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基于用户浏览行为相似度的HTTP-Get Flood检测 被引量:1
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作者 陈虎 彭艳兵 《电视技术》 北大核心 2013年第7期104-106,共3页
针对日益泛滥的HTTP-Get Flood攻击,提出了利用用户浏览行为相似性界定HTTP-Get Flood攻击。详细阐述了用户浏览行为相似性的表述方法和检测算法的结构,通过下载公开的Trace对检测算法进行仿真及验证,结果表明,本算法能准确地检测出各... 针对日益泛滥的HTTP-Get Flood攻击,提出了利用用户浏览行为相似性界定HTTP-Get Flood攻击。详细阐述了用户浏览行为相似性的表述方法和检测算法的结构,通过下载公开的Trace对检测算法进行仿真及验证,结果表明,本算法能准确地检测出各种类型的HTTP-Get Flood攻击,很好地揭示攻击行为爆发的时间段,在HTTP-Get Flood攻击检测中有良好的应用。 展开更多
关键词 DDOS攻击 http-get flood 浏览行为相似度
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基于MIKE FLOOD耦合模型的城市暴雨洪涝模拟
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作者 李绍铭 金辉 +1 位作者 李鹏 刘俊国 《南水北调与水利科技(中英文)》 北大核心 2025年第5期1143-1152,共10页
应用MIKE 11、MIKE 21和MIKE URBAN模型分别构建山东大学黄台桥以上流域的一维和二维水动力学模型,采用MIKE 11中的NAM模型模拟研究区平原和山区的降雨-产流过程,借助MIKE FLOOD平台耦合模拟3场历史降雨和不同短历时、长历时设计降雨下该... 应用MIKE 11、MIKE 21和MIKE URBAN模型分别构建山东大学黄台桥以上流域的一维和二维水动力学模型,采用MIKE 11中的NAM模型模拟研究区平原和山区的降雨-产流过程,借助MIKE FLOOD平台耦合模拟3场历史降雨和不同短历时、长历时设计降雨下该区域的淹没积水特征,并讨论雨峰系数对淹没积水特征的影响规律。结果表明:经过模型率定与验证,纳什效率系数均在0.7以上,构建的耦合模型满足模拟精度需求;随着降雨重现期增加,淹没总面积呈上升趋势,且淹没水深范围较大的区域增加显著;降雨量相同时,长历时降雨由于存在2个雨峰,弱化了积水效应,淹没总面积相对短历时降雨较小;随着雨峰后移,淹没总面积增加,淹没水深超过0.2 m的区域显著增加,对内涝积水更为不利。相关结果可为研究区防洪减灾工作提供参考。 展开更多
关键词 暴雨 洪涝 MIKE flood 耦合模型 山东大学
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Authenticity of the Great Flood during the late Longshan era 被引量:1
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作者 NI Hantao TIAN Fei +5 位作者 HUAN Xiujia WANG Yong CHENG Jie YUAN Lupeng YAO Peiyi ZHANG Chunxia 《Journal of Geographical Sciences》 2025年第8期1714-1732,共19页
The historicity of China's first state-level government(the Xia Dynasty),during which a Great Flood is claimed to have swept through the core of northern China,remains a well-known yet unresolved issue.Archaeologi... The historicity of China's first state-level government(the Xia Dynasty),during which a Great Flood is claimed to have swept through the core of northern China,remains a well-known yet unresolved issue.Archaeologists hypothesize a connection between the legendary events of the Xia Dynasty and archaeological discoveries in the Central China Plains cultural area,encompassing late Neolithic and Bronze Age cultures such as Henan's Longshan,Xinzhai,Erlitou,and Erligang.The authenticity of these speculations has been challenging to substantiate due to the lack of systematic evidence for the Great Flood in the middle to lower Yellow River(YR)Basin.In this paper,we present high-resolution hydrological environmental proxy data,sedimentological remains,and paleontological evidence from the central North China Plain.Our findings provide isochronous evidence of the termination of a hundred-year-long flood period dated to approximately 2080±216 BC,consistent with the observations from lower YR flood plain and marginal marine sediments.These findings both spatially and temporally overlap with the framework of the Great Flood described in the Chinese classics.The alignment between the geoscientific and archaeological evidence and the information in the Chinese classics provides robust confirmation that the Great Flood occurred in the middle to lower YR region during the late Longshan era. 展开更多
关键词 North China Plain Great flood hydroclimatic and cultural evolution Longshan-Xinzhai-Erlitou archaeological sequence
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MIKE FLOOD在区域洪涝水位计算中的应用
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作者 宋靖 《云南水力发电》 2025年第4期156-159,共4页
MIKE Flood模型在城市洪涝分析管理中已得到广泛应用,软件模块丰富,功能齐全,对城市洪涝风险分析提供了理论依据和技术支持。文章主要根据某建设项目所在排水区域的地形、排水管网、周边河道等基础资料,利用MIKE FLOOD软件进行建模,耦... MIKE Flood模型在城市洪涝分析管理中已得到广泛应用,软件模块丰富,功能齐全,对城市洪涝风险分析提供了理论依据和技术支持。文章主要根据某建设项目所在排水区域的地形、排水管网、周边河道等基础资料,利用MIKE FLOOD软件进行建模,耦合计算区域设计工况下洪涝水位、淹没水深、淹没范围,并提出相应工作建议,为城市防灾减灾工作提供支持。 展开更多
关键词 MIKE flood 洪涝水位 洪涝风险 淹没水深
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基于Mike Flood模型的排涝工程体系调度策略
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作者 王梦军 《浙江水利水电学院学报》 2025年第3期40-44,50,共6页
以南昌市青山湖片区城市水系排涝系统为例,介绍了Mike Flood水力模型软件的重点内容及重要操作步骤,基于该软件进行建模,模拟青山湖泵站水位变化过程,对暴雨和非暴雨工况下泵站的运行和调度展开研究,进而得出南昌市青山湖片区排涝泵站... 以南昌市青山湖片区城市水系排涝系统为例,介绍了Mike Flood水力模型软件的重点内容及重要操作步骤,基于该软件进行建模,模拟青山湖泵站水位变化过程,对暴雨和非暴雨工况下泵站的运行和调度展开研究,进而得出南昌市青山湖片区排涝泵站的调度运行策略。实践表明该软件在城市水网控制性水闸、泵站、调度中具有一定参考意义。 展开更多
关键词 Mike flood 模型构建 运行调度 泵站
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基于Mike Flood的蒲河辽宁新民市段洪水淹没及防线布设应用
