Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in re...Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in response to transient pore pressure by means of transient and unsaturated rainfall infiltration modeling. A case study is performed on the shallow landslide stability analysis in Hong Kong. Detailed analysis and discussion reached some useful conclusions on the tempo-spatial behavior and characteristics of slope stability response and pore pressure response to typical rainfall process. Comparison analysis is performed on some important issues including landslide stability response in different types of slopes with different hydraulic properties, antecedent rainfall and landslide stability, and the nature of pore pressure response time. These studies might give us an important insight into landslide tringgering mechanism and the hydrological process in response to rainfall, and provide systematic information and evidences for effective risk assessment and warning system establishment.展开更多
Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal pre...Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4 grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.展开更多
Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide ...Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide over the slip surface at different heights of the model slopes, as well as taking the whole slope to identify its deformation and failure processes. The results show that the rainfall duration corresponding to the initiation of the debris landslide and is exponentially related to rainfall intensity. Corresponding to the three intervals of the rainfall intensity, there are three types of slope failure modes:(1) the small-slump failure at the leading edge of the slope;(2) the block-slump failure but sometimes there are large blocks sliding down;and(3) the bulk failure but sometimes there is the block-slump failure. Based on the total rainfall-lasting time and the associated proportion of failed mass volume, the early warning of debris landslide can be classified into five grades, i.e., red, orange to red, orange, yellow to orange and yellow, which correspond to the five slope failure modes, respectively.展开更多
Based on analysis and simulation,the interaction of thermal forcing between the Tibetan Plateau(TP) and Iranian Plateau(IP) in summer is investigated.Associated influences on water vapor transport in the Asian subtrop...Based on analysis and simulation,the interaction of thermal forcing between the Tibetan Plateau(TP) and Iranian Plateau(IP) in summer is investigated.Associated influences on water vapor transport in the Asian subtropical monsoon region and the formation of a cold center in the lower stratosphere over Eurasia are also investigated.Results show that surface sensible heating(SH) over the two plateaus not only have mutual influences but also feedback to each other.SH over the IP can reduce the SH and increase the LH over the TP,whereas the SH over the TP can increase surface heating over the IP,thereby reaching quasi-equilibrium among the SH and LH over the TP,IP SH and atmosphere vertical motion.Therefore,the so-called Tibetan-Iranian Plateau coupling system(TIPS) is constructed,which influences atmosphere circulation.In the TIPS system,interaction between surface SH and LH over the TP plays a leading role.SH of the IP and TP influences on other regions not only have superimposed effects but also mutually offset.Accounting for contributions to the convergence of water vapor transport in the Asian subtropical monsoon region,TP SH contributes more than twice that of the IP.The combined influence of SH over TP and IP represents the major contribution to the convergence of water vapor transport in that region.In addition,the heating effect of TIPS increases the upper tropospheric temperature maximum and lifts the tropopause,cooling the lower stratosphere.Combined with large-scale thermal forcing of the Eurasian continent,the TIPS produces a strong anticyclonic circulation and the South Asian High that warms the upper troposphere and cools the lower stratosphere,thereby affecting regional and global weather and climate.展开更多
Most rainfall-induced landslide forecasting models focus on the relation between landslides and rainfall,which is one of the dynamic factors,and seldom consider the stacitc factors,such as geological and geograpical f...Most rainfall-induced landslide forecasting models focus on the relation between landslides and rainfall,which is one of the dynamic factors,and seldom consider the stacitc factors,such as geological and geograpical factors.Landslide susceptibility,however,is determinded by both static and dynamic factors.This article proposes a static and dynamic factors-coupled forecasting model(SDFCFM) of regional rainfall-induced landslides,which quantitatively considers both the static and dynamic factors that affect landslides.The generalized additive model(GAM) is applied to coupling both factors to get the landslide susceptibility.In the case study,SDFCFM is applied to forecast the landslide occurrences in Shenzhen during a rainfall process in 2008.Compared with the rainfall logistic regression model,the resulting landslide susceptibility map illustrates that SDFCFM can reduce the forecast redundancy and improve the hit ratio.It is both applicable and practical.The application of SDFCFM in landslide warning and prevention system will improve its efficiency and also cut down the cost of human and matreial resources.展开更多
