acidification has become a significant ecological problem, and many lakes in Europe and North America have anthropogenically acidified. Additionally, following reduction in emissions of sulfur（S） and nitrogen（N） compounds, recovery from acidification has been observed in many lakes. In this study, we used changes in diatom communities to reconstruct the p H histories based on changes recorded in nine Tatra lakes（Western Carpathians, Poland） since approximately1850 AD. Overall, results indicate that acidic precipitation had little influence on lake-water p H in the Tatra Mountain lakes. Changes in diatom-inferred p H（DI-p H） generally were small and showed little evidence of acidification during the time of the highest air pollution（since the 1960 s）, and have shown little change since the reduction of acidic deposition since the 1990 s. Lakes that showed some evidence of acidification included dystrophic lakes with low acid neutralizing capacity. However, as illustrated by the PCA trajectories of the diatom assemblages, the majority of the lakes currently contain diatom assemblages that are unlike the diatom floras that existed ca. 1850.
基金
supported by grant no.N N306 077436 from the Polish National Science Centre
