title: A classification and regression tree model of controls on dissolved inorganic nitrogen leaching from European forests.
abstract: Often, there is a non-linear relationship between atmospheric dissolved inorganic nitrogen (DIN) input and DIN leaching that is poorly captured by existing models. We present the first application of the non-parametric classification and regression tree approach to evaluate the key environmental drivers controlling DIN leaching from European forests. DIN leaching was classified as low (<3), medium (3-15) or high (>15kg N ha(-1) year(-1)) at 215 sites across Europe. The analysis identified throughfall NO(3)(-) deposition, acid deposition, hydrology, soil type, the carbon content of the soil, and the legacy of historic N deposition as the dominant drivers of DIN leaching for these forests. Ninety four percent of sites were successfully classified into the appropriate leaching category. This approach shows promise for understanding complex ecosystem responses to a wide range of anthropogenic stressors as well as an improved method for identifying risk and targeting pollution mitigation strategies in forest ecosystems.
authors.affiliation: Department of Environmental and Geographical Sciences, Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester M1 5GD, UK. j.j.rothwell@mmu.ac.uk
authors.forename: James J
authors.initials: JJ
authors.lastname: Rothwell
authors.forename: Martyn N
authors.initials: MN
authors.lastname: Futter
authors.forename: Nancy B
authors.initials: NB
authors.lastname: Dise
mesh_terms: D000327:Adsorption; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis*; D005060:Europe; D008954:Models, Biological; D015233:Models, Statistical; D009584:Nitrogen / Q000032:analysis*; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis; D014197:Trees
chemical_list: D004785:Environmental Pollutants; D012987:Soil; D012989:Soil Pollutants; D009584:Nitrogen