2,389 research outputs found
A survey of birds of the Lower Gordon region, southwestern Tasmania
An area of southwestern Tasmania, the lower Gordon River, was surveyed for bird species during the summers of 1975/76, 1976/77 and 1977/78. Using a transect method of survey, 49 species were located; of these, six were considered very common, 12 common, 24 uncommon and seven rare.
No new species were discovered, but the known range of all species recorded was extended by the survey. The rare orange-bellied parrot was not located during the study. Bird species were correlated with vegetation structure based on the Specht classification. This classification, in retrospect, proved to be of only limited use but still showed broad habitat preference trends. The area surveyed appears to be typical of southwestern Tasmania but is unusual, if not unique, in that not one species of exotic bird was discovered in the study area, suggesting that the area is true wilderness
Fly-ash particles in lake sediments: extraction and characterisation. Report to the CEGB
Fly-ash particles are produced by high temperature combustion of coal and oil. They are
dispersed widely in the environment, despite the presence of electrostatic precipitators on
coal-fired station chimneys
The analysis of trace metals in surface waters from Scotland and Wales
188 water samples taken from Scottish and Welsh lakes in 1995/6 have been analysed for a range of
trace metals, Hg, As, Se, Be, V, Cr, Co, Ni, Cu, Zn, Mo, Ag, Cd, Sb, Ba, Tl, Pb, & Bi.
At all sites Hg, As, Se, Be, Bi, Pb and Ag were below limits of detection by the ICP-MS. The other
elements showed various geographical distributions. In Wales, the south-central region and Anglesey
appeared consistently higher and it is suggested that these are due to former mining and contemporary
smelting activities respectively. In Scotland, distributions were move diverse although southern and
south-west Scotland often appeared to show elevated levels as did sites on Orkney and Shetland. In
general, lake sites in the north-west and Hebrides showed lower concentrations.
Pnncipal Components Analysis (PCA) was used to try and determine any patterns in the data, but the
results were inconclusive. The PC axes explained little of the variability within the data and clusters of
sites on the bi-plots show little in common. However, only geographical location was available to be
used m the PCA interpretation and it may be that other factors (lake and catchment characteristics,
other water chemistry) would help explain the data more fully.
The data included in this report are from smgle water samples taken over a short period of time.
Therefore, althougl1 the data may show a useful 'snap-shot' of the situation, more information would be
available from analyses of the sediment record (to put the data into temporal context) and other
substrates where metal accumulation takes place. This would have the advantage of producing a time
averaged metal value, but more importantly would mean more values above analytical detection and
hence a better idea of metal distribution
A palaeoecological assessment of the acidification status of lakes in the north-west and west of Ireland
Acidification in the Cairngorms and Lochnagar: a palaeoecological assessment
Sensitive lakes in areas of the United Kingdom with moderate to high sulphur
deposition have been acidified since the middle of the nineteenth century- (Battarbee et al.
1988). Regions such as Galloway, south west Scotland (eg. Flower and Battarbee 1983,
Flower et al. 1987), Wales (eg. Battarbee et al. 1988, Fritz et aL 1990), Cumbria (eg.
Battarbee et al 1988, Atkinson and Haworth 1990), and Rannoch Moor in the central
Scottish Highlands (eg. Flower et al 1988) have been affected. This study extends the
geographical survey of lake acidification to the Caimgorm and Lochnagar regions of north
east Scotland (Figure 1). The Caimgorms and Lochnagar are areas of considerable
conservation value, forming the largest single area of land over 1000 m in the UK. The
Caimgorm mountain plateau is a National Nature Reserve, noted for its alpine flora and
fauna, whilst the Lochnagar range is a Scottish Wildlife Trust reserve.
A secondary- aim of the study was to evaluate the 11land-use 11 hypothesis (eg.
Rosenqvist 1977, 1978, 1981) as a mechanism for lake acidification by examining high
altitude sites with no active land-management. Sites selected are all remote, lie above the
tree line and have undisturbed catchments.
Lochnagar and the Caimgorms are situated on sensitive granite geology (Kinniburgh
and Edmunds 1986, Wells et al. 1986) in an area of moderate acid deposition (c. 0.95 g S
yr-1
). It can be predicted that sensitive lakes in this area (those having Ca2
+ values of <60
ÎŒeq i-1
) will have acidified (Battarbee 1989)
Accounting for Nanometer-Thick Adventitious Carbon Contamination in X-ray Absorption Spectra of Carbon-Based Materials
Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy is a powerful technique for characterizing the composition and bonding state of nanoscale materials and the top few nanometers of bulk and thin film specimens. When coupled with imaging methods like photoemission electron microscopy, it enables chemical imaging of materials with nanometer-scale lateral spatial resolution. However, analysis of NEXAFS spectra is often performed under the assumption of structural and compositional homogeneity within the nanometer-scale depth probed by this technique. This assumption can introduce large errors when analyzing the vast majority of solid surfaces due to the presence of complex surface and near-surface structures such as oxides and contamination layers. An analytical methodology is presented for removing the contribution of these nanoscale overlayers from NEXAFS spectra of two-layered systems to provide a corrected photoabsorption spectrum of the substrate. This method relies on the subtraction of the NEXAFS spectrum of the overlayer adsorbed on a reference surface from the spectrum of the two-layer system under investigation, where the thickness of the overlayer is independently determined by X-ray photoelectron spectroscopy (XPS). This approach is applied to NEXAFS data acquired for one of the most challenging cases: air-exposed hard carbon-based materials with adventitious carbon contamination from ambient exposure. The contribution of the adventitious carbon was removed from the as-acquired spectra of ultrananocrystalline diamond (UNCD) and hydrogenated amorphous carbon (a-C:H) to determine the intrinsic photoabsorption NEXAFS spectra of these materials. The method alters the calculated fraction of sp2-hybridized carbon from 5 to 20% and reveals that the adventitious contamination can be described as a layer containing carbon and oxygen ([O]/[C] = 0.11 ± 0.02) with a thickness of 0.6 ± 0.2 nm and a fraction of sp2-bonded carbon of 0.19 ± 0.03. This method can be generally applied to the characterization of surfaces and interfaces in several research fields and technological applications
Land-Use Experiments in the Loch Laidon Catchment
This report presents the results from the Stream Water Quality component
of the Loch Laidon catchment land-use experiment which commenced in
1992. The experiment was established with the aim of examining the effects
of cattle grazing on the aquatic and terrestrial habitats and biota of a
moorland area of upland Scotland
Mathematical stories: Why do more boys than girls choose to study mathematics at AS-level in England?
Copyright @ 2005 Taylor & FrancisIn this paper I address the question: How is it that people come to choose mathematics and in what ways is this process gendered? I draw on the findings of a qualitative research study involving interviews with 43 young people all studying mathematics in post-compulsory education in England. Working within a post-structuralist framework, I argue that gender is a project and one that is achieved in interaction with others. Through a detailed reading of Toni and Claudiaâs stories I explore the tensions for young women who are engaging in mathematics, something that is discursively inscribed as masculine, while (understandably) being invested in producing themselves as female. I conclude by arguing that seeing âdoing mathematicsâ as âdoing masculinityâ is a productive way of understanding why mathematics is so male dominated and by looking at the implications of this understanding for gender and mathematics reform work.This work is funded by the ESR
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