Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distri...Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distribution,and their associated effects on the ice accretion mechanism in the mountainous region of Southwest China.The maximum ice weight was positively correlated with the duration of ice accretion in the mountainous area.The duration of precipitation accounted for less than 20%of the icing period in the mountainous area,with solid-phase hydrometeors being predominant.Icing events,dominated by freezing rain(FR)and mixed rain–graupel(more than 70%),were characterized by glaze or highdensity mixed icing.The relationship between the melting energy and refreezing energy reflected the distribution characteristics of the proportion of FR under mixed-phase precipitation.The intensity of the warm layer and the dominant precipitation phase significantly affected the variations in the microphysical properties of FR.The melting of large dry snowflakes significantly contributed to FR in the mountainous areas,resulting in smaller generalized intercepts and larger mass-weighted mean diameters in the presence of a stronger warm layer.Under a weaker warm layer,the value of the massweighted mean diameter was significantly smaller because of the inability of large solid particles to melt.Finally,FR in the mountainous area dominated the ice weight during the rapid ice accumulation period.A numerical simulation of FR icing on wires effectively revealed the evolution of disaster-causing icing in mountainous areas.展开更多
Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy ch...Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy chimneys,castle koppies,pillars,weathered rock blocks,perched rocks,cavernous weathering features,grooves,and gnammas,formed on tuffs in semi-arid to semi-humid climatic conditions,as well as geoarchaeological remains belonging to various civilisations,primarily the Phrygians(including rock-cut tombs and settlements,fortresses,rock churches,façades,altars,and niches).This study aims at identifying these remarkable landforms that host cultural heritage and revealing the geoheritage value and geotourism potential of the region.The data obtained from the fieldwork were evaluated using the methodology proposed by Pereira and Pereira in 2010,and 26 geomorphosites were selected from 61 potential sites using this method.The analysis results revealed that although the region hosts numerous geomorphosites with high scientific,cultural,aesthetic,and ecological value,the overall levels of protection and touristic use of these landforms are generally low.Indeed,the area,which has the potential to be an important tourism region in the future,faces problems such as infrastructure deficiencies,transportation difficulties,lack of promotion,weaknesses in accommodation services,and destruction of geoheritage.These results highlight the importance of implementing sustainable geotourism strategies that are compatible with the region’s unique geoheritage.In this respect,this study is among the first to comprehensively inventory and assess the geomorphosites of Mountainous Phrygia,contributing to regional geoconservation and sustainable tourism development.展开更多
Cropland abandonment has been a widespread phenomenon in mountainous areas due to the increasing number of natural disasters and the massive migration of rural labor in the process of rapid urbanization.Land transfer ...Cropland abandonment has been a widespread phenomenon in mountainous areas due to the increasing number of natural disasters and the massive migration of rural labor in the process of rapid urbanization.Land transfer is a crucial prerequisite for ensuring food security and fostering rural revitalization.How to promote land transfer in mountainous areas remains a challenging but important task.Nevertheless,there is a dearth of research examining land transfers among farm households that specifically address mountainous regions,and the influence of grassroots governance and geographic location has not been thoroughly elucidated within this particular context.Based on 895household samples collected in Dabie Mountainous Area in China,this study employs binary and ordinal logistic regression models to provide a more comprehensive analysis on land transfers among rural households and the determinants,including the decision to transfer land,the existence of land transfer rents,the channel of land transfer,the duration of the transfer,the pre-transfer cultivation situation,and the level of satisfaction with the land transfer rent.The findings reveal that grassroots governance,geographic location,livelihood capital,and demographic factors significantly influence land transfers among rural households.Specifically,villagers'public participation positively affects land transfer participation(β=0.235,p<0.05),while the operation of village rules and regulations negatively impacts it(β=-0.296,p<0.05).Village cadre satisfaction positively influences both land transfer rent(β=0.274,p<0.05)and rent satisfaction(β=0.303,p<0.05).Improved civil relations in the village correlate with lower land transfer rent(β=-0.511,p<0.05),while a better social atmosphere is associated with higher satisfaction with transfer rent(β=0.575,p<0.01).Households at higher elevations tend to prefer government-mediated land transfers with longer durations.The distances to the township and county centers have contrasting effects on land transfer rent,but their impacts on participation in land transfer,choice of transfer channel,and duration are consistent.The study also found that different types of livelihood capital,as well as the demographic characteristics of households,significantly affect various aspects of land transfer.These empirical findings can inform policymaking to promote more efficient land transfers in mountainous region.展开更多
To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force...To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force distribution,deformation development,and crack propagation characteristics of a framed anti-sliding structure(FAS)under landslide thrust up to the point of failure.Results show that the maximum bending moment and its increase rate in the fore pile are greater than those in the rear pile,with the maximum bending moment of the fore pile approximately 1.1 times that of the rear pile.When the FAS fails,the displacement at the top of the fore pile is significantly greater,about 1.27 times that of the rear pile in the experiment.Major cracks develop at locations corresponding to the peak bending moments.Small transverse cracks initially appear on the upper surface at the intersection between the primary beam and rear pile and then spread to the side of the structure.At the failure stage,major cracks are observed at the pil-beam intersections and near the anchor points.Strengthening flexural stiffness at intersections where major cracks occur can improve the overall thrust-deformation coordination of the FAS,thereby maximizing its performance.展开更多
Free-space quantum key distribution(QKD)offers broader geographical coverage and more flexible system deployment than fiber-based systems.However,the free-space environment is highly complex,and various attenuation fa...Free-space quantum key distribution(QKD)offers broader geographical coverage and more flexible system deployment than fiber-based systems.However,the free-space environment is highly complex,and various attenuation factors can significantly reduce the key distribution efficiency or even lead to encoding failures.This paper discusses and analyzes the impact of turbulence and fog in mountainous environments on free-space discrete-variable quantum key distribution.Through numerical simulation,this study examines the effects of altitude and visibility on transmittance and turbulence intensity,finding that turbulence intensity decreases with increasing altitude while transmittance increases;improvements in visibility also lead to increased transmittance.Beam wandering due to turbulence is also dominant.Combining these factors,the effects on the total transmittance and the secret key rate are taken into consideration.Our work could provide a reference for the deployment of practical QKD systems in actual mountainous environments.展开更多