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作者 孙宇飞 《中国防汛抗旱》 2025年第4期80-84,共5页
以蒲河辽宁新民市段两岸防洪保护区为研究对象,运用Mike Flood模型对Mike11一维模型及Mike21二维模型进行耦合计算,根据河段防洪工程现状,模拟不同防洪标准及不同溃口条件下防洪保护区的洪水淹没情况。结合两岸防洪保护区基础设施情况,... 以蒲河辽宁新民市段两岸防洪保护区为研究对象,运用Mike Flood模型对Mike11一维模型及Mike21二维模型进行耦合计算,根据河段防洪工程现状,模拟不同防洪标准及不同溃口条件下防洪保护区的洪水淹没情况。结合两岸防洪保护区基础设施情况,进行第二道防线设置,并计算分析第二道防线设置情况下不同防洪标准保护区洪水淹没情况,以期为本河段及类似河段的防洪调度、洪水风险分析及防线布设提供技术支持及经验借鉴。 展开更多
关键词 洪水演进 防线布设 第二道防线设置 Mike flood 蒲河 辽宁新民市
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Flood frequency analysis and susceptibility zonation of the Haora River Basin,Northeast India
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作者 Asif Iqbal Shah Kirtica Das Nibedita Das Pan 《River》 2025年第1期116-133,共18页
Flooding remains one of the most destructive natural disasters,posing significant risks to both human lives and infrastructure.In India,where a large area is susceptible to flood hazards,the importance of accurate flo... Flooding remains one of the most destructive natural disasters,posing significant risks to both human lives and infrastructure.In India,where a large area is susceptible to flood hazards,the importance of accurate flood frequency analysis(FFA)and flood susceptibility mapping cannot be overstated.This study focuses on the Haora River basin in Tripura,a region prone to frequent flooding due to a combination of natural and anthropogenic factors.This study evaluates the suitability of the Log-Pearson Type Ⅲ(LP-Ⅲ)and Gumbel Extreme Value-1(EV-1)distributions for estimating peak discharges and delineates floodsusceptible zones in the Haora River basin,Tripura.Using 40 years of peak discharge data(1984-2023),the LP-Ⅲ distribution was identified as the most appropriate model based on goodness-of-fit tests.Flood susceptibility mapping,integrating 16 thematic layers through the Analytical Hierarchy Process,identified 8%,64%,and 26%of the area as high,moderate,and low susceptibility zones,respectively,with a model success rate of 0.81.The findings highlight the need for improved flood management strategies,such as enhancing river capacity and constructing flood spill channels.These insights are critical for designing targeted flood mitigation measures in the Haora basin and other flood-prone regions. 展开更多
关键词 analytic hierarchy process disaster management flood frequency analysis flood Risk flood susceptibility North East India VULNERABILITY
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New challenges of water disasters:Mechanisms,identification,and risks of abrupt transitions between drought and flood
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作者 Shan-shui Yuan Zi-yan Shi 《Water Science and Engineering》 2025年第3期259-261,共3页
In the context of climate change,the acceleration of the global water cycle has led to the emergence of abrupt transitions between drought and flood events,presenting a new challenge for flood and drought disaster mit... In the context of climate change,the acceleration of the global water cycle has led to the emergence of abrupt transitions between drought and flood events,presenting a new challenge for flood and drought disaster mitigation.Abrupt transitions between drought and flood refer to a phenomenon in which an extreme drought event quickly shifts to an extreme flood event,or vice versa,within a relatively short time span.This phenomenon disrupts the traditional spatiotemporal distribution patterns of water-related disasters,reflecting not only the extreme unevenness in the distribution of water resources but also the rapid alternation of the water cycle's evolution(He et al.,2016).Moreover,due to its suddenness,extremity,and complexity,it poses severe threats to human societies and ecosystems.Scientifically addressing abrupt transitions between drought and flood has thus become a new challenge in flood and drought disaster prevention. 展开更多
关键词 climate changethe flood spatiotemporal distribution patterns abrupt transitions drought flood acceleration global water cycle flood drought disaster mitigationabrupt transitions drought flood climate change abrupt transitions
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A Cost-Effective Flood Warning System for Small Urban Basins
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作者 Robert E.Criss Eric M.Stein 《Journal of Earth Science》 2025年第1期307-313,共7页
