The evaluation of consolidated cultivated land quality can provide basic information for how to perfect the program of land consolidation,as well as a reference for the dynamic monitoring of farmland quality in mining...The evaluation of consolidated cultivated land quality can provide basic information for how to perfect the program of land consolidation,as well as a reference for the dynamic monitoring of farmland quality in mining area. Based on the consultation and analysis of related literature,we can conclude that: firstly,most scholars focus on soil consolidation,while consider little about land use and economic condition. Secondly,foreign scholars usually use crop yields to judge the success of land consolidation,while domestic scholars have been evaluated the quality of consolidated cultivated land synthetically from several aspects,such as soil fertility,soil environmental quality,and farmland infrastructure conditions. Specifically,most of the evaluations are static,and indicators are different. Besides,the quality of consolidated cultivated land is generally low,and it lacks systematic research on technologies for improving quality of cultivated land consolidated from coal mining subsided land. It is concluded that future researches should focus on establishing scientific and feasible evaluation system to realize comparison of quality change in the dynamic course of " undisturbed-subsided-consolidated" cultivated land in coal mining areas,as well as technologies for improving quality of cultivated land consolidated from coal mining subsided land.展开更多
In east China , a great amount of water-logged land is caused by coal mining subsidence,which results in arduous reclamation tasks. Taking Hanqiao Coal Mine in Xuzhou as an example, this paper introduces a new reclama...In east China , a great amount of water-logged land is caused by coal mining subsidence,which results in arduous reclamation tasks. Taking Hanqiao Coal Mine in Xuzhou as an example, this paper introduces a new reclamation method suitable for suhsided land caused by coal mining with high phreatic level in east China. The new method consists of two respects: 1 ) engineering reclamation measure is a non-filled method which mainly applies dredging approach ; 2 ) biological reclamation measure is a high beneficial pattern, which mainly makes use of dikes and ponds. The new engincering and biological measures of reclamation have been used widespreadly in Xuzhou mining area. Considerable economic benefits and social and environmental effects have been obtained.展开更多
[Objective] The study aimed to discuss the effects of coal mining subsided water area on temperature change in Huaibei coal mine. [Method] Based on the data of monthly temperature from 1957 to 2007 recorded by Suixi ...[Objective] The study aimed to discuss the effects of coal mining subsided water area on temperature change in Huaibei coal mine. [Method] Based on the data of monthly temperature from 1957 to 2007 recorded by Suixi （coal mining subsided water area） and Fuyang stations （control）, the effects of coal mining subsided water area on temperature change in Huaibei coal mine were discussed using linear trend estimation and comparative analysis methods. [Result] Spring, autumn, winter and annual average temperatures of coal mining subsided water area （Suixi） were increased in the last 51 years, and the increase of winter temperature was mostly significant with a tendency rate of 0.49 ℃/10 a. Meanwhile, annual temperature range of coal mining subsided water area was decreased from 1957 to 2007. Temperatures of Suixi in four seasons were lower than those of Fuyang from the 1960s to 1990s, and temperatures of coal mining subsided water area （Suixi） were higher than those of Fuyang in spring, autumn and winter but lower than those of Fuyang in summer from 2000 to 2007. [ Result] Coal mining subsided water area had certain effects on temperature change of Huaibei coal mine.展开更多
The subsided water areas with different times of subsidence are chosen to monitor the physicochemical indexes and heavy metal elements. The results indicate that subsided water areas are polluted in different degree. ...The subsided water areas with different times of subsidence are chosen to monitor the physicochemical indexes and heavy metal elements. The results indicate that subsided water areas are polluted in different degree. Some physicochemical indexes of subsided water areas are increased with the development of the subsidence and are changed with the changing of the season. The concentration of As, Cd, Cu, Pb, Se, Zn of subsided water areas is less than national fishery, and surface water quality standards of China , except Hg. And the quality of subsided water hasn＇t been polluted by heavy metal seriously. Analyzing and appraising the quality of the subsided water can give a reasonable data as basis in using the subsided water resource.展开更多
Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical ...Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical GIS spatial technology. Using the Huainan mining area as an example, we calculated the modulus of erosion, its volume and classified the grade of soil erosion for both the original area and the subsidence basin. The results show that the maximum modulus of erosion and the volume of erosion of the subsi- dence basin without water logging would increase by 78% and 23% respectively compared with the ori- ginal situation. The edge of the subsidence basin, where the land subsidence was uneven, is subject to the greatest acceleration in soil erosion. In the situation of water logging after subsidence, the maximum modulus of erosion would decrease if the accumulated slope length were reduced. This maximum mod- ulus around the water logged area within the subsidence basin is equal to that without water logging, while the total volume of erosion decreases. Therefore, mining subsidence aggravates soil erosion espe- cially at the edge of basins where water and soil conservation measures should be taken.展开更多
Following the description of the subsided land treatment methods and the characteristics of the related land reclamation,the necessity and emergency of the land reclamation work is stressed.To cope with the related pr...Following the description of the subsided land treatment methods and the characteristics of the related land reclamation,the necessity and emergency of the land reclamation work is stressed.To cope with the related problems,dynamic prediction of the ground subsidence in different time periods and areas is made based on the laws governing the rock and ground movements and line with a mine’s future mining plan.It is proposed to carry out dynamic management of subsided land reclamation work in mining area,in order to tackle the previous and current issues confronted in the processes of land requisition,compensation and land reclamation.It is intended to provide,through the above-mentioned efforts,the technical and decision-making basis for the mining authorities concerned to better solve the problems relating to land requisition and reclamation in the future,and relocation of villages for facilitating the mining of the underground coal depositing and realizing the sustainable development of mining enterprises.展开更多
