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1.
The papers in this special issue of Human Nature collectively consider societal and individual responses to a wide variety of environmental and social risks. The first paper considers societal level effects of pathogen risk on collectivism and conformity, avoidance of outsiders, and in-group loyalty in a worldwide cross-cultural sample. The second deals with societal-level effects of resource unpredictability on the nature and conduct of warfare in eastern Africa. The third deals with effects of volcanic eruptions and earthquakes and mediating factors on individual perceptions of risk in Mexico and Ecuador. The final paper deals with effects of various types of father absence on women’s reproductive life histories in Bangladesh.  相似文献   

2.
Natural hazards such as floods, tsunamis, wildfire res, droughts, landslides, volcanic eruptions, windstorms, and earthquakes exist everywhere in the world. Earthquakes can pose the greatest threat to human lives, property, and economic development in our society. We review tools that have been developed to assist the earthquake risk management process. We also propose two mechanisms for earthquake risk management: one to possibly better predict earthquake damage magnitude (prediction markets), the other to prepare response team performance (recognition primed decision-making). In conjunction with broader use of information system technology, it may be possible to improve preparedness and response.  相似文献   

3.
聂文政  李明启 《应用生态学报》2021,32(10):3771-3780
强火山喷发是影响全球气候变化的重要因素。过去几十年,不同学者基于青藏高原地区树木年轮重建了多条气候变化序列,并依据这些序列研究了全球强火山喷发对青藏高原地区气候的影响。结果表明: 探讨强火山喷发对青藏高原气候影响的树轮序列主要分布在青藏高原东部。利用序列对比法和时序叠加法分析发现,中低纬度的强火山喷发对青藏高原地区温度和干湿变化影响显著,并在强火山喷发后的1~2年内出现降温或者发生干旱,而高纬度的强火山喷发影响较小。此外,连续的多次强火山喷发能导致该区出现年代际的冷期。影响强火山喷发气候效应的因素主要包括火山喷发位置、喷发强度、大气环流等。最后结合国内外研究现状,对未来需要开展的研究方向进行了展望。  相似文献   

4.
Deciphering ecological effects of major catastrophic events such as earthquakes, tsunamis, volcanic eruptions, storms and fires, requires rapid interdisciplinary efforts often hampered by a lack of pre-event data. Using results of intertidal surveys conducted shortly before and immediately after Chile's 2010 M(w) 8.8 earthquake along the entire rupture zone (ca. 34-38°S), we provide the first quantification of earthquake and tsunami effects on sandy beach ecosystems. Our study incorporated anthropogenic coastal development as a key design factor. Ecological responses of beach ecosystems were strongly affected by the magnitude of land-level change. Subsidence along the northern rupture segment combined with tsunami-associated disturbance and drowned beaches. In contrast, along the co-seismically uplifted southern rupture, beaches widened and flattened increasing habitat availability. Post-event changes in abundance and distribution of mobile intertidal invertebrates were not uniform, varying with land-level change, tsunami height and coastal development. On beaches where subsidence occurred, intertidal zones and their associated species disappeared. On some beaches, uplift of rocky sub-tidal substrate eliminated low intertidal sand beach habitat for ecologically important species. On others, unexpected interactions of uplift with man-made coastal armouring included restoration of upper and mid-intertidal habitat seaward of armouring followed by rapid colonization of mobile crustaceans typical of these zones formerly excluded by constraints imposed by the armouring structures. Responses of coastal ecosystems to major earthquakes appear to vary strongly with land-level change, the mobility of the biota and shore type. Our results show that interactions of extreme events with human-altered shorelines can produce surprising ecological outcomes, and suggest these complex responses to landscape alteration can leave lasting footprints in coastal ecosystems.  相似文献   

