By using the hailstone disaster data,the spatio-temporal distribution characteristics of hailstone in Shijiazhuang,the relationship between the hailstone disaster and the weather system,the hailstone path were analyze...By using the hailstone disaster data,the spatio-temporal distribution characteristics of hailstone in Shijiazhuang,the relationship between the hailstone disaster and the weather system,the hailstone path were analyzed.Moreover,the risk zoning of hailstone disaster in every county(city) of Shijiazhuang was done according to the occurrence frequency of hailstone.The results showed that the spatio-temporal distribution characteristics of hailstone in Shijiazhuang were obvious,and there were 3 main paths.The zones where the paths passed were also the high risk areas of hailstone occurrence.The research provided the scientific guidance for the adjustment of agricultural industrial structure and the defense of hailstone disaster.展开更多
A model of debris flow risk zoning is carried out with momentum analysis of debris flow. This model zones the debris flow inundation fan with density and velocity calculated by numerical simulation. The risk classific...A model of debris flow risk zoning is carried out with momentum analysis of debris flow. This model zones the debris flow inundation fan with density and velocity calculated by numerical simulation. The risk classification standard is determined according to the ultimate bearing capacities of different structures under impacting. And the ultimate bearing capacities are tested by impact failure experiment of destruction. Two structures typical in Chinese mountain towns, reinforced concrete frame construction and brickwork with concrete, are chosen in the experiment. The model makes debris flow risk zoning quantitative and the results comparable widely. The results differ much from that of other methods especially in the identification of medium and low risk zones.展开更多
The occurrence of debris flow is affected by many factors. Risk zoning of debris flow plays a vital role in the early-warning and prediction of abrupt geological hazards, and exploration of new method is needed in the...The occurrence of debris flow is affected by many factors. Risk zoning of debris flow plays a vital role in the early-warning and prediction of abrupt geological hazards, and exploration of new method is needed in the early-warning and prediction of geological hazards. The extension theory is a new method to solve contradiction matters. Based on extension theory, AHP and GIS, the risk zoning model of debris flow was established in this paper. The result of this research provides a new way in the risk zoning, early-warning and prediction of debris flow展开更多
Based on meteorological data including daily sunshine duration, temperature and precipitation from 97 meteorological stations in Hunan province during the period of 1981—2010, in combination with the field experiment...Based on meteorological data including daily sunshine duration, temperature and precipitation from 97 meteorological stations in Hunan province during the period of 1981—2010, in combination with the field experiment in different places at different sowing dates, the precise climatic risk zoning of double cropping super rice cultivation has been studied by using the spatial interpolation method and other Geographical Information System(GIS)technologies. Three key climatic factors were selected including chilling in May, high temperature heat damage during July to early August and low temperature damage in autumn in this study. Furthermore, based on the analysis of climatic conditions suitable for double cropping super rice cultivation and climatic disasters, 8-22 ℃ active accumulated temperature, sunshine duration from late March to October, climatic risk index of the low temperature in autumn, and climatic risk index of chilling in May were selected as key climatic factors to study the precise agro-meteorological regionalization of double cropping super rice in Hunan province. The results showed that: the high-yielding zones of double cropping super rice in Hunan were mainly located in Zhuzhou, Hengyang, Yongzhou and Chenzhou City, the moderate-yielding zones were primarily located in the east and north reaches of Dongting Lake,together with most of Changsha, Zhuzhou and Xiangtan City, and other regions in Hunan were not suitable for double cropping super rice. These findings can provide valuable information for the large-scale cultivation of double cropping super rice in Hunan province.展开更多
[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chi...[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary (1951 to 2005) and The Yearbook of Meteorological Disaster in Anhui Province (2006 to 2009), we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment.展开更多
Previous studies on typhoon disaster risk zoning in China have focused on individual provinces or small-scale areas and lack county-level results.In this study,typhoon disaster risk zoning is conducted for China’s co...Previous studies on typhoon disaster risk zoning in China have focused on individual provinces or small-scale areas and lack county-level results.In this study,typhoon disaster risk zoning is conducted for China’s coastal area,based on data at the county level.Using precipitation and wind data for China and typhoon disaster and social data at the county level for China’s coastal area from 2004 to 2013,first we analyze the characteristics of typhoon disasters in China’s coastal area and then develop an intensity index of factors causing typhoon disasters and a comprehensive social vulnerability index.Finally,by combining the two indices,we obtain a comprehensive risk index for typhoon disasters and conduct risk zoning.The results show that the maximum intensity areas are mainly the most coastal areas of both Zhejiang and Guangdong,and parts of Hainan Island,which is similar to the distribution of typhoon disasters.The maximum values of vulnerability in the northwest of Guangxi,parts of Fujian coastal areas and parts of the Shandong Peninsula.The comprehensive risk index generally decreases from coastal areas to inland areas.The high-risk areas are mainly distributed over Hainan Island,south-western Guangdong,most coastal Zhejiang,the coastal areas between Zhejiang and Fujian and parts of the Shandong Peninsula.展开更多
Taking the rainstorm flood disaster of Huaihe River basin as the research object,according to the principles of risk assessment for natural disasters,starting from the fatalness of inducing factors and the vulnerabili...Taking the rainstorm flood disaster of Huaihe River basin as the research object,according to the principles of risk assessment for natural disasters,starting from the fatalness of inducing factors and the vulnerability of hazard bearing body,the weight of each impact factor was calculated by using AHP. By using spatial analysis and statistical function of GIS,the integrated risk chart of rainstorm flood disaster in Huaihe River basin was obtained. The results showed that the high risk areas of rainstorm flood disaster in Huaihe River basin mainly distributed in the southern part of Henan,the central northern part of Anhui and eastern part of Jiangsu Province. Due to higher fatalness of inducing factors in southern Henan,there was high risk in the region. Central Anhui and east Jiangsu were not only high-fatalness zones but also high vulnerability zones of population and economy.展开更多
