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- ItemThe use of matrix-specific calibrations for oxygen in analytical glow discharge spectrometry(Dordrecht : Springer, 2014) Gonzalez-Gago, C.; Smid, P.; Hofmann, T.; Venzago, C.; Hoffmann, V.; Gruner, W.The performance of glow discharge optical emission spectroscopy and mass spectrometry for oxygen determination is investigated using a set of new conductive samples containing oxygen in the percent range in three different matrices (Al, Mg, and Cu) prepared by a sintering process. The sputtering rate corrected calibrations obtained at standard conditions for the 4 mm anode (700 V, 20 mA) in GD-OES are matrix independent for Mg and Al but not for Cu. The importance of a "blue shifted" line of oxygen at 130.22 nm (first reported by Köster) for quantitative analyses by GD-OES is confirmed. Matrix-specific calibrations for oxygen in GD-MS are presented. Two source concepts - fast flow (ELEMENT GD) and low gas flow (VG9000) - are evaluated obtaining higher sensitivity with the static flow source. Additional experiments using Ar-He mixtures or μs pulsed GD are carried out in ELEMENT GD aiming to improve the oxygen sensitivity.
- ItemEffects of Climate Change on the Hydrological Cycle in Central and Eastern Europe(Dordrecht : Springer, 2014) Stagl, J.; Mayr, E.; Koch, H.; Hattermann, F.F.; Huang, S.For the management of protected areas knowledge about the water regime plays a very important role, in particular in areas with lakes, wetlands, marches or floodplains. The local hydrological conditions depend widely on temporal and spatial variations of the main components of the hydrologic cycle and physiographic conditions on site. To preserve a favourable conservation status under changing climatic conditions park managers require information about potential impacts of climate change in their area. The following chapter provides an overview of how climate change affects the hydrological regimes in Central and Eastern Europe. The hydrological impacts for the protected areas are area-specific and vary from region to region. Generally, an increase in temperature enhances the moisture holding capacity of the atmosphere and thus, leads to an intensification of the hydrological cycle. Key changes in the hydrological system include alterations in the seasonal distribution, magnitude and duration of precipitation and evapotranspiration. This may lead to changes in the water storage, surface runoff, soil moisture and seasonal snow packs as well as to modifications in the mass balance of Central European glaciers. Partly, water resources management can help to counterbalance effects of climate change on stream flow and water availability.
- ItemClimate Change in Central and Eastern Europe(Dordrecht : Springer, 2014) Anders, I.; Stagl, J.; Auer, I.; Pavlik, D.Climate change is affecting many fields of the society, policy, economy and environment. Information on changes in the climate during the last centuries and especially in near and far future is essential. Estimation and quantification of changes in climate variables and indices are a necessary precondition for adaptation and mitigation measures. This chapter gives an overview on measures, observations as well as dynamical models, which are available to estimate changes in the past and the present climate as well as for a possible future climate. It summarises the state of knowledge according to the climate change signal in Central and Eastern Europe. Moreover it identifies the limitations and uncertainties of the measures and the derived information.
- ItemClimate Change Impact Modelling Cascade – Benefits and Limitations for Conservation Management(Dordrecht : Springer, 2014) Vohland, K.; Rannow, S.; Stagl, J.Model results can serve as a basis for adaptation in conservation management. They can help understanding the impact of climate change, and support the formulation of management measures. However, model results rely strongly on the quality and the resolution of the input data; they contain significant uncertainties and need to be interpreted in the context of the modelling assumptions. The perception of models and their results differs between disciplines as well as between science and practice. Part of this gap derives from the long ‘model cascade’ used for the assessment of climate related impacts on biodiversity. For this ‘model cascade’ model results from Global Climate Models are often used to drive Regional Downscaled Climate Models and are transferred to hydrological models or distribution models of plants and animals. In fact, most assessments of potential impacts of climate change on biodiversity rely on habitat modelling of plants and animals. But, only few decision makers are trained to analyse the different outcomes of climate impact modelling. If modelling is integrated into conservation management it must be based on an evaluation of the need for information in protected areas and an assessment of model use in the management process, so as to guarantee maximum usability.
