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1.
Comprehensive hazard mitigation involves (1) understanding natural systems, (2) assessment of interactions within and between social systems and the built environment, and (3) understanding geo-spatial processes. To achieve this, local emergency managers must recognize variability in vulnerable populations exposed to hazards and develop place-based emergency plans accordingly. In this study, we assess whether cities in Los Angeles County are subject to disproportionally greater earthquake losses modeled from a M7.8 earthquake on the San Andreas fault. Furthermore, we analyze whether the variation in demographic and socioeconomic characteristics across cities is associated with the earthquake losses. We were able to explain 23.2?% of variance in e conomic losses by looking at the percentage of minority residents, income, and renter residents in a city [ F(3,84)?=?8.47; p?<?.001]. Cities with primarily minority residents had greater economic losses when compared to cities with primarily White residents ( b?=?1.01; p?<?.001). When looking at the association between demographic predictors and potential casualty rate, the percentage of Hispanic residents was positively associated with the potential casualty rate. We argue that knowledge of the relationship between earthquake hazard and the demographic characteristics of people in the area at risk is essential to mitigate the local impact from earthquakes. In other words, we apply social vulnerability assessment as part of a comprehensive risk management framework to accelerate recovery after an event. Local policy makers and the private sector can use this approach to gain a better understanding of a city??s social vulnerability and adapt their preparedness efforts accordingly. 相似文献
2.
On April 20, 2010, the Deepwater Horizon oil rig exploded, and oil spilled from the breached well-head for months, leading to an unprecedented environmental disaster with implications for behavioral health. Disasters are thought to affect behavioral health, and social capital is thought to ameliorate behavioral health impacts after disasters, though empirical evidence is mixed. One possible explanation for the discrepancy in findings relates to the activation of social capital in different contexts. In a disaster context, certain types of social capital may be more beneficial than others, and these relationships could differ between those directly affected by the disaster and those who are unaffected. The goal of this study is to assess the relationships between different forms of social capital (community engagement, trust, and social support) on different behavioral health indicators (depression, anxiety, and alcohol misuse) using data from the first wave of the Survey of Trauma, Resilience, and Opportunity among Neighborhoods in the Gulf (STRONG), a probabilistic household telephone survey fielded 6 years after the onset of the Deepwater Horizon oil spill (DHOS). We employ a structural equation modeling approach where multiple social capital and behavioral health variables can be included and their pathways tested in the same model, comparing the results between those who reported experiencing disruptions related to the DHOS and those who did not. Among those who experienced the DHOS, social support was negatively associated with both depression (β?=???0.085; p?=?0.011) and anxiety (β?=???0.097; p?=?0.003), and among those who did not experience the DHOS, social support was positively associated with alcohol misuse (β?=?0.067; p?=?0.035). When controlling for the other social capital variables, social support was the only form of social capital with a significant relationship to behavioral health, and these relationships differ based on whether or not a person experienced the disaster. This suggests that social capital does not have a uniformly ameliorative relationship with behavioral health in the aftermath of disasters. 相似文献
3.
To assess possible impacts on Lake Pontchartrain fishes from the 2005 hurricanes, we compared trawl, beach seine, and gillnet collections taken before (2000–2003, 2005) and after (2006–2009) to determine if significant assemblage changes occurred. We also compared basic environmental variables to test for hurricane-related changes. Significant post-hurricane changes in fish assemblages occurred in trawl (analysis of similarity (ANOSIM), R?<?0.090, p?<?0.05) and beach seine (ANOSIM, R?<?0.120, p?<?0.05) collections across all seasons. Gillnet assemblages exhibited changes in only one season (ANOSIM, R?=?0.045, p?<?0.05). These consistently low global R values (all R?<?0.120) across all gears suggest only minor compositional changes in species. When peak abundance periods were compared for individual species, Gulf menhaden ( Brevoortia patronus) declined in trawl collections after the hurricanes (Friedman's test, χ 2?=?6.00, p?=?0.014) but increased in gillnet collections (Friedman's test, χ 2?=?5.00, p?=?0.025). Hardhead catfish ( Ariopsis felis) increased in trawl collections, but Gulf pipefish ( Syngnathus scovelli), naked gobies ( Gobiosoma bosc), and rough silverside ( Membras martinica) all declined in beach seine samples and Atlantic croakers ( Micropogonias undulatus), Spanish mackerel ( Scomberomorus maculatus), and sand seatrout ( Cynoscion arenarius) all declined in gillnet samples. In general, salinity increased and water clarity and dissolved oxygen decreased after the hurricanes. While the overall composition of Lake Pontchartrain fish assemblages remains stable, the significant decline of some species and changes in certain environmental variables are cause for concern. Future monitoring should determine if all elements of this estuary will recover from these impacts. 相似文献
4.