[Objective] The aim was to study the flood disaster risks in Anhui Province based on GIS. [Method] Taking country as basic unit, the 1∶ 250 000 basic geographic data in Anhui Province as basis, from the angle of floo...[Objective] The aim was to study the flood disaster risks in Anhui Province based on GIS. [Method] Taking country as basic unit, the 1∶ 250 000 basic geographic data in Anhui Province as basis, from the angle of flood disaster hazard and economic vulnerability, and by dint of the calculation of the weight of each impact factor with entropy-based fuzzy AHP method, flood risk assessment model was established to study the flood disaster risks zoning in Anhui Province. Using nearly 10 years of disaster information in Anhui Province, the flood risk zoning of Anhui Province was studied. And the risks evaluation results of flood disaster risks in Anhui Province in recent 10 years were checked. [Result] The regional difference of flood disaster in Anhui Province was large. The most serious area of flood disaster was in Lingquan in Fuyang and Lingbi in Huaibei. The risks degree degraded from south mountainous area in north Anhui Plain to the mountainous area of west Anhui Province, from Huaibei Plain to the hilly area of Jianghuai and mountainous area of south Anhui Province. The disaster situation in Anhui Province in recent 10 years suggested that the areas suffering from serious economic losses were in Lingbi, Guzheng and Huainan in the south part of Huaibei Plain. The places having serious agricultural crops damages were in Tangshan and Xiao County in Huaibei Plain. Besides, the Jingzhai area in the Dabieshan in west Anhui Province also had serious agricultural crops in Jinzhai. Other places had limited disaster-stricken impacts; the distribution of disaster-stricken population and impacted area of agricultural crops were basically consistent. Therefore, the risk evaluation of flood disaster of Anhui Province based on GIS was basically consistent with reality. [Conclusion] This GIS-based flood risk zoning method had good practicability.展开更多
In this paper, from the differences to evaluate and manage the seismic uncertainty we analyzed the imperfection of determinant method and the Poisson model of probabilistic method in seismic risk analysis. Through stu...In this paper, from the differences to evaluate and manage the seismic uncertainty we analyzed the imperfection of determinant method and the Poisson model of probabilistic method in seismic risk analysis. Through studying and summarizing the relation of earthquake occurrence time, intensity and place, we deemed that the time uncertainty of earthquake occurrence interacts with that of space. We expressed the interaction with the concept of upbound earthquake occurrence number and deduced the Binomial model. The Binomial model can be applied in reflecting uncertainty of time and space. Comparing the determinant method and the Poisson model of probabilistic method with the Binomial model, we have got the idea that determinant and the Poisson model are two limits of the Binomial model. When the temporal-spatial uncertainty is infinity or infinitesimal, the binomial model tends to a determinant method and a Poisson model respectively. We also gave an approach to show the implied probability of intensity in the Earthquake intensity Zoning Map in China made in 1977. We also estimated the maximums of the implied probability of five high intensity areas in the Northern China.展开更多
Based on data of agricultural drought situation and sown area of main crops in each county or district of the Sichuan Basin, the spatial distribution and probability of agricultural drought risk at different risk leve...Based on data of agricultural drought situation and sown area of main crops in each county or district of the Sichuan Basin, the spatial distribution and probability of agricultural drought risk at different risk levels were studied using normal information diffusion method, and the risk zoning was carried out. The results showed that normal information diffusion method could fit the distribution of agricultural drought risk in the Sichuan Basin. By comparison with the end of the 20^th century, agricultural drought risk in Meishan, Chongqing City and so on increased at the beginning of the 21^st century when x1≥ 10% or x1≥40%. Agricultural drought risk was low in the west of the Sichuan Basin, which was related to rich precipitation here, but it was high in Bazhong, Zhongjiang, Luxian and so forth. The risk zoning results can provide scientific references for disaster prevention and emergency management of government.展开更多
Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management a...Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area (about 50.81%) was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found.展开更多
The Da Hinggan Mountains is one of the most important forest areas in China, but forest fire there is also of high frequency. So it is completely necessary to map forest fire risk zones in order to effectively manage ...The Da Hinggan Mountains is one of the most important forest areas in China, but forest fire there is also of high frequency. So it is completely necessary to map forest fire risk zones in order to effectively manage and protect the forest resources. Two forest farms of Tuqiang Forest Bureau (53 degrees 34'-52 degrees 15'N,124 degrees 05'-122 degrees 18'E) were chosen as typical areas in this study. Remote sensing (RS) and Geographic Information System (GIS) play a vital role and can be used effectively to obtain and combine different forest-fire-causing factors for demarcating the forest fire risk zone map. Forest fire risk zones were described by assigning subjective weights to the classes of all the coverage layers according to their sensitivity to fire, using the ARC/INFO GIS software. Four classes of forest fire risk ranging from low to extremely high were generated automatically in ARC/INFO. The results showed that about 60.33% of the study area were predicted to be upper moderate risk zones, indicating that the forest fire management task in this area is super onerous. The RS and GIS-based forest fire risk model of the study area was found to be highly compatible with the actual fire-affected sites in 1987. Therefore the forest fire risk zone map can be used for guidance of forest fire management, and as basis for fire prevention strategies.展开更多
The wrack or the ship out of control will drift with flow.One of the most important factors that drive the ship is flow current which moves circularly in tidal area.The wrack from same place always drifts in different...The wrack or the ship out of control will drift with flow.One of the most important factors that drive the ship is flow current which moves circularly in tidal area.The wrack from same place always drifts in different ways if the start time is different.So,during the ship drifting period,the drift trace is also determined by both wave and wind forces.The drift direction is limited by water depth which must be deeper than ship draft. These marine structures that can not afford the hit of wrack or will destroy the wrack must be well considered when they are placed near harbor and waterway or other water area with ship running.The risk zone should be consulted according to tide and weather conditions to protect structures and ships in necessary.A method is presented here to simulate the risk zone by 2D numerical hydraulic model with tidal current,wave,wind and water depth considered.This model can be used to built early-warning and protect system for special marine structure.展开更多
