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1.
Natural disasters such as earthquakes have profound effects on the earth’s biodiversity. However, studies on immediate earthquake impacts are rarely conducted at fine scales due to logistical constraints. We conducted the first post-earthquake field survey in Wolong Nature Reserve, Wenchuan, China, less than 1 year after it was hit by a magnitude 8.0 earthquake in 2008. Since Wolong harbors approximately 10% of the endangered wild giant panda (Ailuropoda melanoleuca) population, the impact of the earthquake on the giant panda and its habitat is of particular concern. We established 15 transects in three focus areas within the Reserve where we classified occurrences of earthquake damage according to vegetation and geophysical characteristics. In the 11.2 km2 area sampled, we recorded 156 occurrences of earthquake damage consisting of landslides and mudflows, which comprised a total area of 0.88 km2. Of all earthquake damage occurrences sampled, only 36% of occurences (73% of surface area) corresponded to damaged areas previously detected through broad-scale remote sensing. The remaining damaged areas mainly consisted of occurrences too small to be detected without field observation. Although there were significant losses to tree and shrub species diversity and richness in earthquake-damaged areas, remnant vegetation was found in the majority (80%) of damaged areas, suggesting the potential for forest recovery. Most earthquake-damaged areas were too steep to be classified as suitable giant panda habitat (79%). In addition, a sizable number of signs of giant panda (67) and other wildlife (148) were observed near the earthquake-damaged areas, and there appeared to be avoidance of earthquake damage only at short-range distances. This study has implications for understanding the impact of natural disasters on biodiversity and highlights the importance of fine scale on-the-ground assessments of disaster impacts on wildlife and their habitats.  相似文献   

2.

Background

Earthquakes and other catastrophic events frequently occurring worldwide can be considered as outliers and cause a growing and urgent need to improve our understanding of the negative effects imposed by such disasters. Earthquakes can intensively impact the birth outcomes upon psychological and morphological development of the unborn children, albeit detailed characteristics remain obscure.

Methods and Findings

We utilized the birth records at Du Jiang Yan and Peng Zhou counties to investigate the birth outcomes as a consequence of a major earthquake occurred in Wenchuan, China on May 12, 2008. Totally 13,003 of neonates were recorded, with 6638 and 6365 for pre- and post- earthquake, respectively. Significant low birthweight, high ratio of low birthweight, and low Apgar scores of post-earthquake group were observed. In contrast, the sex ratio at birth, birth length and length of gestation did not show statistical differences. The overall ratio of birth-defect in the post-earthquake (1.18%) is statistically high than that of pre-earthquake (0.99%), especially for those in the first trimester on earthquake day (1.47%). The birth-defect spectrum was dramatically altered after earthquake, with the markedly increased occurrences of ear malformations. The ratio of preterm birth post-earthquake (7.41%) is significant increased than that of pre-earthquake (5.63%). For the birth outcomes of twins, significant differences of the ratio of twins, birth weight, ratio of low birthweight and birth-defect rate were observed after earthquake.

Conclusion

A hospital-based study of birth outcomes impacted by the Wenchuan earthquake shows that the earthquake was associated with significant effects on birth outcomes, indicating it is a major monitor for long-term pregnant outcomes.  相似文献   

3.
The Wenchuan earthquake (Richter scale 8) on 12 May 2008 in southwestern China caused widespread ecosystem damage in the Longmenshan area. It is important to evaluate natural vegetation recovery processes and provide basic information on ecological aspects of the recovering environment after the earthquake. To circumvent the weather limits of remote sensing in the Wenchuan earthquake-hit areas, and to meet the need for regional observation analyses, three Landsat TM images pre- and post-earthquake in Mao County were used for analysis. Post-earthquake normalized difference vegetation index (NDVI) values were compared to pre-earthquake values with an NDVI-based index differencing method to determine the extent to which the vegetation was damaged in relation to the pre-earthquake pattern, and the rate of recovery was evaluated. The spatial characteristics of vegetation loss and natural recovery patterns were analyzed in relation to elevation, slope and aspect. The results indicated that severely damaged sites occurred mainly in river valleys, within a range of 1,500?C2,500?m elevation and on slopes of 25?C55°. The distance from rivers, rather than the distance from active faults, controls the damage patterns. After 1?year of natural regeneration, 36?% of the destroyed areas showed a decrease in NDVI value, 28.8?% showed very little change, 19.1?% showed an increase, and 16.1?% also increased with a recovery rate greater than 100?%. Moreover, there is a good correlation between recovery rate and both slope and elevation, but recovery patterns in the damaged area are complicated. Our results indicate that natural recovery in this arid valley is a slow process.  相似文献   