Rainwater runoff that does not infiltrate the soil during heavy rainfall may increase slope instability. The effect of runoff is usually neglected in conventional rainfall-induced slope failure analysis to simplify th...Rainwater runoff that does not infiltrate the soil during heavy rainfall may increase slope instability. The effect of runoff is usually neglected in conventional rainfall-induced slope failure analysis to simplify the model. To analyze the effect of runoff on slope stability, this study simultaneously simulated the effects of surface runoff and rainfall infiltration on bank slopes in the Three Gorges Reservoir Area. A shallow slope failure method that can be used to analyze runoff was proposed based on the modified Green-Ampt model, the simplified Saint-Venant model, and the infinite slope model. In this model, the modified Green–Ampt model was used to estimate the rainfall infiltration capacity and the wetting front depth. The eight-flow(D8) method and the simplified Saint-Venant model were selected to estimate the distribution of runoff. By considering the wetting front depth as the slip surface depth, the factor of safety of the slope could be determined using the infinite slope stability model. A comparison of the different models reveals that runoff can escalate the instability of certain slopes, causing stable slopes to become unstable. Comparison of the unstable areas obtained from the simulation with the actual landslide sites shows that the model proposed in this study can successfully predict landslides at these sites. The slope instability assessment model proposed in this study offers an alternative approach for estimating high-risk areas in large mountainous regions.展开更多
There is no doubt that land cover and climate changes have consequences on landslide activity,but it is still an open issue to assess and quantify their impacts.Wanzhou County in southwest China was selected as the te...There is no doubt that land cover and climate changes have consequences on landslide activity,but it is still an open issue to assess and quantify their impacts.Wanzhou County in southwest China was selected as the test area to study rainfall-induced shallow landslide susceptibility under the future changes of land use and land cover(LULC)and climate.We used a high-resolution meteorological precipitation dataset and frequency distribution model to analyse the present extreme and antecedent rainfall conditions related to landslide activity.The future climate change factors were obtained from a 4-member multimodel ensemble that was derived from statistically downscaled regional climate simulations.The future LULC maps were simulated by the land change modeller(LCM)integrated into IDRISI Selva software.A total of six scenarios were defined by considering the rainfall(antecedent conditions and extreme events)and LULC changes towards two time periods(mid and late XXI century).A physically-based model was used to assess landslide susceptibility under these different scenarios.The results showed that the magnitude of both antecedent effective recharge and event rainfall in the region will evidently increase in the future.Under the scenario with a return period of 100 years,the antecedent rainfall in summer will increase by up to 63%whereas the event rainfall will increase by up to 54%for the late 21st century.The most considerable changes of LULC will be the increase of forest cover and the decrease of farming land.The magnitude of this change can reach+22.1%(forest)and–9.2%(farmland)from 2010 until 2100,respectively.We found that the negative impact of climate change on landslide susceptibility is greater than the stabilizing effect of LULC change,leading to an over decrease in stability over the study area.This is one of the first studies across Asia to assess and quantify changes of regional landslide susceptibility under scenarios driven by LULC and climate change.Our results aim to guide land use planning and cli展开更多
Landslide is a geological hazard typically associated with extreme events such as earthquakes,heavy rainfall,volcanic eruptions,changes in groundwater level,etc.This study was carried out in Okemesi-Ekiti(also known a...Landslide is a geological hazard typically associated with extreme events such as earthquakes,heavy rainfall,volcanic eruptions,changes in groundwater level,etc.This study was carried out in Okemesi-Ekiti(also known as Okemesi),Southwest Nigeria,with the purpose of using remote sensing and GIS technologies to analyze the environmental factors(grain size,direct shear strength resistance,rainfall data,wet density,surface,and slope)resulting in the occurrence of the Okemesi landslide.The study also aimed to conduct a vulnerability analysis in the study area to identify regions with a probability of landslide occurrence.The grain size analysis of the soil in the Okemesi landslide area showed that slope materials comprised 17.14%gravel,59.31%sand,and 19.48%fines,thus the soil type could be classified as poorly graded gravely sand with a high possibility of landslide occurrence.The geomorphic characteristics of the study area was characterized by slopes ranging from 0.00°to 49.00°,while most slopes in the area were less than 8.00°.The slope aspect direction was mainly in south(157.51°–202.50°),southwest(202.51°–247.50°),west(247.51°–292.50°),and north(0.00°–22.50°and 337.51°–360.00°).The highlands were primarily bounded by the slope directions of north(0.00°–22.50°and 337.51°–360.00°),northeast(22.51°–67.50°),east(67.51°–112.51°),and southeast(112.51°–157.50°),which indicated the potential direction of mass movement.The study area can be divided into three vulnerability zones:high,medium,and low,with the area percentages of 9.00%,61.80%,and 29.20%,respectively.The analysis suggested that the Okemesi landslide was likely triggered by rainfall,which might have weakened the physical structure of slope materials.Understanding the causes and impacts of landslides is crucial for policymakers to implement measures to mitigate landslide hazards,protect infrastructure,and prevent the loss of life in the landslide-prone regions.展开更多