Monazite is a robust geochronometer and occurs in a wide range of rock types. Monazite also records shock deformation from meteorite impact but the effects of impact-related microstructures on the U–Th–Pb systematics remain poorly constrained. We have, therefore, analyzed shock-deformed monazite grains from the central uplift of the Vredefort impact structure, South Africa, and impact melt from the Araguainha impact structure, Brazil, using electron backscatter diffraction, electron microprobe elemental mapping, and secondary ion mass spectrometry (SIMS). Crystallographic orientation mapping of monazite grains from both impact structures reveals a similar combination of crystal-plastic deformation features, including shock twins, planar deformation bands and neoblasts. Shock twins were documented in up to four different orientations within individual monazite grains, occurring as compound and/or type one twins in (001), (100), \(\left( 10\bar{1} \right)\), \(~\{110\}\), \(\left\{ 212 \right\},\) and type two (irrational) twin planes with rational shear directions in \([0\bar{1}\bar{1}]\) and \([\bar{1}\bar{1}0]\). SIMS U–Th–Pb analyses of the plastically deformed parent domains reveal discordant age arrays, where discordance scales with increasing plastic strain. The correlation between discordance and strain is likely a result of the formation of fast diffusion pathways during the shock event. Neoblasts in granular monazite domains are strain-free, having grown during the impact events via consumption of strained parent grains. Neoblastic monazite from the Inlandsee leucogranofels at Vredefort records a 207Pb/ 206Pb age of 2010?±?15 Ma (2 σ, n?=?9), consistent with previous impact age estimates of 2020 Ma. Neoblastic monazite from Araguainha impact melt yield a Concordia age of 259?±?5 Ma (2 σ, n?=?7), which is consistent with previous impact age estimates of 255?±?3 Ma. Our results demonstrate that targeting discrete microstructural domains in shocked monazite, as identified through orientation mapping, for in situ U–Th–Pb analysis can date impact-related deformation. Monazite is, therefore, one of the few high-temperature geochronometers that can be used for accurate and precise dating of meteorite impacts. 相似文献
5.
We present measurements of hillslope debris flow impact pressures on small obstacles. Two impact sensors have been installed in a real-scale experimental site where 50?m 3 of water-saturated soil material are released from rest. Impact velocities vary between 2 and 13?m/s; flow heights between 0.3 and 1.0?m. The maximum impact pressures measured over 15 events represent between 2 and 50 times the equivalent static pressures. The measurements reveal that quadratic velocity-dependent formulas can be used to estimate impact pressures. Impact coefficients C are constant from front to tail and range between 0.4?<? C?<?0.8 according to the individual events. The pressure fluctuations to depend on the sensor size and are between 20% and 60% of the mean pressure values. Our results suggest that hazard guidelines for hillslope debris flows should be based on quadratic velocity-dependent formulas. 相似文献
6.
Extreme climatic events are likely to adversely affect many countries throughout the world, but the degrees among countries may be different. China and Japan are the countries with high incidences of extreme weather/disaster, both facing with the urgent task of addressing climate change. This study seeks to quantitatively compare the impacts of extreme climatic events on socioeconomic systems (defined as vulnerability) of the two countries by simulating the consequences of hypothetical same degree of electricity disruption along with extreme events. To do that, two computable general equilibrium models are constructed, by using which three-stage scenarios are simulated for China and Japan, respectively. The results reveal that China and Japan have unequal socioeconomic vulnerabilities to extreme events. (1) Negative impact of the same degree of power outages is bigger on China’s socioeconomic system than on that of Japan, and this difference is more obvious in the very short-run scenario. (2) The decline of China’s GDP, total output, and employment levels is 2–3 times higher than that of Japan, while the difference of the resident welfare levels is sharper, which of China drops 3–5 times of Japan. (3) Structural factors are the main reason for vulnerability differences between China and Japan, including the differences of expenditure structure, factor input structure for production of life requirement sectors, material and energy dependence for the production of industrial sectors, and usage structure of services outputs. Based on these findings, some policy implications and recommendations for fairness issues on climate change adaptation are proposed. 相似文献
7.