The study offers a conceptual framework illuminating sustainable rural development by a continuous cycling interplay among five interdependent systems,physical,social,economic,knowledge,and creative.The framework is a...The study offers a conceptual framework illuminating sustainable rural development by a continuous cycling interplay among five interdependent systems,physical,social,economic,knowledge,and creative.The framework is applied to analyze the livelihood transition in the economic system and conversion of traditional knowledge in the creative system for farm households engaged in large cardamom cultivation in Northern mountainous region in Vietnam.This study used a probit model to examine a data set comprising 300 households and confirmed that factors within the social and physical systems(such as labor,access to information,social networks,land use,and transportation infrastructure)determined livelihood transition to tourism employment within the economic system.In addition,the conversion of traditional knowledge in the creative system was found to be contingent upon non-farm employment and credit capital in the economic system,as well as traditional knowledge and knowledge exchange in the knowledge system.This study demonstrates how the sustainable development of rural agriculture can be achieved by converting traditional knowledge and transferring livelihood,contributing to attain Sustainable Development Goals 2(Zero Hunger)and SDG 12(Responsible Consumption and Production).展开更多
This paper first analyzes the fundamental characteristics and the advantages and disadvantages in the development and utilization of land resources in China s mountainous areas. It then explores the five major strateg...This paper first analyzes the fundamental characteristics and the advantages and disadvantages in the development and utilization of land resources in China s mountainous areas. It then explores the five major strategic tasks facing the sustainable development and utilization of mountainous land resources in China. From the perspective of human-land coordination and sustainable development, the paper proposes countermeasures and recommendations for the sustainable development and utilization of land resources in China s mountainous areas.展开更多
Focusing on comprehensive land consolidation in mountainous areas, this paper explores the connotation of comprehensive land consolidation and its internal logic for promoting rural revitalization. Furthermore, it elu...Focusing on comprehensive land consolidation in mountainous areas, this paper explores the connotation of comprehensive land consolidation and its internal logic for promoting rural revitalization. Furthermore, it elucidates the effectiveness and experience of mountainous area comprehensive land consolidation in the rural revitalization process by using practical cases. The aim is to provide theoretical reference and practical guidance for leveraging the role of comprehensive land consolidation in mountainous areas for rural revitalization, thereby promoting the sustainable utilization of land resources and the coordinated development of the economy and society in mountainous regions.展开更多
The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas an...The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas and brought challenges to development policies and revitalization strategies in mountainous rural regions,especially in karst mountainous areas.In light of the difficulty in and as the key to the development of China's mountainous rural areas,the scientific and systematic construction of indicators for evaluating the level of rural revitalization development and clarifying the level of rural revitalization development and influential factors in karst mountainous areas are of great significance to the implementation of the development of the strategy for the revitalization of the rural areas in karst mountainous areas in China.This study constructed an evaluation index system of the rural regional system and rural revitalization development(RTSRD)from the perspective of rural regional system theory,assessed the spatial differentiation patterns and influential factors of RTSRD,and refined a typical territorial model of rural revitalization development in karst mountainous areas by taking Guizhou Province,a typical karst mountainous region,as a case study area.The evaluation and spatial analyses show that the RTSRD indices of karst mountainous areas in the system perspective show a linear growth trend in all single dimensions,with industrial revitalization(IR)showing the most significant increase each year.In time,the RTSRD of karst mountainous regions has developed from low to high,with evident improvement;spatially,the RTSRD shows the characteristics of‘high in the middle and low in the surroundings,and low in the plateau and low in the depression,'with apparent spatial heterogeneity.In addition,this study found that the spatial and temporal differences in RTSRD result from a combination of endogenous push and exogenous pull in the rural system.In particular,this study has refined a typical regional model of rural revitalization development in karst mountainous regions,which provides theoretical support and case practice for rural development in other karst mountainous regions.At the same time,it provides a basis for decision-making for the county level government and rural development planning.展开更多
To reduce poverty and promote sustainable development in rural areas,it is crucial to explore the impact of labor mobility on the sustainable livelihoods in mountainous regions.Here,based on a questionnaire survey of ...To reduce poverty and promote sustainable development in rural areas,it is crucial to explore the impact of labor mobility on the sustainable livelihoods in mountainous regions.Here,based on a questionnaire survey of farmers and in-depth interview data in the area of the Qinling-Daba Mountains of China in 2021,we analyzed the characteristics of labor mobility,with livelihood capital as the entry point,discussed the impact of labor mobility on farmers’sustainable livelihood using propensity score matching(PSM).The res-ults showed that labor mobility was common in the Qinling-Daba Mountains area,with some form of labor mobility in 61.97%of households.The majority of households had only male mobility,and labor mobility tended to be small in scale,low in frequency,yet permanent and over long distances.Labor mobility had a significantly positive impact on farmers in mountainous regions,increasing the livelihood sustainability of rural households by 7.83%.However,the impact of labor mobility on different livelihood capital was differ-ent,which had the greatest improvement on financial capital,followed by social capital,although it weakened natural capital to some extent.Except for high-frequency mobility,the comprehensive impact of other types of labor mobility was positive.Among them,medi-um-scale mobility,seasonal mobility,inter-provincial mobility,and low-frequency mobility had more pronounced positive effects on farmers’sustainable livelihoods.Our study provided a reference to guide policy on rural migration,with the aim of providing support for the sustainable development of mountainous villages.展开更多
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es...At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures.展开更多
Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous areas.Certain simulation boundary conditions,such as the height and length of the computational domain or the c...Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous areas.Certain simulation boundary conditions,such as the height and length of the computational domain or the characteristics of inflow turbulence,can significantly impact the quality of predictions.In this study,we examined these boundary conditions within the context of the mountainous terrain around a long-span cable-stayed bridge using a wind tunnel experiment.Various sizes of computational domains and turbulent incoming wind velocities were used in large eddy simulations.The results show that when the height of the computational domain is five times greater than the height of the terrain model,there is minimal influence from the top wall on the wind field characteristics in this complex mountainous area.Expanding the length of the wake region of the computational domain has negligible effects on the wind fields.Turbulence in the inlet boundary reduces the length of the wake region on a leeward hill with a low slope,but has less impact on the mean wind velocity of steep hills.展开更多
This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental information.Firstly,using th...This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental information.Firstly,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV groups.Secondly,the task region is decomposed into several high-value sub-regions by using data clustering method.Based on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search efficiency.Third,the Elite Dung Beetle Optimization Algorithm(EDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be avoided.Finally,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path length.The effectiveness and superiority of the proposed schemes are verified by the simulation.展开更多
Critical zone(CZ)plays a vital role in sustaining biodiversity and humanity.However,flux quantification within CZ,particularly in terms of subsurface hydrological partitioning,remains a significant challenge.This stud...Critical zone(CZ)plays a vital role in sustaining biodiversity and humanity.However,flux quantification within CZ,particularly in terms of subsurface hydrological partitioning,remains a significant challenge.This study focused on quantifying subsurface hydrological partitioning,specifically in an alpine mountainous area,and highlighted the important role of lateral flow during this process.Precipitation was usually classified as two parts into the soil:increased soil water content(SWC)and lateral flow out of the soil pit.It was found that 65%–88%precipitation contributed to lateral flow.The second common partitioning class showed an increase in SWC caused by both precipitation and lateral flow into the soil pit.In this case,lateral flow contributed to the SWC increase ranging from 43%to 74%,which was notably larger than the SWC increase caused by precipitation.On alpine meadows,lateral flow from the soil pit occurred when the shallow soil was wetter than the field capacity.This result highlighted the need for three-dimensional simulation between soil layers in Earth system models(ESMs).During evapotranspiration process,significant differences were observed in the classification of subsurface hydrological partitioning among different vegetation types.Due to tangled and aggregated fine roots in the surface soil on alpine meadows,the majority of subsurface responses involved lateral flow,which provided 98%–100%of evapotranspiration(ET).On grassland,there was a high probability(0.87),which ET was entirely provided by lateral flow.The main reason for underestimating transpiration through soil water dynamics in previous research was the neglect of lateral root water uptake.Furthermore,there was a probability of 0.12,which ET was entirely provided by SWC decrease on grassland.In this case,there was a high probability(0.98)that soil water responses only occurred at layer 2(10–20 cm),because grass roots mainly distributed in this soil layer,and grasses often used their deep roots for water uptake during ET.To improve the estimation of soil water dynamics and ET,we established a random forest(RF)model to simulate lateral flow and then corrected the community land model(CLM).RF model demonstrated good performance and led to significant improvements in CLM simulation.These findings enhance our understanding of subsurface hydrological partitioning and emphasize the importance of considering lateral flow in ESMs and hydrological research.展开更多
This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade sett...This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade settlement control standard that states that the maximum differential settlement value should be less than 5 cm when the embankment fill height exceeds 20 m.Similarly,the maximum differential settlement value should be less than 10 cm when the embankment fill height does not exceed 20 m.The findings of the study can provide a useful reference for the design of roadbed widening in highway reconstruction and expansion projects.展开更多
Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological env...Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and bays.In order to investigate the seasonal characteristics of nutrients in small mountainous rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountainous rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved inorganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry season.The concentrations of dissolved inorganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),respectively.Influenced by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle reaches.Two rainstorms during the Meiyu period in the watershed caused the pulse runoff in the river.The maximum daily runoff reached 70 times that before rains.The maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,respectively.In view that the watershed experienced several rainstorms in the wet season,the river,with pulse runoff,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea.展开更多
The leakage gas from a buried natural gas pipelines has the great potential to cause economic losses and environmental pollution owing to the complexity of the mountainous environment.In this study,computational fluid...The leakage gas from a buried natural gas pipelines has the great potential to cause economic losses and environmental pollution owing to the complexity of the mountainous environment.In this study,computational fluid dynamics(CFD)method was applied to investigate the diffusion law and hazard range of buried natural gas pipeline leakage in mountainous environment.Based on cloud chart,concentration at the monitoring site and hazard range of lower explosion limit(LEL)and upper explosion limit(UEL),the influences of leakage hole direction and shape,soil property,burial depth,obstacle type on the diffusion law and hazard range are analyzed.Results show that the leakage gas is not radially diffused until it reaches the ground,and the velocity of gas diffusion to the ground and the hazard range decrease as the angle between the leaking direction and the buoyancy direction increases.Triangular and square leak holes have a faster diffusion rate and a wider hazard range than circular.The diffusion rate of leakage gas in soil rises as soil granularity and porosity increase.The time of leakage gas diffusion to the ground increases significantly with the increase of burial depth,and the hazard range reduces as burial depth increases.Boulder-type obstacles will alter the diffusion path of the leakage gas and accelerate the expansion of the hazard distance,while trench-type obstacles will cause the natural gas to accumulate in the trench and form a high concentration region slowing the expansion of the surface gas concentration.展开更多
Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodolog...Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodology/approach–With the continuous promotion of infrastructure construction,the focus of China’s railway construction has gradually shifted to the western region.The four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of China have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of China through on-site research.The impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of China was proposed.Findings–The daily temperature difference in the western mountainous areas of China is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless tracks.It will result in cracking.The wind speed in the western plateau region is about 2.5 to 3 times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain region.The drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability problems.The environmental temperature in the western mountainous areas of China is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway concrete.The environmental air pressure in the western plateau region is only 60%of that in the plain region.The moisture inside the concrete is more likely to diffuse into the surrounding environment under the pressure difference,resulting in greater water loss and shrinkage deformation of the concrete in the plateau region.The above four issues will collectively lead to the rapid deterioration of concrete durability in the western plateau region.The corresponding durability improvement suggestions from theoretical research,new technology development and standard system was proposed in this paper.Originality/value–The research can provide the mechanism of durability degradation of railway concrete in the western mountainous areas of China and corresponding improvement strategies.展开更多
[Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore ...[Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore the characteristics of ecological risk evolution under different landscape patterns in the region,with a view to providing reference for land classification protection,sustainable use of resources and regional ecological risk optimization in karst mountainous areas.[Method]Taking Huangping County,a typical karst mountainous area,as an example,eight evaluation factors of natural and landscape patterns were selected to construct a landscape ecological risk evaluation model,to quantitatively explore the spatio-temporal evolution of landscape ecological risk and the trend of risk level transfer in the study area from^(2)010-2018,and to reveal the complex relationship between ecological risk and topography in karst mountainous areas.[Result]①From 2010 to 2018,land use types changed to different degrees,with the most amount of woodland transferred out(1627.37 hm^(2))and the most amount of construction land transferred in(1303.93 hm^(2));a total of 3552.31 hm^(2) of land was transferred,with a change ratio of 2.13%,and there was a significant conversion between construction land,arable land,and woodland.②From 2010 to 2018,the landscape ecological risk in the study area changed significantly,and the landscape ecological risk index decreased from 0.3441 to 0.1733,showing an upward and then downward trend;the landscape ecological risk of the whole region was dominated by low-risk and lower-risk zones,and the ecological risk level generally shifted from a high level to a low level,and the ecological environment was improved.③There was a negative correlation between ecological risk and topographic position,and high-risk zones were mainly distributed among low topographic zones;with the change of time,the advantage of risk level for the selection of topography was gradually weakened,and the influence of anthropogenic factors on the ecological risk of the landscape was becoming more and more prominent.[Conclusion]This paper can provide theoretical basis for land use optimization and ecological protection in karst mountainous areas.展开更多
Natural and human-made disasters are threatening cities around the world.The resilience of cities plays a critical role in disaster risk response and post-disaster recovery.In mountainous cities,landslides are among t...Natural and human-made disasters are threatening cities around the world.The resilience of cities plays a critical role in disaster risk response and post-disaster recovery.In mountainous cities,landslides are among the most frequent and destructive hazards.This study presents a novel methodological framework for assessing the spatial resilience of mountainous cities specifically against landslides.Focusing on Chongqing in the Three Gorges Reservoir region,this study conceptually divides the disaster resilience of mountain cities to landslides into two dimensions:environmental resilience and social resilience.This study developed a comprehensive database by compiling data from 4,464 historical landslide events,incorporating 17 environmental resilience indicators and 16 social resilience indicators.Random forest(RF)model was employed to evaluate environmental resilience,achieving a high AUC of 0.968 and an accuracy of 97.1%.Social resilience was assessed by the Analytic Hierarchy Process(AHP),and comprehensive resilience was ranked by the Technique for Order of Preference by Similarity to Ideal Solution(TOPSIS).Key findings include:(1)Establishing a multi-dimensional resilience indicator system that effectively assesses landslide-oriented resilience in mountainous cities.(2)Comprehensive resilience in mountainous cities exhibit distinct spatial clustering patterns.Regions with lower environmental resilience are mainly characterized by high rainfall and complex terrain.higher social resilience concentrated in city centers,while peripheral regions face challenges due to weaker economies and inadequate healthcare infrastructure.(3)In the future development of mountain cities,comprehensive and sustainable strategies should be adopted to balance the relationship between environmental resilience and social resilience.This study provides a robust framework for disaster prevention and resilience assessment in mountainous cities,which can be applied to evaluate the disaster resistance capabilities of other mountainous cities.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.42325503)the Hubei Provincial Natural Science Foundation and the Meteorological Innovation and Development Project of China(Grant Nos.2023AFD096 and 2022CFD122)+1 种基金the Natural Science Foundation of Wuhan(Grant No.2024020901030454)the Beijige Foundation of NJIAS(Grant No.BJG202304)。
文摘Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distribution,and their associated effects on the ice accretion mechanism in the mountainous region of Southwest China.The maximum ice weight was positively correlated with the duration of ice accretion in the mountainous area.The duration of precipitation accounted for less than 20%of the icing period in the mountainous area,with solid-phase hydrometeors being predominant.Icing events,dominated by freezing rain(FR)and mixed rain–graupel(more than 70%),were characterized by glaze or highdensity mixed icing.The relationship between the melting energy and refreezing energy reflected the distribution characteristics of the proportion of FR under mixed-phase precipitation.The intensity of the warm layer and the dominant precipitation phase significantly affected the variations in the microphysical properties of FR.The melting of large dry snowflakes significantly contributed to FR in the mountainous areas,resulting in smaller generalized intercepts and larger mass-weighted mean diameters in the presence of a stronger warm layer.Under a weaker warm layer,the value of the massweighted mean diameter was significantly smaller because of the inability of large solid particles to melt.Finally,FR in the mountainous area dominated the ice weight during the rapid ice accumulation period.A numerical simulation of FR icing on wires effectively revealed the evolution of disaster-causing icing in mountainous areas.
