Key factors affecting the diversity of Sphagnum cover inhabitants with the focus on ground beetle assemblages in Central-Eastern European peat bogs

Abstract A key structural component in peat bog formation is Sphagnum spp., which determines very specific associated environmental conditions. The aim of this study was to characterise some of the key factors affecting the diversity, species richness and abundance of sphagnum inhabiting ground beetles and to examine the maintenance of stable populations of cold adapted specialised peat bog species. A total of 52 carabid species were recorded by pitfall traps along six main habitats, such as the lagg zone, pine bog, hollows, hummock open bog and dome. The results are characterised by a low diversity, which vary significantly among habitat types, and include a high abundance of a few carabid species. Among the variables influencing carabid species richness and abundance were plant cover, pH and the conductivity of the Sphagnum mat water. Vascular plant cover was a key factor shaping carabid beetle assemblages in the slope and the dome, while electric conductivity affected carabid beetle assemblage in the lagg. Whereas, the water level was the most important factor for the hollows. At the same time, peat bog specialists showed low sensitivity to the gradient of the analysed variables. Most of the specialised species are protected boreal beetles in the temperate zone of Europe, and therefore Belarusian peat bogs are a significant repository of cold adapted specialised bog species and potentially represent a significant refugia for these species in the context of global warming

Electron trapping at point defects on hydroxylated silica surfaces

The origin of electron trapping and negative charging of hydroxylated silica surfaces is predicted based on accurate quantum-mechanical calculations. The calculated electron affinities of the two dominant neutral paramagnetic defects, the nonbridging oxygen center, equivalent to Si-O-center dot, and the silicon dangling bond, equivalent to Si-center dot, demonstrate that both defects are deep electron traps and can form the corresponding negatively charged defects. We predict the structure and optical absorption energies of these diamagnetic defects

Radiation Emission by Electrons Channeling in Bent Silicon Crystals

Results of numerical simulations of electron channeling and emission spectra are reported for straight and uniformly bent silicon crystal. The projectile trajectories are computed using the newly developed module [1] of the MBN Explorer package [2,3]. The electron channeling along Si(110) crystallographic planes is studied for the projectile energy 855 MeV.Comment: 9 pages, 7 figures; submitted to European Physical Journal D. arXiv admin note: text overlap with arXiv:1307.678