4.
基于NDVI监测5.12震后岷江河谷映秀汶川段滑坡体植被恢复   总被引:1,自引:0,他引:1  
汶川5.12地震造成岷江流域生态环境严重受损,评估地震后自然植被恢复过程,对生态环境恢复和重建有着重要的意义。本研究以5.12地震前后(2007、2008及2011年)空间分辨率为30 m×30 m的TM遥感影像的NDVI指标为数据源,监测了岷江上游干旱河谷(映秀—汶川段)植被在地震前后的动态变化,并结合地形因子,分析了植被受损及地震3年后植被恢复的空间分布特征。结果表明:(1)地震造成的研究区滑坡体面积约5 413.95 hm2,占总面积的34.74%;(2)滑坡体发育总体上与海拔呈负相关,与坡度呈正相关,与坡向无显着相关;(3)地震3年后,受损植被的平均恢复率达66.71%,其中中等及良好恢复的面积为3 942.54 hm2,占滑坡总面积的72.82%。研究结果也显示植被恢复与坡度、海拔有很高的一致性,及植被恢复的复杂性。  相似文献   

5.
The question of whether large-scale disturbances, such as earthquakes, impact an animal’s behavior significantly is an important question, but one that is difficult to answer due to the unpredictability of these types of events. Here, we collected 323 GPS locations of four takin (Budorcas taxicolor tibetana) in 13 days before and after a powerful (8.0 magnitude) earthquake on May 12, 2008 in Sichuan Province, China. The movement during this period was compared to that of three of the same animals during a corresponding period in 2009 (April 30 to May 25) and a slightly later 2009 period based on the start of migration (May 6 to May 31). We found that home ranges reduced in size during each study period, due to the migration process, but with no discernable differences due to the earthquake. The takin also showed the same pattern of elevation change and linear travel distance during 2008 and 2009, indicating no detectable effect of the earthquake on spatial behavior of takin. These findings add to our knowledge of how animals respond to catastrophic natural events in the wild.  相似文献   

6.
Muscat Governorate in the Sultanate of Oman is located along the sea of Oman and urban development has therefore had to occur in the intervening flat coastal plains and valleys along the coastline. The physical location of Muscat Governorate exposes the city to heavy rain and cyclones as they hit the coastline from the Sea of Oman. This underlying exposure plays a major role in the risk processes that lead to the emphasis of particular climate change risks including storm surge and rain-related flooding as experienced during Gonu Cyclone in 2007 and Phet Cyclone in 2010. For assessing flooding risk analysis, this study combined flooding hazard maps with major land use cover to quantify and validate the risks of flash flooding to urban area and infrastructures. Analysis identified substantial areas within the governorate exposure to high, medium, and low risks from extreme rainfall events that could lead to direct damages to roads, buildings, and other properties. This reinforces the need to protect and strengthen current defenses against these events as well as greater preparedness in disaster response.  相似文献   

7.
卫星跟踪技术在鸟类迁徙研究中的应用及展望   总被引:11,自引:2,他引:9  
综述了利用人造卫星跟踪技术进行鸟类迁徙研究的现状和利用卫星遥感技术对鸟类栖息地环境进行分析研究的现状。指出了这两项技术目前存在的问题,提出将这两项技术结合起来将有助于弄清候鸟迁徙定向、迁徙路径选择的机理,揭开候鸟迁徙策略之谜,有助于从景观生态学和保护生物学的角度研究并预测环境变化给候鸟带来的影响。  相似文献   

8.
Integrating remote sensing and geographic information systems (GIS) technologies offers tremendous opportunities for farmers to more cost effectively manage the causes of crop stress. Initial soybean cyst nematode (SCN) population densities from 995 2-×-3-m quadrats were obtained from a soybean field near Ames, Iowa, in 2000. The percentage of sunlight reflected from each quadrat was measured weekly using a multispectral radiometer beginning in mid-May and continuing through mid-September. Aerial images were obtained at heights above the field ranging from 45 to 425 m on 12 dates during the soybean growing season. This was accomplished using color film and infrared film in conjunction with a filter to measure reflectance in the near-infrared region (810 nm). Satellite images (Landsat 7) were obtained for five dates during the 2000 growing season. Maps depicting initial SCN population densities, soybean yield, soy oil, and soy protein were generated using the GIS software program ArcView. Percentage reflectance (810 nm), aerial image intensity, and satellite image intensity data then were regressed against soybean yield, soy oil, and soy protein concentrations obtained from each geospatially referenced soybean quadrat. Percentage reflectance measurements explained up to 60% of the variation in initial SCN population densities within soybean quadrats and up to 91% of the variation in soybean yield. Aerial image and satellite image intensities explained up to 80% and 47% of the variation in soybean yield, respectively. Percentage reflectance data also explained 36% and 54% of the variation in oil and protein concentrations of the harvested soybeans, respectively. These results indicate that remote sensing coupled with GIS technologies may provide new tools to detect and quantify SCN population densities and their impacts on the quantity and quality of soybean yield.  相似文献   