Landslides in the Himalayan region are primarily controlled by natural parameters,including rainfall,seismic activity,and anthropogenic parameters,such as the construction of large-scale projects like road development...Landslides in the Himalayan region are primarily controlled by natural parameters,including rainfall,seismic activity,and anthropogenic parameters,such as the construction of large-scale projects like road development,tunneling and hydroelectric power projects and climate change.The parameters which are more crucial among these are a matter of scientific study and analysis.This research,taking Solan district,Himachal Pradesh,India,as the study area,aims to assess the impact of anthropogenic activities on landslide susceptibility at a regional scale.Landslide distribution was characterized into two groups,namely Rainfall-Induced Landslide(RIL)and Human-Induced Landslide(HIL)based on triggering factors.Multiple data such as slope angle,aspect,profile curvature,distance to drainage,distance to lineament,lithology,distance to road,normalized difference vegetation index(NDVI)and land use land cover(LULC)have been considered for delineating the landslide susceptibility zonation(LSZ)map.The effect of anthropogenic activities on landslide occurrences has been examined through the distribution of landslides along national highways and land use land cover changes(LULCC).Two sets of LSZ maps with a LULC of time interval covering five years(2017&2021)were prepared to compare the temporal progression of LULC and landslide susceptibility during the five years.The results indicated the significant impact of anthropogenic activities on the landslide susceptibility.LSZ map of the year 2021 shows that 23%area falls into high and very high susceptible classes and 48%area falls into very low and low susceptibility classes.Compared to LSZ map of 2017,high and very high susceptible classes have been increased by 15%,whereas very low and low susceptible classes have been reduced by 7%.The present case study will help to understand the potential driving parameters responsible for HIL and also suggest the inclusion of LULC in landslide susceptibility analysis.The study will demonstrate new opportunities for research that could help decis展开更多
Various rainfall factors,which affect the activities of rainfall-induced debris flow,are discussed in this paper.The factors include antecedent precipitation,current precipitation,rainfall duration,intensity,peak,and ...Various rainfall factors,which affect the activities of rainfall-induced debris flow,are discussed in this paper.The factors include antecedent precipitation,current precipitation,rainfall duration,intensity,peak,and rainfall pattern.Rainfall-induced debris flow is trigged by the co-action of current rainfall and antecedent rainfall.The advanced system of precipitation monitoring and forecasting in the rainfall-induced debris flow forecast system is established,which consists of four methods-numerical weather prediction,stationary meteorological satellite,weather radar echo and automatic weather station.Since the forecast of rainfall-induced debris flow is based on the prediction of precipitation,the prediction models objectively require more detailed and precise prediction products,which put forward a new research subject for meteorologists.展开更多
In this study, strength softening models are developed for exploring rainfall-induced landslide mechanism based on Mohr Coulomb strength theory with both saturation degree and temporal evolution into consideration. Ac...In this study, strength softening models are developed for exploring rainfall-induced landslide mechanism based on Mohr Coulomb strength theory with both saturation degree and temporal evolution into consideration. According to the ratio of two time scales available, the model can be classified into three categories, i.e., instant softening model, delay softening model, and coupling softening model. Corresponding evolution functions are specified to represent these kinds of softening processes and then applied to simulate landslide of homogeneous slopes triggered by rainfall, therefrom, useful conclusions can be drawn in the end.展开更多
In order to investigate the spatial distribution of early warning threshold for landslide induced by rainfall in China,the literatures about rainfall thresholds of landslides in China in recent 20 years are selected.S...In order to investigate the spatial distribution of early warning threshold for landslide induced by rainfall in China,the literatures about rainfall thresholds of landslides in China in recent 20 years are selected.Statistical analysis and visualization methods were employed to systematically analyze the research progress of rainfall early warning thresholds at various scales.Taking the typical rainfall intensity-duration(I-D)threshold model as the research object,combined with the geographical characteristics of China and the average annual rainfall of 20 years,the spatial distribution of early warning thresholds for rainfall-induced landslide in China is depicted.The results show that the inspired rain intensity coefficientαof the rainfall threshold(I-D curve)in China roughly increases gradually with the decrease of topography.Moreover,under consistent annual rainfall conditions,the scalar indexβexhibits regular changes corresponding to variations in terrain.Topography and rainfall are the two main factors strongly associated with the rainfall threshold.This research establishes a clear framework for studying the early warning thresholds for rainfall-induced landslides in China and holds significant scientific implications for developing more effective rainfall threshold models.展开更多
