Thünen Institute of Forest Ecosystems, Alfred-Möller-Straße 1, Haus 41/42, Eberswalde, 16225, Germany; University of Göttingen, Department Silviculture and Forest Ecology of the Temperate Zones, Göttingen 37077, Germany.
Thünen Institute of Forest Ecosystems, Alfred-Möller-Straße 1, Haus 41/42, Eberswalde, 16225, Germany.
Environ Pollut. 2019 Jan;244:980-994. doi: 10.1016/j.envpol.2018.09.101. Epub 2018 Oct 26.
Average nitrogen (N) deposition across Europe has declined since the 1990s. This resulted in decreased N inputs to forest ecosystems especially in Central and Western Europe where deposition levels are highest. While the impact of atmospheric N deposition on forests has been receiving much attention for decades, ecosystem responses to the decline in N inputs received less attention. Here, we review observational studies reporting on trends in a number of indicators: soil acidification and eutrophication, understory vegetation, tree nutrition (foliar element concentrations) as well as tree vitality and growth in response to decreasing N deposition across Europe. Ecosystem responses varied with limited decrease in soil solution nitrate concentrations and potentially also foliar N concentrations. There was no large-scale response in understory vegetation, tree growth, or vitality. Experimental studies support the observation of a more distinct reaction of soil solution and foliar element concentrations to changes in N supply compared to the three other parameters. According to the most likely scenarios, further decrease of N deposition will be limited. We hypothesize that this expected decline will not cause major responses of the parameters analysed in this study. Instead, future changes might be more strongly controlled by the development of N pools accumulated within forest soils, affected by climate change and forest management.
欧洲的平均氮（N）沉积量自 20 世纪 90 年代以来一直在下降。这导致森林生态系统的 N 输入减少，特别是在沉积水平最高的中欧和西欧。尽管大气 N 沉积对森林的影响已经引起了数十年的关注，但对 N 输入减少的生态系统响应却受到较少关注。在这里，我们回顾了一些报告欧洲各地指示物趋势的观测研究：土壤酸化和富营养化、林下植被、树木营养（叶片元素浓度）以及树木活力和生长对减少 N 沉积的响应。生态系统的响应因土壤溶液硝酸盐浓度和叶片 N 浓度的有限下降而有所不同。林下植被、树木生长或活力没有大规模的响应。实验研究支持了这样的观察结果，即与其他三个参数相比，土壤溶液和叶片元素浓度对 N 供应变化的反应更为明显。根据最可能的情景，N 沉积的进一步减少将受到限制。我们假设，这种预期的下降不会导致本研究分析的参数发生重大变化。相反，未来的变化可能更受森林土壤中积累的 N 库的发展以及气候变化和森林管理的影响。