An effective warning system for flash floods along the upper River des Peres, a small urban stream in eastern Missouri, USA, is based on three enterprise-level, automated rain gauges.Because floods in this 25 km~2 bas... An effective warning system for flash floods along the upper River des Peres, a small urban stream in eastern Missouri, USA, is based on three enterprise-level, automated rain gauges.Because floods in this 25 km~2 basin develop rapidly and are commonly caused by small but intense thunderstorm cells, these rain gauges were necessarily deployed within the watershed, and immediate telemetry and processing of rainfall delivered in 5-minute intervals is required. Available data show that damaging floods in this area occur only 30 min to 3 h following the delivery of 38 mm of rainfall or more in a single hour. Water levels along this stream can rise more than 3 m/h. Since full deployment in Nov. 2021, our system has successfully predicted 3 significant floods with one false positive. 展开更多
关键词 urban floods flood warning water levels HYDROLOGY
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基于MIKE FLOOD耦合模型的城市内涝模拟及排水系统优化
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作者 王忠伟 《陕西水利》 2025年第6期21-24,共4页
短历时强降雨及暴雨极易造成城市低洼地区内涝灾害,对道路运行和生产生活造成严重威胁。为有效预防和处治城市内涝灾害,必须依托可靠技术对城市水文过程展开模拟分析,锁定关键致涝风险因素并优化排水系统。基于此,应用MIKE 21和MIKE Ur... 短历时强降雨及暴雨极易造成城市低洼地区内涝灾害,对道路运行和生产生活造成严重威胁。为有效预防和处治城市内涝灾害,必须依托可靠技术对城市水文过程展开模拟分析,锁定关键致涝风险因素并优化排水系统。基于此,应用MIKE 21和MIKE Urban模型展开待评估区域地表水流动及积滞程度快速评估,通过MIKE FLOOD耦合模型对极端暴雨情景下城市内涝过程展开模拟,并进行主要积水区排水管网瓶颈识别、优化,可作为城市积涝风险防治及水患解决的借鉴参考。 展开更多
关键词 MIKE flood耦合模型 城市内涝 积水历时 排水系统 管网优化
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Resident Perceptions of Nature-Based Solutions for Flood Mitigation in Phnom Penh,Cambodia
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作者 Sophanith So Reach Rim HyeMin Park 《Journal of Environmental & Earth Sciences》 2025年第3期240-252,共13页
Nature-based solutions(NBS)involve the sustainable maintenance,management,and restoration of natural or modified ecosystems.Flooding is a major problem in Phnom Penh,Cambodia,and has significant social and economic ra... Nature-based solutions(NBS)involve the sustainable maintenance,management,and restoration of natural or modified ecosystems.Flooding is a major problem in Phnom Penh,Cambodia,and has significant social and economic ramifications.This study tries to suggest creative solutions that support human welfare and biodiversity while simultaneously resolving social problems by adopting NBS.An online survey using convenience and snowball sampling was conducted to assess the openness of Phnom Penh residents to adopting NBS for flood mitigation in their homes or buildings.The survey investigated perceptions of NBS effectiveness based on previous knowledge and flood risk perception.Results revealed a strong correlation between perceived efficacy and willingness to adopt NBS.Specifically,flood risk perception and prior knowledge significantly influenced the perceived effectiveness of NBS.Key findings indicate that high installation and maintenance costs,lack of awareness,limited space,cultural factors,and perceived ineffectiveness are primary barriers to NBS adoption.Additionally,specific regional factors contribute to reluctance in certain areas of Phnom Penh.To overcome these barriers,the study recommends that the Cambodian government and other stakeholders invest in public education campaigns to raise awareness about the benefits of NBS.Financial incentives and subsidies should be provided to reduce the economic burden on residents.Furthermore,integrating NBS into urban planning and infrastructure development is crucial to enhance community resilience against floods. 展开更多
关键词 Nature-Based Solutions Pluvial flood flood Mitigation
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Flash flood disaster risk evaluation based on geographic detector and interval number ranking method
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作者 Xiao Liu Ronghua Liu +1 位作者 Xiaolei Zhang Qi Liu 《River》 2025年第2期162-176,共15页