In recent years,RS and GIS technologies have played an increasingly important role in various aspects of rainfall induced landslide research.In order to systematically understand their application situation,this paper...In recent years,RS and GIS technologies have played an increasingly important role in various aspects of rainfall induced landslide research.In order to systematically understand their application situation,this paper extensively used various visualization analysis technologies for in-depth analysis of 1,161 documents collected by the WOS data platform in the past 27 years by combining quantitative and qualitative methods.Then,this article focuses on sub domain analysis from four aspects:landslide detection and monitoring,prediction models,sensitivity mapping,and risk assessment.The study found that the number of literature in thisfield has steadily increased and is expected to continue to rise.This literature review has attracted widespread attention from the academic community,but it challenging to meet research needs.Frequent and effective cooperationis between countries,institutions,and authors is very beneficial for promoting progress in thisfield.The future development direction is a new intelligent hybrid model that integrates multiple research methods.This study can provide researchers in thisfield with the core research force,hot topic evolution,and future development trends of future rainfall-induced landslides and contribute to landslide prevention and control decision-making and achieving the United Nations’sustainable development goals.展开更多
Rainfall is one of the most important factors contributing to landslides, and gentle bedding incline, high-rainfall induced landslides are common throughout the world. Field observations and theoretical analyses have ...Rainfall is one of the most important factors contributing to landslides, and gentle bedding incline, high-rainfall induced landslides are common throughout the world. Field observations and theoretical analyses have been used to assess slope instability caused by permeability variation. In this study, the influence of rainfall infiltration on gentle bedding incline slope behaviour was investigated using a centrifuge physical simulation test. The magnitude, pattern and development of pore water and earth pressure at the interface;the shear failure surface features;and the corresponding deformation and failure processes were considered. A model with interbedded sand and mud was created, and a centrifuge was used to simulate both natural and rainfall conditions. The weak intercalation was composed of single-material silty clay, and the landslide mass was composed of red-bed sandstone. A combination of photography, pore water pressure measurements and earth pressure measurements were used to examine the relationship between the pore water pressure, earth pressure and failure modes. When the slope experiences overall instability, the curves of the earth pressure and pore water pressure dramatically decrease. The results reveal that the failure shear surface largely depends on the differential creep caused by the properties of the rock mass and the rainfall infiltration.展开更多
The simulation of slope failures,including both failure initiation and development,has been modelled using the material point method（MPM）.Numerical case studies involving various slope angles,heterogeneity and rainf...The simulation of slope failures,including both failure initiation and development,has been modelled using the material point method（MPM）.Numerical case studies involving various slope angles,heterogeneity and rainfall infiltration are presented.It is demonstrated that,by utilising a constitutive model which encompasses,in a simplified manner,both pre-and post-failure behaviour,the material point method is able to simulate commonly observed failure modes.This is a step towards being able to better quantify slope failure consequence and risk.展开更多
Physical models used toforecast the temporal occurrence of rainfall-induced shallow landslides are based on deterministic laws.Owing to the existing measuring technology and our knowledge of the physical laws controll...Physical models used toforecast the temporal occurrence of rainfall-induced shallow landslides are based on deterministic laws.Owing to the existing measuring technology and our knowledge of the physical laws controlling landslide initiation,model uncertainties are due to an inability to accurately quantify the model input parameters and rainfall forcing data.An uncertainty analysis of slope instability prediction provides a rationale for refining the geotechnical models.The Transient Rainfall Infiltration and Grid-based Regional Slope Stability-Probabilistic(TRIGRS-P)model adopts a probabilistic approach to compute the changes in the Factor of Safety(FS)due to rainfall infiltration.Slope Infiltration Distributed Equilibrium(SLIDE)is a simplified physical model for landslide prediction.The new code(SLIDE-P)is also modified by adopting the same probabilistic approach to allow values of the SLIDE model input parameters to be sampled randomly.This study examines the relative importance of rainfall variability and the uncertainty in the other variables that determine slope stability.The precipitation data from weather stations,China Meteorological Administration Land Assimilation System 2.0(CLDAS2.0),China Meteorological Forcing Data set precipitation(CMFD),and China geological hazard bulletin are used to drive TRIGRS,SLIDE,TRIGRS-P and SLIDE-P models.The TRIGRS-P and SLIDE-P models are used to generate the input samples and to calculate the values of FS.The outputs of several model runs with varied input parameters and rainfall forcings are analyzed statistically.A comparison suggests that there are significant differences in the simulations of the TRIGRS-P and SLIDE-P models.Although different precipitation data sets are used,the simulation results of TRIGRS-P are more concentrated.This study can inform the potential use of numerical models toforecast the spatial and temporal occurrence of regional rainfall-induced shallow landslides.展开更多
基金This work was supported by the Council of the Hong Kong Special Administrative Region, China (Grant No. HKU 7015/02E) the National Natural Science Foundation of China (Grant No. 40225004)Postdoctoral Science Foundation of China.