文摘Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy chimneys,castle koppies,pillars,weathered rock blocks,perched rocks,cavernous weathering features,grooves,and gnammas,formed on tuffs in semi-arid to semi-humid climatic conditions,as well as geoarchaeological remains belonging to various civilisations,primarily the Phrygians(including rock-cut tombs and settlements,fortresses,rock churches,façades,altars,and niches).This study aims at identifying these remarkable landforms that host cultural heritage and revealing the geoheritage value and geotourism potential of the region.The data obtained from the fieldwork were evaluated using the methodology proposed by Pereira and Pereira in 2010,and 26 geomorphosites were selected from 61 potential sites using this method.The analysis results revealed that although the region hosts numerous geomorphosites with high scientific,cultural,aesthetic,and ecological value,the overall levels of protection and touristic use of these landforms are generally low.Indeed,the area,which has the potential to be an important tourism region in the future,faces problems such as infrastructure deficiencies,transportation difficulties,lack of promotion,weaknesses in accommodation services,and destruction of geoheritage.These results highlight the importance of implementing sustainable geotourism strategies that are compatible with the region’s unique geoheritage.In this respect,this study is among the first to comprehensively inventory and assess the geomorphosites of Mountainous Phrygia,contributing to regional geoconservation and sustainable tourism development.
基金supported by the National Natural Science Foundation of China(Grant Nos.42371315,41901213)the Humanities and Social Sciences General Research Program of the Ministry of Education(Grant No.23YJC790141)。
文摘Cropland abandonment has been a widespread phenomenon in mountainous areas due to the increasing number of natural disasters and the massive migration of rural labor in the process of rapid urbanization.Land transfer is a crucial prerequisite for ensuring food security and fostering rural revitalization.How to promote land transfer in mountainous areas remains a challenging but important task.Nevertheless,there is a dearth of research examining land transfers among farm households that specifically address mountainous regions,and the influence of grassroots governance and geographic location has not been thoroughly elucidated within this particular context.Based on 895household samples collected in Dabie Mountainous Area in China,this study employs binary and ordinal logistic regression models to provide a more comprehensive analysis on land transfers among rural households and the determinants,including the decision to transfer land,the existence of land transfer rents,the channel of land transfer,the duration of the transfer,the pre-transfer cultivation situation,and the level of satisfaction with the land transfer rent.The findings reveal that grassroots governance,geographic location,livelihood capital,and demographic factors significantly influence land transfers among rural households.Specifically,villagers'public participation positively affects land transfer participation(β=0.235,p<0.05),while the operation of village rules and regulations negatively impacts it(β=-0.296,p<0.05).Village cadre satisfaction positively influences both land transfer rent(β=0.274,p<0.05)and rent satisfaction(β=0.303,p<0.05).Improved civil relations in the village correlate with lower land transfer rent(β=-0.511,p<0.05),while a better social atmosphere is associated with higher satisfaction with transfer rent(β=0.575,p<0.01).Households at higher elevations tend to prefer government-mediated land transfers with longer durations.The distances to the township and county centers have contrasting effects on land transfer rent,but their impacts on participation in land transfer,choice of transfer channel,and duration are consistent.The study also found that different types of livelihood capital,as well as the demographic characteristics of households,significantly affect various aspects of land transfer.These empirical findings can inform policymaking to promote more efficient land transfers in mountainous region.
基金The National Natural Science Foundation of China(No.52078427).
文摘To ensure the operational safety of railways in the landslide-prone areas of mountainous regions,a large-scale model test and numerical simulation were conducted to study the bending moment distribution,internal force distribution,deformation development,and crack propagation characteristics of a framed anti-sliding structure(FAS)under landslide thrust up to the point of failure.Results show that the maximum bending moment and its increase rate in the fore pile are greater than those in the rear pile,with the maximum bending moment of the fore pile approximately 1.1 times that of the rear pile.When the FAS fails,the displacement at the top of the fore pile is significantly greater,about 1.27 times that of the rear pile in the experiment.Major cracks develop at locations corresponding to the peak bending moments.Small transverse cracks initially appear on the upper surface at the intersection between the primary beam and rear pile and then spread to the side of the structure.At the failure stage,major cracks are observed at the pil-beam intersections and near the anchor points.Strengthening flexural stiffness at intersections where major cracks occur can improve the overall thrust-deformation coordination of the FAS,thereby maximizing its performance.
