Preen gland removal increases plumage bacterial load but not that of feather-degrading bacteria

The preen gland is a holocrine sebaceous gland of the avian integument which produces an oily secretion that is spread on the plumage during preening. It has been suggested that birds may defend themselves against feather-degrading bacteria (FDB) and other potential pathogens using preen gland secretions. However, besides some in vitro studies, the in vivo bacterial inhibitory effects of the preen oil on the abundance of feather-associated bacterial species has not yet been studied in passerines. Here we tested the effect of gland removal on the abundance of FDB and other-cultivable bacterial loads (OCB) of male house sparrows (Passer domesticus). Our results did not support earlier results on in vitro antibacterial activity of preen oil against FDB since the absence of the preen gland did not significantly affect their loads related to the control birds. In contrast, we found that preen gland removal led to higher loads of OCB. This result suggests that the antimicrobial spectrum of the preen oil is broader than previously thought and that, by reducing the overall feather bacterial loads, the preen gland could help birds to protect themselves against a variety of potentially harmful bacteria.     

Effect of Changing VOC Influent Composition on the Microbial Community Structure of TBABs

Microbial communities in trickle bed air biofilters (TBABs) were evaluated under conditions of interchanging the feed volatile organic compounds (VOCs) and VOC mixtures. Three independent TBABs (Biofilter “A,” “B,” and “C”) were run under interchanging VOCs conditions with different initial VOCs. Two aromatic compounds (toluene and styrene) and two oxygenated compounds (methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK)) were interchanged as single solutes. Two other TBABs “D” and “E” were run for two VOC mixtures. Biofilter “D” had a VOC mixture with equal molar ratio of the four components and Biofilter “E” received a VOC mixture with its composition based on EPA 2003 emission report. Denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA genes was used to assess the microbial richness in TBABs for treating the VOC mixtures and the impact of interchanging VOCs on the bacterial community structure in the biofilters. The results from DGGE indicated that the microbial community structure in the biofilter was different after each interchange of VOCs. Some bands of microbial species faded and some bands were strengthened. For the two TBABs treating VOC mixtures, the microbial species did not show significant difference, but the richness among these species was different from each other.     

A Framework to Predict the Impacts of Shale Gas Infrastructures on the Forest Fragmentation of an Agroforest Region

We propose a framework to facilitate the evaluation of the impacts of shale gas infrastructures (well pads, roads, and pipelines) on land cover features, especially with regards to forest fragmentation. We used a geographic information system and realistic development scenarios largely inspired by the PA (United States) experience, but adapted to a region of QC (Canada) with an already fragmented forest cover and a high gas potential. The scenario with the greatest impact results from development limited by regulatory constraints only, with no access to private roads for connecting well pads to the public road network. The scenario with the lowest impact additionally integrates ecological constraints (deer yards, maple woodlots, and wetlands). Overall the differences between these two scenarios are relatively minor, with <1 % of the forest cover lost in each case. However, large areas of core forests would be lost in both scenarios and the number of forest patches would increase by 13–21 % due to fragmentation. The pipeline network would have a much greater footprint on the land cover than access roads. Using data acquired since the beginning of the shale gas industry, we show that it is possible, within a reasonable time frame, to produce a robust assessment of the impacts of shale gas extraction. The framework we propose could easily be applied to other contexts or jurisdictions.     

EU sustainable development indicators: An overview

The European Union's commitment to sustainable development at the 1992 Earth Summit resulted in an EU‐wide sustainable development strategy, adopted in Gothenburg in 2001. This article presents an overview of the set of sustainable development indicators (SDIs) recently adopted by the European Commission to monitor, assess and revise the strategy. It provides a critical assessment of the current status of the indicator set, and reviews the main policy trends in the areas of the strategy through a brief analysis of headline indicators, placing energy and climate change issues in a broader perspective. Finally, the article compares the energy SDIs to the recent inter‐agency energy indicators for sustainable development (EISD), underlining their similarities as well as their different priorities and objectives. The article concludes that further research is needed to improve the SDI set and further explore the linkages between themes.