Flash flood disaster is a prominent issue threatening public safety and social development throughout the world, especially in mountainous regions. Rainfall threshold is a widely accepted alternative to hydrological forecasting for flash flood warning due to the short response time and limited observations of flash flood events. However, determination of rainfall threshold is still very complicated due to multiple impact factors, particular for antecedent soil moisture and rainfall patterns. In this study, hydrological simulation approach (i.e., China Flash Flood-Hydrological Modeling System: CNFF-HMS) was adopted to capture the flash flood processes. Multiple scenarios were further designed with consideration of antecedent soil moisture and rainfall temporal patterns to determine the possible assemble of rainfall thresholds by driving the CNFF-HMS. Moreover, their effects on rainfall thresholds were investigated. Three mountainous catchments (Zhong, Balisi and Yu villages) in southern China were selected for case study. Results showed that the model performance of CNFF-HMS was very satisfactory for flash flood simulations in all these catchments, especially for multimodal flood events. Specifically, the relative errors of runoff and peak flow were within?±?20%, the error of time to peak flow was within?±?2 h and the Nash–Sutcliffe efficiency was greater than 0.90 for over 90% of the flash flood events. The rainfall thresholds varied between 93 and 334 mm at Zhong village, between 77 and 246 mm at Balisi village and between 111 and 420 mm at Yu village. Both antecedent soil moistures and rainfall temporal pattern significantly affected the variations of rainfall threshold. Rainfall threshold decreased by 8–38 and 0–42% as soil saturation increased from 0.20 to 0.50 and from 0.20 to 0.80, respectively. The effect of rainfall threshold was the minimum for the decreasing hyetograph (advanced pattern) and the maximum for the increasing hyetograph (delayed pattern), while it was similar for the design hyetograph and triangular hyetograph (intermediate patterns). Moreover, rainfall thresholds with short time spans were more suitable for early flood warning, especially in small rural catchments with humid climatic characteristics. This study was expected to provide insights into flash flood disaster forecasting and early warning in mountainous regions, and scientific references for the implementation of flash flood disaster prevention in China. 相似文献
8.
Detailed estimates of economy-wide disaster losses provide important inputs for disaster risk management. The most common models used to estimate losses are input–output (IO) and computable general equilibrium (CGE) models. A key strength of these models is their ability to capture the ripple effects, whereby the impacts of a disaster are transmitted to regions and sectors that are not directly affected by the event. One important transmission channel is household migration. Changes in the spatial distribution of people are likely to have substantial impacts on local labour and housing markets. In this paper, we argue that IO and CGE models suffer from limitations in representing household migration under disaster risk. We suggest combining IO and CGE models with agent-based models to improve the representation of migration in disaster impact analysis. 相似文献
9.
The exploration of the characteristics of natural disasters (NDs) and their impacts have important implications for guiding disaster prevention and mitigation. This paper discussed the characteristics of the major NDs that occurred in mainland China between 1980 and 2011 based on the number of disasters and fatalities, the affected population, and the resulting economic damages. We further examined the relationships between the level of social/economic development and the disaster losses. At last, we also explored the trend variations in disaster losses and losses expressed as a percentage of gross domestic product (losses/GDP) for 31 provinces in China over the period from 1990 to 2011. The results show that over the past three decades, the number of major NDs and the number of affected population appear to exhibit a detectable increasing trend, while the direct economic losses and the deaths show a slight increase trend. The correlations between the number of disasters and the economic losses as well as deaths and between the economic losses and socioeconomic status were not significant ( p > 0.05), which indicates that the growth in the number of disasters do not result in a significant increase in the disaster losses. Further investigations demonstrate that as economies develop, there are fewer losses/GDP in China over the past two decades. The per capita accumulative losses and losses/GDP in the western and central regions were higher than that in the eastern parts of China. There are significant regional differences in the trends in disaster losses and losses/GDP in China. Statistics also indicate that more than 70 % provinces in underdeveloped regions show an increasing trend in disaster losses, whereas exceeding 90 % provinces exhibit a decreasing trend in their losses/GDP. These results suggest that the economic development may have played an important role in improving the capacity of disaster prevention and reduction. 相似文献
10.
