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Wielenbach, Germany

Jekel M.,TU Berlin | Dott W.,RWTH Aachen | Bergmann A.,Water Center | Dunnbier U.,Berliner Wasserbetriebe | And 11 more authors.

An increasing number of organic micropollutants (OMP) is detected in anthropogenically influenced water cycles. Source control and effective natural and technical barriers are essential to maintain a high quality of drinking water resources under these circumstances. Based on the literature and our own research this study proposes a limited number of OMP that can serve as indicator substances for the major sources of OMP, such as wastewater treatment plants, agriculture and surface runoff. Furthermore functional indicators are proposed that allow assessment of the proper function of natural and technical barriers in the aquatic environment, namely conventional municipal wastewater treatment, advanced treatment (ozonation, activated carbon), bank filtration and soil aquifer treatment as well as self-purification in surface water. These indicator substances include the artificial sweetener acesulfame, the anti-inflammatory drug ibuprofen, the anticonvulsant carbamazepine, the corrosion inhibitor benzotriazole and the herbicide mecoprop among others. The chemical indicator substances are intended to support comparisons between watersheds and technical and natural processes independent of specific water cycles and to reduce efforts and costs of chemical analyses without losing essential information. © 2014 Elsevier Ltd. Source

Houk V.,Academy of Sciences of the Czech Republic | Konig C.,Bavarian Environmental Agency

A small Cyclotella species (Thalassiosiraceae) from a subalpine lake Schliersee (Bavaria, Germany) is described. The species has characteristic valve morphology different from this of the other similar taxa. It differs from them especially with the presence of radially arranged ghost structures in the valve central part and with the presence and low number of transversal trabeculae inside the alveolus-maximally 6 in 1 μm. The valve morphology and ultrastructure of this taxon is described and its new name, Cyclotella hinziae, is proposed. Its valve morphology is compared and discussed with this of other similar taxa. © Czech Phycological Society (2015). Source

Muller J.,Bavarian Forest National Park | Muller J.,TU Munich | Wolfl M.,Bavarian Environmental Agency | Wolfl S.,Luchsprojekt Bayern | And 3 more authors.
Biological Conservation

The Bohemian Forest harbours one of the largest lynx populations in Central Europe, which arose from animals reintroduced in two adjacent national parks. Despite an increasing number of population modelling approaches, the differences between potential and realised lynx distributions urgently need to be explored. We used lynx monitoring data from 2005 to 2010 from 530 municipalities in eastern Bavaria and spatial estimates of roe deer densities to test the predictions that the probability of lynx occurrence (confirmed or unconfirmed) increases with (1) decreasing distance to the national park area, (2) increasing forest cover, (3) increasing proportion of state-owned forests, (4) increasing roe deer density and (5) decreasing human activity. Using a flexible additive boosting model, we identified the distance to the national parks as the dominant factor, with positive effects on lynx probability only up to 70. km from the centre of the two national parks. Moreover, forest cover and roe deer density were correlated with increasing lynx occurrence. The probability of unconfirmed lynx occurrence increased with the proportion of state-owned forest within a municipality. The most probable mechanism behind the distance variable is illegal killing outside of the national parks. We concluded that despite the small size of protected areas in Central Europe, they still provide important source areas for this large predator. Moreover, the results supported conclusions of previous modelling approaches on the exchange among existing subpopulations in Central Europe, and indicated that lynx currently might not be able to colonise the next suitable areas. © 2014 Elsevier Ltd. Source

Magg N.,Bavarian Forest National Park | Muller J.,Bavarian Forest National Park | Heibl C.,TU Munich | Hacklander K.,University of Natural Resources and Life Sciences, Vienna | And 5 more authors.

A population of Eurasian lynx Lynx lynx was established by reintroductions in the Bohemian Forest Ecosystem in the 1970s and 1980s. The most recent information on the population status indicates that the distribution has stagnated since the late 1990s, for unknown reasons. We assessed the availability of suitable habitat along the Austrian–German–Czech border, and hypothesized that the Bohemian–Bavarian lynx population is not in equilibrium with habitat suitability. Based on global positioning system data from 10 radio-collared lynx, we used a maximum entropy approach to model suitable habitat. Variables reflecting anthropogenic influence contributed most to the model and were negatively associated with the occurrence of lynx. We evaluated the model prediction using independent records of lynx from monitoring in Bavaria, Germany. Using our habitat approach we estimated the area of potential habitat, based on a mean annual home range of 445 km2 for males and 122 km2 for females. Our results indicated there were 12,415 km2 of suitable habitat, distributed among 13 patches, for a potential population of c. 142 (93–160) resident lynx. We assessed connectivity via least-cost paths and found that all suitable patches could be reached by the lynx. A comparison with the current distribution of lynx, however, confirms that a significant proportion of suitable habitat is not occupied, which indicates that the distribution is limited by factors other than habitat, with illegal killing being the most likely cause. Our study provides crucial information for the development of a conservation strategy and regional planning for the Bohemian–Bavarian lynx population. Copyright © Fauna & Flora International 2015 Source

Bach M.,Justus Liebig University | Letzel M.,Bavarian Environmental Agency | Kaul U.,Bavarian Environmental Agency | Forstner S.,Bavarian Environmental Agency | And 4 more authors.
Water Research

A Water Framework Directive pilot project combines measured data and model approaches to calculate fluxes and mass balance of the pesticide bentazone in an 81 km section of the river Main (Germany). During the study period (six weeks in spring 2004) the observed bentazone inflow and outflow in the river section amounted to 52.8 and 53.1 kg, respectively; the maximum concentrations reached 220 and 290 ng l-1. Based on sampling of seven sewage treatment plants a specific loss of 0.87 g bentazone per farm was calculated. Extrapolation to the entire sub-basin results in 2.6 kg bentazone in total as point source contribution from farms. Diffuse input into the surface water network occurred after an intensive rainfall event on May 7th. Total bentazone load was simulated with the pesticide emission model DRIPS to be 23.2 kg. One third of this load was estimated to be degraded by photolysis before reaching the main waterway, the river Main. The ATV water quality model was applied to predict the concentration profile of bentazone in river Main between Schweinfurt and Würzburg with reasonable results. The difference between total measured and modeled fluxes amounted to 1.5 kg corresponding to 2% of the overall input. The combined approach of monitoring and modeling appears to be a valuable strategy to quantify the relevance of point and non-point sources and to focus effective mitigation measures to the most relevant origins within a river basin. © 2010 Elsevier Ltd. Source

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