文摘Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in response to transient pore pressure by means of transient and unsaturated rainfall infiltration modeling. A case study is performed on the shallow landslide stability analysis in Hong Kong. Detailed analysis and discussion reached some useful conclusions on the tempo-spatial behavior and characteristics of slope stability response and pore pressure response to typical rainfall process. Comparison analysis is performed on some important issues including landslide stability response in different types of slopes with different hydraulic properties, antecedent rainfall and landslide stability, and the nature of pore pressure response time. These studies might give us an important insight into landslide tringgering mechanism and the hydrological process in response to rainfall, and provide systematic information and evidences for effective risk assessment and warning system establishment.
文摘Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4 grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.
基金This research is financially supported by the National Natural Science Foundation of China(Nos.41807274,41630640)the Sichuan Science and Technology Program(No.2019E0R2230230)the Scientific Foundation of the Chinese Academy of Sciences(No.KFJ-STS-QYZD-172)。
文摘Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide over the slip surface at different heights of the model slopes, as well as taking the whole slope to identify its deformation and failure processes. The results show that the rainfall duration corresponding to the initiation of the debris landslide and is exponentially related to rainfall intensity. Corresponding to the three intervals of the rainfall intensity, there are three types of slope failure modes:(1) the small-slump failure at the leading edge of the slope;(2) the block-slump failure but sometimes there are large blocks sliding down;and(3) the bulk failure but sometimes there is the block-slump failure. Based on the total rainfall-lasting time and the associated proportion of failed mass volume, the early warning of debris landslide can be classified into five grades, i.e., red, orange to red, orange, yellow to orange and yellow, which correspond to the five slope failure modes, respectively.
基金supported by the National Natural Science Foundation of China(Grant Nos.91437219&91637312)the Special Fund for Public Welfare Industry(Meteorology)administered by the Chinese Ministry of Finance and the Ministry of Science and Technology(Grant No.GYHY201406001)+2 种基金the China Postdoctoral Science Foundation(Grant No.2016M600695)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDY-SSWDQC018)the Special Program for Applied Research on Super Computation of the National Natural Science Foundation of China-Guangdong Joint Fund(The Second Phase)
文摘Based on analysis and simulation,the interaction of thermal forcing between the Tibetan Plateau(TP) and Iranian Plateau(IP) in summer is investigated.Associated influences on water vapor transport in the Asian subtropical monsoon region and the formation of a cold center in the lower stratosphere over Eurasia are also investigated.Results show that surface sensible heating(SH) over the two plateaus not only have mutual influences but also feedback to each other.SH over the IP can reduce the SH and increase the LH over the TP,whereas the SH over the TP can increase surface heating over the IP,thereby reaching quasi-equilibrium among the SH and LH over the TP,IP SH and atmosphere vertical motion.Therefore,the so-called Tibetan-Iranian Plateau coupling system(TIPS) is constructed,which influences atmosphere circulation.In the TIPS system,interaction between surface SH and LH over the TP plays a leading role.SH of the IP and TP influences on other regions not only have superimposed effects but also mutually offset.Accounting for contributions to the convergence of water vapor transport in the Asian subtropical monsoon region,TP SH contributes more than twice that of the IP.The combined influence of SH over TP and IP represents the major contribution to the convergence of water vapor transport in that region.In addition,the heating effect of TIPS increases the upper tropospheric temperature maximum and lifts the tropopause,cooling the lower stratosphere.Combined with large-scale thermal forcing of the Eurasian continent,the TIPS produces a strong anticyclonic circulation and the South Asian High that warms the upper troposphere and cools the lower stratosphere,thereby affecting regional and global weather and climate.
基金Supported by the National High Technology Research and Development Program of China ("863" Program) (Grant No.2007AA12Z216,2007AA120502)National Natural Science Foundation of China (Grant No.40701134)
文摘Most rainfall-induced landslide forecasting models focus on the relation between landslides and rainfall,which is one of the dynamic factors,and seldom consider the stacitc factors,such as geological and geograpical factors.Landslide susceptibility,however,is determinded by both static and dynamic factors.This article proposes a static and dynamic factors-coupled forecasting model(SDFCFM) of regional rainfall-induced landslides,which quantitatively considers both the static and dynamic factors that affect landslides.The generalized additive model(GAM) is applied to coupling both factors to get the landslide susceptibility.In the case study,SDFCFM is applied to forecast the landslide occurrences in Shenzhen during a rainfall process in 2008.Compared with the rainfall logistic regression model,the resulting landslide susceptibility map illustrates that SDFCFM can reduce the forecast redundancy and improve the hit ratio.It is both applicable and practical.The application of SDFCFM in landslide warning and prevention system will improve its efficiency and also cut down the cost of human and matreial resources.