Since 2001, there have occurred in succession the 2001 Kunlun Mountains M S8. 1earthquake,the 2008 Wenchuan M S8. 0 earthquake,the 2010 Yushu M S7. 1 earthquake and the 2012 Lushan M S7. 0 earthquake in the periphery ...Since 2001, there have occurred in succession the 2001 Kunlun Mountains M S8. 1earthquake,the 2008 Wenchuan M S8. 0 earthquake,the 2010 Yushu M S7. 1 earthquake and the 2012 Lushan M S7. 0 earthquake in the periphery of the Bayan Har block. By comparison of the characteristics of seismic strain release variations before and after the Kunlun Mountains M S8. 1 earthquake in the same time length in the geodynamical related regions,we found that the seismic strain release was obviously enhanced after the earthquake in the Longmenshan area,Batang area,and the NS-trending valleys at the west of the Hot Spring Basin. The Wenchuan earthquake occurred in the first area,and the Yushu earthquake is related to the second area. After the earthquake rupture occurred on the East Kunlun fault zone on the northern boundary of the Bayan Har Block,crustal materials on the south side of the fault zone migrated to the southeast,leading to a concentration of tectonic deformation in the Longmenshan thrust belt, e ventually rupturing on the Longmenshan thrust belt. This earthquake case illustrates that seismicity enhancement zones are possibly prone to long-term destructive earthquakes. After the M S7. 3 earthquake in Yutian,Xinjiang on February 12,2014,earthquake frequency and seismic strain release markedly increased in the junction area between the eastern Qilian Mountain tectonic belt and the Altun Tagh fault zone,where more attention should be paid to the long-term seismic risk.展开更多
Considerable economic losses and ecological damage can be caused by forest fi res,and compared to suppression,prevention is a much smarter strategy.Accordingly,this study focuses on developing a novel framework to ass...Considerable economic losses and ecological damage can be caused by forest fi res,and compared to suppression,prevention is a much smarter strategy.Accordingly,this study focuses on developing a novel framework to assess forest fi re risks and policy decisions on forest fi re management in China.This framework integrated deep learning algorithms,geographic information,and multisource data.Compared to conventional approaches,our framework featured timesaving,easy implementation,and importantly,the use of deep learning that vividly integrates various factors from the environment and human activities.Information on 96,594 forest fi re points from 2001 to 2019 was collected on Moderate Resolution Imaging Spectroradiometer(MODIS)fi re hotspots from 2001 to 2019 from NASA’s Fire Information Resource Management System.The information was classifi ed into factors such as topography,climate,vegetation,and society.The prediction of forest fi re risk was generated using a fully connected network model,and spatial autocorrelation used to analyze the spatial aggregation correlation of active fi re hotspots in the whole area of China.The results show that high accuracy prediction of fi re risks was achieved(accuracy 87.4%,positive predictive value 87.1%,sensitivity 88.9%,area under curve(AUC)94.1%).Based on this,it was found that Chinese forest fi re risk shows signifi cant autocorrelation and agglomeration both in seasons and regions.For example,forest fi re risk usually raises dramatically in spring and winter,and decreases in autumn and summer.Compared to the national average,Yunnan Province,Guangdong Province,and the Greater Hinggan Mountains region of Heilongjiang Province have higher fi re risks.In contrast,a large region in central China has been recognized as having a long-term,low risk of forest fi res.All forest risks in each region were recorded into the database and could contribute to the forest fi re prevention.The successful assessment of forest fi re risks in this study provides a comprehensive knowledge of fi re risks in China over the last 20 years.Deep learning showed its advantage in integrating multiple factors in predicting forest fi re risks.This technical framework is expected to be a feasible evaluation tool for the occurrence of forest fi res in China.展开更多
The homogeneous risk characteristics within a sub-area and the heterogeneous from one sub-area to another are unclear using existing environmental risk zoning methods. This study presents a new zoning method by determ...The homogeneous risk characteristics within a sub-area and the heterogeneous from one sub-area to another are unclear using existing environmental risk zoning methods. This study presents a new zoning method by determining and categorizing the risk characteristics using the k-means clustering data mining technology. The study constructs indices and develops index quantification models for environmental risk zoning by analyzing the mechanism of environmental risk occurrence. We calculate the source risk index, air risk field index, water risk field index, and target vulnerability of the study area with Nanjing Chemical Industrial Park using a 100 m - 100 m mesh grid as the basic zoning unit, and then use k-means clustering to analyze the environmental risk in the area. We obtain the optimal clustering number with the largest average silhouette coefficient by calculating the average silhouette coefficients of clustering at different k-values. The clustering result with the optimal clustering number is then used for the environmental risk zoning, and the zoning result is mapped using the geographic information system. The study area is divided into five sub-areas. The common environmental risk characteristics within the same sub-area, as well as the differences between sub- areas, are presented. The zoning is helpful in risk management and is convenient for decision makers to distribute limited resources to different sub-areas in the design of risk reducing intervention.展开更多
Geohazards are a recurrent issue in the Kerio River catchment of Kenya, which usually results in life and property loss. This research focuses on mapping geo-hazard risk zones of the region. The risk zones were develo...Geohazards are a recurrent issue in the Kerio River catchment of Kenya, which usually results in life and property loss. This research focuses on mapping geo-hazard risk zones of the region. The risk zones were developed from a combination of land use land cover maps, agroecological zones maps and soil erosion maps using the Analytical Hierarchy Process method of multi-criteria analysis. The final results depict the geohazard risk maps which show the susceptibility of different areas in the catchment (classified as risk zones) to hazards. The zones range from no risk zones to very high-risk zones. The results showed that the lowlands are most susceptible to hazards as they were classified as high-risk zones. These risk zone areas have impacts on the socio-economic development hence negatively impacting livelihoods in the area.展开更多