Among natural disasters,flash floods are the most destructive events,causing signif-icant damage to the economy and posing a serious threat to human life and property.Comprehensive risk assessment of these sudden floo... Among natural disasters,flash floods are the most destructive events,causing signif-icant damage to the economy and posing a serious threat to human life and property.Comprehensive risk assessment of these sudden floods is a key strategy to mitigate their impact.Accurate analysis of flash flood hazards can greatly enhance prevention efforts and inform critical decision-making processes,ultimately improving our ability to protect communities from these fast-onset disasters.This study analyzed the driving forces of flash flood disaster-causing factors in Heilongjiang Province.Meanwhile,nine different categories of variables affecting the occurrence of flash floods were selected,and the degree of influence of each driving factor on flash floods was quantitatively analyzed,and the driving force analysis of the driving factors of flash floods in Hei-longjiang Province was carried out by using the geographic probe model.This paper employs an uncertainty approach,utilizing a statistical-based interval weight deter-mination technique for evaluation indices and a two-dimensional information-based interval number sorting method.These methodologies are combined to construct a comprehensive flash flood risk assessment model.On this basis,the model was implemented in six regions within China's Heilongjiang province to evaluate and prioritize flash flood risks.The resulting risk ranking for these areas was as follows:Bayan≻Shuangcheng≻Boli≻Suibin≻Hailun≻Yian.The findings demonstrate that the interval number-based evaluation method effectively handles uncertainty,providing a more reliable risk grading system.This approach,by leveraging modern scientific advances and risk quantification techniques,is crucial for improving disaster management and mitigating flash flood impacts. 展开更多
关键词 advantage degree function flash flood flash flood risk evaluation RANKING
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Investing in resilience:A long-term analysis of china’s flood protection strategies
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作者 Koji Watanabe Mikio Ishiwatari +2 位作者 Daisuke Sasaki Akiko Sakamoto Mikiyasu Nakayama 《Resilient Cities and Structures》 2025年第1期115-123,共9页
Investing in disaster risk reduction is crucial for minimizing the impacts of disasters.However,little is known about the factors that influence changes in investment levels over time.This study aims to identify the k... Investing in disaster risk reduction is crucial for minimizing the impacts of disasters.However,little is known about the factors that influence changes in investment levels over time.This study aims to identify the key socio-economic drivers behind increases and decreases in flood protection investment in People’s Republic of China(PRC).Such information is crucial for policy makers to justify flood investments.By analyzing data on flood protection expenditures,economic losses from floods,and other relevant indicators from 1980 to 2020,the study evaluates the relationship between investment and disaster impacts through the lens of the flood investment cycle model.It was found that the country succeeded in reducing flood damage because of increasing investment in flood protection.The results indicate that changes in PRC’s flood protection investment have been driven by three major factors:the occurrence of major disasters,the fiscal situation,and shifts in government policies.Investment tended to increase following large-scale events,such as the 1998 Yangtze River Basin flood and the 2008 Wenchuan earthquake,which prompted policy changes and renewed focus on DRR measures.Fiscal constraints limited investment in the 1990s,but reforms and stimulus measures improved the financial situation,enabling increased spending on flood protection.PRC’s experience in steadily reducing flood damage through sustained investment and policy commitment offers valuable lessons for other developing countries facing similar challenges. 展开更多
关键词 flood investment cycle Yangtze River PRC flood damage Economic losses Disaster risk reduction
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Case study of flood risk and vulnerability in the city of Atlanta-A social,economic,technical,and institutional perspective
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作者 Prerna Singh Adjo Amekudzi-Kennedy +5 位作者 Baabak Ashuri Ty Parrillo Derek Rizzi Russell Clark Brian Woodall Heejun Chang 《Resilient Cities and Structures》 2025年第2期1-13,共13页