In this paper, changes in the amounts of organic carbon and black carbon in reclaimed soil were studied. The subsidence area was in a Xuzhou coal mining area that is part of a national land reclamation demonstration a...In this paper, changes in the amounts of organic carbon and black carbon in reclaimed soil were studied. The subsidence area was in a Xuzhou coal mining area that is part of a national land reclamation demonstration area. The significance of the paper is to explain the law of quality changes of reclaimed soil, improve the soil reclamation process and promote the sustainable use of soil in mining areas. In the study, four kinds of soils were collected using four land reclamation methods： coal gangue filling（CGF）, mixed flat reclamation（MFR）, mud pump filling（MPF） and fly ash filling（FAF）; soil from the subsided area（SS） was used as the control. Organic carbon and black carbon on content were determined by elemental analysis, potassium dichromate titration and other methods. The result shows that reclamation methods do have an influence on the organic carbon and black carbon content in subsidence soil. The content of organic carbon and black carbon at different soil depths varies the most in FAF. Regression analysis of black carbon and organic carbon contents from the four different reclamation methods show that the levels are significant in all cases. Therefore, there is no obvious relationship between the proportion of black carbon and the accumulation of organic carbon in the study area.展开更多
Small Baseline Subset Interferometric Synthetic Aperture Radar(SBAS-In SAR)is widely used for deformation monitoring in mining regions.However,phase unwrapping errors often limit its effectiveness in areas with large-...Small Baseline Subset Interferometric Synthetic Aperture Radar(SBAS-In SAR)is widely used for deformation monitoring in mining regions.However,phase unwrapping errors often limit its effectiveness in areas with large-gradient displacements.We propose a novel approach integrating spatiotemporal modeling to address this limitation and improve phase unwrapping.The Simplified Rectangular Dislocation Model(SRDM)simplifies the phase recovery process by reducing model parameters and improving efficiency in large-gradient deformation zones.Subsequently,the Power Exponential Knothe Model(PEKM)is applied to invert the deformation time series and restore the deformation phase from the time dimension.We validated this method using Sentinel-1 and Radarsat-2 data in the Majialiang Coalfield,China.The results demonstrate that the approach achieved 5%(Sentinel-1)and 14%(Radarsat-2)phase range extensions,elevating maximum detectable phase values from 120/100 rad to 160 rad for respective datasets,while the proportions of pixel points with restored phase exceeding 8 rad(-0.035 m)were 17.4%and 32.1%.The proposed method outperformed conventional techniques in resolving phase discontinuities,demonstrating strong adaptability.This approach significantly enhances subsidence monitoring accuracy and supports sustainable mining operations in coal-dependent regions.展开更多
The innovative utilization of Yellow River sediment to reclaim coal-mined subsided lands addresses dual environmental challenges by offering a sustainable remediation technique.However,efficient water drainage constit...The innovative utilization of Yellow River sediment to reclaim coal-mined subsided lands addresses dual environmental challenges by offering a sustainable remediation technique.However,efficient water drainage constitutes a significant hurdle in this context.The strategic placement of nonwoven geotextile at the tail end of the fill sections has ameliorated fine sediment loss and drainage efficacy issues.This study assesses various nonwoven geotextile grades for their effectiveness in moisture expulsion,integrating comprehensive evaluations and simulation tests of pivotal processes.The findings reveal that selected nonwoven geotextiles(N1,N2,T1,T2,T3,T4)demonstrate appropriate apparent opening size(AOS)and permeability,coupled with clogging resistance,aligning with theoretical criteria for soil conservation,water permeation,and blockage prevention.Crucial to the nonwoven geotextile’s clogging are factors such as apparent opening size(AOS),thickness,permeability,load capacity,gradient ratio(GR),and sediment retention-all requiring meticulous selection for real-world application.The choice of nonwoven geotextile in the drainage of Yellow River sediment reclaimed lands must hinge on a holistic assessment framework,encompassing retention,permeability,anti-clogging attributes,and additional performance metrics,to ensure that the materials fulfill the specific technical standards while remaining cost-effective.This study provides valuable insights into the selection and application of geotextiles in Yellow River sediment-backfilled reclamation drainage projects,contributing to the advancement of mine ecological restoration practices,particularly in the context of Yellow River sediment-backfilled reclamation projects.展开更多
Population growth leads to increased utilization of water resources.One of these resources is groundwater,which has steadily declined each year.The depletion of these resources brings about various environmental chall...Population growth leads to increased utilization of water resources.One of these resources is groundwater,which has steadily declined each year.The depletion of these resources brings about various environmental challenges.The present study aimed to explore the relationship between groundwater fluctuations and land subsidence in the Malayer Plain,Iran,focusing on quantifying subsidence resulting from groundwater extraction.Using Sentinel-1 satellite data(2014–2019)and monthly piezometric measurements(1996–2018),the analysis revealed an average deformation velocity of–6.3 cm yr–1,with accumulated subsidence of–32 cm over the 2014–2019 period.The maximum subsidence rate reached 10.3 cm yr–1 in areas of intensive agricultural activity.A wavelet-PCA spatiotemporal analysis of groundwater fluctuations identified critical multi-scale patterns strongly correlated with subsidence trends.Regression analysis between subsidence rates and groundwater fluctuations at various wavelet decomposition levels explained 75%of the variance(R2=0.75),indicating that intermediate-scale groundwater declines were the primary drivers of subsidence.Furthermore,land use analysis using Landsat data(1999–2021)revealed a 6230-ha increase in irrigated farmland,contributing to heightened groundwater extraction and subsidence rates.These findings highlight the critical need for sustainable groundwater management to mitigate the risks of continued subsidence in the region.展开更多
Ground Penetrating Radar(GPR)is a widely used method that is non-destructive for underground or subsurface detection.It is used in various fields and has proved to be reliable and effective.This research focuses on de...Ground Penetrating Radar(GPR)is a widely used method that is non-destructive for underground or subsurface detection.It is used in various fields and has proved to be reliable and effective.This research focuses on detecting the presence of air cavities using GPR and analyzing the radargram output based on the compactness of soil and different frequencies.The compactness is used to illustrate the presence of cavities underground artificially.The research examines how variations in the compactness of soil affect the radargram response in showing the presence of cavities using different frequencies.Experimental results demonstrate that lower permittivity materials enhance signal penetration but reduce reflection contrast,whereas higher permittivity materials result in stronger reflections,improving cavity detection.The findings highlight the importance of frequency selection and material properties in optimizing GPR surveys for subsurface anomaly detection,and by having artificially created cavities,the results can be studied to see the changes.展开更多