Sixteen crater samples were analyzed by radiochemical neutron activation analysis for Ge, Ir, Ni, Os, Pd and Re. Two impact melt rock samples from Clearwater East (22 km) showed strong, uniform enrichments in all elements except Ge, corresponding to 7.4% C1 chondrite material. Interelement ratios suggest that the meteorite was a C1 (or C2) chondrite, not an iron, stony iron, or chondrite of another type. An Ivory Coast tektite (related to the 10 km Bosumtwi crater) was enriched in Ir + Os and Ni to about 0.04 and 1.6% of C1 chondrite levels, but in the absence of data on country rocks, the meteorite cannot yet be characterized.Impact melt rock samples from Clearwater West (32km), Manicouagan (70km), and Mistastin (28 km) showed no detectable meteoritic component. Upper limits, as Cl chondrite equivalent, were Os ≤ 2 × 10 ?3% (~0.01 ppb), Ni ≤ 2 × 10 ?1% (~20 ppm). Possible causes are high impact velocity and/or a chemically inconspicuous meteorite (achondrite, Ir,Os-poor iron or stony iron). However, a more likely reason is that some fraction of the impact melt remains meteorite-free, especially at craters with central peaks.Clearwater East is the first terrestrial impact crater found to be associated with a stony meteorite. Apparently the consistent absence of stony projectiles at small craters (< 1 km diameter) reflects their destruction in the atmosphere, as proposed by Öpik. 相似文献
11.
Small island developing states (or SIDS) are exposed to a large number of natural hazards and many characteristics of small
island developing states make them particularly vulnerable to the impacts of natural hazards. In spite of this acknowledged vulnerability, there are relatively few studies which focus
on the impacts of natural hazards in these countries. This paper presents a review of our current state of knowledge of impacts
in small island developing states and highlights a number of research needs. Central to these is the need to integrate natural
hazards research within a sustainable development context and the need to exploit existing procedures such as government coordinated
disaster impact assessments to generate a detailed understanding of natural hazards impacts. 相似文献
12.
A strong need exists to increase the knowledge and recognize the values of neighborhood services. This paper makes an attempt to examine the impact of neighborhood services on land values, through analysis based on results obtained from multi linear regression analysis. This case study was done in area of dense urban settlement to check the consequence of neighborhood services through the hedonic pricing model base variables which include the structural, locational, community and neighborhood services. The regression coefficient was checked at (p?<?0.05) level of significance for each variable. The primary data was collect through the questionnaire filling by random sampling and Punjab Urban Gazette was used for the verification of land values in study area. The results found a valuable potential on land and property values of neighborhood services through the regression analysis results express through R (0.926), R2 (0.856) and coefficient tables to represent the effect of each individual variable on property and land values. Every individual variable play role in defining the values of land and property based upon its utilization such as larger the structure of a property, more the covered area, larger size of a property more the land area higher price. Similarly, for locational factor study in geography, a piece of land adjacent to the road have high land values 50–70% compare to those located at distance. Very less attention has been paid on such issues in the world due to lack of effective urban planning and research on such crucial issues. If empirical studies on such issue has been done, effective way can be obtained for urban planning. 相似文献
13.