5.
Indonesia has recently been faced with a number of great problems: poverty, natural disasters such as tsunami, earthquakes, flooding and typhoons, volcanic eruptions, loss of biodiversity, decreasing water quality and quantity, increased pollution, and aesthetic degradation of the landscape. These disturbances have been caused by rapid changes in land use and land cover, deforestation, the application of monoculture farming systems in commercial agriculture, urbanization, industrialization, and other types of infrastructure development. The government, urban communities and companies have promoted some programs to ameliorate the problem of environmental degradation. The government has ratified law no. 26/2007 as a commitment to sustainability; this law ensures that cities are obliged to provide green open spaces covering a minimum of 30% of urbanized areas. Many metropolitan cities have feverishly enacted policies to promote greening programs, such as those applied in Jakarta. However, a new town—Sentul City—has engaged in policies that aim to create a well-designed eco-city with urban greenery and ecological networks. This new policy is supposed to herald a better future for urban quality. It is expected that green spaces will provide environmental services: water resource management, biodiversity conservation, carbon sequestration, and landscape beauty.  相似文献   

6.
We evaluated the radial growth response of adult Nothofagus pumilio (Poepp. et Endl) Krasser trees affected by tephra deposition following historical volcanic eruptions of the Puyehue–Cordón Caulle Volcanic Complex (PCCVC) in northern Patagonia. Standard tree–ring width chronologies were developed for trees from two sites that were affected by up to 55 cm of tephra during the 2011 eruption, which allowed us to detect the general tree–growth response to eruptions VEI ≥ 3 and VEI ≤ 2. The tree growth trend satisfactorily followed the mean temperature record (r = 0.42); however, the analysis of studentized residuals identified outliers (≥ ± 2 SD) directly related to the volcanic eruptions of the years 1921–1922 and 2011 and the respective post–eruption years, while for the 1960 eruption and following year, they largely exceeded the mean value of the residuals. The large amount of tephra deposited during the 1921–22 and 2011 eruptions caused physical damage to the tree canopy leading to the appearance of white rings and to locally absent rings. The rate of change in radial growth of trees during these eruptions presented significant declines in relation to the growth of five years before the eruption and to the following year. The low amount of tephra deposited during the 1960 eruption did not cause damage to the stands and trees increased their radial growth. In general, trees that had reduced radial growth experienced a remarkable recovery starting in the second or third post–eruption year. The amount of tephra deposited and the time of year of the volcanic eruptions had an important influence on tree rings. Some ecophysiological causes that could explain the growth responses of N. pumilio to tephra fall are discussed herein. Our study may provide useful insights to clarify the uncertain characteristics of some eruptions in the past or to detect the occurrence of large, undocumented volcanic eruptions throughout the Andes.  相似文献   

7.
Skin scrapings, mouth swabs, and faecal specimens from children with eruptions in the napkin area and from a series of normal infants were examined for the presence of Candida albicans.This was found in 41% of all napkin eruptions but in only one of the 68 normal infants. While C. albicans is a common secondary invader of all types of napkin eruption, primary Candida infection of the skin in the napkin area is probably uncommon.No evidence was found that generalized psoriasiform or eczematous eruptions occurring in association with napkin rashes are due to an allergic response to the fungus. C. albicans is more likely to be present in a napkin rash if the organism has been found in the alimentary tract.  相似文献   

8.
Forest productivity projections remain highly uncertain, notably because underpinning physiological controls are delicate to disentangle. Transient perturbation of global climate by large volcanic eruptions provides a unique opportunity to retrospectively isolate underlying processes. Here, we use a multi-proxy dataset of tree-ring records distributed over the Northern Hemisphere to investigate the effect of eruptions on tree growth and photosynthesis and evaluate CMIP6 models. Tree-ring isotope records denoted a widespread 2–4 years increase of photosynthesis following eruptions, likely as a result of diffuse light fertilization. We found evidence that enhanced photosynthesis transiently drove ring width, but the latter further exhibited a decadal anomaly that evidenced independent growth and photosynthesis responses. CMIP6 simulations reproduced overall tree growth decline but did not capture observed photosynthesis anomaly, its decoupling from tree growth or the climate sensitivities of either processes, highlighting key disconnects that deserve further attention to improve forest productivity projections under climate change.  相似文献   