Atmospheric phase delay,primarily caused by water vapor in the troposphere,is a major source of error in InSAR measurements,especially for land subsidence monitoring.This study integrates GNSS and GACOS data to correc...Atmospheric phase delay,primarily caused by water vapor in the troposphere,is a major source of error in InSAR measurements,especially for land subsidence monitoring.This study integrates GNSS and GACOS data to correct tropospheric delay and enhance InSAR accuracy in Banting,Selangor.A total of 27 Sentinel-1A images,14GNSS stations,and 27 corresponding GACOS ZTD mapswere used tomonitor subsidence between 2023 and 2025.The InSAR data were processed using SNAP,StaMPS,and the TRAIN toolbox,incorporating both GNSS-and GACOS-derived ZTD corrections.The results show that applying atmospheric correction improved the estimated deformation range from−14.9 mm/year(min)and 9.1 mm/year(max)to−14.7 and 9.2 mm/year usingGACOS ZTD.Further enhancement was achieved by integrating GNSS and GACOS ZTD,resulting in deformation estimates ranging from−15.4 to 9.3 mm/year.Validation against reference GNSS data from the MERU MyRTKnet station revealed that the integrated correction yielded the lowest RMSE of 0.025,compared to 0.029 with GACOS-only correction and 0.03 without any correction.Overall,the integration of GNSS-and GACOS-derived atmospheric corrections significantly improved the accuracy of InSAR-based subsidence measurements,offering a promising approach for precise ground deformation monitoring in humid,tropical environments.展开更多
The North China Plain is vital hub for agricultural production and urban development.However,decades of excessive groundwater extraction have resulted on significant land subsidence,posing severe threats to the region...The North China Plain is vital hub for agricultural production and urban development.However,decades of excessive groundwater extraction have resulted on significant land subsidence,posing severe threats to the region's socio-economic stability and sustainable development.The relationship between land deformation and groundwater storage Anomalies in this region remains insufficiently understood,and the driving factors behind land subsidence require further exploration.This study employs downscaled GRACE and SBAS InSAR technologies to monitor and analyze land subsidence and groundwater storage Anoma-lies in four representative cities of the North China Plain:Beijing,Tianjin,Cangzhou,and Hengshui.Using geodetector methods,the study investigates the driving factors of land subsidence,incorporating both natu-ral environmental and human activity factors.The results indicate that:(1)Groundwater storage in the North China Plain generally exhibited an overall declining trend from 2002 to 2022,with the rate of decrease weakening from southwest to northeast,showing a clear spatial clustering pattern.(2)While,land subsidence rates in the main urban areas of each city were relatively low,severe subsidence persisted in the surrounding suburban and rural areas.(3)The temporal trends of land subsidence were consistent with changes in groundwater storage across all cities.(4)Groundwater storage Anomalies emerged as the most significant factor influencing the spatial distribution of land subsidence,with a q-value of 0.387,followed by factors such as DEM,evapotranspiration,and rainfall.Seasonal characteristics were evident in land deformation corresponding to groundwater storage Anomalies:During the spring and summer irrigation periods,land subsidence occurred due to groundwater depletion,while in autumn and winter,the surface uplifted with increased groundwater storage.In Cangzhou and Hengshui,excessive deep groundwater extraction caused a lagged response in land subsidence relative to groundwater storage Anomalies.Further-more,interaction among various factors significantly amplified their influence on land subsidence.The interaction between groundwater storage Anomalies and rainfall had the strongest combined effect,under-scoring its critical role in shaping land subsidence in the study area.The findings offer valuable insights for the scientific prevention and management of land subsidence in the North China Plain.展开更多
Land subsidence significantly impacts the accuracy of the National Elevation Datum in China.In order to solve this issue,a dynamic and economical way was proposed to update the National Elevation Datum with the assist...Land subsidence significantly impacts the accuracy of the National Elevation Datum in China.In order to solve this issue,a dynamic and economical way was proposed to update the National Elevation Datum with the assistance of InSAR in the North China Plain,which served as the research area.Moreover,the GNSS result was used to correct the InSAR result for the vertical deformation field,which has a relatively unified deformation reference.By integrating the vertical deformation field with the national elevation control point,an analysis and evaluation of changes in the National Elevation Datum were conducted.In addition,a regional remeasurement scheme was formulated to achieve dynamic updates and mainte-nance of the National Elevation Datum on a regional scale.Through data acquisition and processing,we successfully improved reliability within the main subsidence areas for future use.As a result,updating the elevation values utilize a regional update method,and a dynamic and economical technical process to update the National Elevation Datum is shown in the study.展开更多
The expansion of construction land on slopes in mountainous cities like Lanzhou has addressed the shortage of flat land but compromised slope stability,leading to uneven land subsidence and risks to infrastructure.Thi...The expansion of construction land on slopes in mountainous cities like Lanzhou has addressed the shortage of flat land but compromised slope stability,leading to uneven land subsidence and risks to infrastructure.This study assessed the land subsidence before and after urban expansion in five areas of Lanzhou by using slope spectrum construction method and gradient expansion intensity measurement that integrated with SBAS-InSAR technology.The results show that construction land on slopes over 20°increased significantly,accounting for 16%of new construction land.The average slope spectrum index was 4.02,with the upper slope limit rising by 8.2°.The land subsidence rate threshold increased by 10 mm/a,and the proportion of pixels experiencing subsidence greater than 5 mm/year rose from 3.63%to 5.24%.Increased construction intensity on slopes caused higher and faster subsidence,which diminished with greater distance from the expansion areas.Areas with slopes between 10°and 25°saw the greatest acceleration in subsidence.Geological composition,building density,groundwater exploitation,and cut-and-fill thickness collectively influence land subsidence rates.This study provides a scientific basis for mitigating geological disaster risks and promoting safe urban development in mountainous cities.展开更多
The Small Baseline Subset InSAR(SBAS-InSAR)and unmanned aerial vehicles(UAVs)as common ocean-land technologies,have been extensively applied in subsidence,glacial movement,surface deformation,and maritime positioning ...The Small Baseline Subset InSAR(SBAS-InSAR)and unmanned aerial vehicles(UAVs)as common ocean-land technologies,have been extensively applied in subsidence,glacial movement,surface deformation,and maritime positioning and navigation.A novel method integrating SBAS-InSAR and UAV photogrammetry is used to analyze ground subsidence deformation in the Gesar gold mine located in Maqu,Northwest China.This approach uses SBAS-InSAR to calculate two-dimensional deformation data for capturing ascending and descending measurements.This method can provide precise information on small-sized deformations within mining regions.The deformation data obtained from UAVs and the vertical deformation data derived from InSAR are integrated to generate comprehensive and accurate ground subsidence data from the mining district.Results demonstrate that using a combined InSAR(vertical)and UAV technique to analyze surface subsidence in mining districts resolves inconsistency between the line-of-sight and deformation orientations.Furthermore,the incoherence issue of InSAR in regions with large deformation gradients is addressed,while the inherent errors of UAV monitoring of mining surface subsidence are mitigated.The genetic algorithm(GA)-backpropagation(BP)neural network algorithm is combined with InSAR data to predict subsidence in collapsed areas.As observed,the GA-BP algorithm has the smallest residual under the same training samples.Therefore,the GA-BP neural network model can effectively predict surface subsidence in mining areas and can be used for subsequent subsidence prediction.展开更多
Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and...Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and present hazards that can be essential to better predict risks in urbanised deltas.This paper aims to identify the effect of a long-term evolution of the prograded plain of the Tiber Delta in using current ground surface variations and geohistorical data.This study applies GIS(Geographic Information System)tools to LiDAR(Light Detection and Ranging)-derived DEM(Digital Elevation Model)data combined with stratigraphical data,aerial photography interpretation and old maps.The main outcome shows areas of subsidence are primarily located in the central part of the Tiber Delta.Lower heights at the river mouth are due to subsidence and specific lower morphologies associated with fast progradation phases,while similar low heights just north in the area of the international airport of Rome are due to subsidence alone.Subsidence under the airport is associated with the compaction of the silty clay infill of the Late Pleistocene Tiber Valley mostly deposited during the Holocene transgressive period.Only observed in the airport area,the presence of washover fans and the large extent of paleolagoons reveal the kind of risks that are increased by this subsidence.This study demonstrates that the densely urbanised central part of the Tiber Delta faces higher risks of marine submersion and coastal flooding considering ongoing relative sea level change.It also contributes to show the importance to better characterise past coastal morphologies to identify areas prone to subsidence.展开更多
Underground coal mining induces significant surface deformation and environmental damage,particularly in deeply buried mining areas with thin bedrock and thick alluvial layers.Based on the case study of the Zhaogu No....Underground coal mining induces significant surface deformation and environmental damage,particularly in deeply buried mining areas with thin bedrock and thick alluvial layers.Based on the case study of the Zhaogu No.2 coal mine in Xinxiang City,Henan Province,China,this study employs a comprehensive research methodology,integrating field investigations,numerical simulations,and theoretical analyses,to explore the surface subsidence features at deeply buried mining areas with thin bedrock and thick alluvial layers,to reveal the effect of alluvial thickness on the surface subsidence characteristics.The findings indicate that the surface subsidence areas span 4.2 km2 with an advanced influence distance of 540 m.The rate of surface subsidence primarily depends on the panel's position and its advancing rate.Moreover,the thickness of the alluvial layer amplifies both the extent and magnitude of surface deformation.The displacement of overlying rock primarily exhibits a two-stage progression:the thin bedrock control stage and the alluvial control stage.In the thin bedrock control stage,surface subsidence initiates with relatively low subsidence values and amplitudes.Subsequently,in the alluvial control stage,surface subsidence accelerates,leading to a rapid increase in both subsidence values and amplitudes.These characteristics of rock formation displacement result in distinct phases of surface subsidence.Furthermore,the paper addresses the utilization of surface subsidence areas and proposes a method for calculating reservoir storage capacity in these areas.According to calculations,the storage capacity amounts to 1.05e7 m^(3).The research findings provide valuable insights into the surface subsidence laws in regions with similar geological conditions and practical implications for the management and utilization of subsided areas.展开更多
0 INTRODUCTION Due to the rapid population growth and the accelerated urbanization process,the contradiction between the demand for expanding ground space and the limited available land scale is becoming increasingly ...0 INTRODUCTION Due to the rapid population growth and the accelerated urbanization process,the contradiction between the demand for expanding ground space and the limited available land scale is becoming increasingly prominent.China has implemented and completed several largescale land infilling and excavation projects(Figure 1),which have become the main way to increase land resources and expand construction land.展开更多
Based on the characteristics of strata movement of solid backfilling mining technology, the surface subsidence prediction method based on the equivalent mining height theory was proposed, and the parameters selection ...Based on the characteristics of strata movement of solid backfilling mining technology, the surface subsidence prediction method based on the equivalent mining height theory was proposed, and the parameters selection guideline of this method was also described. While comparing the parameters of caving mining with equivalent height, the subsidence efficient can be calculated according to the mining height and bulk factor of sagging zone and fracture zone, the tangent of main influence angle of solid backfilling mining is reduced by 0.2-0.5（while it cannot be less than 1.0）. For sake of safety, offset of the inflection point is set to zero, and other parameters, such as horizontal movement coefficient and main propagation angle are equal to the corresponding parameters of caving mining with equivalent height. In the last part, a case study of solid backfilling mining subsidence prediction was described. The results show the applicability of this method and the difference of the maximum subsidence point between the prediction and the observation is less than 5%.展开更多
基金Supported by the National Science and Technology Project in the Twelfth Five-Year Plan Period(Grant No.:2011BAD04B03)
文摘The evaluation of consolidated cultivated land quality can provide basic information for how to perfect the program of land consolidation,as well as a reference for the dynamic monitoring of farmland quality in mining area. Based on the consultation and analysis of related literature,we can conclude that: firstly,most scholars focus on soil consolidation,while consider little about land use and economic condition. Secondly,foreign scholars usually use crop yields to judge the success of land consolidation,while domestic scholars have been evaluated the quality of consolidated cultivated land synthetically from several aspects,such as soil fertility,soil environmental quality,and farmland infrastructure conditions. Specifically,most of the evaluations are static,and indicators are different. Besides,the quality of consolidated cultivated land is generally low,and it lacks systematic research on technologies for improving quality of cultivated land consolidated from coal mining subsided land. It is concluded that future researches should focus on establishing scientific and feasible evaluation system to realize comparison of quality change in the dynamic course of " undisturbed-subsided-consolidated" cultivated land in coal mining areas,as well as technologies for improving quality of cultivated land consolidated from coal mining subsided land.