The Genç District is located on the Bingöl Seismic Gap (BSG) of the Eastern Anatolian Fault Zone (EAFZ) with its?~?34.000 residents. The Karl?ova Triple Junction, where the EAFZ, the North Anatolian Fault Zone, and the Varto Fault Zone meet, is only 80 km NE of the Genç District. To make an earthquake disaster damage prediction of the Genç District, carrying a high risk of disaster, we have (1) prepared a new geological map, and (2) conducted a single-station microtremor survey. We defined that three SW-NE trending active faults of the sinistral Genç Fault Zone are cutting through the District. We have obtained dominant period (T) as?<?0.2 s, the amplification factor (A) between 8 and 10, the average shear wave velocity for the first 30 m (Vs30) as?<?300 m/s, and the seismic vulnerability index (Kg) as?>?20, in the central part of the Genç District. We have also prepared damage prediction maps for three bedrock acceleration values (0.25, 0.50, 0.75 g). Our earthquake damage prediction scenarios evidenced that as the bedrock acceleration values increase, the area of soil plastic behavior expands linearly. Here we report that if the average expected peak ground acceleration value (0.55–0.625 g) is exceeded during an earthquake, significant damage would be inevitable for the central part of the Genç District where most of the schools, mosques, public buildings, and hospitals are settled-down. 相似文献
14.
Lead concentrations and isotopic composition of sediment samples collected from three sites within the Lebanese coastal zones were measured: at Akkar, Dora and Selaata. Akkar is located far from any direct source of contamination, while Dora and Selaata receive urban and industrial wastes, respectively. Low Pb concentrations (6–16 μg g −1) were detected in the Akkar sediments, and high concentrations of Pb (70–101 μg g −1) were detected in the Dora sediments. Measuring stable isotope ratios of Pb makes it possible to identify the principal sources of Pb in the Akkar sediments as Pb emitted from gasoline combustion and Pb originating from natural sources. On the other hand, Pb stable isotopic ratios in Dora sediments indicate that they are more highly influenced by anthropogenic sources. Isotopic Pb ratios in the Selaata deposits, where Pb concentrations range between 5 and 35 μg g −1, have an exceptional radiogenic signature for marine sediments 1.25 < 206Pb/ 207Pb < 1.6 and 0.5 < 206Pb/ 208Pb < 0.67, which shows the impact of the phosphogypsum discharged by Selaata’s chemical plant. Isotopic Pb analysis applied to EDTA extracts, to test the mobility of Pb, shows that that this mobility is high (>60%) after 24 h of extraction, and that the extracted Pb is less radiogenic than the residual Pb. 相似文献
15.
Residents of rural mountain settlements are constantly threatened by disasters such as landslides. Their risk perception directly or indirectly affects their behavioral choices. Introducing the concept of sense of place, this paper details its interactions with the risk perception of mountain hazards. Rural residents ( n = 348) in landslide-threatened areas of the Three Gorges Reservoir Area were questioned about their sense of place and risk perception. Partial least squares structural equation modeling was used to explore the interactions between various dimensions, and hypothetical tests were conducted. We found that dimensions of risk perception, such as Possibility and Unknown, had direct, negative impacts on the dimensions of sense of place, such as Society bond and Place dependence. Possibility had an indirect, yet more significant effect on Place attachment and Place identity, acting through Society bond. Rural residents often overestimate disaster risks due to fatalism, and a fear of the unknown stemming from low scientific literacy, which reduces their Place dependence. A complex interaction between sense of place and risk perception was observed. The findings provide a scientific basis for the government to formulate integrated policies regarding settlement relocation, disaster prevention and mitigation, and sustainable development. 相似文献
16.
Ambient air pollution, particularly in the urban environment of developing countries, has turned out to be a major health risk factor. We explore the compounded impact of age sensitivity, exposure, poverty, co-morbidity, etc., along with composite air pollution in determining morbidity and health burden of people in Lucknow, India. This cross-sectional study is confined to analyse respiratory health status across different socio-economic and geographic locations using n = 140 in-depth questionnaire method. We used mean daily ambient air pollution data of PM10, PM2.5, SO2, and NO2 for the 2008–2018 period. We used the ecological model framework to assess the risk at different hierarchical levels and compounded severity on a spatial scale. We also used Logistic regression model with log odds and odds ratio to analyze the association of risks outcomes with composite air pollution scores calculated using the principal component analysis method. There is a strong association of location-specific respiratory disease prevalence with an overall 32 percent prevalence. The prevalence of ecological model 1 (individual domain) is 4.3 percent, while ecological model 2 (community domain) has the highest prevalence at 32.4 percent. The logistic regression model shows that respiratory disease load is positively associated with age sensitivity (P < .001) and composite pollution level (P < .001). For another model with suffocation as the outcome variable, composite pollution level (P < .001) and exposure (P < .001) are positively associated. Optimum interventions are required at Ecological models 1, 2, and 3 levels for better respiratory health outcomes. 相似文献
17.
