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Under the Convention on Long-Range Transboundary Air Pollution (CLRTAP) of the UN Economic Commission for Europe, UNECE, to which Germany acceded in 1982, the harmful effects of air pollutants on the environment are to be steadily reduced and ultimately limited to a level that is compatible with nature. The ICP Modelling & Mapping (ICP M&M) under the Working Group on Effects (WGE) of CLRTAP maps critical loads for the entire Convention area and calculates the exceedance risks and associated risks to vegetation and biodiversity. A current data request was made in November 2015 with the aim of submitting new or updated ecosystem-specific critical loads for protection against acidification and eutrophication. For this task, critical loads were determined by the authors for one third of the territory of Germany using the simple mass balance (SMB) method according to the ICP Mapping Manual. The permissible eutrophying nitrogen input into the ecosystem CLnut(N), as well as the acidifying sulphur input CLmaxS, can be described as the setting of the equilibrium between substance inputs and outputs, provided that specific critical limits are met. The BERN database—created by the authors—serves as the basis for modelling vegetation-specific critical limits as a complement to the SMB model. The BERN database contains near-natural plant communities with clearly definable site constancy. The 25,600 German and a further 24,600 European vegetation records dating back to before 1960 were evaluated to determine the good ecological status of the plant communities. The results of the critical load calculation show that about half of the receptor areas have critical loads for eutrophying nitrogen below 10 kg ha−1 a−1 and critical loads for acidifying sulphur were below 1500 eq ha−1 a−1. It could be demonstrated that the BERN–SMB-modelled critical loads for eutrophying nitrogen inputs show lower values on average throughout Germany than those calculated using only the previous critical limits according to the ICP Mapping Manual. These values are closer to the empirical critical loads than the critical loads without BERN data. For the goal of the German National Biodiversity Strategy by 2007 and 2020 to define ecosystem-related impact thresholds for pollutants that describe the effects on biodiversity, the BERN/SMB critical loads for the protection of ecosystems provide a precautionary scientific basis. [ABSTRACT FROM AUTHOR]

The protection against eco- and human-toxicological impairments caused by atmospheric deposition of heavy metals requires legally defined assessment values. Since such values are missing for Luxembourg, the aim of this investigation was to evaluate different approaches to derive assessment values for the regulation of heavy metals that are in accordance with scientific and legal standards. To this end, assessment values for heavy metals were derived from the compilation of respective values implemented in European countries. In addition, (1) precipitation-related assessment values for the protection of soil for Cr, Zn, and Cu and (2) precautionary assessment values (critical loads for Cr, Zn, and Cu, as well as As, Cd, Ni, and Pb) for the protection of human health and ecosystems were calculated. The calculation of the regionally differentiated precipitation-related assessment values resulted in ranges of 17–272 g Cu ha−1 a−1, 167–2672 g Zn ha−1 a−1 and 17–272 g Crtotal ha−1 a−1. The critical loads for drinking water protection vary in the ranges from 1.23 to 2.14 g Cd ha−1 a−1, from 4.05 to 8.63 g Pb ha−1 a−1, from 2.6 to 5.9 g As ha−1 a−1, from 258 to 564 g Cu ha−1 a−1, from 1292 to 2944 g Zn ha−1 a−1, and from 12.9 to 29.9 g Crtotal ha−1 a−1. Ecosystems are significantly more sensitive to Pb, Cu, and Zn inputs than humans. For As and Cr, humans react much more sensitively than ecosystems. For Cd, the critical loads for drinking water, ecosystems, and wheat products are about the same. [ABSTRACT FROM AUTHOR]

Tailored intensity profiles within the focal spot of the laser beam offer great potential for a well-defined control of the interaction process between laser radiation and material, and thus for improving the processing results. The present paper discusses a novel refractive beam-shaping element that provides different squared intensity distributions converted from the Gaussian output beam of the utilized femtosecond (fs) laser. Using the examples of surface structuring of stainless-steel on the micro- and nano-scale, the suitability of the beam-shaping element for fs-laser material processing with a conventional f-Theta lens is demonstrated. In this context, it was shown that the experimental structuring results are in good agreement with beam profile measurements and numerical simulations of the beam-shaping unit. In addition, the experimental results reveal the improvement of laser processing in terms of a significantly reduced processing time during surface nano-structuring and the possibility to control the ablation geometry during the fabrication of micro-channels. [ABSTRACT FROM AUTHOR]

Deposition of N and heavy metals can impact ecological and human health. This state-of-the-art review addresses spatial and temporal trends of atmospheric deposition as monitored by element accumulation in moss and compares heavy metals Critical Loads for protecting human health and ecosystem's integrity with modelled deposition. The element accumulation due to deposition was measured at up to 1026 sites collected across Germany 1990–2015. The deposition data were derived from chemical transport modelling and evaluated with regard to Critical Loads published in relevant legal regulations. The moss data indicate declining nitrogen and HM deposition. Ecosystem and human health Critical Loads for As, Ni, Zn, and Cr were not exceeded in Germany 2009–2011. Respective Critical Loads were exceeded by Hg and Pb inputs, especially in the low rainfall regions with forest coverage. The Critical Load for Cu was exceeded by atmospheric deposition in 2010 in two regions. Human health Critical Loads for Cd were not exceeded by atmospheric deposition in 2010. However, the maximum deposition in 2010 exceeded the lowest human health Critical Load. This impact assessment was based only on deposition but not on inputs from other sources such as fertilizers. Therefore, the assessment should be expanded with regard to other HM sources and specified for different ecosystem types. [ABSTRACT FROM AUTHOR]