文摘In east China , a great amount of water-logged land is caused by coal mining subsidence,which results in arduous reclamation tasks. Taking Hanqiao Coal Mine in Xuzhou as an example, this paper introduces a new reclamation method suitable for suhsided land caused by coal mining with high phreatic level in east China. The new method consists of two respects: 1 ) engineering reclamation measure is a non-filled method which mainly applies dredging approach ; 2 ) biological reclamation measure is a high beneficial pattern, which mainly makes use of dikes and ponds. The new engincering and biological measures of reclamation have been used widespreadly in Xuzhou mining area. Considerable economic benefits and social and environmental effects have been obtained.
基金Supported by the Key Project of Provincial Natural Science Research for Colleges and Universities in Anhui Province, China ( KJ2013A244)
文摘[Objective] The study aimed to discuss the effects of coal mining subsided water area on temperature change in Huaibei coal mine. [Method] Based on the data of monthly temperature from 1957 to 2007 recorded by Suixi （coal mining subsided water area） and Fuyang stations （control）, the effects of coal mining subsided water area on temperature change in Huaibei coal mine were discussed using linear trend estimation and comparative analysis methods. [Result] Spring, autumn, winter and annual average temperatures of coal mining subsided water area （Suixi） were increased in the last 51 years, and the increase of winter temperature was mostly significant with a tendency rate of 0.49 ℃/10 a. Meanwhile, annual temperature range of coal mining subsided water area was decreased from 1957 to 2007. Temperatures of Suixi in four seasons were lower than those of Fuyang from the 1960s to 1990s, and temperatures of coal mining subsided water area （Suixi） were higher than those of Fuyang in spring, autumn and winter but lower than those of Fuyang in summer from 2000 to 2007. [ Result] Coal mining subsided water area had certain effects on temperature change of Huaibei coal mine.
文摘The subsided water areas with different times of subsidence are chosen to monitor the physicochemical indexes and heavy metal elements. The results indicate that subsided water areas are polluted in different degree. Some physicochemical indexes of subsided water areas are increased with the development of the subsidence and are changed with the changing of the season. The concentration of As, Cd, Cu, Pb, Se, Zn of subsided water areas is less than national fishery, and surface water quality standards of China , except Hg. And the quality of subsided water hasn＇t been polluted by heavy metal seriously. Analyzing and appraising the quality of the subsided water can give a reasonable data as basis in using the subsided water resource.
基金supported by the National Environ-mental Protection Specialized Fund for Commonwealth Industry(No.200809128)the Fundamental Research Funds for the Cen-tral Universities(No.2011RC37)
文摘Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical GIS spatial technology. Using the Huainan mining area as an example, we calculated the modulus of erosion, its volume and classified the grade of soil erosion for both the original area and the subsidence basin. The results show that the maximum modulus of erosion and the volume of erosion of the subsi- dence basin without water logging would increase by 78% and 23% respectively compared with the ori- ginal situation. The edge of the subsidence basin, where the land subsidence was uneven, is subject to the greatest acceleration in soil erosion. In the situation of water logging after subsidence, the maximum modulus of erosion would decrease if the accumulated slope length were reduced. This maximum mod- ulus around the water logged area within the subsidence basin is equal to that without water logging, while the total volume of erosion decreases. Therefore, mining subsidence aggravates soil erosion espe- cially at the edge of basins where water and soil conservation measures should be taken.
文摘Following the description of the subsided land treatment methods and the characteristics of the related land reclamation,the necessity and emergency of the land reclamation work is stressed.To cope with the related problems,dynamic prediction of the ground subsidence in different time periods and areas is made based on the laws governing the rock and ground movements and line with a mine’s future mining plan.It is proposed to carry out dynamic management of subsided land reclamation work in mining area,in order to tackle the previous and current issues confronted in the processes of land requisition,compensation and land reclamation.It is intended to provide,through the above-mentioned efforts,the technical and decision-making basis for the mining authorities concerned to better solve the problems relating to land requisition and reclamation in the future,and relocation of villages for facilitating the mining of the underground coal depositing and realizing the sustainable development of mining enterprises.