基金supported by the National Natural Science Foundation of China (U2240221)the Sichuan Youth Science and Technology Innovation Research Team Project (2020JDTD0006)。
文摘Rainwater runoff that does not infiltrate the soil during heavy rainfall may increase slope instability. The effect of runoff is usually neglected in conventional rainfall-induced slope failure analysis to simplify the model. To analyze the effect of runoff on slope stability, this study simultaneously simulated the effects of surface runoff and rainfall infiltration on bank slopes in the Three Gorges Reservoir Area. A shallow slope failure method that can be used to analyze runoff was proposed based on the modified Green-Ampt model, the simplified Saint-Venant model, and the infinite slope model. In this model, the modified Green–Ampt model was used to estimate the rainfall infiltration capacity and the wetting front depth. The eight-flow(D8) method and the simplified Saint-Venant model were selected to estimate the distribution of runoff. By considering the wetting front depth as the slip surface depth, the factor of safety of the slope could be determined using the infinite slope stability model. A comparison of the different models reveals that runoff can escalate the instability of certain slopes, causing stable slopes to become unstable. Comparison of the unstable areas obtained from the simulation with the actual landslide sites shows that the model proposed in this study can successfully predict landslides at these sites. The slope instability assessment model proposed in this study offers an alternative approach for estimating high-risk areas in large mountainous regions.
基金This study was funded by the National Natural Science Foundation of China(Grant No.41972297)Talents in Hebei Provincial Education Office(Grant No.SLRC2019027)+1 种基金Natural Science Foundation of Hebei Province(Grant No.D2022202005)the Spanish national project EROSLOP(Grant No.PID2019-104266RB-I00/AEI/10.13039/501100011033).
文摘There is no doubt that land cover and climate changes have consequences on landslide activity,but it is still an open issue to assess and quantify their impacts.Wanzhou County in southwest China was selected as the test area to study rainfall-induced shallow landslide susceptibility under the future changes of land use and land cover(LULC)and climate.We used a high-resolution meteorological precipitation dataset and frequency distribution model to analyse the present extreme and antecedent rainfall conditions related to landslide activity.The future climate change factors were obtained from a 4-member multimodel ensemble that was derived from statistically downscaled regional climate simulations.The future LULC maps were simulated by the land change modeller(LCM)integrated into IDRISI Selva software.A total of six scenarios were defined by considering the rainfall(antecedent conditions and extreme events)and LULC changes towards two time periods(mid and late XXI century).A physically-based model was used to assess landslide susceptibility under these different scenarios.The results showed that the magnitude of both antecedent effective recharge and event rainfall in the region will evidently increase in the future.Under the scenario with a return period of 100 years,the antecedent rainfall in summer will increase by up to 63%whereas the event rainfall will increase by up to 54%for the late 21st century.The most considerable changes of LULC will be the increase of forest cover and the decrease of farming land.The magnitude of this change can reach+22.1%(forest)and–9.2%(farmland)from 2010 until 2100,respectively.We found that the negative impact of climate change on landslide susceptibility is greater than the stabilizing effect of LULC change,leading to an over decrease in stability over the study area.This is one of the first studies across Asia to assess and quantify changes of regional landslide susceptibility under scenarios driven by LULC and climate change.Our results aim to guide land use planning and cli
基金the Tertiary Education Fund(TETFUND),Nigeria,for funding this project。
文摘Landslide is a geological hazard typically associated with extreme events such as earthquakes,heavy rainfall,volcanic eruptions,changes in groundwater level,etc.This study was carried out in Okemesi-Ekiti(also known as Okemesi),Southwest Nigeria,with the purpose of using remote sensing and GIS technologies to analyze the environmental factors(grain size,direct shear strength resistance,rainfall data,wet density,surface,and slope)resulting in the occurrence of the Okemesi landslide.The study also aimed to conduct a vulnerability analysis in the study area to identify regions with a probability of landslide occurrence.The grain size analysis of the soil in the Okemesi landslide area showed that slope materials comprised 17.14%gravel,59.31%sand,and 19.48%fines,thus the soil type could be classified as poorly graded gravely sand with a high possibility of landslide occurrence.The geomorphic characteristics of the study area was characterized by slopes ranging from 0.00°to 49.00°,while most slopes in the area were less than 8.00°.The slope aspect direction was mainly in south(157.51°–202.50°),southwest(202.51°–247.50°),west(247.51°–292.50°),and north(0.00°–22.50°and 337.51°–360.00°).The highlands were primarily bounded by the slope directions of north(0.00°–22.50°and 337.51°–360.00°),northeast(22.51°–67.50°),east(67.51°–112.51°),and southeast(112.51°–157.50°),which indicated the potential direction of mass movement.The study area can be divided into three vulnerability zones:high,medium,and low,with the area percentages of 9.00%,61.80%,and 29.20%,respectively.The analysis suggested that the Okemesi landslide was likely triggered by rainfall,which might have weakened the physical structure of slope materials.Understanding the causes and impacts of landslides is crucial for policymakers to implement measures to mitigate landslide hazards,protect infrastructure,and prevent the loss of life in the landslide-prone regions.
