Spatial–temporal characteristics and driving factors of flash floods in Shaanxi Province considering regional differentiation

Abstract Flash floods show strong regional differentiation in spatial–temporal distribution and driving forces, thereby hindering their effective prevention and control. This study analyzed the spatiotemporal characteristics of flash floods in Shaanxi Province, China, differentiated among the northern Shaanxi (NS), Guanzhong (GZ), and southern Shaanxi (SS) regions based on the Mann–Kendall, Theil–Sen Median, and standard deviation ellipse methods. The main factors driving disasters and their interactions in each region were then identified within the three categories of precipitation factor (PPF), surface environment factor, and human activity factor (HAF) based on a geographical detector. Finally, the differences in flash flood characteristics among the NS, GZ, and SS regions were analyzed. The results showed that flash floods in Shaanxi Province are greatly affected by the PPF and the HAF, although the spatial–temporal characteristics and disaster-causing factors were significantly different in each region. The regions were ranked according to the number and growth trends of flash floods as follows: SS > GZ > NS. Furthermore, flash floods were affected by multiple factors, with the interaction between factors acting as a driving force of flash floods. The results of this study can provide a reference for the management of flash floods under regional differentiation.

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The Spatiotemporal Distribution of Flash Floods and Analysis of Partition Driving Forces in Yunnan Province

Sustainability ◽

10.3390/su11102926 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2926 ◽

Cited By ~ 8

Author(s):

Junnan Xiong ◽

Chongchong Ye ◽

Weiming Cheng ◽

Liang Guo ◽

Chenghu Zhou ◽

...

Keyword(s):

Sensitivity Analysis ◽

Economic Development ◽

Return Period ◽

Driving Forces ◽

Flash Flood ◽

Temporal Distribution ◽

Heavy Precipitation ◽

Spatiotemporal Analysis ◽

Flash Floods

Flash floods are one of the most serious natural disasters, and have a significant impact on economic development. In this study, we employed the spatiotemporal analysis method to measure the spatial–temporal distribution of flash floods and examined the relationship between flash floods and driving factors in different subregions of landcover. Furthermore, we analyzed the response of flash floods on the economic development by sensitivity analysis. The results indicated that the number of flash floods occurring annually increased gradually from 1949 to 2015, and regions with a high quantity of flash floods were concentrated in Zhaotong, Qujing, Kunming, Yuxi, Chuxiong, Dali, and Baoshan. Specifically, precipitation and elevation had a more significant effect on flash floods in the settlement than in other subregions, with a high r (Pearson’s correlation coefficient) value of 0.675, 0.674, 0.593, 0.519, and 0.395 for the 10 min precipitation in 20-year return period, elevation, 60 min precipitation in 20-year return period, 24 h precipitation in 20-year return period, and 6 h precipitation in 20-year return period, respectively. The sensitivity analysis showed that the Kunming had the highest sensitivity (S = 21.86) during 2000–2005. Based on the research results, we should focus on heavy precipitation events for flash flood prevention and forecasting in the short term; but human activities and ecosystem vulnerability should be controlled over the long term.

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Spatiotemporal Characteristics and Driving Force Analysis of Flash Floods in Fujian Province

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi9020133 ◽

2020 ◽

Vol 9 (2) ◽

pp. 133 ◽

Cited By ~ 3

Author(s):

Junnan Xiong ◽

Quan Pang ◽

Chunkun Fan ◽

Weiming Cheng ◽

Chongchong Ye ◽

...

Keyword(s):