基金National Natural Science Foundation of China(41201186)
文摘In this paper, changes in the amounts of organic carbon and black carbon in reclaimed soil were studied. The subsidence area was in a Xuzhou coal mining area that is part of a national land reclamation demonstration area. The significance of the paper is to explain the law of quality changes of reclaimed soil, improve the soil reclamation process and promote the sustainable use of soil in mining areas. In the study, four kinds of soils were collected using four land reclamation methods： coal gangue filling（CGF）, mixed flat reclamation（MFR）, mud pump filling（MPF） and fly ash filling（FAF）; soil from the subsided area（SS） was used as the control. Organic carbon and black carbon on content were determined by elemental analysis, potassium dichromate titration and other methods. The result shows that reclamation methods do have an influence on the organic carbon and black carbon content in subsidence soil. The content of organic carbon and black carbon at different soil depths varies the most in FAF. Regression analysis of black carbon and organic carbon contents from the four different reclamation methods show that the levels are significant in all cases. Therefore, there is no obvious relationship between the proportion of black carbon and the accumulation of organic carbon in the study area.
基金Open Research Fund of Guangxi Key Laboratory of Culture and Tourism Smart Technology,Guilin Tourism UniversityGuangxi University young and middle-aged teachers research basic ability improvement project(2025KY0961)。
文摘Small Baseline Subset Interferometric Synthetic Aperture Radar(SBAS-In SAR)is widely used for deformation monitoring in mining regions.However,phase unwrapping errors often limit its effectiveness in areas with large-gradient displacements.We propose a novel approach integrating spatiotemporal modeling to address this limitation and improve phase unwrapping.The Simplified Rectangular Dislocation Model(SRDM)simplifies the phase recovery process by reducing model parameters and improving efficiency in large-gradient deformation zones.Subsequently,the Power Exponential Knothe Model(PEKM)is applied to invert the deformation time series and restore the deformation phase from the time dimension.We validated this method using Sentinel-1 and Radarsat-2 data in the Majialiang Coalfield,China.The results demonstrate that the approach achieved 5%(Sentinel-1)and 14%(Radarsat-2)phase range extensions,elevating maximum detectable phase values from 120/100 rad to 160 rad for respective datasets,while the proportions of pixel points with restored phase exceeding 8 rad(-0.035 m)were 17.4%and 32.1%.The proposed method outperformed conventional techniques in resolving phase discontinuities,demonstrating strong adaptability.This approach significantly enhances subsidence monitoring accuracy and supports sustainable mining operations in coal-dependent regions.
基金funded by the National Natural Science Foundation of China(Grant No.41771542).
文摘The innovative utilization of Yellow River sediment to reclaim coal-mined subsided lands addresses dual environmental challenges by offering a sustainable remediation technique.However,efficient water drainage constitutes a significant hurdle in this context.The strategic placement of nonwoven geotextile at the tail end of the fill sections has ameliorated fine sediment loss and drainage efficacy issues.This study assesses various nonwoven geotextile grades for their effectiveness in moisture expulsion,integrating comprehensive evaluations and simulation tests of pivotal processes.The findings reveal that selected nonwoven geotextiles(N1,N2,T1,T2,T3,T4)demonstrate appropriate apparent opening size(AOS)and permeability,coupled with clogging resistance,aligning with theoretical criteria for soil conservation,water permeation,and blockage prevention.Crucial to the nonwoven geotextile’s clogging are factors such as apparent opening size(AOS),thickness,permeability,load capacity,gradient ratio(GR),and sediment retention-all requiring meticulous selection for real-world application.The choice of nonwoven geotextile in the drainage of Yellow River sediment reclaimed lands must hinge on a holistic assessment framework,encompassing retention,permeability,anti-clogging attributes,and additional performance metrics,to ensure that the materials fulfill the specific technical standards while remaining cost-effective.This study provides valuable insights into the selection and application of geotextiles in Yellow River sediment-backfilled reclamation drainage projects,contributing to the advancement of mine ecological restoration practices,particularly in the context of Yellow River sediment-backfilled reclamation projects.
文摘Population growth leads to increased utilization of water resources.One of these resources is groundwater,which has steadily declined each year.The depletion of these resources brings about various environmental challenges.The present study aimed to explore the relationship between groundwater fluctuations and land subsidence in the Malayer Plain,Iran,focusing on quantifying subsidence resulting from groundwater extraction.Using Sentinel-1 satellite data(2014–2019)and monthly piezometric measurements(1996–2018),the analysis revealed an average deformation velocity of–6.3 cm yr–1,with accumulated subsidence of–32 cm over the 2014–2019 period.The maximum subsidence rate reached 10.3 cm yr–1 in areas of intensive agricultural activity.A wavelet-PCA spatiotemporal analysis of groundwater fluctuations identified critical multi-scale patterns strongly correlated with subsidence trends.Regression analysis between subsidence rates and groundwater fluctuations at various wavelet decomposition levels explained 75%of the variance(R2=0.75),indicating that intermediate-scale groundwater declines were the primary drivers of subsidence.Furthermore,land use analysis using Landsat data(1999–2021)revealed a 6230-ha increase in irrigated farmland,contributing to heightened groundwater extraction and subsidence rates.These findings highlight the critical need for sustainable groundwater management to mitigate the risks of continued subsidence in the region.
文摘Ground Penetrating Radar(GPR)is a widely used method that is non-destructive for underground or subsurface detection.It is used in various fields and has proved to be reliable and effective.This research focuses on detecting the presence of air cavities using GPR and analyzing the radargram output based on the compactness of soil and different frequencies.The compactness is used to illustrate the presence of cavities underground artificially.The research examines how variations in the compactness of soil affect the radargram response in showing the presence of cavities using different frequencies.Experimental results demonstrate that lower permittivity materials enhance signal penetration but reduce reflection contrast,whereas higher permittivity materials result in stronger reflections,improving cavity detection.The findings highlight the importance of frequency selection and material properties in optimizing GPR surveys for subsurface anomaly detection,and by having artificially created cavities,the results can be studied to see the changes.