The negative impacts of natural hazards on communities at all scales have been increasing.Floods comprise one such natural hazard that has emerged as one of the most destructive in the US and worldwide.While a lot of ... The negative impacts of natural hazards on communities at all scales have been increasing.Floods comprise one such natural hazard that has emerged as one of the most destructive in the US and worldwide.While a lot of damage is estimated in terms of the cost of rebuilding infrastructure and direct loss of economy,the negative impacts of such disruptions go beyond the physical infrastructure.The impact on(and of)the social and institutional framework is rarely examined in conjunction with the physical and technical aspects.This paper examines flood vulnerability and risk of a community at an intersection of social,ecological,technical,and intuitional perspectives,and presents a framework for a holistic flood vulnerability and risk assessment that has a strong foundation in all four aspects of a resilient community.The study builds on the existing risk,vulnerability,and hazard assessment approaches,and refines them with a holistic perspective.The study uses a mixed method approach with qualitative and quantitative methodologies to assess flood occurrence probabilities,vulnerability,and risk from the social,ecological,technical,and institutional perspectives.A case study of the City of Atlanta is conducted using the framework to assess the overall vulnerability and risk of the city.The results of this analysis show that the regions that have the highest probability of flood hazard occurrence also appear to have the highest social,ecological,and technical vulnerabilities in the Atlanta area.While the results are intuitive,the applications support a focus on holistic resilience building across these four criteria.This study is potentially useful to practitioners,researchers,government agencies,and community organizations working to mitigate flood risk particularly as this risk continues to evolve with the changing climate. 展开更多
关键词 RESILIENCE Infrastructure VULNERABILITY Inland flooding
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Analysis of a Mountain Flood Disaster Caused by a Rainstorm in Datong,Qinghai Province on August 18,2022 and Countermeasures
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作者 Liang XU Haichen JU +1 位作者 Pengliang ZHANG Bianbian ZHANG 《Meteorological and Environmental Research》 2025年第3期61-67,共7页
In the early hours of August 18 in 2022,a mountain flood disaster occurred in Datong Hui and Tu Autonomous County,Xining City,Qinghai Province,resulting in 31 deaths.This typical incident of multiple casualties result... In the early hours of August 18 in 2022,a mountain flood disaster occurred in Datong Hui and Tu Autonomous County,Xining City,Qinghai Province,resulting in 31 deaths.This typical incident of multiple casualties resulting from a mountain flood disaster caused by heavy precipitation.In this paper,the mountain flood disaster was analyzed from three aspects,the distribution of the observation station network,assessment of minute-level precipitation,and quantitative precipitation estimated by Xining radar data during August 17-18,2022.It aims to identify the critical gap in comprehensive monitoring systems,and explore effective monitoring methods and estimation algorithms of minute-level quantitative precipitation.Moreover,subsequent defense countermeasures were proposed.These findings offer significant guidance for enhancing meteorological disaster prevention capabilities,strengthening the first line of defense in disaster prevention and mitigation,and supporting evidence-based decision-making for local governments and flood control departments. 展开更多
关键词 Datong QINGHAI Mountain flood RAINSTORM
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Research on the Application of Emergency Management of Construction Engineering Enterprises in Flood Season Based on Dual-Control System
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作者 Rui Shi Jiejuan Liu 《Journal of Architectural Research and Development》 2025年第3期172-180,共9页