Driving Forces ◽

Flash Flood ◽

Principal Component ◽

Flash Floods ◽

Fujian Province ◽

Spatiotemporal Characteristics ◽

Middle Mountains ◽

Driving Force Analysis ◽

Economic Development Model ◽

The Impact

Flash floods are one of the most destructive natural disasters. The comprehensive identification of the spatiotemporal characteristics and driving factors of a flash flood is the basis for the scientific understanding of the formation mechanism and the distribution characteristics of flash floods. In this study, we explored the spatiotemporal patterns of flash floods in Fujian Province from 1951 to 2015. Then, we analyzed the driving forces of flash floods in geomorphic regions with three different grades based on three methods, namely, geographical detector, principal component analysis, and multiple linear regression. Finally, the sensitivity of flash floods to the gross domestic product, village point density, annual maximum one-day precipitation (Rx1day), and annual total precipitation from days > 95th percentile (R95p) was analyzed. The analytical results indicated that (1) The counts of flash floods rose sharply from 1988, and the spatial distribution of flash floods mainly extended from the coastal low mountains, hills, and plain regions of Fujian (IIA2) to the low-middle mountains, hills, and valley regions in the Wuyi mountains (IIA4) from 1951 to 2015. (2) From IIA2 to IIA4, the impact of human activities on flash floods was gradually weakened, while the contribution of precipitation indicators gradually strengthened. (3) The sensitivity analysis results revealed that the hazard factors of flash floods in different periods and regions had significant differences in Fujian Province. Based on the above results, it is necessary to accurately forecast extreme precipitation and improve the economic development model of the IIA2 region.

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Spatiotemporal Assessment of Land Marketization and Its Driving Forces for Sustainable Urban–Rural Development in Shaanxi Province in China

Sustainability ◽

10.3390/su13147755 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7755

Author(s):

Xindong Wei ◽

Ning Wang ◽

Pingping Luo ◽

Jie Yang ◽

Jian Zhang ◽

...

Keyword(s):

Rural Development ◽

Driving Forces ◽

Hot Spot ◽

Sustainable Use ◽

Shaanxi Province ◽

Use Of Resources ◽

Gray Relation Analysis ◽

Urban Rural ◽

Northern Shaanxi ◽

Southern Shaanxi

In recent years, market-oriented allocation of land has been promoted to support rural revitalization and urban–rural integrated development. To follow the path of sustainable development, it is necessary to improve the efficiency of resource utilization and to rationally allocate and use resources on the premise of ensuring the sustainable use of resources. This study aims to measure the degree of land marketization in Shaanxi Province, China during the period 2008–2019 and analyze its driving forces. The methods used include Gray Relation Analysis and Hot Spot Analysis. The MK trend method was used to analyze the average area of land acquired through Bidding–Listing–Auction (B-L-A), protocol, and allocation methods. The results show that the land marketization level in Shaanxi declined from 2008 to 2014 and fluctuated upwards from 2014 to 2019. In addition, B-L-A transactions increased across the province. There was little spatial heterogeneity of land marketization, but southern Shaanxi had less land marketization than the other key areas. Urbanization, non-agricultural output, and foreign direct investment were found to be the main driving factors of land marketization, while the influence of fixed asset investment and per capita disposable income declined each year. Based on these findings, we suggest that there is a need for land management reforms and urbanization efforts to encourage land marketization in southern Shaanxi. Further, we suggest that northern Shaanxi would benefit from optimizing the land use structure and focusing on the energy land market. This study also provides theoretical support for realizing the reform of the marketization of national land elements, the healthy operation of urban land marketization, and sustainable urban and rural development.

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A Temporally Varied Rainfall Simulator for Flash Flood Studies

10.1007/978-981-16-2904-4_10 ◽

2021 ◽

pp. 267-279

Author(s):

Mohammad Ebrahim Banihabib ◽

Bahman Vaziri

Keyword(s):

Numerical Model ◽

Flash Flood ◽

Experimental Studies ◽

Temporal Distribution ◽

Field Studies ◽

Flash Floods ◽

Flash Flooding ◽

Rainfall Simulator ◽

Natural Rainfall ◽

Precipitation Events

AbstractExperimental studies of flash floods require rainfall simulations. For this reason, various rainfall simulators have been designed, built, and employed in previous studies. These previous rainfall simulators have provided good simulations of constant rainfall intensities; however, these simulators cannot generate temporally varied rainstorms. Thus, the effect of the temporal distribution of a rainstorm on flash flooding cannot be studied using current rainfall simulators. To achieve accurate and reliable results in flash flood studies, simulating rainstorms that are similar to natural precipitation events is essential, and natural rainfall varies temporally. Thus, a rainstorm simulator was designed and built using cascading tanks to generate rainstorm hyetographs that cannot be obtained using traditional rainfall simulators. The result of the rainstorm generated by the proposed instrument and its numerical model showed that the instrument can simulate the temporal distributions of rainstorms with an accuracy of 95 percent. Consequently, the proposed instrument and its numerical model can be applied for generating artificial rainstorm hyetographs in experimental and field studies of flash floods.