9.
In recent years, it has become popular to attribute faunal change and mass extinction to impacts, volcanic eruptions, or climatic change. How well do these supposed causes compare to the excellent record of Cenozoic life, especially that of fossil mammals? Two different Cenozoic mammal diversity curves were compared, and important climatic, volcanic, and impact horizons were examined in detail. In no case is there a strong correlation between impacts, eruptions, or climatic events and any episode of mammalian turnover. On the contrary, most of the known impact, eruption, and climatic events of the Cenozoic occurred during intervals of faunal stability. Conversely, episodes of high turnover and faunal change among Cenozoic mammals correlate with no known extrinsic causes. Apparently, extrinsic environmental factors such as impacts, eruptions, and climate change have a minimal effect, and intrinsic biological factors must be more important.  相似文献   

10.
Volcanic eruptions impact the global and the hemispheric climate, but it is still unknown how and to what degree they force the climate system and in particular the global carbon cycle. In this paper, the relationships between individual eruptions (reconstructed for the past using written records), tree primary productivity (estimated using ring widths), photosynthetic rate and stomatal conductance (assessed by carbon and oxygen isotope data) are investigated, to understand the impact of volcanic eruptions on net primary production. Data from a mixed stand of Fagus sylvatica L. and Acer pseudoplatanus L. located in the area of the Vesuvio volcanic complex (Southern Italy) showed a significant decrease in ring width following each eruption. Isotope analyses indicate a change in climatic conditions after such events. Specifically, the lower oxygen isotope ratio in the tree‐ring cellulose strongly suggests an increase in relative humidity and a decrease in temperature, with the latter resulting in a strong limitation to tree‐ring growth. The carbon isotope ratio was only moderately but not significantly reduced in the years of volcanic eruption, suggesting no major changes in C fixation rates. This work is a case study on the effects of volcanic eruptions resulting in strong climatic changes on the local scale. This is an opportunity to explore the process and causal relationships between climatic changes and the response of the vegetation. Thus, we propose here a realistic model scenario, from which we can extrapolate to global scales and improve our interpretations of results of global studies.  相似文献   

11.
Paul Telner  J. E. Adam 《CMAJ》1965,93(8):358-363
Internal malignant tumours may stimulate the formation of tumour antigens which, by means of an antigen-antibody mechanism, can cause pruritus, ichthyosis, erythroderma, acanthosis nigricans, dermatomyositis, erythema-urticarial and vesiculo-bullous skin eruptions.Tumours may also interfere with normal immunity responses and allow various localized skin eruptions such as herpes zoster and epidermophytoses to escape their normal boundaries and become generalized.Skin malignancies may also be a sign of decreased immunoallergic response and by their presence alert the physician to search for an internal malignancy, either one associated with the skin lesion, such as a lymphoma, or an unrelated tumour.  相似文献   

12.
Here, we investigate Mid- to Late-Holocene vegetation changes in low-lying coastal areas in Tonga and how changing sea levels and recurrent volcanic eruptions have influenced vegetation dynamics on four islands of the Tongan archipelago (South Pacific). To investigate past vegetation and environmental change at Ngofe Marsh (‘Uta Vava’u), we examined palynomorphs (pollen and spores), charcoal (fire), and sediment characteristics (volcanic activity) from a 6.7-m-long sediment core. Radiocarbon dating indicated the sediments were deposited over the last 7700 years. We integrated the Ngofe Marsh data with similar previously published data from Avai’o’vuna Swamp on Pangaimotu Island, Lotofoa Swamp on Foa Island, and Finemui Swamp on Ha’afeva Island. Plant taxa were categorized as littoral, mangrove, rainforest, successional/ disturbance, and wetland groups, and linear models were used to examine relationships between vegetation, relative sea level change, and volcanic eruptions (tephra). We found that relative sea level change has impacted vegetation on three of the four islands investigated. Volcanic eruptions were not identified as a driver of vegetation change. Rainforest decline does not appear to be driven by sea level changes or volcanic eruptions. From all sites analyzed, vegetation at Finemui Swamp was most sensitive to changes in relative sea level. While vegetation on low-lying Pacific islands is sensitive to changing sea levels, island characteristics, such as area and elevation, are also likely to be important factors that mediate specific island responses to drivers of change.  相似文献   

