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981.
Vulnerability assessment and adaptation to the impacts of sea level rise on the Kingdom of Bahrain 总被引:2,自引:0,他引:2
S. Al-Jeneid M. Bahnassy S. Nasr M. El Raey 《Mitigation and Adaptation Strategies for Global Change》2008,13(1):87-104
This paper assesses quantitatively the impact of sea level rise (SLR) at the global and regional scale as a result of climate
change (CC) on the coastal areas of the Kingdom of Bahrain’s islands (36 Islands). The standard Intergovernmental Panel on
Climate Change (IPCC) guidelines was modified as appropriate for the situation of the study area. Geographic Information Systems
(GIS) coupled with Remote Sensing (RS) were used as the main techniques of collecting, analyzing, modeling simulating and
disseminating information to build SLR scenarios in a geographically referenced context. Also, these tools were used to assess
vulnerability and risk of the coastal area of the islands with the expectation that coastal planner and government authorities
will profit from integrating these knowledge into a broad based environmental decision making. Three SLR scenarios: low, moderate
and high were developed to examine the impacts from SLR on all islands. The low SLR scenario (Optimistic) assumes a 0.5-m
rise above current sea level, the moderate scenario (Intermediate) assumes a one meter rise, and the high scenario (Pessimistic)
assumes a 1.5 m rise in sea level. Two more SLR scenarios were assumed to perform risk analysis, a 2 and 5 meter rise above
current sea level. The simulation of SLR are quite straightforward, emphasizing on the uses of both of the data that are incorporated
from the satellite images and the created Digital Elevation Model (DEM) to estimate SLR scenarios that are adapted in the
study. These data were used to predict consequences of the possibility of the rise in sea level at different scenarios which
may alter the landuse and patterns of human communities. Results indicate that low-lying coastal areas of Bahrain islands
are at risk from the effects of any SLR resulting from CC. These islands are vulnerable under different SLR Scenarios. More
than 17% of the country total area may be inundated under 1.5 m SLR in 2100. The total area that might be lost under different
sea level scenarios will vary from more than 77 km2 if SLR reaches 0.5 m, to about 100 km2 under 1.0 m SLR and may reach 124 km2 under 1.5 m SLR scenario. The total inundated areas due to risk scenarios will reach 133 km2, if the SLR rises to 2.0 m, and it is estimated to be more than (22%) of the main island total area. Under the second scenario,
if the SLR reaches 5.0 m, the main islands will lose approximately half of its area (47%) equal to 280 km2. Hawar islands group will lose about (30%) of its total area under 2.0 m SLR, which is about 15.5 km2.A SLR adaptation policy framework (APF) and adaptation policy initiatives (APIs) are suggested for planners to build upon
for reducing the likely effects of SLR in the Kingdom of Bahrain. The framework is composed of four steps namely, acquisition
of information, planning and design, implementation and monitoring and evaluation. A general policy framework for a national
response to SLR is suggested. Additionally, a range of policy adaptation options/initiatives to sustain coastal developments
under the likely effects of SLR are recommended. 相似文献
982.
Flower colour is an important signal used by flowering plants to attract pollinators. Many anthophilous insects have an innate colour preference that is displayed during their first foraging bouts and which could help them locate their first nectar reward. Nevertheless, learning capabilities allow insects to switch their colour preferences with experience and thus, to track variation in floral nectar availability. Manduca sexta, a crepuscular hawkmoth widely studied as a model system for sensory physiology and behaviour, visits mostly white, night-blooming flowers lacking UV reflectance throughout its range in the Americas. Nevertheless, the spectral sensitivity of the feeding behaviour of naïve moths shows a narrow peak around 450 nm wavelengths, suggesting an innate preference for the colour blue. Under more natural conditions (i.e. broader wavelength reflectance) than in previous studies, we used dual choice experiments with blue- and white-coloured feeders to investigate the innate preference of naïve moths and trained different groups to each colour to evaluate their learning capabilities. We confirmed the innate preference of M. sexta for blue and found that these moths were able to switch colour preferences after training experience. These results unequivocally demonstrate that M. sexta moths innately prefer blue when presented against white flower models and offer novel experimental evidence supporting the hypothesis that learning capabilities could be involved in their foraging preferences, including their widely observed attraction to white flowers in nature. 相似文献
983.
K. Satyanarayana M. Borah P. G. Rao 《Journal of Loss Prevention in the Process Industries》1991,4(5):344-347
Various models of fireball diameter have been evaluated by statistical techniques. The model of Gayle for fireball diameter estimation showed good agreement between the predicted and experimental data. The models relating to fireball duration, transmissivity and view factor have been selected based on their relative merits. A user interactive computer program has been developed to predict thermal hazards from fireballs in chemical process industries. 相似文献
984.
Although merit pay continues to receive much theoretical and practical attention, little systematic effort is devoted to determining how large a pay raise must be before employees see it as a pay raise. This study uses psychophysical reasoning and techniques in a sample of 192 student ‘employees’ to establish the size of pay raise thresholds in a relatively controlled setting. Results indicate that, below about the 7 per cent level, increases in pay amounts are unlikely to evoke positive perceptual and attitudinal reactions among employees. Theoretical, methodological, and practical implications of these results are highlighted. © 1997 by John Wiley & Sons, Ltd. 相似文献
985.