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Spatial and Temporal Distribution Changes of Human Brucellosis in Inner Mongolia, China, effects of Husbandry and Control Measures

10.21203/rs.3.rs-135062/v1 ◽

2020 ◽

Author(s):

Jingbo Zhai ◽

qi zhang ◽

Ying Wang ◽

Dali Wang ◽

Lihua Song ◽

...

Keyword(s):

Inner Mongolia ◽

Prevention And Control ◽

Temporal Distribution ◽

Control Measures ◽

Human Brucellosis ◽

Spatial And Temporal Distribution ◽

Effective Prevention ◽

Policies And Measures ◽

Prevention And Control Measures ◽

And Control

Abstract BackgroundInner Mongolia has the highest incidence rate, causing great public health and economic losses. A number of policies to guide the prevention and control of human brucellosis had been issued and have made some achievements. Analysis of the distribution characteristics and changes of human brucellosis is important for the targeted prevention and control of this disease.MethodsWe collected various policies and measures related to brucellosis promulgated, and comprehensively analyzed the spatial and temporal distribution of human brucellosis in Inner Mongolia from 2005 to 2019 using the Bayesian theory of space-time modeling. ResultsWith the implementation of various policies and measures, great achievements have been made and distribution trends changed. Some western regions have changed into stable or cold-spot counties, and most cities in the eastern region have become hot-spot counties during the time period. The rising trend of risk in three cities is slowing down, while the risk in two cities is growing faster than the overall trend.ConclusionThe effective prevention and control measures are essential. The analysis results of this study may provide a theoretical and scientific basis for the public health department to develop targeted effective prevention and control measures for human brucellosis.

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Hydrogeomorphological analysis and modelling for a comprehensive understanding of flash-flood damage processes: the 9 October 2018 event in northeastern Mallorca

Natural Hazards and Earth System Science ◽

10.5194/nhess-20-2195-2020 ◽

2020 ◽

Vol 20 (8) ◽

pp. 2195-2220

Author(s):

Joan Estrany ◽

Maurici Ruiz-Pérez ◽

Raphael Mutzner ◽

Josep Fortesa ◽

Beatriz Nácher-Rodríguez ◽

...

Keyword(s):

Global Change ◽

Flash Flood ◽

Warning System ◽

Flash Floods ◽

Flood Damage ◽

Hydrological Modelling ◽

Mitigation Measures ◽

Management Service ◽

Catchment Scale ◽

Effective Prevention

Abstract. A flash-flood event hit the northeastern part of Mallorca on 9 October 2018, causing 13 casualties. Mallorca is prone to catastrophic flash floods acting on a scenario of deep landscape transformation caused by Mediterranean tourist resorts. As global change may exacerbate devastating flash floods, analyses of catastrophic events are crucial to support effective prevention and mitigation measures. Field-based remote-sensing and modelling techniques were used in this study to evaluate rainfall–runoff processes at the catchment scale linked to hydrological modelling. Continuous streamflow monitoring data revealed a peak discharge of 442 m3 s−1 with an unprecedented runoff response. This exceptional behaviour triggered the natural disaster as a combination of heavy rainfall (249 mm in 10 h), karstic features and land cover disturbances in the Begura de Salma River catchment (23 km2). Topography-based connectivity indices and geomorphic change detection were used as rapid post-catastrophe decision-making tools, playing a key role during the rescue search. These hydrogeomorphological precision techniques were combined with the Copernicus Emergency Management Service and “ground-based” damage assessment, which showed very accurately the damage-driving factors in the village of Sant Llorenç des Cardassar. The main challenges in the future are to readapt hydrological modelling to global change scenarios, implement an early flash-flood warning system and take adaptive and resilient measures on the catchment scale.

