The Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory is a second generation water Cherenkov detector designed to determine whether the currently observed solar neutrino deficit is a result of neutrino oscillations. The detector is unique in its use of D2O as a detection medium, permitting it to make a solar model-independent test of the neutrino oscillation hypothesis by comparison of the charged- and neutral-current interaction rates. In this paper the physical properties, construction, and preliminary operation of the Sudbury Neutrino Observatory are described. Data and predicted operating parameters are provided whenever possible.Comment: 58 pages, 12 figures, submitted to Nucl. Inst. Meth. Uses elsart and epsf style files. For additional information about SNO see http://www.sno.phy.queensu.ca . This version has some new reference

Changing management in Scottish birch woodlands: a potential threat to local invertebrate biodiversity

The silvicultural management of Scottish birch woodlands for timber production is replacing traditional low intensity management practices, such as domesticated livestock grazing. These new management practices involve thinning of existing woodlands to prescribed densities to maximize biomass and timber quality. Although presently infrequent, the wide scale adoption of this practice could affect invertebrate community diversity. The impact of these changes in management on Staphylinidae and Carabidae (Coleoptera) in 19 woodlands in Aberdeenshire, north-east Scotland was investigated. Grazing and logging practices were important determinants of beetle community structure. Woodland area had no effect on any measure of beetle community structure, although isolation did influence the abundance of one carabid species. Changes towards timber production forestry will influence the structure of invertebrate communities, although the scale at which this occurs will determine its effect

Alpha richness and niche breadth of a widespread group of aquatic insects in Nearctic and Neotropical streams

The increase in species richness from the poles to the equator is one of the most consistent biogeographical patterns of species distributions. Using a globally distributed group of stream insects–black flies (Diptera: Simuliidae)–we addressed two questions: (i) How does α-richness vary among streams of the New World? (ii) Does niche width, as measured by a proxy based on stream-habitat conditions, differ between the Nearctic and Neotropical regions? In our analyses of α-richness, we consider the potential effects of area, elevation, sample size and season. Examining 296 streams in 12 regional collections, we found that α-richness differed little among New World streams. Using stream variables to delineate a measure of niche breadth, we also found no difference in the mean niche breadth of species between North and South America. Our results are consistent with niche conservatism. In other words, as black flies expanded into the tropics, their mean niche breadth did not contract relative to that of their northern counterparts. © 2016 John Wiley & Sons Lt