The building construction industry,recognized as one of the eight high-risk sectors,also serves as a crucial pillar of the national economy and a key source of employment.Major project advancements typically concentra... The building construction industry,recognized as one of the eight high-risk sectors,also serves as a crucial pillar of the national economy and a key source of employment.Major project advancements typically concentrate between April to June and September to November each year.However,construction progress tends to slow down during July and August due to increased rainfall associated with the flood season.The impact of the flood season on construction projects is primarily reflected in areas such as civil works,machinery and equipment,and temporary power supply.By establishing a dual-control emergency management system for the flood season,construction enterprises can enhance their emergency response capabilities,effectively reduce management challenges,and improve the overall efficiency of emergency handling. 展开更多
关键词 flood season Emergency management Dual-control system
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Urban Flood Risk Management Based on Asset Life Cycle Method for Drainage System: Case Study Gedebage Area, Bandung, Indonesia
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作者 Rani Gayatri Kusumawardhani Pradoto Eka Oktariyanto Nugroho +6 位作者 Hana Syakira Agung Budi Wicaksono Fatma Nurkhaerani Angga Trysa Yuherdha Cut Thias Enfila Regina Dio Oriandra Dimas Putra Wahyudi 《Journal of Environmental & Earth Sciences》 2025年第6期91-110,共20页
Flooding is a natural phenomenon influenced by various factors and occurs frequently across many regions in Indonesia,including Gedebage in Bandung City,West Java.Gedebage is one of the city’s lowest-lying areas,with... Flooding is a natural phenomenon influenced by various factors and occurs frequently across many regions in Indonesia,including Gedebage in Bandung City,West Java.Gedebage is one of the city’s lowest-lying areas,with an elevation of 666-669 meters above sea level,making it particularly prone to recurrent flooding.The main issue is the absence of an integrated disaster management system.This research aims to identify the drainage system’s asset life cycle(planning,implementation,and operation&maintenance)and assess flood risk in Gedebage.The risk assessment was conducted using questionnaires to evaluate the likelihood and potential impact of risks.In response to major risks,appropriate mitigation strategies were developed.Mitigation efforts included both structural and non-structural measures.The structural mitigation design involved selecting technological alternatives using the Analytical Hierarchy Process(AHP),a decision-making tool that helps compare multiple criteria and alternatives in a structured way.The results indicate that 27% of the assessed risks were unacceptable,42% undesirable,and 31% acceptable.Flood risk in Gedebage can be managed through structural actions,such as drainage revitalization using a closed system,and non-structural strategies,including human-centric,administrative,and cultural approaches.Based on AHP analysis,the most effective technology was a closed drainage system and porous paving blocks. 展开更多
关键词 Urban floods Risk Management MITIGATION
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Flood Mapping Methodologies in Google Earth Engine Using Optical and Radar Data: A Comparative Study
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作者 Yassine Loukili Younes Lakhrissi Safae Elhaj Ben Ali 《Journal of Environmental & Earth Sciences》 2025年第1期363-380,共18页
Floods are among the most severe and frequent natural disasters,impacting numerous countries worldwide.This study investigates flood mapping methodologies utilizing Google Earth Engine(GEE)with Sentinel-1,Sentinel-2,a... Floods are among the most severe and frequent natural disasters,impacting numerous countries worldwide.This study investigates flood mapping methodologies utilizing Google Earth Engine(GEE)with Sentinel-1,Sentinel-2,and Landsat data,focusing on the January 2021 Tetouan flood in Morocco.Three approaches were assessed:Sentinel-1 thresholding and NDWI(Normalized Difference Water Index)methods applied to Sentinel-2 and Landsat imagery.The analysis revealed flooded areas of 891 hectares(Sentinel-1),814 hectares(Sentinel-2),and 1237 hectares(Landsat),validated against ArcGIS(Geographic Information System)results estimating 900 hectares.Sentinel-1 demonstrated superior accuracy with only a 9-hectare deviation and proved effective under cloudy conditions.Sentinel-2 provided a balance between spatial resolution and error levels,with moderate commission and omission errors.Landsat detected the largest flood extent but exhibited a slight overestimation.The study emphasizes the advantages of GEE’s cloud-based platform,which significantly reduced processing time,facilitating rapid flood extent mapping.This scalability and efficiency make GEE an invaluable tool for disaster management.The results underline the potential of these methodologies for accurate and timely flood monitoring,enabling informed decision-making in resilience planning and emergency response.Such advancements are critical for mitigating the impacts of flooding and supporting sustainable disaster management strategies in vulnerable regions worldwide. 展开更多
