Trends in Surface Water Acidification in Europe and North America (1989–1998)

摘要: During the last 20 years, emission reductions in Europe and North America have resulted decreased atmospheric S-deposition of up to 50%, while N-deposition has stayed almost constant. Data from 98 ICP Waters sites were tested for trends concentrations major chemical components 10-year period 1989-1998 using nonparametric seasonal Kendall test. The grouped into regions types meta-analysis. All had highly significant downward SO4 2−* concentrations. Nitrate concentrations, on other hand, show no regional patterns change. Concentrations base cations declined most regions. showed tendencies increasing DOC. low ANC largest rates recovery. Neither high NO3 − or groups exhibited Alpine (non-forested) clear consistent signals recovery pH, appropriate (relative trends) cation decline.