文摘Atmospheric phase delay,primarily caused by water vapor in the troposphere,is a major source of error in InSAR measurements,especially for land subsidence monitoring.This study integrates GNSS and GACOS data to correct tropospheric delay and enhance InSAR accuracy in Banting,Selangor.A total of 27 Sentinel-1A images,14GNSS stations,and 27 corresponding GACOS ZTD mapswere used tomonitor subsidence between 2023 and 2025.The InSAR data were processed using SNAP,StaMPS,and the TRAIN toolbox,incorporating both GNSS-and GACOS-derived ZTD corrections.The results show that applying atmospheric correction improved the estimated deformation range from−14.9 mm/year(min)and 9.1 mm/year(max)to−14.7 and 9.2 mm/year usingGACOS ZTD.Further enhancement was achieved by integrating GNSS and GACOS ZTD,resulting in deformation estimates ranging from−15.4 to 9.3 mm/year.Validation against reference GNSS data from the MERU MyRTKnet station revealed that the integrated correction yielded the lowest RMSE of 0.025,compared to 0.029 with GACOS-only correction and 0.03 without any correction.Overall,the integration of GNSS-and GACOS-derived atmospheric corrections significantly improved the accuracy of InSAR-based subsidence measurements,offering a promising approach for precise ground deformation monitoring in humid,tropical environments.
基金supported by the Fundamental Research Funds for Central Public Welfare Research Institutes,CAGS(Project No.KY202302)China Geological Survey Project(DD20230719)China Geological Survey Project(DD20230427)。
文摘The North China Plain is vital hub for agricultural production and urban development.However,decades of excessive groundwater extraction have resulted on significant land subsidence,posing severe threats to the region's socio-economic stability and sustainable development.The relationship between land deformation and groundwater storage Anomalies in this region remains insufficiently understood,and the driving factors behind land subsidence require further exploration.This study employs downscaled GRACE and SBAS InSAR technologies to monitor and analyze land subsidence and groundwater storage Anoma-lies in four representative cities of the North China Plain:Beijing,Tianjin,Cangzhou,and Hengshui.Using geodetector methods,the study investigates the driving factors of land subsidence,incorporating both natu-ral environmental and human activity factors.The results indicate that:(1)Groundwater storage in the North China Plain generally exhibited an overall declining trend from 2002 to 2022,with the rate of decrease weakening from southwest to northeast,showing a clear spatial clustering pattern.(2)While,land subsidence rates in the main urban areas of each city were relatively low,severe subsidence persisted in the surrounding suburban and rural areas.(3)The temporal trends of land subsidence were consistent with changes in groundwater storage across all cities.(4)Groundwater storage Anomalies emerged as the most significant factor influencing the spatial distribution of land subsidence,with a q-value of 0.387,followed by factors such as DEM,evapotranspiration,and rainfall.Seasonal characteristics were evident in land deformation corresponding to groundwater storage Anomalies:During the spring and summer irrigation periods,land subsidence occurred due to groundwater depletion,while in autumn and winter,the surface uplifted with increased groundwater storage.In Cangzhou and Hengshui,excessive deep groundwater extraction caused a lagged response in land subsidence relative to groundwater storage Anomalies.Further-more,interaction among various factors significantly amplified their influence on land subsidence.The interaction between groundwater storage Anomalies and rainfall had the strongest combined effect,under-scoring its critical role in shaping land subsidence in the study area.The findings offer valuable insights for the scientific prevention and management of land subsidence in the North China Plain.
基金supported by the Scientific and Technological Innovation Project of SHASG(SCK2022-01)National Key Research and Development Program of China(2016YFC0803109)。
文摘Land subsidence significantly impacts the accuracy of the National Elevation Datum in China.In order to solve this issue,a dynamic and economical way was proposed to update the National Elevation Datum with the assistance of InSAR in the North China Plain,which served as the research area.Moreover,the GNSS result was used to correct the InSAR result for the vertical deformation field,which has a relatively unified deformation reference.By integrating the vertical deformation field with the national elevation control point,an analysis and evaluation of changes in the National Elevation Datum were conducted.In addition,a regional remeasurement scheme was formulated to achieve dynamic updates and mainte-nance of the National Elevation Datum on a regional scale.Through data acquisition and processing,we successfully improved reliability within the main subsidence areas for future use.As a result,updating the elevation values utilize a regional update method,and a dynamic and economical technical process to update the National Elevation Datum is shown in the study.
基金National Natural Science Foundation of China(Grant No.42271214)National Key R&D Program of China(Grant No.2022YFC3800700)+1 种基金Key Research Program of Gansu Province(Grant No.23ZDKA0004)Natural Science Foundation of Gansu Province(Grant No.21JR7RA281).
文摘The expansion of construction land on slopes in mountainous cities like Lanzhou has addressed the shortage of flat land but compromised slope stability,leading to uneven land subsidence and risks to infrastructure.This study assessed the land subsidence before and after urban expansion in five areas of Lanzhou by using slope spectrum construction method and gradient expansion intensity measurement that integrated with SBAS-InSAR technology.The results show that construction land on slopes over 20°increased significantly,accounting for 16%of new construction land.The average slope spectrum index was 4.02,with the upper slope limit rising by 8.2°.The land subsidence rate threshold increased by 10 mm/a,and the proportion of pixels experiencing subsidence greater than 5 mm/year rose from 3.63%to 5.24%.Increased construction intensity on slopes caused higher and faster subsidence,which diminished with greater distance from the expansion areas.Areas with slopes between 10°and 25°saw the greatest acceleration in subsidence.Geological composition,building density,groundwater exploitation,and cut-and-fill thickness collectively influence land subsidence rates.This study provides a scientific basis for mitigating geological disaster risks and promoting safe urban development in mountainous cities.
