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131.
Robert J. Allison 《地球表面变化过程与地形》1988,13(8):729-736
Rock material strength is an important component of many geomorphological studies. Current methods for determining this parameter result in sample destruction, preventing further analysis. A new non-destructive technique is described for indirectly determining material strength, by measuring Dynamic Young's Modulus. Tests have been conducted on Jurassic Portland Limestone and Upper Cretaceous Chalk to assess the apparatus. Young's Modulus is becoming an increasingly important rock material property. 相似文献
132.
Heather Dunning Bonnie Janzen Allison Williams Sylvia Abonyi Bonnie Jeffery J. E. Randall Bill Holden Ronald Labonte Nazeem Muhajarine Gerry Klein Tracey Carr 《GeoJournal》2006,65(4):393-407
While many community initiatives have attempted to assess the nature and determinants of their citizens’ quality of life (QOL),
these initiatives have produced little about whether the key determinants of life quality differ by gender. Using both quantitative
and qualitative data from a recent QOL research project in Saskatoon, Saskatchewan, Canada, this study explores whether factors
that predict poor QOL are similar for women and men. The study also examines whether the nature of these gender differences
varies across low, medium and high socio-economic status locales. Results showed that men and women were very similar in:
(1) their QOL ratings, (2) reports of deterioration in neighborhood QOL, and (3) rating particular aspects of their neighborhood.
Few gender differences were also found when analyzing data referring to place characteristics and social cohesion. Multivariate
analysis revealed further similarities: (1) being divorced/widowed was a significant predictor of poor QOL, and (2) a negative
view of community security issues was associated with deterioration in perceived neighborhood quality of life. For women,
however, other variables were important predictors of QOL: being middle aged, being single, and having a poor opinion of the
overall quality of their neighborhood. Qualitative analysis revealed that while men and women shared concern about general
areas such as safety and neighborhood supports, their perceptions of the details around these issues differed. The multi-method
results suggest that urban policy actions should include a gendered discussion of common QOL issues. 相似文献
133.
Anne Browning-Aiken Barbara Morehouse Allison Davis Margaret Wilder Robert Varady David Goodrich Rebecca Carter Denise Moreno Emily Dellinger McGovern 《Climatic change》2007,85(3-4):323-341
This paper reviews regional climate knowledge and vulnerability in the northern Mexico San Pedro River Basin, with a focus
on water quality, quantity, and management issues on the Mexican side of the border. A discussion based on the available literature
is supplemented by a survey assessing concerns about water and the quality and usability of climate and hydrologic information
available to water managers and communities. The surveys indicate that the central concern for urban residents is the lack
of reliable potable water due to frequent service breakdowns–with climate change and variability, specifically drought and
high temperatures, as contributing factors. Water managers desire appropriate meteorological and hydrologic information to
improve planning strategies, but access to this information remains limited. Considerable disagreement exists about who should
pay for previously free or low-cost water and wastewater treatment. Urban users have little incentive to conserve because
of the present flat, low rate and frustration with service. In rural areas, while a majority of ranchers recognize that variable
climate and water loss could increasingly jeopardize their lifestyle, they seldom use meteorological information in planning
or modify their water consumption. Climate vulnerability also includes potential for serious environmental health issues due
to the presence of heavy metals and organic contaminants in the San Pedro. 相似文献
134.
135.
Although climate change is highly prevalent in the media, people in Europe and the United States are often unsure about climate change terms, processes, and its personal consequences. In other words, climate change communication seems to be largely failing so far. Among other communication tools, maps are widely used for explanatory purposes by scientists and the media. Here two questions arise: first, whether high map complexity may be too intricate to be understood and discourage people from deciphering the map; and second, whether personal interest in climate change can be influenced by the phenomenon depicted or the map’s scale. In a survey conducted among 109 students in the USA, 63% of respondents preferred a simple map, but a substantial subset, 37%, asked for complexity to receive more information. Regional phenomena evoked more concern than far-off phenomena (concern level index difference of 0.93 on a 5-ranked Likert scale). The advantage of maps showing local areas could not be statistically confirmed. 相似文献
136.
Outcrops of young, sedimentary, argillaceous rocks with well developed fabric display rapid changes in their properties when subject to tropical weathering. The change in the materials is often accompanied by mass movement activity and the geomorphological consequence in terms of landforms is usually the development of badlands topography. Detailed field and laboratory studies have been undertaken on the Joe's River Formation, Barbados, and the Lichi Melange, Taiwan. Both are sedimentary mudrocks with well developed, scaly fabrics. Physical and geotechnical laboratory tests have been conducted on samples collected from type site locations to elucidate associations between material properties, earth surface processes and landform development. While the inherent physical properties show little or no difference in the transition from unweathered to highly weathered materials, by applying the critical state model, the mudrock geotechnical properties can be shown to change significantly. As weathering commences, material strength surprisingly increases. Only after a period of more extensive weathering do mechanical properties confirm increasingly incompetent materials. The initial strength increase appears to be due to weathering-induced modification of the fabric. The subsequent strength drop is a product of weathering-induced modification of both the fabric and the in situ, intact sediment. It is suggested that by applying the critical state model, a greater consideration can be gained of the geotechnical response of the sediments to weathering. 相似文献
137.