文摘Landslides in the Himalayan region are primarily controlled by natural parameters,including rainfall,seismic activity,and anthropogenic parameters,such as the construction of large-scale projects like road development,tunneling and hydroelectric power projects and climate change.The parameters which are more crucial among these are a matter of scientific study and analysis.This research,taking Solan district,Himachal Pradesh,India,as the study area,aims to assess the impact of anthropogenic activities on landslide susceptibility at a regional scale.Landslide distribution was characterized into two groups,namely Rainfall-Induced Landslide(RIL)and Human-Induced Landslide(HIL)based on triggering factors.Multiple data such as slope angle,aspect,profile curvature,distance to drainage,distance to lineament,lithology,distance to road,normalized difference vegetation index(NDVI)and land use land cover(LULC)have been considered for delineating the landslide susceptibility zonation(LSZ)map.The effect of anthropogenic activities on landslide occurrences has been examined through the distribution of landslides along national highways and land use land cover changes(LULCC).Two sets of LSZ maps with a LULC of time interval covering five years(2017&2021)were prepared to compare the temporal progression of LULC and landslide susceptibility during the five years.The results indicated the significant impact of anthropogenic activities on the landslide susceptibility.LSZ map of the year 2021 shows that 23%area falls into high and very high susceptible classes and 48%area falls into very low and low susceptibility classes.Compared to LSZ map of 2017,high and very high susceptible classes have been increased by 15%,whereas very low and low susceptible classes have been reduced by 7%.The present case study will help to understand the potential driving parameters responsible for HIL and also suggest the inclusion of LULC in landslide susceptibility analysis.The study will demonstrate new opportunities for research that could help decis
文摘Various rainfall factors,which affect the activities of rainfall-induced debris flow,are discussed in this paper.The factors include antecedent precipitation,current precipitation,rainfall duration,intensity,peak,and rainfall pattern.Rainfall-induced debris flow is trigged by the co-action of current rainfall and antecedent rainfall.The advanced system of precipitation monitoring and forecasting in the rainfall-induced debris flow forecast system is established,which consists of four methods-numerical weather prediction,stationary meteorological satellite,weather radar echo and automatic weather station.Since the forecast of rainfall-induced debris flow is based on the prediction of precipitation,the prediction models objectively require more detailed and precise prediction products,which put forward a new research subject for meteorologists.
基金supported by the National Natural Science Funds of China (10932012)
文摘In this study, strength softening models are developed for exploring rainfall-induced landslide mechanism based on Mohr Coulomb strength theory with both saturation degree and temporal evolution into consideration. According to the ratio of two time scales available, the model can be classified into three categories, i.e., instant softening model, delay softening model, and coupling softening model. Corresponding evolution functions are specified to represent these kinds of softening processes and then applied to simulate landslide of homogeneous slopes triggered by rainfall, therefrom, useful conclusions can be drawn in the end.
基金support from the National Natural Science Foundation of China(U2005205)Science and Technology Innovation Platform Project of Fuzhou Science and Technology Bureau(No.2021-P-032)Opening Fund of Key Laboratory of Geohazard Prevention of Hilly Mountains,Ministry of Natural Resources(Fujian Key Laboratory of Geohazard Prevention)(FJKLGH2023K006).
文摘In order to investigate the spatial distribution of early warning threshold for landslide induced by rainfall in China,the literatures about rainfall thresholds of landslides in China in recent 20 years are selected.Statistical analysis and visualization methods were employed to systematically analyze the research progress of rainfall early warning thresholds at various scales.Taking the typical rainfall intensity-duration(I-D)threshold model as the research object,combined with the geographical characteristics of China and the average annual rainfall of 20 years,the spatial distribution of early warning thresholds for rainfall-induced landslide in China is depicted.The results show that the inspired rain intensity coefficientαof the rainfall threshold(I-D curve)in China roughly increases gradually with the decrease of topography.Moreover,under consistent annual rainfall conditions,the scalar indexβexhibits regular changes corresponding to variations in terrain.Topography and rainfall are the two main factors strongly associated with the rainfall threshold.This research establishes a clear framework for studying the early warning thresholds for rainfall-induced landslides in China and holds significant scientific implications for developing more effective rainfall threshold models.
基金supported by the National Key R&D Program of China(2019YFC1510700)the Sichuan Science and Technology Program(2023Y FS0380,2023YFS0377,2023NSFSC1989,2022YFS0539).