基金funded by the Project from the Maqu Branch of Gannan Tibetan Autonomous Prefecture Ecological Environment Bureau,China(No.33412021021)。
文摘The Small Baseline Subset InSAR(SBAS-InSAR)and unmanned aerial vehicles(UAVs)as common ocean-land technologies,have been extensively applied in subsidence,glacial movement,surface deformation,and maritime positioning and navigation.A novel method integrating SBAS-InSAR and UAV photogrammetry is used to analyze ground subsidence deformation in the Gesar gold mine located in Maqu,Northwest China.This approach uses SBAS-InSAR to calculate two-dimensional deformation data for capturing ascending and descending measurements.This method can provide precise information on small-sized deformations within mining regions.The deformation data obtained from UAVs and the vertical deformation data derived from InSAR are integrated to generate comprehensive and accurate ground subsidence data from the mining district.Results demonstrate that using a combined InSAR(vertical)and UAV technique to analyze surface subsidence in mining districts resolves inconsistency between the line-of-sight and deformation orientations.Furthermore,the incoherence issue of InSAR in regions with large deformation gradients is addressed,while the inherent errors of UAV monitoring of mining surface subsidence are mitigated.The genetic algorithm(GA)-backpropagation(BP)neural network algorithm is combined with InSAR data to predict subsidence in collapsed areas.As observed,the GA-BP algorithm has the smallest residual under the same training samples.Therefore,the GA-BP neural network model can effectively predict surface subsidence in mining areas and can be used for subsequent subsidence prediction.
文摘Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and present hazards that can be essential to better predict risks in urbanised deltas.This paper aims to identify the effect of a long-term evolution of the prograded plain of the Tiber Delta in using current ground surface variations and geohistorical data.This study applies GIS(Geographic Information System)tools to LiDAR(Light Detection and Ranging)-derived DEM(Digital Elevation Model)data combined with stratigraphical data,aerial photography interpretation and old maps.The main outcome shows areas of subsidence are primarily located in the central part of the Tiber Delta.Lower heights at the river mouth are due to subsidence and specific lower morphologies associated with fast progradation phases,while similar low heights just north in the area of the international airport of Rome are due to subsidence alone.Subsidence under the airport is associated with the compaction of the silty clay infill of the Late Pleistocene Tiber Valley mostly deposited during the Holocene transgressive period.Only observed in the airport area,the presence of washover fans and the large extent of paleolagoons reveal the kind of risks that are increased by this subsidence.This study demonstrates that the densely urbanised central part of the Tiber Delta faces higher risks of marine submersion and coastal flooding considering ongoing relative sea level change.It also contributes to show the importance to better characterise past coastal morphologies to identify areas prone to subsidence.
基金supported by the National Natural Science Foundation of China(Grant Nos.5193400852374106+5 种基金5220416352404159)China Postdoctoral Science Foundation(Grant no.2024T171006)the Fundamental Research Funds for the Central Universities(Grant Nos.2024ZKPYNY042023ZKPYNY012023YQTD02)。
文摘Underground coal mining induces significant surface deformation and environmental damage,particularly in deeply buried mining areas with thin bedrock and thick alluvial layers.Based on the case study of the Zhaogu No.2 coal mine in Xinxiang City,Henan Province,China,this study employs a comprehensive research methodology,integrating field investigations,numerical simulations,and theoretical analyses,to explore the surface subsidence features at deeply buried mining areas with thin bedrock and thick alluvial layers,to reveal the effect of alluvial thickness on the surface subsidence characteristics.The findings indicate that the surface subsidence areas span 4.2 km2 with an advanced influence distance of 540 m.The rate of surface subsidence primarily depends on the panel's position and its advancing rate.Moreover,the thickness of the alluvial layer amplifies both the extent and magnitude of surface deformation.The displacement of overlying rock primarily exhibits a two-stage progression:the thin bedrock control stage and the alluvial control stage.In the thin bedrock control stage,surface subsidence initiates with relatively low subsidence values and amplitudes.Subsequently,in the alluvial control stage,surface subsidence accelerates,leading to a rapid increase in both subsidence values and amplitudes.These characteristics of rock formation displacement result in distinct phases of surface subsidence.Furthermore,the paper addresses the utilization of surface subsidence areas and proposes a method for calculating reservoir storage capacity in these areas.According to calculations,the storage capacity amounts to 1.05e7 m^(3).The research findings provide valuable insights into the surface subsidence laws in regions with similar geological conditions and practical implications for the management and utilization of subsided areas.
基金funded by the Key Research and Development Program of Shaanxi Province(No.2024SFYBXM-669)the National Natural Science Foundation of China(No.42271078)。
文摘0 INTRODUCTION Due to the rapid population growth and the accelerated urbanization process,the contradiction between the demand for expanding ground space and the limited available land scale is becoming increasingly prominent.China has implemented and completed several largescale land infilling and excavation projects(Figure 1),which have become the main way to increase land resources and expand construction land.
基金Project(2012BAB13B03)supported by the National Scientific and Technical Supporting Programs Funded of ChinaProject(41104011)supported by the National Natural Science Foundation of China+1 种基金Project(2013QNB07)supported by the Natural Science Funds for Young Scholar of China University of Mining and TechnologyProject(2012LWB32)supported by the Fundamental Research Funds for the Central Universities,China
文摘Based on the characteristics of strata movement of solid backfilling mining technology, the surface subsidence prediction method based on the equivalent mining height theory was proposed, and the parameters selection guideline of this method was also described. While comparing the parameters of caving mining with equivalent height, the subsidence efficient can be calculated according to the mining height and bulk factor of sagging zone and fracture zone, the tangent of main influence angle of solid backfilling mining is reduced by 0.2-0.5（while it cannot be less than 1.0）. For sake of safety, offset of the inflection point is set to zero, and other parameters, such as horizontal movement coefficient and main propagation angle are equal to the corresponding parameters of caving mining with equivalent height. In the last part, a case study of solid backfilling mining subsidence prediction was described. The results show the applicability of this method and the difference of the maximum subsidence point between the prediction and the observation is less than 5%.