文摘Free-space quantum key distribution(QKD)offers broader geographical coverage and more flexible system deployment than fiber-based systems.However,the free-space environment is highly complex,and various attenuation factors can significantly reduce the key distribution efficiency or even lead to encoding failures.This paper discusses and analyzes the impact of turbulence and fog in mountainous environments on free-space discrete-variable quantum key distribution.Through numerical simulation,this study examines the effects of altitude and visibility on transmittance and turbulence intensity,finding that turbulence intensity decreases with increasing altitude while transmittance increases;improvements in visibility also lead to increased transmittance.Beam wandering due to turbulence is also dominant.Combining these factors,the effects on the total transmittance and the secret key rate are taken into consideration.Our work could provide a reference for the deployment of practical QKD systems in actual mountainous environments.
文摘The study offers a conceptual framework illuminating sustainable rural development by a continuous cycling interplay among five interdependent systems,physical,social,economic,knowledge,and creative.The framework is applied to analyze the livelihood transition in the economic system and conversion of traditional knowledge in the creative system for farm households engaged in large cardamom cultivation in Northern mountainous region in Vietnam.This study used a probit model to examine a data set comprising 300 households and confirmed that factors within the social and physical systems(such as labor,access to information,social networks,land use,and transportation infrastructure)determined livelihood transition to tourism employment within the economic system.In addition,the conversion of traditional knowledge in the creative system was found to be contingent upon non-farm employment and credit capital in the economic system,as well as traditional knowledge and knowledge exchange in the knowledge system.This study demonstrates how the sustainable development of rural agriculture can be achieved by converting traditional knowledge and transferring livelihood,contributing to attain Sustainable Development Goals 2(Zero Hunger)and SDG 12(Responsible Consumption and Production).
文摘This paper first analyzes the fundamental characteristics and the advantages and disadvantages in the development and utilization of land resources in China s mountainous areas. It then explores the five major strategic tasks facing the sustainable development and utilization of mountainous land resources in China. From the perspective of human-land coordination and sustainable development, the paper proposes countermeasures and recommendations for the sustainable development and utilization of land resources in China s mountainous areas.
文摘Focusing on comprehensive land consolidation in mountainous areas, this paper explores the connotation of comprehensive land consolidation and its internal logic for promoting rural revitalization. Furthermore, it elucidates the effectiveness and experience of mountainous area comprehensive land consolidation in the rural revitalization process by using practical cases. The aim is to provide theoretical reference and practical guidance for leveraging the role of comprehensive land consolidation in mountainous areas for rural revitalization, thereby promoting the sustainable utilization of land resources and the coordinated development of the economy and society in mountainous regions.
基金supported by the National Natural Science Foundation of China(Grant No.42061035)the Guizhou Provincial Program on Commercialization of Scientific and Technological Achievements([2022]010)。
文摘The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas and brought challenges to development policies and revitalization strategies in mountainous rural regions,especially in karst mountainous areas.In light of the difficulty in and as the key to the development of China's mountainous rural areas,the scientific and systematic construction of indicators for evaluating the level of rural revitalization development and clarifying the level of rural revitalization development and influential factors in karst mountainous areas are of great significance to the implementation of the development of the strategy for the revitalization of the rural areas in karst mountainous areas in China.This study constructed an evaluation index system of the rural regional system and rural revitalization development(RTSRD)from the perspective of rural regional system theory,assessed the spatial differentiation patterns and influential factors of RTSRD,and refined a typical territorial model of rural revitalization development in karst mountainous areas by taking Guizhou Province,a typical karst mountainous region,as a case study area.The evaluation and spatial analyses show that the RTSRD indices of karst mountainous areas in the system perspective show a linear growth trend in all single dimensions,with industrial revitalization(IR)showing the most significant increase each year.In time,the RTSRD of karst mountainous regions has developed from low to high,with evident improvement;spatially,the RTSRD shows the characteristics of‘high in the middle and low in the surroundings,and low in the plateau and low in the depression,'with apparent spatial heterogeneity.In addition,this study found that the spatial and temporal differences in RTSRD result from a combination of endogenous push and exogenous pull in the rural system.In particular,this study has refined a typical regional model of rural revitalization development in karst mountainous regions,which provides theoretical support and case practice for rural development in other karst mountainous regions.At the same time,it provides a basis for decision-making for the county level government and rural development planning.
基金Under the auspices of National Natural Science Foundation of China(No.42371313,41971268)。
文摘To reduce poverty and promote sustainable development in rural areas,it is crucial to explore the impact of labor mobility on the sustainable livelihoods in mountainous regions.Here,based on a questionnaire survey of farmers and in-depth interview data in the area of the Qinling-Daba Mountains of China in 2021,we analyzed the characteristics of labor mobility,with livelihood capital as the entry point,discussed the impact of labor mobility on farmers’sustainable livelihood using propensity score matching(PSM).The res-ults showed that labor mobility was common in the Qinling-Daba Mountains area,with some form of labor mobility in 61.97%of households.The majority of households had only male mobility,and labor mobility tended to be small in scale,low in frequency,yet permanent and over long distances.Labor mobility had a significantly positive impact on farmers in mountainous regions,increasing the livelihood sustainability of rural households by 7.83%.However,the impact of labor mobility on different livelihood capital was differ-ent,which had the greatest improvement on financial capital,followed by social capital,although it weakened natural capital to some extent.Except for high-frequency mobility,the comprehensive impact of other types of labor mobility was positive.Among them,medi-um-scale mobility,seasonal mobility,inter-provincial mobility,and low-frequency mobility had more pronounced positive effects on farmers’sustainable livelihoods.Our study provided a reference to guide policy on rural migration,with the aim of providing support for the sustainable development of mountainous villages.