9.
Earthquake‐generated tsunamis threaten coastal areas and low‐lying islands with sudden flooding. Although human hazards and infrastructure damage have been well documented for tsunamis in recent decades, the effects on wildlife communities rarely have been quantified. We describe a tsunami that hit the world's largest remaining tropical seabird rookery and estimate the effects of sudden flooding on 23 bird species nesting on Pacific islands more than 3,800 km from the epicenter. We used global positioning systems, tide gauge data, and satellite imagery to quantify characteristics of the Tōhoku earthquake‐generated tsunami (11 March 2011) and its inundation extent across four Hawaiian Islands. We estimated short‐term effects of sudden flooding to bird communities using spatially explicit data from Midway Atoll and Laysan Island, Hawai'i. We describe variation in species vulnerability based on breeding phenology, nesting habitat, and life history traits. The tsunami inundated 21%–100% of each island's area at Midway Atoll and Laysan Island. Procellariformes (albatrosses and petrels) chick and egg losses exceeded 258,500 at Midway Atoll while albatross chick losses at Laysan Island exceeded 21,400. The tsunami struck at night and during the peak of nesting for 14 colonial seabird species. Strongly philopatric Procellariformes were vulnerable to the tsunami. Nonmigratory, endemic, endangered Laysan Teal (Anas laysanensis) were sensitive to ecosystem effects such as habitat changes and carcass‐initiated epizootics of avian botulism, and its populations declined approximately 40% on both atolls post‐tsunami. Catastrophic flooding of Pacific islands occurs periodically not only from tsunamis, but also from storm surge and rainfall; with sea‐level rise, the frequency of sudden flooding events will likely increase. As invasive predators occupy habitat on higher elevation Hawaiian Islands and globally important avian populations are concentrated on low‐lying islands, additional conservation strategies may be warranted to increase resilience of island biodiversity encountering tsunamis and rising sea levels.  相似文献   

10.

Background

The aim of this study was to compare retrospectively the characteristics of chest injuries and frequencies of other, concurrent injuries in patients after earthquakes of different seismic intensity.

Methods

We compared the cause, type, and body location of chest injuries as well as the frequencies of other, concurrent injuries in patients admitted to our hospital after the Wenchuan and Lushan earthquakes in Sichuan, China. We explored possible relationships between seismic intensity and the causes and types of injuries, and we assessed the ability of the Injury Severity Score, New Injury Severity Score, and Chest Injury Index to predict respiratory failure in chest injury patients.

Results

The incidence of chest injuries was 9.9% in the stronger Wenchuan earthquake and 22.2% in the less intensive Lushan earthquake. The most frequent cause of chest injuries in both earthquakes was being accidentally struck. Injuries due to falls were less prevalent in the stronger Wenchuan earthquake, while injuries due to burial were more prevalent. The distribution of types of chest injury did not vary significantly between the two earthquakes, with rib fractures and pulmonary contusions the most frequent types. Spinal and head injuries concurrent with chest injuries were more prevalent in the less violent Lushan earthquake. All three trauma scoring systems showed poor ability to predict respiratory failure in patients with earthquake-related chest injuries.

Conclusions

Previous studies may have underestimated the incidence of chest injury in violent earthquakes. The distributions of types of chest injury did not differ between these two earthquakes of different seismic intensity. Earthquake severity and interval between rescue and treatment may influence the prevalence and types of injuries that co-occur with the chest injury. Trauma evaluation scores on their own are inadequate predictors of respiratory failure in patients with earthquake-related chest injuries.  相似文献   

11.
许学工  颜磊  许诺安 《生态学报》2008,28(12):5862-5870
自然遗产是人类的共同财富。在5.12汶川大地震的灾后重建过程中,不能忽视对自然遗产的保护和恢复。以都江堰市的灾后重建为例,探讨自然遗产的保护和恢复问题。首先,通过实地调查,了解都江堰市域的自然遗产受损状况,进行自然遗产地的地质灾害和生态脆弱性空间格局分析;在此基础上,针对自然遗产地的不同特点,提出了灾后重建的规划框架和可行措施。  相似文献   

