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411.
Stijn Dhondt Quynh Le Xuan Hieu Vu Van Luc Hens 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(3):363-376
Traffic is an essential part of modern society and mobility is part of its socio-economic setting. However, signs of counter
productivity arise as the current mobility patterns substantially affect our health, including the consequences from traffic
accidents, air pollution—which causes even more victims than traffic accidents—and traffic-noise. The use of private motorised
vehicles also contributes to sedentarism, climate change and psychological effects. This paper reviews these mobility related
health effects and applies them to the situation in Hai Phong, a Vietnamese port-city in fast development and facing growing
mobility patterns. In his Master Plan the city developed a view on its development together with the transportation infrastructure
up to 2020. Together with the fast changing mobility patterns, such as a modal change from bicycles to motorcycles and cars,
this lead to an increase in motorized vehicles and non-negligible environmental health risks. Applying the methodology of
a Health Impact Assessment as used in previous studies the current health burden is estimated, focussing on particulate matter
(PM) and noise. For PM10 1287 deaths per year were calculated for the current situation, where the estimated number of deaths by 2020 doubled up to
2741. Hospital admissions due to PM10 raised from 44,954 now to 51,467 in 2020 and for PM2.5 the restricted-activity days were calculated, accounting for 852,352 per year. For noise only calculations for the current
state (2007) were performed. The total estimated DALYs due to noise was 4758. 相似文献
412.
413.
The Islands of Réunion and Mayotte are French territories in the Indian Ocean and are prone to numerous and recurrent hazards
as well as to increasing vulnerabilities. This paper examines disaster risk reduction on non-sovereign islands through the
case studies of Réunion and Mayotte. The approach used is embedded in standard geographical approaches to risk analysis, focusing
on place-based vulnerability, in order to understand disaster risk and disaster risk reduction on both islands. In addition
to establishing baseline information and visiting both islands for further data, 21 semi-structured individual interviews
were completed to understand the people’s perceptions of the hazards and of their vulnerabilities. Disaster risk reduction
strategies, and attitudes from governing bodies implementing the strategies, tend to assume similar vulnerability contexts
as mainland France, despite obvious differences on the islands. Many policies are implemented in a top–down manner by those
from mainland France who have little interest in, and who do not fully take into consideration, local realities. This paper
contributes new case studies to the literature, especially in comparing two non-Anglophone non-sovereign islands, and reinforces
recommendations factoring in local contexts when addressing ‘vulnerability of a place’ to disasters. 相似文献
414.
Stratigraphy of the Triassic?Jurassic Boundary Successions of the Southern Margin of the Junggar Basin, Northwestern China 总被引:2,自引:1,他引:1
SHA Jingeng Vivi VAJDA PAN Yanhong Linda LARSSON YAO Xiaogang ZHANG Xiaolin WANG Yaqiong CHENG Xiansheng JIANG Baoyu DENG Shenghui CHEN Siwei PENG Bo 《《地质学报》英文版》2011,85(2):421-436
The Triassic?Jurassic (Tr?J) boundary marks a major extinction event, which (~200 Ma) resulted in global extinctions of fauna and flora both in the marine and terrestrial realms. There prevail great challenges in determining the exact location of the terrestrial Tr?J boundary, because of endemism of taxa and the scarcity of fossils in terrestrial settings leading to difficulties in linking marine and terrestrial sedimentary successions. Investigation based on palynology and bivalves has been carried out over a 1113 m thick section, which is subdivided into 132 beds, along the Haojiagou valley on the southern margin of the Junggar Basin of the northern Xinjiang, northwestern China. The terrestrial Lower Jurassic is conformably resting on the Upper Triassic strata. The Upper Triassic covers the Huangshanjie Formation overlaid by the Haojiagou Formation, while the Lower Jurassic comprises the Badaowan Formation followed by the Sangonghe Formation. Fifty six pollen and spore taxa and one algal taxon were identified from the sediments. Based on the key-species and abundance of spores and pollen, three zones were erected: the Late Triassic (Rhaetian) Aratrisporites?Alisporites Assemblage, the Early Jurassic (Hettangian) Perinopollenites?Pinuspollenites Assemblage, and the Sinemurian Perinopollenites?Cycadopites Assemblage. The Tr?J boundary is placed between bed 44 and 45 coincident with the boundary between the Haojiagou and Badaowan formations. Beds with Ferganoconcha (?), Unio?Ferganoconcha and Waagenoperna?Yananoconcha bivalve assemblages are recognized. The Ferganoconcha (?) bed is limited to the upper Haojiagou Formation, Unio?Ferganoconcha and Waagenoperna?Yananoconcha assemblages are present in the middle and upper members of the Badaowan Formation. The sedimentary succession is interpreted as terrestrial with two mainly lake deposit intervals within Haojiagou and Badaowan formations, yielding fresh water algae and bivalves. However, the presence of brackish water algae Tasmanites and the marine?littoral facies bivalve Waagenoperna from the Badaowan Formation indicate that the Junggar Basin was influenced by sea water caused by transgressions from the northern Tethys, during the Sinemurian. 相似文献
415.