基金National Natural Science Fund of China under Nos.52168072 and 51808467High-level Talents Support Plan of Yunnan Province of China(2020)。
文摘At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures.
基金supported by the National Natural Science Foundation of China(Nos.51925808 and 52178516)the Natural Science Foundation of Hunan Province(Nos.2020JJ5745 and 2023JJ20073),China.
文摘Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous areas.Certain simulation boundary conditions,such as the height and length of the computational domain or the characteristics of inflow turbulence,can significantly impact the quality of predictions.In this study,we examined these boundary conditions within the context of the mountainous terrain around a long-span cable-stayed bridge using a wind tunnel experiment.Various sizes of computational domains and turbulent incoming wind velocities were used in large eddy simulations.The results show that when the height of the computational domain is five times greater than the height of the terrain model,there is minimal influence from the top wall on the wind field characteristics in this complex mountainous area.Expanding the length of the wake region of the computational domain has negligible effects on the wind fields.Turbulence in the inlet boundary reduces the length of the wake region on a leeward hill with a low slope,but has less impact on the mean wind velocity of steep hills.
基金supported by the Natural Science Foundation of China(62273068)the Fundamental Research Funds for the Central Universities(3132023512)Dalian Science and Technology Innovation Fund(2019J12GX040).
文摘This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental information.Firstly,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV groups.Secondly,the task region is decomposed into several high-value sub-regions by using data clustering method.Based on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search efficiency.Third,the Elite Dung Beetle Optimization Algorithm(EDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be avoided.Finally,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path length.The effectiveness and superiority of the proposed schemes are verified by the simulation.
基金funded by the National Natural Science Foundation of China(42371022,42030501,41877148).
文摘Critical zone(CZ)plays a vital role in sustaining biodiversity and humanity.However,flux quantification within CZ,particularly in terms of subsurface hydrological partitioning,remains a significant challenge.This study focused on quantifying subsurface hydrological partitioning,specifically in an alpine mountainous area,and highlighted the important role of lateral flow during this process.Precipitation was usually classified as two parts into the soil:increased soil water content(SWC)and lateral flow out of the soil pit.It was found that 65%–88%precipitation contributed to lateral flow.The second common partitioning class showed an increase in SWC caused by both precipitation and lateral flow into the soil pit.In this case,lateral flow contributed to the SWC increase ranging from 43%to 74%,which was notably larger than the SWC increase caused by precipitation.On alpine meadows,lateral flow from the soil pit occurred when the shallow soil was wetter than the field capacity.This result highlighted the need for three-dimensional simulation between soil layers in Earth system models(ESMs).During evapotranspiration process,significant differences were observed in the classification of subsurface hydrological partitioning among different vegetation types.Due to tangled and aggregated fine roots in the surface soil on alpine meadows,the majority of subsurface responses involved lateral flow,which provided 98%–100%of evapotranspiration(ET).On grassland,there was a high probability(0.87),which ET was entirely provided by lateral flow.The main reason for underestimating transpiration through soil water dynamics in previous research was the neglect of lateral root water uptake.Furthermore,there was a probability of 0.12,which ET was entirely provided by SWC decrease on grassland.In this case,there was a high probability(0.98)that soil water responses only occurred at layer 2(10–20 cm),because grass roots mainly distributed in this soil layer,and grasses often used their deep roots for water uptake during ET.To improve the estimation of soil water dynamics and ET,we established a random forest(RF)model to simulate lateral flow and then corrected the community land model(CLM).RF model demonstrated good performance and led to significant improvements in CLM simulation.These findings enhance our understanding of subsurface hydrological partitioning and emphasize the importance of considering lateral flow in ESMs and hydrological research.
文摘This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade settlement control standard that states that the maximum differential settlement value should be less than 5 cm when the embankment fill height exceeds 20 m.Similarly,the maximum differential settlement value should be less than 10 cm when the embankment fill height does not exceed 20 m.The findings of the study can provide a useful reference for the design of roadbed widening in highway reconstruction and expansion projects.
基金financially supported by the Postdoctoral Foundation of Qingdao(Pb Isotopes of Oujiang River to Quantitatively Identify Sediment Provenance in Oujiang Estuary and Adjacent Area)the China Geological Survey Project(No.DD20190276)the Fund of Ministry of Science and Technology(Nos.2013FY112200 and 2019YFE0127200).
文摘Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and bays.In order to investigate the seasonal characteristics of nutrients in small mountainous rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountainous rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved inorganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry season.The concentrations of dissolved inorganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),respectively.Influenced by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle reaches.Two rainstorms during the Meiyu period in the watershed caused the pulse runoff in the river.The maximum daily runoff reached 70 times that before rains.The maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,respectively.In view that the watershed experienced several rainstorms in the wet season,the river,with pulse runoff,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea.