12.
The DNA damage response (DDR) coordinates DNA repair with cell cycle checkpoints to ameliorate or mitigate the pathological effects of DNA damage. Automated quantitative analysis (AQUA) and Tissue Studio are commercial technologies that use digitized immunofluorescence microscopy images to quantify antigen expression in defined tissue compartments. Because DDR is commonly activated in cancer and may reflect genetic instability within the lesion, a method to quantify DDR in cancer offers potential diagnostic and/or prognostic value. In this study, both AQUA and Tissue Studio algorithms were used to quantify the DDR in radiation-damaged skin fibroblasts, melanoma cell lines, moles, and primary and metastatic melanomas. Digital image analysis results for three markers of DDR (γH2AX, P-ATM, P-Chk2) correlated with immunoblot data for irradiated fibroblasts, whereas only γH2AX and P-Chk2 correlated with immunoblot data in melanoma cell lines. Melanoma cell lines displayed substantial variation in γH2AX and P-Chk2 expression, and P-Chk2 expression was significantly correlated with radioresistance. Moles, primary melanomas, and melanoma metastases in brain, lung and liver displayed substantial variation in γH2AX expression, similar to that observed in melanoma cell lines. Automated digital analysis of immunofluorescent images stained for DDR biomarkers may be useful for predicting tumor response to radiation and chemotherapy.  相似文献   

13.
胡翔  白文科  董鑫 《生态学杂志》2020,39(3):969-978
基于地理信息系统和遥感数据处理软件平台,对四川省阿坝藏族羌族自治州九寨沟县在2017年8·8地震前后的生态环境质量进行了监测和分析。利用Landsat 8 OLI卫星传感器所获得的2016年(震前)和2017年(震后)的遥感影像数据,提取归一化植被指数、湿度分量、地表温度、归一化土壤指数分别作为绿度、湿度、热度、干度等4个指标,进行主成分分析得到遥感生态指数。根据该指数,可将九寨沟县生态环境质量状况分为优、良、中等、较差和差级。2016年九寨沟县有24.8%处于生态环境质量状况优,2017年震后则下降到19.84%,2017年生态环境质量状况较差和中等的面积占比呈增加趋势,分别占17.99%和33.93%;震中15.5 km缓冲区内生态环境质量状况优的面积占比下降最多,为5.01%;2017年8·8九寨沟地震对震中15.5 km缓冲区的生态环境质量状况有较明显的影响,县界内的三个自然保护区中九寨沟国家级自然保护区受到冲击最大。本研究可为九寨沟地区生态环境监测、灾害评价和恢复重建提供科学依据。  相似文献   

14.
15.
Pairs of guard cells form small pores called stoma in the epidermis, and the reversible swelling and shrinking of these guard cells regulate the stomatal apertures. The well-documented changes in guard cell volume have been associated with their vacuolar structures. To investigate the contribution of the guard cell vacuoles to stomatal movement, the dynamics of these vacuolar structures were recently monitored during stomatal movement in vacuolar-membrane visualized Arabidopsis plants. Calculation of the vacuolar volume and surface area after reconstruction of three-dimensional images revealed a decrease in the vacuolar volume but an increase in the vacuolar surface area upon stomatal closure. These results implied the possible acceleration of membrane trafficking to the vacuole upon stomatal closure and membrane recycling from the vacuole to the plasma membrane upon stomatal opening. To clarify and quantify membrane trafficking during stomatal movement, we describe in this addendum our development of an improved image processing system.Key words: stomata, guard cells, vacuole, membrane traffic, image processing  相似文献   

16.

Background

Research on long-term health effects of earthquakes is scarce, especially in low- and middle-income countries, which are disproportionately affected by disasters. To date, progress in this area has been hampered by the lack of tools to accurately measure these effects. Here, we explored whether long-term public health effects of earthquakes can be assessed using a combination of readily available data sources on public health and geographic distribution of seismic activity.

Methods

We used childhood stunting as a proxy for public health effects. Data on stunting were attained from Demographic and Health Surveys. Earthquake data were obtained from U.S. Geological Survey’s ShakeMaps, geographic information system-based maps that divide earthquake affected areas into different shaking intensity zones. We combined these two data sources to categorize the surveyed children into different earthquake exposure groups, based on how much their area of residence was affected by the earthquake. We assessed the feasibility of the approach using a real earthquake case – an 8.4 magnitude earthquake that hit southern Peru in 2001.

