title: Nitrogen deposition to forest ecosystems with focus on its different forms.
abstract: Time trends and spatial patterns for wet nitrogen deposition in view of its reduced and oxidized forms for Czech forests are presented. Time trends in NH4+, NO3-, and N-NH4+/N-NO3-ratio at 15 sites in 1990-2014 were analysed using the Mann-Kendal test. Changes in spatial patterns derived from results of 43 sites in 2005-2014 were also assessed. Our results indicated a slow but convincing change in favour of NH4+. The N-NH4+/N-NO3-ratio, both in precipitation and wet deposition, has been increasing steadily, reflecting the changes in reduced and oxidized forms of nitrogen emissions. A similar change has been observed in some other regions and might have negative impacts on ecosystems.
  N-NH4+/N-NO3-ratio in precipitation and deposition changes in favour of NH4+. This reflects changes in emissions and might have implications for ecosystems.
authors.affiliation: Czech Hydrometeorological Institute, Prague, Czech Republic; Charles University in Prague, Faculty of Science, Institute for Environmental Studies, Czech Republic. Electronic address: hunova@chmi.cz.
authors.forename: I
authors.initials: I
authors.lastname: Hůnová
authors.affiliation: Czech Hydrometeorological Institute, Prague, Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Kurfürst
authors.affiliation: Czech Hydrometeorological Institute, Prague, Czech Republic; Charles University in Prague, Faculty of Science, Institute for Environmental Studies, Czech Republic.
authors.forename: V
authors.initials: V
authors.lastname: Stráník
authors.affiliation: Czech Hydrometeorological Institute, Prague, Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Modlík
keywords: Atmospheric deposition; Emissions; Forests; Oxidized nitrogen; Reduced nitrogen