文摘In recent years,RS and GIS technologies have played an increasingly important role in various aspects of rainfall induced landslide research.In order to systematically understand their application situation,this paper extensively used various visualization analysis technologies for in-depth analysis of 1,161 documents collected by the WOS data platform in the past 27 years by combining quantitative and qualitative methods.Then,this article focuses on sub domain analysis from four aspects:landslide detection and monitoring,prediction models,sensitivity mapping,and risk assessment.The study found that the number of literature in thisfield has steadily increased and is expected to continue to rise.This literature review has attracted widespread attention from the academic community,but it challenging to meet research needs.Frequent and effective cooperationis between countries,institutions,and authors is very beneficial for promoting progress in thisfield.The future development direction is a new intelligent hybrid model that integrates multiple research methods.This study can provide researchers in thisfield with the core research force,hot topic evolution,and future development trends of future rainfall-induced landslides and contribute to landslide prevention and control decision-making and achieving the United Nations’sustainable development goals.
文摘Rainfall is one of the most important factors contributing to landslides, and gentle bedding incline, high-rainfall induced landslides are common throughout the world. Field observations and theoretical analyses have been used to assess slope instability caused by permeability variation. In this study, the influence of rainfall infiltration on gentle bedding incline slope behaviour was investigated using a centrifuge physical simulation test. The magnitude, pattern and development of pore water and earth pressure at the interface;the shear failure surface features;and the corresponding deformation and failure processes were considered. A model with interbedded sand and mud was created, and a centrifuge was used to simulate both natural and rainfall conditions. The weak intercalation was composed of single-material silty clay, and the landslide mass was composed of red-bed sandstone. A combination of photography, pore water pressure measurements and earth pressure measurements were used to examine the relationship between the pore water pressure, earth pressure and failure modes. When the slope experiences overall instability, the curves of the earth pressure and pore water pressure dramatically decrease. The results reveal that the failure shear surface largely depends on the differential creep caused by the properties of the rock mass and the rainfall infiltration.
基金supported by the Marie Curie Career Integration Grant(No.333177)the "100 Talents" programme of the Chinese Academy of Science+1 种基金the China Scholarship Councilthe Geo-Engineering Section of Delft University of Technology
文摘The simulation of slope failures,including both failure initiation and development,has been modelled using the material point method（MPM）.Numerical case studies involving various slope angles,heterogeneity and rainfall infiltration are presented.It is demonstrated that,by utilising a constitutive model which encompasses,in a simplified manner,both pre-and post-failure behaviour,the material point method is able to simulate commonly observed failure modes.This is a step towards being able to better quantify slope failure consequence and risk.
基金This study was funded by the National Key R&D Program of China(Grant No.2018YFC1506600)the Chinese Ministry of Science and Technology Project(No.2015CB452806)+1 种基金National Natural Science Foundation of China(No.41475044)the Basic Research Special Project of the Chinese Academy of Meteorological Sciences(No.2019Z008).There are no conflicts of interest to report.We gratefully acknowledge the anonymous reviewers for reviewing the manuscript and providing constructive comments and suggestions.
文摘Physical models used toforecast the temporal occurrence of rainfall-induced shallow landslides are based on deterministic laws.Owing to the existing measuring technology and our knowledge of the physical laws controlling landslide initiation,model uncertainties are due to an inability to accurately quantify the model input parameters and rainfall forcing data.An uncertainty analysis of slope instability prediction provides a rationale for refining the geotechnical models.The Transient Rainfall Infiltration and Grid-based Regional Slope Stability-Probabilistic(TRIGRS-P)model adopts a probabilistic approach to compute the changes in the Factor of Safety(FS)due to rainfall infiltration.Slope Infiltration Distributed Equilibrium(SLIDE)is a simplified physical model for landslide prediction.The new code(SLIDE-P)is also modified by adopting the same probabilistic approach to allow values of the SLIDE model input parameters to be sampled randomly.This study examines the relative importance of rainfall variability and the uncertainty in the other variables that determine slope stability.The precipitation data from weather stations,China Meteorological Administration Land Assimilation System 2.0(CLDAS2.0),China Meteorological Forcing Data set precipitation(CMFD),and China geological hazard bulletin are used to drive TRIGRS,SLIDE,TRIGRS-P and SLIDE-P models.The TRIGRS-P and SLIDE-P models are used to generate the input samples and to calculate the values of FS.The outputs of several model runs with varied input parameters and rainfall forcings are analyzed statistically.A comparison suggests that there are significant differences in the simulations of the TRIGRS-P and SLIDE-P models.Although different precipitation data sets are used,the simulation results of TRIGRS-P are more concentrated.This study can inform the potential use of numerical models toforecast the spatial and temporal occurrence of regional rainfall-induced shallow landslides.