Results and conclusions

Our results indicate that the combination of health survey data and disaster data may offer a readily accessible and accurate method for determining the long-term public health consequences of a natural disaster. Our work allowed us to make pre- and post- earthquake comparisons of stunting, an important indicator of the well-being of a society, as well as comparisons between populations with different levels of exposure to the earthquake. Furthermore, the detailed GIS based data provided a precise and objective definition of earthquake exposure. Our approach should be considered in future public health and disaster research exploring the long-term effects of earthquakes and potentially other natural disasters.  相似文献   

17.
汶川大地震对生态系统的影响   总被引:24,自引:0,他引:24  
汶川大地震的主要影响区位于四川盆地西缘,是四川盆地向青藏高原的过渡地带,地质构造复杂,山高谷深坡陡,是我国生态环境十分脆弱的地区,同时该地区还是具有重要生态服务功能,是长江上游生态安全的重要屏障。汶川大地震不仅造成巨大人员伤亡和财产损失,也对生态系统造成了严重破坏,对区域生态安全带来巨大威胁。研究运用遥感数据和实地调查,评估了地震对生态系统的影响,研究结果表明:(1)汶川大地震造成严重的生态破坏,导致生态系统丧失面积为122136hm^2,并形成了包括汶川县、彭州市、绵竹市等10县市的地震生态破坏重灾区。(2)地震导致65,584hm^2大熊猫生境丧失,损失比例5.92%。(3)94.64%的受损生态系统分布在地震烈度Ⅸ以上区域,53.82%的受损生态系统分布在海拔2000m以下的区域,66.09%的受损生态系统分布在坡度30~50°之间。地震导致的生态破坏将影响区域生态安全,在恢复重建中要加强生态保护和生态系统的恢复重建。  相似文献   

18.
阿勒泰地区雪灾遥感监测模型与评价方法   总被引:5,自引:2,他引:5  
利用我国新疆阿勒泰地区1996~1997年两次雪灾期问的NOAA卫星数据及地面气象台站观测资料,建立了积雪深度遥感反演模型;利用线性混合光谱分解原理,研究了基于像元的积雪覆盖率及积雪空间分类算法;提出评价积雪对草地畜牧业危害程度的两种基于格网数据结构的定量化指数.结果表明,通过积雪深度反演模型和线性混合光谱分解方法可计算基于像元的积雪深度和覆盖率,提高积雪分类的精度.建立的基于格网单元的积雪危害指数模型可系统地表达积雪区的雪情、草情、畜情和气象因子的空间分布状况,综合反映积雪对草地畜牧业的危害程度。  相似文献   

19.
The twenty-first century is marked with exponentially increasing development of technologies that provide wireless communications. To the pollution of the atmosphere with radio and TV signals, not only satellite communications but also any varieties of the Wi-Fi networks are added. By 2010 in the USA, 285 million mobile phone subscribers have been registered (for a little bit more than 300 million inhabitants). The estimate for the world is more than 5 billion mobile phone users at approximately 7 billion people living on this planet. Approximately 2 years ago, the International Agency of Research on Cancer (IARC) classified the electromagnetic fields used in mobile communication as a possible cancerogene. This paper discusses the potential health hazard and lack of scientific assessment and regulatory actions in protection of the life on the planet.  相似文献   

20.
Abstract. Six stands located on different land forms in mixed old‐growth Nothofagus forests in the Matiri Valley (northwest of South Island, New Zealand) were sampled to examine the effects of two recent large earthquakes on tree establishment and tree‐ring growth, and how these varied across land forms. 50 trees were cored in each stand to determine age structure and the cores were cross‐dated to precisely date unusual periods of radial growth. The 1968 earthquake (M = 7.1, epicentre 35 km from the study area) had no discernible impact on the sampled stands. The impact of the 1929 earthquake (M = 7.7, epicentre 20 km from the study area) varied between stands, depending on whether or not they had been damaged by soil or rock movement. In all stands, the age structures showed a pulse of N. fusca establishment following the 1929 earthquake, with this species dominating establishment in large gaps created by landslides. Smaller gaps, created by branch or tree death, were closed by both N. fusca and N. menziesii. The long period of releases (1929–1945) indicates that direct earthquake damage was not the only cause of tree death, and that many trees died subsequently most likely of pathogen attack or a drought in the early 1930s. The impacts of the 1929 earthquake are compared to a storm in 1905 and a drought in 1974–1978 which also affected forests in the region. Our results confirm that earthquakes are an important factor driving forest dynamics in this tectonically active region, and that the diversity of earthquake impacts is a major source of heterogeneity in forest structure and regeneration.  相似文献   

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