Using the latest results of seismic tomography, we studied the deep tectonic settings of the moderate and strong earthquakes in Anhul Province and its neighboring areas (28° - 39°N, 112°- 124°E)....Using the latest results of seismic tomography, we studied the deep tectonic settings of the moderate and strong earthquakes in Anhul Province and its neighboring areas (28° - 39°N, 112°- 124°E). The results are as follows: (1) There exists a certain correlation between the location of moderate-strong earthquake, the geologic structure of the surface and the partitioning of active tectonic elements with the upper-crust velocity structure. Most earthquakes recording M ≥ 6.0 occur in high-velocity zones or in the transitional areas between high-velocity and low-velocity zones in the upper crust. Seismicity in the low-velocity zone has a lesser impact. Earthquakes occuring in the high-velocity zone are distributed mainly in the velocity variation area. The boundary belts and the interior of the North China plain fault block are the main active sites of moderate-strong earthquakes. Beneath the fault basins in the western and northern sides of the block, the upper crust is characterized by a wide discontinuous distribution in the low-velocity zone, and in the transition zone from the low- to high velocities, the moderate strong seismicity shows a zonal distribution where active faults are developed. The NW-extension Zhoukou-Hefei-Xuancheng low-velocity zone separates the highvelocity zones of Dabieshan Mountains and west Shandong-Anhul, and moderate-strong earthquakes on its northern side bordering the high-velocity zones are relatively frequent. This low-velocity zone is probably an important and deeply structured boundary between the North China and the South China tectonic provinces. (2) The frequent moderate-strong earthquake recorded in the past and the recent small earthquake activities in the Huoshan-Lu' an area are the result of a low-velocity zone in the middle crust beneath the central part of Dabieshan and the two sets of deep faults that cut through the crust. (3) In terms of deep structures, the distribution of moderate-strong earthquake in Anhui Province has an obvious regional feature. Based on historical earthquake recurrence intervals and analogue principles of deep seismogenic tectonics, the potential earthquake risk zones recording Ms5.0 in Anhui Province are determined.展开更多
Many cases of foot-and-mouth disease (FMD) are reported every year in Benin. In order to elucidate the epidemiology of this disease, a space-time analysis was carried out in all the 77 municipalities of the country ai...Many cases of foot-and-mouth disease (FMD) are reported every year in Benin. In order to elucidate the epidemiology of this disease, a space-time analysis was carried out in all the 77 municipalities of the country aiming to identify high risk areas as well as risk factors such as season and transhumance on the period of 2005 to 2014. Data were collected retrospectively from the Directory of Animal Production of Benin. The method of Kulldorff was used with the software SaTScanTM for the space-time analysis while a script was designed in the software R to generate new sizes with three different models of transhumance. From 2005 to 2014, 434 foci were recorded. Many outbreaks occurred in August, September and October. This period corresponds to the small rainy season in the South and the rainy season of the North. The municipality of Parakou was regarded as the source FMD outbreaks in Benin because it hosts one of the largest livestock markets in the country and many rivers. It was the municipality at the highest risk. The other municipalities at risk were Nikki, Pèrèrè and Kalaléas well as Karimama (hosting the national parkW), Kouandé and Toucountouna located nearby Pendjari’s national park. This study revealed that the space-time configuration is real and the main factors of persistence and dissemination of FMD virus were national parks, classified forests and the livestock market of Parakou all located in the North. The variation of the number of cattle due to their transhumance from the North to the South did not influence the zones at risk. Therefore, Northern Benin is probably at high risk of FMD.展开更多
Background:Soil transmitted helminth(STH)infections still remain a notable health problem in resource-limited countries due to difficulties in the implementation of control measures.In Nigeria for instance,despite sev...Background:Soil transmitted helminth(STH)infections still remain a notable health problem in resource-limited countries due to difficulties in the implementation of control measures.In Nigeria for instance,despite several community-based and provincial reports,national data on prevalence,burdens and risk zones(RZs)for STH infections are lacking.Methods:The present study employed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)to determine the prevalence,distribution and RZs for STH infections among Nigerian children through a meta-analysis of data published between 1980 and 2015.Pooled prevalence estimate(PPE)was determined by the random-effects model while heterogeneity was evaluated using the Cochran’s Q-test.Results:A total of 18901 of the 34518 Nigerian children aged 0-17 years examined across 19 Nigerian states during the period under review were infected with one or more species of STHs.The overall PPE for STH infections was 54.8%(95%CI:54.2-55.3).PPEs for sub-groups ranged between 13.2%(95%CI:11.5-15.1)and 80.9%(95%CI:80.0-81.7).Highest PPEs for STH infections were observed among children within community settings(59.0%,95%CI:57.7-60.4)and school-aged children(54.9%,95%CI:54.3-55.5).Ascaris lumbricoides was the most prevalent species(44.6%,95%CI:44.0-45.2).Over 36%(15/41)of the studies were published from south-western Nigeria.South-western region was the only high risk zone(HRZ)for STH infections while the rest of the regions were low risk zones(LRZs).Conclusions:STH infections involving Ascaris lumbricoides,Strongyloides stercoralis,Trichuris trichiura and hookworms are highly prevalent across Nigeria.Strategic use of anthelmintics,health education and adequate sanitation,taking into account this epidemiologic information will help in the control of these infections in Nigeria.展开更多
基金Supported by The Science and Research Development Key Item of Hebei Meteorological Bureau(10ky02)~~
文摘By using the hailstone disaster data,the spatio-temporal distribution characteristics of hailstone in Shijiazhuang,the relationship between the hailstone disaster and the weather system,the hailstone path were analyzed.Moreover,the risk zoning of hailstone disaster in every county(city) of Shijiazhuang was done according to the occurrence frequency of hailstone.The results showed that the spatio-temporal distribution characteristics of hailstone in Shijiazhuang were obvious,and there were 3 main paths.The zones where the paths passed were also the high risk areas of hailstone occurrence.The research provided the scientific guidance for the adjustment of agricultural industrial structure and the defense of hailstone disaster.