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Spatial and Temporal Distribution of Geologic Hazards in Shaanxi Province

Remote Sensing ◽

10.3390/rs13214259 ◽

2021 ◽

Vol 13 (21) ◽

pp. 4259

Author(s):

Shizhengxiong Liang ◽

Dong Chen ◽

Donghuan Li ◽

Youcun Qi ◽

Zhanfeng Zhao

Keyword(s):

Wenchuan Earthquake ◽

Debris Flows ◽

Temporal Distribution ◽

Shaanxi Province ◽

Impact Factors ◽

Dominant Factor ◽

2008 Wenchuan Earthquake ◽

The North ◽

Northern Shaanxi ◽

Spatio Temporal

The spatio-temporal distribution of geological hazards, including collapses, landslides, and debris flows, in Shaanxi province, China was studied based on data from 1951 to 2018. The potential impact factors, including the geomorphologic types, rivers, roads, rainfall, and earthquakes, were analyzed using Random Forests. The results indicated that most hazards occurred in summer (i.e., July–September) and were triggered by rainstorms. The freeze–thaw effect had a considerable contribution to hazards in the north. Spatially, most hazards in the north occurred in valley terraces of the Loess Plateau, while medium-relief terrane (relief ranged from 500 to 1000 m) in the southern Qinling Mountains were hazard-prone areas. The collapses and landslides were mainly affected by human factors in Northern Shaanxi, whereas in Southern Shaanxi geomorphology was the primary factor. Permeability was a dominant factor for debris flows. In addition, the 2008 Wenchuan earthquake had a remarkable influence on the spatial distribution of hazards. In contrast, for the situation in the Sichuan province, which was close to the earthquake epicenter, the Wenchuan earthquake triggered many collapse and landslide events in the southwest regions of Shaanxi province only on 12 May 2008. The thresholds for the three hazard types in the north and south regions were almost the same despite their distinctly different geologic characteristics. Through a sensitivity analysis, we found an appropriate dry period of 12 h for the area.

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Hydrogeomorphological analysis and modelling for a comprehensive understanding of flash-flood damaging processes: The 9th October 2018 event in North-eastern Mallorca

10.5194/nhess-2019-304 ◽

2019 ◽

Author(s):

Joan Estrany ◽

Maurici Ruiz-Pérez ◽

Raphael Mutzner ◽

Josep Fortesa ◽

Beatriz Nácher-Rodríguez ◽

...

Keyword(s):

Global Change ◽

Flash Flood ◽

Warning System ◽

Flash Floods ◽

Hydrological Modelling ◽

Mitigation Measures ◽

Catchment Scale ◽

Effective Prevention ◽

Flood Warning ◽

Karstic Features

Abstract. A flash-flood event hit in the 9th October 2018 the northeastern part of Mallorca Island, causing 13 casualties. This island is prone to catastrophic flash floods acting on a scenario that illustrates the deep landscape transformation of Mediterranean tourist resorts. As global change may exacerbate devastating flash floods, comprehensive analyses of catastrophic events are crucial to support effective prevention and mitigation measures. Field-based, remote-sense and modelling techniques were used in this study to evaluate rainfall-runoff processes at catchment scale linked to hydrological modelling. Continuous streamflow monitoring data revealed a peak discharge 442 m3 s−1 with an unprecedented runoff response (lag time, 15’). This very flashy behaviour triggered the natural disaster as a combination of heavy rainfall (246 mm in 10 h), karstic features and land cover disturbances in the Begura de Saumà River catchment (i.e., 23 km2). Topography-based connectivity index and geomorphic change detection were used as a rapid post-catastrophe decision-making tool, playing a key role during the rescue searching tasks. These hydrogeomorphological precision techniques were also applied in combination with Copernicus EMS and ground-based damage assessment illustrating with high accuracy the damage driving factors in the village of Sant Llorenç des Cardassar. The main challenges in the future are to readapt hydrological modelling to global change scenarios, implement an early flash flood warning system and apply adaptive and resilient measures at catchment scale.

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