We analyzed the precipitation chemistry for a maritime region in northern Germany (Schleswig–Holstein) from 1997 to 2017 in order to reveal temporal and spatial patterns and to evaluate the role of meteorological factors relative to emission reductions in Germany and Europe. Therefore, we applied several statistical methods such as time series decomposition, principal component, and redundancy analysis. We extracted two main groups: (i) a marine group (Cl, Na, Mg) that was related to natural processes like sea spray input and (ii) an anthropogenic group (Pb, Cd, As, Zn, and nitrogen species) with a terrestrial subgroup (Fe, Al, Mn), which were both related to emissions. These groups were valid for the spatial, seasonal, and annual trend data. Other elements, like Ca, K, total P, and sulfate, were influenced by natural and anthropogenic processes. The seasonal variation of ammonium deposition was caused primarily by ammonia emissions and ancillary by precipitation. Most heavy metals as well as sulfate, nitrate, and ammonium showed decreasing trends in concentrations and deposition fluxes. Only Hg did not show any trend. The decreasing depositions of sulfate and total nitrogen were correlated to emission reductions in Germany. The deposition of most heavy metals was influenced by emission reductions on European scale and meteorological factors such as wind speed and humidity. Hg did not show any correlation with the emission time series in Europe. Instead, it was correlated to the NAO index and wind, implying that global emissions and transport pathways determine the temporal development of Hg depositions. Overall, the study reveals that emission reductions positively influence regional depositions for most investigated substances. The regional spatial patterns of depositions were also influenced by local meteorological factors.

我们分析了1997年至2017年德国北部（石勒苏益格–荷尔斯泰因州）海域的降水化学，以揭示时间和空间格局，并评估气象因素在德国和欧洲相对于减排的作用。因此，我们应用了几种统计方法，例如时间序列分解，主成分和冗余分析。我们提取了两个主要类别：（i）与诸如海浪输入等自然过程有关的海洋类别（Cl，Na，Mg），以及（ii）具有以下特征的人类活动类别（Pb，Cd，As，Zn和氮物种）：一个与排放有关的陆地亚组（Fe，Al，Mn）。这些组对于空间，季节和年度趋势数据有效。其他元素，例如钙，钾，总磷和硫酸盐，都受到自然和人为过程的影响。铵盐沉积的季节变化主要是由氨的排放引起的，而降水的辅助作用则是造成的。大多数重金属以及硫酸盐，硝酸盐和铵盐的浓度和沉积通量均呈下降趋势。只有汞没有显示任何趋势。硫酸盐和总氮减少的沉积与德国的排放减少有关。欧洲范围内的减排量以及诸如风速和湿度之类的气象因素影响了大多数重金属的沉积。汞与欧洲的排放时间序列没有任何相关性。取而代之的是，它与NAO指数和风有关，暗示着全球排放和运输途径决定了汞沉积的时间发展。全面的，研究表明，减少排放量对大多数被调查物质的区域沉积具有积极影响。沉积物的区域空间格局也受到当地气象因素的影响。