文摘A model of debris flow risk zoning is carried out with momentum analysis of debris flow. This model zones the debris flow inundation fan with density and velocity calculated by numerical simulation. The risk classification standard is determined according to the ultimate bearing capacities of different structures under impacting. And the ultimate bearing capacities are tested by impact failure experiment of destruction. Two structures typical in Chinese mountain towns, reinforced concrete frame construction and brickwork with concrete, are chosen in the experiment. The model makes debris flow risk zoning quantitative and the results comparable widely. The results differ much from that of other methods especially in the identification of medium and low risk zones.
基金Supported by Project of Special Foundation for Outstanding Scientists of Beijing, China(No.20051D1100205)
文摘The occurrence of debris flow is affected by many factors. Risk zoning of debris flow plays a vital role in the early-warning and prediction of abrupt geological hazards, and exploration of new method is needed in the early-warning and prediction of geological hazards. The extension theory is a new method to solve contradiction matters. Based on extension theory, AHP and GIS, the risk zoning model of debris flow was established in this paper. The result of this research provides a new way in the risk zoning, early-warning and prediction of debris flow
基金China Special Fund for Meteorological Research in the Public Interest(201206045)
文摘Based on meteorological data including daily sunshine duration, temperature and precipitation from 97 meteorological stations in Hunan province during the period of 1981—2010, in combination with the field experiment in different places at different sowing dates, the precise climatic risk zoning of double cropping super rice cultivation has been studied by using the spatial interpolation method and other Geographical Information System(GIS)technologies. Three key climatic factors were selected including chilling in May, high temperature heat damage during July to early August and low temperature damage in autumn in this study. Furthermore, based on the analysis of climatic conditions suitable for double cropping super rice cultivation and climatic disasters, 8-22 ℃ active accumulated temperature, sunshine duration from late March to October, climatic risk index of the low temperature in autumn, and climatic risk index of chilling in May were selected as key climatic factors to study the precise agro-meteorological regionalization of double cropping super rice in Hunan province. The results showed that: the high-yielding zones of double cropping super rice in Hunan were mainly located in Zhuzhou, Hengyang, Yongzhou and Chenzhou City, the moderate-yielding zones were primarily located in the east and north reaches of Dongting Lake,together with most of Changsha, Zhuzhou and Xiangtan City, and other regions in Hunan were not suitable for double cropping super rice. These findings can provide valuable information for the large-scale cultivation of double cropping super rice in Hunan province.
基金Supported by Special Project of Science Research in Public ServiceIndustry(Meteorology),China(GYHY200906019)
文摘[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary (1951 to 2005) and The Yearbook of Meteorological Disaster in Anhui Province (2006 to 2009), we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment.
基金This study was supported by the National Key R&D Program of China(Grant No.2019YFC1510205)the National Basic Research Program of China(No.2015CB452806)and the Jiangsu Collaborative Innovation Center for Climate Change.
文摘Previous studies on typhoon disaster risk zoning in China have focused on individual provinces or small-scale areas and lack county-level results.In this study,typhoon disaster risk zoning is conducted for China’s coastal area,based on data at the county level.Using precipitation and wind data for China and typhoon disaster and social data at the county level for China’s coastal area from 2004 to 2013,first we analyze the characteristics of typhoon disasters in China’s coastal area and then develop an intensity index of factors causing typhoon disasters and a comprehensive social vulnerability index.Finally,by combining the two indices,we obtain a comprehensive risk index for typhoon disasters and conduct risk zoning.The results show that the maximum intensity areas are mainly the most coastal areas of both Zhejiang and Guangdong,and parts of Hainan Island,which is similar to the distribution of typhoon disasters.The maximum values of vulnerability in the northwest of Guangxi,parts of Fujian coastal areas and parts of the Shandong Peninsula.The comprehensive risk index generally decreases from coastal areas to inland areas.The high-risk areas are mainly distributed over Hainan Island,south-western Guangdong,most coastal Zhejiang,the coastal areas between Zhejiang and Fujian and parts of the Shandong Peninsula.