文摘The leakage gas from a buried natural gas pipelines has the great potential to cause economic losses and environmental pollution owing to the complexity of the mountainous environment.In this study,computational fluid dynamics(CFD)method was applied to investigate the diffusion law and hazard range of buried natural gas pipeline leakage in mountainous environment.Based on cloud chart,concentration at the monitoring site and hazard range of lower explosion limit(LEL)and upper explosion limit(UEL),the influences of leakage hole direction and shape,soil property,burial depth,obstacle type on the diffusion law and hazard range are analyzed.Results show that the leakage gas is not radially diffused until it reaches the ground,and the velocity of gas diffusion to the ground and the hazard range decrease as the angle between the leaking direction and the buoyancy direction increases.Triangular and square leak holes have a faster diffusion rate and a wider hazard range than circular.The diffusion rate of leakage gas in soil rises as soil granularity and porosity increase.The time of leakage gas diffusion to the ground increases significantly with the increase of burial depth,and the hazard range reduces as burial depth increases.Boulder-type obstacles will alter the diffusion path of the leakage gas and accelerate the expansion of the hazard distance,while trench-type obstacles will cause the natural gas to accumulate in the trench and form a high concentration region slowing the expansion of the surface gas concentration.
基金the National Science Foundation of China(52478289)National Key Research and Development Program of China(2020YFC1909900)Scientific Research Project of China Academy of Railway Sciences Group Co.,Ltd(2023YJ184).
文摘Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodology/approach–With the continuous promotion of infrastructure construction,the focus of China’s railway construction has gradually shifted to the western region.The four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of China have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of China through on-site research.The impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of China was proposed.Findings–The daily temperature difference in the western mountainous areas of China is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless tracks.It will result in cracking.The wind speed in the western plateau region is about 2.5 to 3 times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain region.The drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability problems.The environmental temperature in the western mountainous areas of China is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway concrete.The environmental air pressure in the western plateau region is only 60%of that in the plain region.The moisture inside the concrete is more likely to diffuse into the surrounding environment under the pressure difference,resulting in greater water loss and shrinkage deformation of the concrete in the plateau region.The above four issues will collectively lead to the rapid deterioration of concrete durability in the western plateau region.The corresponding durability improvement suggestions from theoretical research,new technology development and standard system was proposed in this paper.Originality/value–The research can provide the mechanism of durability degradation of railway concrete in the western mountainous areas of China and corresponding improvement strategies.
基金the National Natural Science Foundation of China(41661088)Project for Guizhou Province"High-level Innovative Talent Training Program‘Hundred’Level Talents"(QKHPTRC[2016]5674)Guizhou Science and Technology Plan Project(QKHZC[2023]GENERAL211).
文摘[Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore the characteristics of ecological risk evolution under different landscape patterns in the region,with a view to providing reference for land classification protection,sustainable use of resources and regional ecological risk optimization in karst mountainous areas.[Method]Taking Huangping County,a typical karst mountainous area,as an example,eight evaluation factors of natural and landscape patterns were selected to construct a landscape ecological risk evaluation model,to quantitatively explore the spatio-temporal evolution of landscape ecological risk and the trend of risk level transfer in the study area from^(2)010-2018,and to reveal the complex relationship between ecological risk and topography in karst mountainous areas.[Result]①From 2010 to 2018,land use types changed to different degrees,with the most amount of woodland transferred out(1627.37 hm^(2))and the most amount of construction land transferred in(1303.93 hm^(2));a total of 3552.31 hm^(2) of land was transferred,with a change ratio of 2.13%,and there was a significant conversion between construction land,arable land,and woodland.②From 2010 to 2018,the landscape ecological risk in the study area changed significantly,and the landscape ecological risk index decreased from 0.3441 to 0.1733,showing an upward and then downward trend;the landscape ecological risk of the whole region was dominated by low-risk and lower-risk zones,and the ecological risk level generally shifted from a high level to a low level,and the ecological environment was improved.③There was a negative correlation between ecological risk and topographic position,and high-risk zones were mainly distributed among low topographic zones;with the change of time,the advantage of risk level for the selection of topography was gradually weakened,and the influence of anthropogenic factors on the ecological risk of the landscape was becoming more and more prominent.[Conclusion]This paper can provide theoretical basis for land use optimization and ecological protection in karst mountainous areas.
基金funding for this research was provided by the National Key Research and Development Program of China(Grant No.2023YFC3007204).
文摘Natural and human-made disasters are threatening cities around the world.The resilience of cities plays a critical role in disaster risk response and post-disaster recovery.In mountainous cities,landslides are among the most frequent and destructive hazards.This study presents a novel methodological framework for assessing the spatial resilience of mountainous cities specifically against landslides.Focusing on Chongqing in the Three Gorges Reservoir region,this study conceptually divides the disaster resilience of mountain cities to landslides into two dimensions:environmental resilience and social resilience.This study developed a comprehensive database by compiling data from 4,464 historical landslide events,incorporating 17 environmental resilience indicators and 16 social resilience indicators.Random forest(RF)model was employed to evaluate environmental resilience,achieving a high AUC of 0.968 and an accuracy of 97.1%.Social resilience was assessed by the Analytic Hierarchy Process(AHP),and comprehensive resilience was ranked by the Technique for Order of Preference by Similarity to Ideal Solution(TOPSIS).Key findings include:(1)Establishing a multi-dimensional resilience indicator system that effectively assesses landslide-oriented resilience in mountainous cities.(2)Comprehensive resilience in mountainous cities exhibit distinct spatial clustering patterns.Regions with lower environmental resilience are mainly characterized by high rainfall and complex terrain.higher social resilience concentrated in city centers,while peripheral regions face challenges due to weaker economies and inadequate healthcare infrastructure.(3)In the future development of mountain cities,comprehensive and sustainable strategies should be adopted to balance the relationship between environmental resilience and social resilience.This study provides a robust framework for disaster prevention and resilience assessment in mountainous cities,which can be applied to evaluate the disaster resistance capabilities of other mountainous cities.
