Does spatial auto-correlation call for a revision of latest heavy metal and nitrogen deposition maps?

As already published, the regression models corroborated significant correlations between the concentrations of heavy metals and nitrogen in atmospheric depositions on the one hand and respective concentrations in mosses on the other hand. This investigation proved that atmospheric deposition and bioaccumulation data are spatially auto-correlated significantly in terms of Moran’s I values and, thus, hypothesis 1 could be rejected. Accordingly, the degrees of freedom were reduced. Nevertheless, the results of the calculations regarding the reduced degrees of freedom indicate that the statistical relations between atmospheric depositions and bioaccumulations remained statistically significant so that hypothesis 2 could be rejected, too.The positive auto-correlation in data on atmospheric deposition and bioaccumulation does not call for a revision of the 5？km by 5？km deposition maps published in recent papers. Therefore we can conclude that the European moss monitoring yields data that support the validation of modelling and mapping of atmospheric depositions of heavy metals and nitrogen at a high spatial resolution compared to the 50？km x 50？km EMEP maps.Measurements of atmospheric depositions are needed as a basis to evaluate environmental quality. To this end, deposition data are, amongst others, used to calculate exceedance maps for critical loads. Critical loads are defined as quantitative estimates of an exposure to one or more pollutants below which significant harmful effects on specified ecosystem functions are not expected to occur according to present knowledge [1]. In Europe, the control of heavy metals and reactive nitrogen emissions to air is regulated under several directives of the European Union and protocols of the Long-range Transboundary Air Pollution (LRTAP) Convention. Under the LRTAP Convention, the European Monitoring and Evaluation Programme (EMEP) collects emission data from European countries in order to model atmospheric transport and deposi