Time filter

Source Type

Schafer K.,Karlsruhe Institute of Technology | Thomas W.,German Meteorological Service DWD | Peters A.,Helmholtz Center for Environmental Research | Ries L.,Federal Environmental Agency UBA | And 23 more authors.
Atmospheric Chemistry and Physics | Year: 2011

A series of major eruptions of the Eyjafjallajökull volcano in Iceland started on 14 April 2010 and continued until the end of May 2010. The volcanic emissions moved over nearly the whole of Europe and were observed first on 16 April 2010 in Southern Germany with different remote sensing systems from the ground and space. Enhanced PM10 and SO2 concentrations were detected on 17 April at mountain stations (Zugspitze/Schneefernerhaus and Schauinsland) as well as in Innsbruck by in situ measurement devices. On 19 April intensive vertical mixing and advection along with clear-sky conditions facilitated the entrainment of volcanic material down to the ground. The subsequent formation of a stably stratified lower atmosphere with limited mixing near the ground during the evening of 19 April led to an additional enhancement of near-surface particle concentrations. Consequently, on 19 April and 20 April exceedances of the daily threshold value for particulate matter (PM10) were reported at nearly all monitoring stations of the North Alpine foothills as well as at mountain and valley stations in the northern Alps. The chemical analyses of ambient PM10 at monitoring stations of the North Alpine foothills yielded elevated Titanium concentrations on 19/20 April which prove the presence of volcanic plume material. Following this result the PM10 threshold exceedances are also associated with the volcanic plume. The entrainment of the volcanic plume material mainly affected the concentrations of coarse particles (>1 μm)-interpreted as volcanic ash-and ultrafine particles (<100 nm), while the concentrations of accumulation mode aerosol (0.1-1 μm) were not changed significantly. With regard to the occurrence of ultrafine particles, it is concluded that their formation was triggered by high sulphuric acid concentrations which are necessarily generated by the photochemical processes in a plume rich in sulphur dioxide under high solar irradiance. It became evident that during the course of several days, the Eyjafjallajökull volcanic emissions influenced the near-surface atmosphere and thus the ambient air quality. Although the volcanic plume contributed to the overall exposure of the population of the northern Alpine region on two days, only minor effects on the exacerbation of respiratory and cardiovascular symptoms can be expected. © 2011 Author(s).

Boll S.,Agency for Population Ecology and Nature Conservancy | Tobler U.,University of Zurich | Geiger C.C.,University of Zurich | Hansbauer G.,Bavarian Environment Agency LFU | Schmidt B.R.,University of Zurich
Amphibia Reptilia | Year: 2012

In three Bavarian populations of Alytes obstetricans that were studied for the occurrence of Batrachochytrium dendrobatidis, the pathogen was detected. This is the first account of chytridiomycosis in Bavaria, Germany. Infected tadpoles had low infection loads mostly of 101 to 102 genome equivalents. Under high-density rearing conditions in the laboratory mortality rates were high after metamorphosis. Some individuals, however, showed no infection with Bd, while others survived metamorphosis in spite of low Bd loads. A new approach was chosen to get historical data on Bd occurrence in one of these populations: skeletochronological phalanx cross sections of 248 individuals that had been collected in the late 1980s were used to analyse the epidermis for chytrid sporangia. No sporangia were detected, thus we conclude that this population was not affected by Bd in the past. © Koninklijke Brill NV Leiden, 2012.

Deffner V.,Ludwig Maximilians University of Munich | Kuchenhoff H.,Ludwig Maximilians University of Munich | Maier V.,Ludwig Maximilians University of Munich | Pitz M.,Bavarian Environment Agency LFU | And 8 more authors.
Journal of Exposure Science and Environmental Epidemiology | Year: 2016

Personal exposure to air pollution is associated with time-and location-specific factors including indoor and outdoor air pollution, meteorology and time activities. Our investigation aims at the description and identification of factors determining personal exposure to particle number concentration (PNC) in everyday situations. Ten volunteers recorded their personal exposure to PNC and kept an activity diary in three different seasons besides stationary measurements of ambient air pollution and meteorology. Background exposure to PNC was modelled using the most predictive variables. In a second step, the effects of the activities were calculated adjusted for the background exposure. The average personal PNC level was highest in winter and was three times higher than the mean stationary PNC level while staying indoors and two times higher while staying outdoors. Personal indoor PNC levels were significantly increased during the use of candles, cooking and the occurrence of smell of food. High stationary outdoor PNC levels and low dew point temperatures were associated with increased personal outdoor PNC levels. Times spent in public transport were associated with lower personal PNC levels than other times spent in transportation. Personal PNC levels in everyday situations exhibited a large variability because of seasonal, microenvironment-specific and activity-specific influences. © 2016 Nature America, Inc. All rights reserved.

Knaf T.,University of Wurzburg | Schade M.,Bavarian Environment Agency LFU | Lemmer H.,Bavarian Environment Agency LFU | Benz R.,University of Wurzburg | Benz R.,Jacobs University Bremen
Environmental Microbiology | Year: 2013

Heavy metal salts containing aluminium or iron are used in wastewater treatment to control excessive growth of the Gram-positive bacterium Microthrix parvicella, frequently observed in wastewater plants suffering from bulking, foaming and scum. Microthrix parvicella belongs to the class Actinobacteria but not to mycolata, although its taxonomic position in this class is not identified. Investigations using the microspheres adhesion to cells method (MAC) suggested that M. parvicella is as strongly hydrophobic as the mycolic acid containing actinomycetes. The cell wall of M. parvicella was investigated for the presence of water-filled channels using the lipid bilayer assay. An ion-permeable channel called MppA with a conductance of 600pS in 1M KCl was identified in cell wall extracts and purified to homogeneity. The cation-selective channel showed no voltage-dependent closure at higher voltages. Interestingly, MPPA could be blocked by heavy metal ions. Binding of polyvalent cations such as iron and aluminium was studied in titration experiments and revealed stability constants for their binding to MppA up to 700M-1. The cell wall channel of M. parvicella contains a binding site for polyvalent cations which may play a crucial role for the effect of heavy metals salts on M. parvicella-dominated activated sludge. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

Beudert B.,Bavarian Forest National Park | Bassler C.,Bavarian Forest National Park | Thorn S.,Bavarian Forest National Park | Thorn S.,TU Munich | And 7 more authors.
Conservation Letters | Year: 2015

Increasing natural disturbances in conifer forests worldwide complicate political decisions about appropriate land management. In particular, allowing insects to kill trees without intervention has intensified public debate over the dual roles of strictly protected areas to sustain ecosystem services and to conserve biodiversity. Here we show that after large scale bark beetle Ips typographus infestation in spruce Picea abies forests in southeastern Germany, maximum nitrate concentrations in runoff used for drinking water increased significantly but only temporarily at the headwater scale. Moreover, this major criterion of water quality remained consistently far below the limit recommended by the World Health Organization. At the same time, biodiversity, including numbers of Red-listed species, increased for most taxa across a broad range of lineages. Our study provides strong support for a policy to allow natural disturbance-recovery processes to operate unimpeded in conifer-dominated mountain forests, especially within protected areas. © 2014 The Authors.

Discover hidden collaborations