- ItemMeasurements of PM10 ions and trace gases with the online system MARGA at the research station Melpitz in Germany – A five-year study(Dordrecht : Springer, 2017) Stieger, B.; Spindler, G.; Fahlbusch, B.; MĂ¼ller, K.; GrĂ¼ner, A.; Poulain, L.; Thöni, L.; Seitler, E.; Wallasch, M.; Herrmann, H.An hourly quantification of inorganic water-soluble PM10 ions and corresponding trace gases was performed using the Monitor for AeRosols and Gases in ambient Air (MARGA) at the TROPOS research site in Melpitz, Germany. The data availability amounts to over 80% for the five-year measurement period from 2010 to 2014. Comparisons were performed for the evaluation of the MARGA, resulting in coefficients of determinations (slopes) of 0.91 (0.90) for the measurements against the SO2 gas monitor, 0.84 (0.88), 0.79 (1.39), 0.85 (1.20) for the ACSM NO3 −, SO4 2− and NH4 + measurements, respectively, and 0.85 (0.65), 0.88 (0.68), 0.91 (0.83), 0.86 (0.82) for the filter measurements of Cl−, NO3 −, SO4 2− and NH4 +, respectively. A HONO comparison with a batch denuder shows large scatter (R2 = 0.41). The MARGA HNO3 is underestimated compared to a batch and coated denuder with shorter inlets (slopes of 0.16 and 0.08, respectively). Less NH3 was observed in coated denuders for high ambient concentrations. Long-time measurements show clear daily and seasonal variabilities. Potential Source Contribution Function (PSCF) analysis indicates the emission area of particulate ions Cl−, NO3 −, SO4 2−, NH4 +, K+ and gaseous SO2 to lie in eastern European countries, predominantly in wintertime. Coarse mode sea salt particles are transported from the North Sea to Melpitz. The particles at Melpitz are nearly neutralised with a mean molar ratio of 0.90 for the five-year study. A slight increase of the neutralization ratio over the last three years indicates a stronger decrease of the anthropogenically emitted NO3 − and SO4 2− compared to NH4 +.
- ItemUsing Meta-Analysis and GIS for Value Transfer and Scaling Up: Valuing Climate Change Induced Losses of European Wetlands(Dordrecht : Springer, 2012) Brander, L.M.; Bräuer, I.; Gerdes, H.; Ghermandi, A.; Kuik, O.; Markandya, A.; Navrud, S.; Nunes, P.A.L.D.; Schaafsma, M.; Vos, H.; Wagtendonk, A.There is growing policy and academic interest in transferring ecosystem service values from existing valuation studies to other ecosystem sites at a large geographic scale. Despite the evident policy demand for this combined transfer and "scaling up" of values, an approach to value transfer that addresses the challenges inherent in assessing ecosystem changes at a national or regional level is not available. This paper proposes a methodology for scaling up ecosystem service values to estimate the welfare effects of ecosystem change at this larger geographical scale. The methodology is illustrated by applying it to value the impact of climate change on European wetlands for the period 2000-2050. The proposed methodology makes use of meta-analysis to produce a value function. The parameters of the value function include spatial variables on wetland size and abundance, GDP per capita, and population. A geographic information system is used to construct a database of wetland sites in the case study region with information on these spatial variables. Site-specific ecosystem service values are subsequently estimated using the meta-analytic value function. The proposed method is shown to enable the adjustment of transferred values to reflect variation in important spatial variables and to account for changes in the stock of ecosystems.
- ItemNeurodynamic evaluation of hearing aid features using EEG correlates of listening effort(Dordrecht : Springer, 2017) Bernarding, Corinna; Strauss, Daniel J.; Hannemann, Ronny; Seidler, Harald; Corona-Strauss, Farah I.In this study, we propose a novel estimate of listening effort using electroencephalographic data. This method is a translation of our past findings, gained from the evoked electroencephalographic activity, to the oscillatory EEG activity. To test this technique, electroencephalographic data from experienced hearing aid users with moderate hearing loss were recorded, wearing hearing aids. The investigated hearing aid settings were: a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off, and a setting using omnidirectional microphones without any noise reduction. The results suggest that the electroencephalographic estimate of listening effort seems to be a useful tool to map the exerted effort of the participants. In addition, the results indicate that a directional processing mode can reduce the listening effort in multitalker listening situations.