13.
Espanto or susto has been analysed from various points of view in the last fifteen years. From a survey covering 109 case analyses collected in Nicolas Ruiz (Chiapas, Mexico), we reached the conclusion that this folk illness cannot be conceived of as a syndrome in the medical sense. A semiological analysis showed that espanto can be better described as an indigenous theory whose function is to relate illness events to other levels of reality.According to indigenous belief, the Holy Earth and the chtonian spirits of the underworld play an important role in the origin of the illness. This origin is associated with an opening of the earth as is illustrated in the earthquakes or the volcanic eruptions forming the prototype of a fright experience leading to espanto; or, it is attributed to agents who inhabit locations where the earth presents a fissure (river, ravine, cave). It is through these holes that the Holy Earth exerts her power. Concomitantly, the body of the victim is believed to open itself to the influences of the bad winds of espanto. Trembling is another aspect of the phenomenon which is observed at numerous levels: first, during the fright experience; second, when the victim falls ill (chills jumping in bed); and third, when the curandera takes the pulse of the patient to see if the blood is afraid. These multiple analogies lead to the assumption that there is a meaning shared by these separate manifestations.  相似文献   

14.
Volcanic eruptions modify environments physically and chemically with serious consequences for the biota. In this review, we analysed 80 papers reporting the effects of volcanic eruptions in freshwater environments and on freshwater organisms. An increase in water turbidity is the most common reported physical effect while increases in concentrations of inorganic elements, many representing nutrients for primary producers, are the most common chemical effects. Bacterial growth is usually stimulated, while autotrophs can be either positively or negatively affected depending on the type of impact. A persistent effect reported in the biota is changes to the assemblage, which could generate further changes in terms of ecosystem functions. This analysis also identifies some information gaps, particularly involving the effects of eruptions on heterotrophic biofilms in streams and on invertebrates and fish in lakes. Most studies were carried out soon after the volcanic eruption, so it is difficult to assess the recovery of the ecosystems. Eruptions present unique opportunities for scientific discovery, although such studies are often hindered by a lack of pre-eruption data, which would allow for a more comprehensive assessment of the effects.  相似文献   

15.
Hybrids of the cross Lycopersicon esculentum x L. chilense developedfrost-like eruptions on the lower, or less frequently, the uppersides of the leaf. The eruptions consisted of large undifferentiatedcells, usually free of chlorophyll. A continuously intergradingseries of cells occurred between normal and affected regions.The spots involved any or all tissue layers. Spotting was controlledby a single dominant gene from the L. chilense parent, oftendeficient in transmission. In addition, environment influencedincidence and severity of the condition. An unstable gene controllingdevelopment is hypothesized to mutate, producing substanceswith radiating effects.  相似文献   

16.
The paper presents results of a cross-sectional study regarding schoolchildren's seismic risk perception, awareness, and preparedness in a sample size of 817 in the state of Oaxaca, Mexico. The approach is the application of a questionnaire survey. The main conclusion is that schoolchildren considered in the study are vulnerable to earthquakes due to the lack of a seismic education program. Some relevant results are summarized as follows: (1) over 50% of schoolchildren reported “little fear,” about 25% reported “a lot of fear” during earthquakes, and 19.4% reported low levels of perceived coping abilities; (2) male children get less afraid and show an increased degree of belief in their ability to cope emotionally with earthquakes than females; (3) about 50% of schoolchildren showed deficiencies in knowledge about earthquakes; (4) older schoolchildren (fifth to sixth grade) are more knowledgeable on earthquakes than younger ones (third to fourth grade); (5) a significant number of schoolchildren are not well prepared for what to do before, during, and after an earthquake; and (6) in general, urban schoolchildren are better prepared toward earthquakes than semi-rural schoolchildren.  相似文献   

