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In initial ecosystems concentrations of all macro- and micronutrients can be considered as extremely low. Plant litter therefore strongly influences the development of a degraders' food web and is an important source for C and N input into soil in such ecosystems. In the present study, a ¹³C litter decomposition field experiment was performed for 30 weeks in initial soils from a post-mining area near the city of Cottbus (Germany). Two of this regions' dominant but contrasting pioneering plant species (<i>Lotus corniculatus</i> L. and <i>Calamagrostis epigejos</i> L.) were chosen to investigate the effects of litter quality on the litter decomposing microbial food web in initially nutrient-poor substrates. The results clearly indicate the importance of litter quality, mainly the amount of N stored in the litter material and its bioavailability for the degradation process and the development of microbial communities in the detritusphere and bulk soil. Whereas the degradation process of the <i>L. corniculatus</i> litter which had a low C/N ratio was fast and most pronounced changes in the microbial community structure were observed 1–4 weeks after litter addition, the degradation of the <i>C. epigejos</i> litter material was slow and microbial community changes mainly occurred at between 4 and 30 weeks after litter addition to the soil. However for both litter materials a clear indication for the importance of fungi for the degradation process was observed both on the abundance level as well as on the level of ¹³C incorporation (activity)

In initial ecosystems, concentrations of all macro- and micronutrients can be considered as extremely low. Plant litter therefore strongly influences the development of a degrader's food web and is an important source for C and N input into soil in such ecosystems. In the present study, a ¹³C litter decomposition field experiment was performed for 30 weeks in initial soils from a post-mining area near the city of Cottbus (Germany). Two of this region's dominant but contrasting pioneering plant species (Lotus corniculatus L. and Calamagrostis epigejos L.) were chosen to investigate the effects of litter quality on the litter decomposing microbial food web in initially nutrient-poor substrates. The results clearly indicate the importance of litter quality, as indicated by its N content, its bioavailability for the degradation process and the development of microbial communities in the detritusphere and soil. The degradation of the L. corniculatus litter, which had a low C / N ratio, was fast and showed pronounced changes in the microbial community structure 1–4 weeks after litter addition. The degradation of the C. epigejos litter material was slow and microbial community changes mainly occurred between 4 and 30 weeks after litter addition to the soil. However, for both litter materials a clear indication of the importance of fungi for the degradation process was observed both in terms of fungal abundance and activity (¹³C incorporation activity

SummaryWe studied the variation of soil properties on a six-ha artificial catchment constructed near Cottbus, Germany, to investigate processes of initial ecosystem genesis. We wanted to see whether spatial auto-correlation patterns could be identified three years after site construction. Topsoil was sampled at 192 locations using a balanced nested design involving six spatial scales (0.2 m to >60 m) and analysed for particle size, organic matter content, pH, soluble P, and various fractions of selected metals. Variance components were estimated by residual maximum likelihood. The uncertainty of variance estimates was characterized by the Fisher Information matrix and likelihood joint confidence regions. The latter approach was used for the first time to characterize uncertainties of variance estimates in spatial nested sampling. Likelihood ratio tests showed that all variables were spatially auto-correlated, but the allocation of the variance to specific spatial scales was highly uncertain. For most variables, at least one variance component could not be estimated precisely because the profile likelihood was either flat or the maximum lay on the boundary of the parameter space. Uncertainty estimates derived from the Fisher Information either could not be computed or were unrealistic in these cases. Likelihood joint confidence regions gave more realistic uncertainty estimates. Joint confidence regions for accumulated variance components showed that the shape of the estimated variograms was poorly defined for most variables. Simulations indicated that poor identification of variance components might be a general problem of nested sampling surveys, which has been under-estimated in the past. Hence, our work provides some incentive for re-examining the statistical properties of the methodology.

Hintergrund: Bei frÜh- und termingeborenen Kindern tritt hÄufig in den ersten Lebenstagen bzw. -wochen nach der Geburt ein verminderter Abfluss von Augensekret via TrÄnengang auf. Dadurch kann sich ein Sekretstau entwickeln, der zu einer Infektion der Augen fÜhren kann. Eine Augeninfektion in der Neonatalphase wurde bis anhin mit Neosporin-Augentropfen® behandelt. Bei Kindern unter zwei Jahren besteht die MÖglichkeit einer erhÖhten Resorption und damit eines erhÖhten oto- und nephrotoxischen Potentials von Neomycinsulfat. Studienziel: Untersuchung des Einflusses der lokalen Applikation von Euphrasia-Augentropfen auf den Antibiotikaverbrauch bei Neugeborenen. Material und Methode: 24 frÜh- und termingeborene Kinder erhielten eine lokale Applikation von NaCl 0,9% plus Euphrasia-Augentropfen. 20 frÜh- und termingeborene Kinder der Kontrollgruppe wurden konventionell mit NaCl 0,9% behandelt. Ergebnisse: Bei einer Behandlung mit NaCl 0,9%, aber auch mit NaCl 0,9% plus Euphrasia-Augentropfen, konnte in den meisten FÄllen auf eine Antibiotika-Therapie verzichtet werden, vor allem bei positiven bakteriologischen Abstrichen mit Staphylococcus aureus. Eine Limitation dieses Pilotprojektes zeigt sich in den Strukturunterschieden sowohl der Neugeborenen wie auch der Augenabstrichresultate. In der Versuchsgruppe wiesen die Neugeborenen ein tieferes Geburtsgewicht und Gestationsalter auf und waren tendenziell klinisch instabiler. Schlussfolgerung: Bei einem positiven Augenabstrich ist eine Therapie mit einem Antibiotikum nicht in jedem Fall notwendig. Ein Kind sollte nicht immer primÄr mit antibiotikahaltigen Augentropfen behandelt werden.