Abstract

Keywords

Total nitrogen deposition,throughfall,Critical loads of nitrogen,Canopy uptake,dry deposition of nitrogen,forests

Abstract

Introduction: Nitrogen (N) gradient studies in some cases use N deposition in throughfall as measure of N deposition to forests. For evaluating critical loads of N, however, information on total N deposition is required, i.e., the sum of estimates of dry, wet and occult deposition.;Methods: The present paper collects a number of studies in Europe where throughfall and total N deposition were compared in different forest types. From this dataset a function was derived which allows to estimate total N deposition from throughfall N deposition.;Results: At low throughfall N deposition values, the proportion of canopy uptake is high and thus the underestimation of total deposition by throughfall N needs to be corrected. At throughfall N deposition values > 20 kg N ha–1 yr–1 canopy uptake is getting less important.;Conclusion: This work shows that throughfall clearly underestimates total deposition of nitrogen. With the present data set covering large parts of Europe it is possible to derive a critical load estimate from gradient studies using throughfall data.

LWF Classification

Network: LWF;deposition, Sites: Beatenberg;Bettlachstock;Celerina;Davos;Jussy;Lägeren;Nationalpark;Novaggio;Othmarsingen;Schänis;Visp;Vordemwald, Category: ISI,