17.
Soon after the 1977–78 eruptions of the volcano Usu, there were created many gullies in which former topsoil, i.e., well-developed soil accumulated before the eruptions, was eroded in the crater basin, whereas the outside of the gully was covered with thick volcanic deposits. The short-dispersal-seed plants were the most abundant in the inside of gully where the former topsoil was exposed, however, they have not immigrated from external environments. The germination tests of the seeds extracted from the former topsoil demonstrated that viable seeds were buried at 1683.3/m2 for 9 years after the eruptions. At least, 12 herbaceous species, e.g.,Rumex obtusifolius, Geum macrophyllum var.sachalinense andPoa annua, were derived from the buried seeds in the former topsoil. Their contribution to revegetation was estimated to be 40.0% in the inside of gully where the former topsoil was exposed in 1983, suggesting that buried seeds are one of the most important seed source for revegetation even in the case of a volcano which produced pumice and ash by eruption.  相似文献   

18.
We review and compare well-studied examples of five large, infrequent disturbances (LIDs)—fire, hurricanes, tornadoes, volcanic eruptions, and floods—in terms of the physical processes involved, the damage patterns they create in forested landscapes, and the potential impacts of those patterns on subsequent forest development. Our examples include the 1988 Yellowstone fires, the 1938 New England hurricane, the 1985 Tionesta tornado, the 1980 eruption of Mount St. Helens, and the 1993 Mississippi floods. The resulting landscape patterns are strongly controlled by interactions between the specific disturbance, the abiotic environment (especially topography), and the composition and structure of the vegetation at the time of the disturbance. The very different natures of these interactions yield distinctive temporal and spatial patterns and demand that ecologists increase their knowledge of the physical characteristics of disturbance processes. Floods and fires can occur over a long period, whereas volcanic eruptions and wind-driven events often last for no more than a few hours or days. Tornadoes and floods produce linear patterns with sharp edges, but fires, volcanic eruptions, and hurricanes can affect broader areas, often with gradual transitions of disturbance intensity. In all cases, the evidence suggests that LIDs produce enduring legacies of physical and biological structure that influence ecosystem processes for decades or centuries. Received 14 July 1998; accepted 6 October 1998.  相似文献   

19.
A survey of springtails was conducted in 1984 on Volcano Usu which suffered damage to it's ecosystem from eruptions in 1977 and 1978. The summit area, almost completely deforested by the eruptions, was still inhabited by many forest species such asDesoria notabilis, Willowsia sp. 2,Pseudachorutes sp. 2,Isotoma sp. 4,Tullbergia yosii, Onychiurus sp. 1,Entomobrya sp. 2,Isotomiella minor, Proisotoma sp. 2,Xenylla sp.,Neanura frigida, etc. These species preferred standing or fallen dead trees, mosses, bark chips, former topsoils and soil around the root of plants. The fauna in the summit area was most similar to that of coniferous or broad-leaved forests surveyed on the foot of the mountain. This suggests that the 1977–78 eruptions did not exterminate these springtail species which probably survived on the standing trees or in the former topsoil.  相似文献   

20.
Recently, the involvement of Epstein-Barr virus (EBV) in hydroa vacciniforme (HV)-like eruptions has been suggested. To elucidate the role of EBV in this disease, we isolated EBV-infected cell clones from peripheral blood mononuclear cells (PBMC) and the skin lesions of a patient with HV-like eruptions; cells isolated from PBMC were designated SNK-12, and those from the eruption SNK-11. Both cells expressed CD16, CD56, and HLA-DR and had germline configurations of the T-cell receptor and the immunoglobulin genes, indicating that the cell clones were of NK cell lineage. The analysis of EBV terminal repeats indicated that the cells were monoclonal, had identical clonality, and originated from EBV-positive cells in the PBMC and eruption. Both clones expressed EBNA-1, but not EBNA-2. Although LMP-1 was weakly detected in SNK-11, no LMP-1 was detected in SNK-12. Interestingly, EBV-infected cells required less IL-2 for in vitro growth in the later phase of this disease and this appeared to correlate with the expression of LMP-1, suggesting that the proliferative capacity of the EBV-positive NK cells increased during the time course of the disease, and LMP-1 expression might be responsible for that. This is the first report of the isolation of EBV-infected cells from the skin lesions of HV-like eruptions and strongly suggests that the HV-like eruption in the patient was caused by clonal NK cells with latent EBV infection.  相似文献   

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