文摘Taking the rainstorm flood disaster of Huaihe River basin as the research object,according to the principles of risk assessment for natural disasters,starting from the fatalness of inducing factors and the vulnerability of hazard bearing body,the weight of each impact factor was calculated by using AHP. By using spatial analysis and statistical function of GIS,the integrated risk chart of rainstorm flood disaster in Huaihe River basin was obtained. The results showed that the high risk areas of rainstorm flood disaster in Huaihe River basin mainly distributed in the southern part of Henan,the central northern part of Anhui and eastern part of Jiangsu Province. Due to higher fatalness of inducing factors in southern Henan,there was high risk in the region. Central Anhui and east Jiangsu were not only high-fatalness zones but also high vulnerability zones of population and economy.
基金Supported by Natural Science Foundation of Educational Administration of Anhui Province(KJ2010B422)
文摘[Objective] The aim was to study the flood disaster risks in Anhui Province based on GIS. [Method] Taking country as basic unit, the 1∶ 250 000 basic geographic data in Anhui Province as basis, from the angle of flood disaster hazard and economic vulnerability, and by dint of the calculation of the weight of each impact factor with entropy-based fuzzy AHP method, flood risk assessment model was established to study the flood disaster risks zoning in Anhui Province. Using nearly 10 years of disaster information in Anhui Province, the flood risk zoning of Anhui Province was studied. And the risks evaluation results of flood disaster risks in Anhui Province in recent 10 years were checked. [Result] The regional difference of flood disaster in Anhui Province was large. The most serious area of flood disaster was in Lingquan in Fuyang and Lingbi in Huaibei. The risks degree degraded from south mountainous area in north Anhui Plain to the mountainous area of west Anhui Province, from Huaibei Plain to the hilly area of Jianghuai and mountainous area of south Anhui Province. The disaster situation in Anhui Province in recent 10 years suggested that the areas suffering from serious economic losses were in Lingbi, Guzheng and Huainan in the south part of Huaibei Plain. The places having serious agricultural crops damages were in Tangshan and Xiao County in Huaibei Plain. Besides, the Jingzhai area in the Dabieshan in west Anhui Province also had serious agricultural crops in Jinzhai. Other places had limited disaster-stricken impacts; the distribution of disaster-stricken population and impacted area of agricultural crops were basically consistent. Therefore, the risk evaluation of flood disaster of Anhui Province based on GIS was basically consistent with reality. [Conclusion] This GIS-based flood risk zoning method had good practicability.
文摘In this paper, from the differences to evaluate and manage the seismic uncertainty we analyzed the imperfection of determinant method and the Poisson model of probabilistic method in seismic risk analysis. Through studying and summarizing the relation of earthquake occurrence time, intensity and place, we deemed that the time uncertainty of earthquake occurrence interacts with that of space. We expressed the interaction with the concept of upbound earthquake occurrence number and deduced the Binomial model. The Binomial model can be applied in reflecting uncertainty of time and space. Comparing the determinant method and the Poisson model of probabilistic method with the Binomial model, we have got the idea that determinant and the Poisson model are two limits of the Binomial model. When the temporal-spatial uncertainty is infinity or infinitesimal, the binomial model tends to a determinant method and a Poisson model respectively. We also gave an approach to show the implied probability of intensity in the Earthquake intensity Zoning Map in China made in 1977. We also estimated the maximums of the implied probability of five high intensity areas in the Northern China.
文摘Based on data of agricultural drought situation and sown area of main crops in each county or district of the Sichuan Basin, the spatial distribution and probability of agricultural drought risk at different risk levels were studied using normal information diffusion method, and the risk zoning was carried out. The results showed that normal information diffusion method could fit the distribution of agricultural drought risk in the Sichuan Basin. By comparison with the end of the 20^th century, agricultural drought risk in Meishan, Chongqing City and so on increased at the beginning of the 21^st century when x1≥ 10% or x1≥40%. Agricultural drought risk was low in the west of the Sichuan Basin, which was related to rich precipitation here, but it was high in Bazhong, Zhongjiang, Luxian and so forth. The risk zoning results can provide scientific references for disaster prevention and emergency management of government.
基金Under the auspices of Major Basic Reseach Development Program of China (973 Program) (No. 2006CB403201)
文摘Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area (about 50.81%) was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found.
基金Under the auspices of the National Natural Science Foundation of China (No. 30270225 40331008) and Chinese Academy of Sciences (No. SCXZY0102)
文摘The Da Hinggan Mountains is one of the most important forest areas in China, but forest fire there is also of high frequency. So it is completely necessary to map forest fire risk zones in order to effectively manage and protect the forest resources. Two forest farms of Tuqiang Forest Bureau (53 degrees 34'-52 degrees 15'N,124 degrees 05'-122 degrees 18'E) were chosen as typical areas in this study. Remote sensing (RS) and Geographic Information System (GIS) play a vital role and can be used effectively to obtain and combine different forest-fire-causing factors for demarcating the forest fire risk zone map. Forest fire risk zones were described by assigning subjective weights to the classes of all the coverage layers according to their sensitivity to fire, using the ARC/INFO GIS software. Four classes of forest fire risk ranging from low to extremely high were generated automatically in ARC/INFO. The results showed that about 60.33% of the study area were predicted to be upper moderate risk zones, indicating that the forest fire management task in this area is super onerous. The RS and GIS-based forest fire risk model of the study area was found to be highly compatible with the actual fire-affected sites in 1987. Therefore the forest fire risk zone map can be used for guidance of forest fire management, and as basis for fire prevention strategies.