Olivier Cuisinier Jean-Claude Auriol Tangi Le Borgne Dimitri Deneele 《Engineering Geology》2011,(3):187
Under a given compaction energy and procedure, it is known that maximum dry density of a soil is lowered due to lime addition. This modification of maximum dry density could alter the hydraulic conductivity of the soil. The main object of this study was to assess the impact of lime-stabilization on a silt soil microstructure and then on saturated hydraulic conductivity. An investigation at the microscopic level with mercury intrusion porosimetry showed that lime treatment induced the formation of a new small class, with a diameter lower than 3 × 103 Å in the compacted soil. This class is responsible for the difference in dry density between the treated and the untreated sample after compaction. It is shown that this small pores class was not altered by the compaction water content, the compaction procedure or the dry density. As in untreated soils, only the larger pores were modified by the compaction water content and the compaction procedure in the lime treated samples. The hydraulic conductivity appeared to be only related to the largest pores volume of the tested silt, regardless of lime treatment. Therefore, this study demonstrated that even if addition of lime resulted in a dramatic change of the maximum dry density of the tested silty soil, its effect on hydraulic conductivity is limited. 相似文献
416.
Alain Genty Christophe Le Potier Stéphane Gounand 《Geotechnical and Geological Engineering》2011,29(4):537-554
Numerical simulations of the transport of radionuclide from high-level radioactive waste stored in geological repositories
often do not take into account construction defects in the repository. The potential impact of drilling and excavation deviation
from the engineer planned design is a priori considered negligible. We conducted computations on repository geometries that
contain deviations from horizontal of a few degrees. The analysis of the results shows that the impact of deviation defects
varies from 9 to 16%. A perfect control of the galleries and waste repository cell orientations is then of concern for radioactive
waste repository construction, failing which numerical simulations must be conducted on the worst geometric configuration
or margin errors added. On the other hand, if the orientation control is precise enough, a modification of the repository
design including controlled deviations from the horizontal may be of interest. 相似文献
417.
改良黄土强度特性与工程处置试验研究 总被引:1,自引:0,他引:1
本文针对山西朔州典型黄土,利用素黄土与石灰粉煤灰、石灰水泥、水泥粉煤灰三种改良黄土,进行了击实特性、抗剪强度特性及崩解特性试验研究,提出了黄土改良的最佳方案,并采用该方案对山西某煤矿电梯井填方段进行了数值模拟分析,验证了石灰粉煤灰改良黄土工程应用的可行性。试验结果表明:粉煤灰与黄土形成致密的混合结构,石灰的掺入,激活了粉煤灰的活性,发生了一系列的水化反应,使改良黄土的强度大大提高,改良黄土在物理力学性质方面有明显改善。 相似文献
418.
419.
A study of arsenic,iron and other dissolved ion variations in the groundwater of Bishnupur District,Manipur, India 总被引:1,自引:1,他引:0
Jayalakshmi Devi Oinam AL. Ramanathan Anurag Linda Gurmeet Singh 《Environmental Earth Sciences》2011,62(6):1183-1195
The presence of arsenic (As) in groundwater and its effect on human health has become an issue of serious concern in recent
years. The present study assessed the groundwater quality of the Bishnupur District, Manipur, with respect to drinking water
standards. Higher concentrations of pH, iron and phosphate were observed at several locations. Phosphate and iron levels were
highest in the pre-monsoon, followed by monsoon and post-monsoon seasons. The arsenic concentrations were highest during post-monsoon
(1–200 μg L−1) as compared to pre-monsoon (1–108 μg L−1) and monsoon (2–99 μg L−1). Kwakta and Ngakhalawai show higher levels of arsenic concentration as compared to the prescribed World Health Organization
(WHO) and Bureau of Indian Standards (BIS) norms. Arsenic showed a strong positive correlation with phosphate and negative
correlation with sulphate, suggesting a partial influence of anthropogenic sources. The study suggests that the Bishnupur
area has an arsenic contamination problem, which is expected to increase in the near future. 相似文献
420.