Assessment of social vulnerability has been recognized as a critical step to understand natural hazard risks and to enhance effective response capabilities. Although significant achievements have been made in social vulnerability researches, little is know about the comprehensive profile of regional social vulnerability in China. In this study, the social vulnerability to natural hazards was firstly divided into socioeconomic and built environmental vulnerability. Then, using factor analysis, we identified the dominant factors that influence the provincial social vulnerability in China to natural hazards based on the socioeconomic and built environmental variables in 2000 and 2010 and explored the spatial patterns of social vulnerability. The results indicated that the provincial social vulnerability in China showed significant regional differences. The social vulnerability in the southeastern and eastern regions of China was greater than its northern and central parts over the past decade. Economic status, rural (proportion of agricultural population and percentage of workers employed in primary industries), urbanization, and age structure (children) were the dominant driving forces of variations in provincial socioeconomic vulnerability in two studied years, while lifelines and housing age could explain most of changes in built environmental vulnerability in 2000 and 2010. There were no statistically significant correlations between social vulnerability and disaster losses ( p > 0.05), indicating the impact of disasters was also related to the intensity of hazards and exposure. Disaster relief funds allocated to each province of China depended more on its disaster severity than the regional integrated social vulnerability over the past decade. These findings would provide a scientific base for the policy making and implementation of disaster prevention and mitigation in China. 相似文献
18.
A total of twenty-three water samples were collected in winter 2013 to assess groundwater quality in the Oued Rmel aquifer in the Zaghouan governate in Tunisia. These samples were subject to in-field measurements of some physico-chemical parameters (temperature, pH, and salinity), and laboratory analysis of major elements. Several parameters were used to assess the quality of water destined for irrigation, including electrical conductivity (EC) and sodium adsorption ratio (SAR). As part of this work, GIS was used to study spatial distributions of SAR, EC, residual sodium carbonate, sodium percentage (%Na), Doneen’s permeability index, Kelly’s ratio, and magnesium hazard and, therefore, evaluated the water quality of Oued Rmel (good, fair, or poor) regarding irrigation. The major ions most abundantly found in the waters of Oued Rmel were in the following order: Na +?>?Ca 2+?>?Mg 2+?>?K + and Cl ??>?SO 42??>?HCO 3. 56% of water samples from the Oued Rmel aquifer showed a low alkalinization risk, where SAR was lower than 10, 39% have a medium soil destabilization risks (10?<?SAR?<?18), and just 5% indicated high alkalinity hazards (SAR?>?26). Samples of water intended for irrigation showed a medium to high sodicity and alkalinization risk. It is expected that output may help in assessing the impacts of water quality of the Oued Rmel aquifer used for irrigation. 相似文献
19.
In this article, disasters are understood as processes that have different impacts on social routines in terms of scale, scope
and duration. The extent of adaptive processes in society can provide the ground for a rough classification of disaster types.
Such classification has, on the one hand, practical and analytical advantages. On the other hand, they harbour the danger
of overlooking transitions of scale and discourage comprehensive scale-related learning forms. Based on the disaster scale
by Fischer (Int J Mass Emerg Disasters 1:91–107, 2003), flash floods in mountain rivers and torrents are described as extreme emergencies or small-town disasters. Three given
examples will clearly show that learning rarely takes place within an institutional setting that is subjected to small disasters, because the stakeholder’s focus remains on only one level. Therefore, we propose to implement a system of self-organised
and scale-independent learning, so called deutero learning, within the political subsystem. Following a damaging event, participative
processes that involve all levels should be initialised. Their task would be to assess the combination of causes and draw
conclusions for mitigation measures. An aggregation of these assessments would help the responsible political subsystems to
adapt the current natural disasters policy to the changing environmental conditions. 相似文献
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