文摘The wrack or the ship out of control will drift with flow.One of the most important factors that drive the ship is flow current which moves circularly in tidal area.The wrack from same place always drifts in different ways if the start time is different.So,during the ship drifting period,the drift trace is also determined by both wave and wind forces.The drift direction is limited by water depth which must be deeper than ship draft. These marine structures that can not afford the hit of wrack or will destroy the wrack must be well considered when they are placed near harbor and waterway or other water area with ship running.The risk zone should be consulted according to tide and weather conditions to protect structures and ships in necessary.A method is presented here to simulate the risk zone by 2D numerical hydraulic model with tidal current,wave,wind and water depth considered.This model can be used to built early-warning and protect system for special marine structure.
基金jointly supported by National Science Foundation of China(41302171)Active Fault Exploration in China(60112304)Basic Scientific Research Funds of China Earthquake Administration(2014IES0401,2012IES010303)
文摘Since 2001, there have occurred in succession the 2001 Kunlun Mountains M S8. 1earthquake,the 2008 Wenchuan M S8. 0 earthquake,the 2010 Yushu M S7. 1 earthquake and the 2012 Lushan M S7. 0 earthquake in the periphery of the Bayan Har block. By comparison of the characteristics of seismic strain release variations before and after the Kunlun Mountains M S8. 1 earthquake in the same time length in the geodynamical related regions,we found that the seismic strain release was obviously enhanced after the earthquake in the Longmenshan area,Batang area,and the NS-trending valleys at the west of the Hot Spring Basin. The Wenchuan earthquake occurred in the first area,and the Yushu earthquake is related to the second area. After the earthquake rupture occurred on the East Kunlun fault zone on the northern boundary of the Bayan Har Block,crustal materials on the south side of the fault zone migrated to the southeast,leading to a concentration of tectonic deformation in the Longmenshan thrust belt, e ventually rupturing on the Longmenshan thrust belt. This earthquake case illustrates that seismicity enhancement zones are possibly prone to long-term destructive earthquakes. After the M S7. 3 earthquake in Yutian,Xinjiang on February 12,2014,earthquake frequency and seismic strain release markedly increased in the junction area between the eastern Qilian Mountain tectonic belt and the Altun Tagh fault zone,where more attention should be paid to the long-term seismic risk.
基金funded by the Key R&D Projects in Hainan Province (ZDYF2021SHFZ256)Natural Science Foundation of Hainan University,grant numbers KYQD (ZR)21,115
文摘Considerable economic losses and ecological damage can be caused by forest fi res,and compared to suppression,prevention is a much smarter strategy.Accordingly,this study focuses on developing a novel framework to assess forest fi re risks and policy decisions on forest fi re management in China.This framework integrated deep learning algorithms,geographic information,and multisource data.Compared to conventional approaches,our framework featured timesaving,easy implementation,and importantly,the use of deep learning that vividly integrates various factors from the environment and human activities.Information on 96,594 forest fi re points from 2001 to 2019 was collected on Moderate Resolution Imaging Spectroradiometer(MODIS)fi re hotspots from 2001 to 2019 from NASA’s Fire Information Resource Management System.The information was classifi ed into factors such as topography,climate,vegetation,and society.The prediction of forest fi re risk was generated using a fully connected network model,and spatial autocorrelation used to analyze the spatial aggregation correlation of active fi re hotspots in the whole area of China.The results show that high accuracy prediction of fi re risks was achieved(accuracy 87.4%,positive predictive value 87.1%,sensitivity 88.9%,area under curve(AUC)94.1%).Based on this,it was found that Chinese forest fi re risk shows signifi cant autocorrelation and agglomeration both in seasons and regions.For example,forest fi re risk usually raises dramatically in spring and winter,and decreases in autumn and summer.Compared to the national average,Yunnan Province,Guangdong Province,and the Greater Hinggan Mountains region of Heilongjiang Province have higher fi re risks.In contrast,a large region in central China has been recognized as having a long-term,low risk of forest fi res.All forest risks in each region were recorded into the database and could contribute to the forest fi re prevention.The successful assessment of forest fi re risks in this study provides a comprehensive knowledge of fi re risks in China over the last 20 years.Deep learning showed its advantage in integrating multiple factors in predicting forest fi re risks.This technical framework is expected to be a feasible evaluation tool for the occurrence of forest fi res in China.
文摘The homogeneous risk characteristics within a sub-area and the heterogeneous from one sub-area to another are unclear using existing environmental risk zoning methods. This study presents a new zoning method by determining and categorizing the risk characteristics using the k-means clustering data mining technology. The study constructs indices and develops index quantification models for environmental risk zoning by analyzing the mechanism of environmental risk occurrence. We calculate the source risk index, air risk field index, water risk field index, and target vulnerability of the study area with Nanjing Chemical Industrial Park using a 100 m - 100 m mesh grid as the basic zoning unit, and then use k-means clustering to analyze the environmental risk in the area. We obtain the optimal clustering number with the largest average silhouette coefficient by calculating the average silhouette coefficients of clustering at different k-values. The clustering result with the optimal clustering number is then used for the environmental risk zoning, and the zoning result is mapped using the geographic information system. The study area is divided into five sub-areas. The common environmental risk characteristics within the same sub-area, as well as the differences between sub- areas, are presented. The zoning is helpful in risk management and is convenient for decision makers to distribute limited resources to different sub-areas in the design of risk reducing intervention.