This article describes the integrated modeling approach for planning the size and the operation of constructed wetlands for
maximizing retention of nonpoint source pollutant loads and reservoir water-quality improvement at a catchment scale. The
experimental field-scale wetland systems (four sets, 0.88 ha each) have been in operation since 2002, where water depth was maintained
at 30–50 cm and hydraulic loading rate was at 6.3–18.8 cm/day. The wetland system was found to be adequate for treating polluted
stream water with stable removal e ciency even during the winter. The integrated modeling system (modified-BASINS) was applied to
the Seokmoon estuarine reservoir watershed and calibrated with monitoring data from constructed wetland, stream, and reservoir. The
calibrated integrated modeling system estimated that constructing wetlands on 0.5% (about 114 ha) of the watershed area at the mouth
of reservoir could reduce 11.61% and 13.49% of total external nitrogen and phosphorus loads, respectively. It also might improve the
nitrogen and phosphorus concentration of the reservoir by 9.69% and 16.48%, respectively. The study suggested that about 0.1%–1.0%
of the watershed area should be allocated for constructed wetland to meet specified water-quality standards for the estuarine reservoir
at the polder area where land use planning is relatively less complicated. 相似文献
986.
Distribution of Cu,Zn,Pb,Cr,Ni,Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determined.Nineteen sampling sites were distributed around the industrial zone on a surface area of about 100,000 m2.Atomic absorption spectroscopy and Alpha spectroscopy were used to quantify the heavy elements and polonium-210,respectively.Investigation on a particle scale was conducted by TEM and SEM coupled to EDX and X-ray cartography to determine the nature of heavy elements carriers and their distribution.Heavy elements were mainly concentrated inside the particle size fraction 50 μm.Their levels decreased with distance increasing from the industry.According to the reference soil,enrichment factors were about 10,15,32 and 100 times for Zn,Pb,Cu,and Cr,respectively inside the particle size fraction 50 μm on the closest sites to the industry.The main contaminant sources were transport and storage of row materials and the free release of phosphogypsum waste.Heavy elements were entrapped inside agglomerates of sulfates,phosphates and iron oxihydroxides in a di used shape.Polonium-210 with an enrichment factor of about 56,showed the same behavior of the spatial distribution of the trace elements. 相似文献
987.
This study explored whether two principles describe the relationship between the size of a pay increase (a bonus expressed as a percentage of current salary) and the attractiveness of that increase. Based on a sample of sales personnel (N = 639) and consistent with the constant proportion principle of the psychophysical law, pay increase attractiveness was unrelated to current salary level after controlling for the size of the percentage increase. In addition, at any given salary level, the relationship between the size of the increase and its attractiveness was curvilinear. The attractiveness of larger and larger bonus percentages continues to increase, but at a decreasing rate supporting the principle of diminishing returns. 相似文献
988.
Christina G.L. Nerstad Rosalind Searle Matej Černe Anders Dysvik Miha Škerlavaj Ronny Scherer 《组织行为杂志》2018,39(4):429-447
Interpersonal trust is associated with a range of adaptive outcomes, including knowledge sharing. However, to date, our knowledge of antecedents and consequences of employees feeling trusted by supervisors in organizations remains limited. On the basis of a multisource, multiwave field study among 956 employees from 5 Norwegian organizations, we examined the predictive roles of perceived mastery climate and employee felt trust for employees' knowledge sharing. Drawing on the achievement goal theory, we develop and test a model to demonstrate that when employees perceive a mastery climate, they are more likely to feel trusted by their supervisors at both the individual and group levels. Moreover, the relationship between employees' perceptions of a mastery climate and supervisor‐rated knowledge sharing is mediated by perceptions of being trusted by the supervisor. Theoretical contributions and practical implications of our findings are discussed. 相似文献
989.
990.
Shimabukuro VG Alexandre NM Coluci MZ Rosecrance JC Gallani MC 《International journal of occupational safety and ergonomics》2012,18(1):15-26
Physical therapists engage in work tasks that expose them to occupational risk factors related to musculoskeletal disorders. Due to the gap in the literature on instruments focused on those workers, this study adapted a job factors questionnaire to physical therapists, and assessed its psychometric properties. The questionnaire was adapted and its content validity was established. The psychometric properties were evaluated among 142 physical therapists. Reliability was verified using the temporal-stability design and internal consistency. Construct validity was assessed with the known-groups technique. Test-retest results demonstrated intraclass correlation coefficients between .82 and .90 (p < .001). Cronbach's α of .91 verified the reliability of the questionnaire. The known-groups technique demonstrated a statistically significant difference on the scores of the items when physical therapists were compared to office workers. The results indicated that the adapted questionnaire had acceptable psychometric properties for assessing problematic job factors among physical therapists working in hospitals. 相似文献