Siddhartha Mitra Joseph J. Lalicata Mead A. Allison Timothy M. Dellapenna 《Marine pollution bulletin》2009,58(6):851-857
To assess the extent to which Hurricanes Katrina and Rita affected polycyclic aromatic hydrocarbons (PAH) in the Gulf of Mexico (GOM), sediment cores were analyzed in late 2005 from: a shallow shelf, a deeper shelf, and a marsh station. Sediment geochronology, fabric, and geochemistry show that the 2005 storms deposited ∼10 cm of sediment to the surface of a core at 5-12A. Bulk carbon geochemistry and PAH isomers in this top layer suggest that the source of sediment to the top portion of core 5-12A was from a relatively more marine area. Particulate PAHs in the marsh core (04 M) appeared unaffected by the storms while sediments in the core from Station 5-1B (deeper shelf) were affected minimally (some possible storm-derived deposition). Substantial amounts of PAH-laden particles may have been displaced from the seabed in shallow areas of the water column in the GOM by these 2005 storms. 相似文献
138.
ABSTRACTMuch has changed since the first mapping of single-sex couples and families from the 2006 Australian census. An increasing willingness to allow their identification in the census has accompanied increasing public acceptance of same-sex couples culminating in significant support for legalising same-sex marriage in a 2017 national survey. Technological advances permit complex cross-tabulations of Australian census data and more detailed characterisations of same-sex couples. New geographies differentiate between male and female couples with children, showing same-sex couples are not just a feature of some inner-city areas, though these remain important, but also of suburban, regional and some rural areas. Drawing on the 2016 census, contemporary geographies of same-sex couples with and without children in Australia and changes over the past decade in Sydney are analysed at a time of increased interest in this demographic. 相似文献
139.
Sinéad J. Lyster Alexander C. Whittaker Peter A. Allison Daniel J. Lunt Alexander Farnsworth 《Basin Research》2020,32(6):1547-1573
Depositional stratigraphy represents the only physical archive of palaeo-sediment routing and this limits analysis of ancient source-to-sink systems in both space and time. Here, we use palaeo-digital elevation models (palaeoDEMs; based on high-resolution palaeogeographic reconstructions), HadCM3L general circulation model climate data and the BQART suspended sediment discharge model to demonstrate a predictive, forward approach to palaeo-sediment routing system analysis. To exemplify our approach, we use palaeoDEMs and HadCM3L data to predict the configurations, geometries and climates of large continental catchments in the Cenomanian and Turonian North American continent. Then, we use BQART to estimate suspended sediment discharges and catchment-averaged erosion rates and we map their spatial distributions. We validate our estimates with published geologic constraints from the Cenomanian Dunvegan Formation, Alberta, Canada, and the Turonian Ferron Sandstone, Utah, USA, and find that estimates are consistent or within a factor of two to three. We then evaluate the univariate and multivariate sensitivity of our estimates to a range of uncertainty margins on palaeogeographic and palaeoclimatic boundary conditions; large uncertainty margins (≤50%/±5°C) still recover estimates of suspended sediment discharge within an order of magnitude of published constraints. PalaeoDEMs are therefore suitable as a first-order investigative tool in palaeo-sediment routing system analysis and are particularly useful where stratigraphic records are incomplete. We highlight the potential of this approach to predict the global spatio-temporal response of suspended sediment discharges and catchment-averaged erosion rates to long-period tectonic and climatic forcing in the geologic past. 相似文献
140.
Summary Most studies of the impact of local campaigning on the geography of election results in single-member constituency electoral systems have been conducted in countries where the 'first-past-the-post' system is employed. Australia uses the 'alternative vote' (AV) system for elections to the federal and some state Lower Houses, with parties competing for both first- and lower-preference votes. This paper analyses the relationship between spending and success in the contests for both types of votes at the 1995 New South Wales State Legislative Assembly election, with significant findings: the more intense a party's campaign, ceteris paribus, the more first-preference votes it obtained and the more lower-preference votess when these were reallocated. The AV system was recommended for adoption in the UK by a government-commissioned report in 1998, and the paper draws some implications for the UK situation. 相似文献