文摘Geohazards are a recurrent issue in the Kerio River catchment of Kenya, which usually results in life and property loss. This research focuses on mapping geo-hazard risk zones of the region. The risk zones were developed from a combination of land use land cover maps, agroecological zones maps and soil erosion maps using the Analytical Hierarchy Process method of multi-criteria analysis. The final results depict the geohazard risk maps which show the susceptibility of different areas in the catchment (classified as risk zones) to hazards. The zones range from no risk zones to very high-risk zones. The results showed that the lowlands are most susceptible to hazards as they were classified as high-risk zones. These risk zone areas have impacts on the socio-economic development hence negatively impacting livelihoods in the area.
基金The research was under the key science and technologyresearchfunds of the Earthquake Administration of Anhui Province ,China .
文摘Using the latest results of seismic tomography, we studied the deep tectonic settings of the moderate and strong earthquakes in Anhul Province and its neighboring areas (28° - 39°N, 112°- 124°E). The results are as follows: (1) There exists a certain correlation between the location of moderate-strong earthquake, the geologic structure of the surface and the partitioning of active tectonic elements with the upper-crust velocity structure. Most earthquakes recording M ≥ 6.0 occur in high-velocity zones or in the transitional areas between high-velocity and low-velocity zones in the upper crust. Seismicity in the low-velocity zone has a lesser impact. Earthquakes occuring in the high-velocity zone are distributed mainly in the velocity variation area. The boundary belts and the interior of the North China plain fault block are the main active sites of moderate-strong earthquakes. Beneath the fault basins in the western and northern sides of the block, the upper crust is characterized by a wide discontinuous distribution in the low-velocity zone, and in the transition zone from the low- to high velocities, the moderate strong seismicity shows a zonal distribution where active faults are developed. The NW-extension Zhoukou-Hefei-Xuancheng low-velocity zone separates the highvelocity zones of Dabieshan Mountains and west Shandong-Anhul, and moderate-strong earthquakes on its northern side bordering the high-velocity zones are relatively frequent. This low-velocity zone is probably an important and deeply structured boundary between the North China and the South China tectonic provinces. (2) The frequent moderate-strong earthquake recorded in the past and the recent small earthquake activities in the Huoshan-Lu' an area are the result of a low-velocity zone in the middle crust beneath the central part of Dabieshan and the two sets of deep faults that cut through the crust. (3) In terms of deep structures, the distribution of moderate-strong earthquake in Anhui Province has an obvious regional feature. Based on historical earthquake recurrence intervals and analogue principles of deep seismogenic tectonics, the potential earthquake risk zones recording Ms5.0 in Anhui Province are determined.
文摘Many cases of foot-and-mouth disease (FMD) are reported every year in Benin. In order to elucidate the epidemiology of this disease, a space-time analysis was carried out in all the 77 municipalities of the country aiming to identify high risk areas as well as risk factors such as season and transhumance on the period of 2005 to 2014. Data were collected retrospectively from the Directory of Animal Production of Benin. The method of Kulldorff was used with the software SaTScanTM for the space-time analysis while a script was designed in the software R to generate new sizes with three different models of transhumance. From 2005 to 2014, 434 foci were recorded. Many outbreaks occurred in August, September and October. This period corresponds to the small rainy season in the South and the rainy season of the North. The municipality of Parakou was regarded as the source FMD outbreaks in Benin because it hosts one of the largest livestock markets in the country and many rivers. It was the municipality at the highest risk. The other municipalities at risk were Nikki, Pèrèrè and Kalaléas well as Karimama (hosting the national parkW), Kouandé and Toucountouna located nearby Pendjari’s national park. This study revealed that the space-time configuration is real and the main factors of persistence and dissemination of FMD virus were national parks, classified forests and the livestock market of Parakou all located in the North. The variation of the number of cattle due to their transhumance from the North to the South did not influence the zones at risk. Therefore, Northern Benin is probably at high risk of FMD.
基金The author is grateful to the Editor-In-Chief of the Nigerian Journal of Parasitology for making available some of the articles included in the meta-analysis and to Mrs.Juliana Tije for helping in literature search.
文摘Background:Soil transmitted helminth(STH)infections still remain a notable health problem in resource-limited countries due to difficulties in the implementation of control measures.In Nigeria for instance,despite several community-based and provincial reports,national data on prevalence,burdens and risk zones(RZs)for STH infections are lacking.Methods:The present study employed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)to determine the prevalence,distribution and RZs for STH infections among Nigerian children through a meta-analysis of data published between 1980 and 2015.Pooled prevalence estimate(PPE)was determined by the random-effects model while heterogeneity was evaluated using the Cochran’s Q-test.Results:A total of 18901 of the 34518 Nigerian children aged 0-17 years examined across 19 Nigerian states during the period under review were infected with one or more species of STHs.The overall PPE for STH infections was 54.8%(95%CI:54.2-55.3).PPEs for sub-groups ranged between 13.2%(95%CI:11.5-15.1)and 80.9%(95%CI:80.0-81.7).Highest PPEs for STH infections were observed among children within community settings(59.0%,95%CI:57.7-60.4)and school-aged children(54.9%,95%CI:54.3-55.5).Ascaris lumbricoides was the most prevalent species(44.6%,95%CI:44.0-45.2).Over 36%(15/41)of the studies were published from south-western Nigeria.South-western region was the only high risk zone(HRZ)for STH infections while the rest of the regions were low risk zones(LRZs).Conclusions:STH infections involving Ascaris lumbricoides,Strongyloides stercoralis,Trichuris trichiura and hookworms are highly prevalent across Nigeria.Strategic use of anthelmintics,health education and adequate sanitation,taking into account this epidemiologic information will help in the control of these infections in Nigeria.