关键词 flood Google Earth Engine Sentinel-1 Sentinel-2 LANDSAT
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Effects of soil labile carbon fractions and microbes on GHG emissions from flooding to drying in paddy fields
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作者 Yi Xiao Rong Huang +9 位作者 Zongjin Zhang Vanessa N.L.Wong Xingyu Li Xiaoyan Tang Youlin Luo Yingjie Wu Jiang Liu Shiwei Li Changquan Wang Bing Li 《Journal of Environmental Sciences》 2025年第12期420-434,共15页
Soil microorganisms and labile soil organic carbon(SOC)fractions are essential factors affecting greenhouse gas(GHG)emissions in paddy fields.However,the effects of labile SOC fractions and microorganisms on GHG emiss... Soil microorganisms and labile soil organic carbon(SOC)fractions are essential factors affecting greenhouse gas(GHG)emissions in paddy fields.However,the effects of labile SOC fractions and microorganisms on GHG emissions from flooding to drying after organic fertilizer replacing for chemical fertilizer remain unclear.Here,a long-term experiment was conducted with four treatments:chemical fertilization only(control),organic fertilizer substituting 25%of chemical N fertilizer(NM1),50%of chemical N fertilizer(NM2),and NM2combined with crop straw(NMS).GHG emissions were monitored,and soil samples were collected to determine labile SOC fractions and microorganisms.Results revealed the GHG emissions in the NM2 significantly increased by 196.88%from flooding to drying,mainly due to the higher CO_(2) emissions.The GHG emissions per kg of C input in NMS was the lowest with the value of 9.17.From flooding to drying,organic fertilizer application significantly increased the readily oxidizable organic carbon(ROC)contents and C lability;the NM2 and NMS dramatically increased the SOC and non-readily oxidizable organic carbon(NROC).The bacterial communities showed significant differences among different treatments in the flooding,while the significant difference was only found between the NMS and other treatments in the drying.From flooding to drying,changing soil moisture conditions causes C fractions and microbial communities to jointly affect carbon emissions,and the NMS promoted carbon sequestration and mitigated GHG emissions.Our findings highlight the importance of the labile SOC fractions and microorganisms linked to GHG emissions in paddy fields. 展开更多
关键词 Labile SOC fractions MICROORGANISMS GHG emissions flooding and drying
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Multi-source and multi-temporal remote sensing image classification for flood disaster monitoring
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作者 LI Zhu JIA Zhenyang +1 位作者 DONG Jing LIU Zhenghong 《Global Geology》 2025年第1期48-57,共10页
Flood disasters can have a serious impact on people's production and lives, and can cause hugelosses in lives and property security. Based on multi-source remote sensing data, this study establisheddecision tree c... Flood disasters can have a serious impact on people's production and lives, and can cause hugelosses in lives and property security. Based on multi-source remote sensing data, this study establisheddecision tree classification rules through multi-source and multi-temporal feature fusion, classified groundobjects before the disaster and extracted flood information in the disaster area based on optical imagesduring the disaster, so as to achieve rapid acquisition of the disaster situation of each disaster bearing object.In the case of Qianliang Lake, which suffered from flooding in 2020, the results show that decision treeclassification algorithms based on multi-temporal features can effectively integrate multi-temporal and multispectralinformation to overcome the shortcomings of single-temporal image classification and achieveground-truth object classification. 展开更多
关键词 MULTI-TEMPORAL decision tree classification flood disaster monitoring
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