Soil erosion is a prominent environmental problem in karst regions.Exploring the spatiotemporal variability of soil erosion and the factors that influence soil erosion is of great significance for regional soil erosio...Soil erosion is a prominent environmental problem in karst regions.Exploring the spatiotemporal variability of soil erosion and the factors that influence soil erosion is of great significance for regional soil erosion prevention and control.However,the mechanisms influencing the characteristic features of the karst basins,such as bedrock exposure and lithology,still need to be further explored.This study used GIS technology,the Revised Universal Soil Loss Equation model,Getis–Ord Gi*,and partial least squares regression(PLSR)to identify the dominant factors influencing soil erosion and the spatiotemporal variability of soil erosion in 31 sub-basins of the Dabang River Basin(DRB),a typical karst area of Southwest China,from 2010 to 2020.The results indicated that soil erosion in the DRB from 2010 to 2020 was generally decreasing,the mean soil erosion in the DRB in 2010,2015 and 2020 was 18.46,16.51 and 15.29 t ha^(-1)a^(-1),respectively.During the study period,the area of slight erosion increased by 26.39%(706.54 km^(2)),while severe erosion enlarged by 26.36 km^(2).Spatially,the DRB was primarily affected by medium and slight soil erosion.The hot spot areas of soil erosion(key control areas)were mainly concentrated in the central and southern parts of the basin,decreasing each year,and the area of soil erosion hot pots has decreased from 43.22%to 20.60%.PLSR decoupling results show that elevation,bedrock exposure,land use type,interbedded limestone and clastic rock,and vegetation coverage were identified as the key variables affecting soil erosion,explaining 52.8%of soil erosion variability,with a high value of the Variable Importance on Projection(VIP)more than 1.These results can be used as a reference for comprehensive control of soil erosion and water loss in the basin.展开更多
The growth of society and population has led to a range of water pollution issues.Among these,non-point source pollution assessment and treatment pose a particular challenge due to its formation mechanism.This has bec...The growth of society and population has led to a range of water pollution issues.Among these,non-point source pollution assessment and treatment pose a particular challenge due to its formation mechanism.This has become a focal point and challenge in water pollution treatment research.The study area for this research was the Huanghou basin in Guizhou Province,southwest China.The land use type of the basin was analyzed using remote sensing technology,and water quality data was collected by distributing points throughout the basin,based on source-sink landscape theory.The distribution map of the basin’s source-sink landscape and the results of water quality data accurately and efficiently identified the areas with high risk of non-point source pollution in the western and southwestern residential and agricultural areas of the upper basin.Hence,a strategy of“increasing sinks and decreasing sources”was proposed.The strategy was implemented at both macro and micro levels to address non-point source pollution in the basin using ecological remediation techniques.The work to control karst rocky desertification should continue at a macro level.The rocky desertification area in the basin should gradually transform into grassland and forested land,while increasing the overall area of the sink landscape.Ecological restoration techniques,such as slope planting,riparian zone vegetation restoration,increasing plant abundance,and restoring aquatic plants,can effectively control non-point source pollution at the micro level.Compared to traditional control methods,this remediation strategy focuses on source and process control.It is more effective and does not require large-scale water pollution control projects,which can save a lot of environmental control funds and management costs.Therefore,it has greater research significance and application value.展开更多
Objective Complex geological factors have been constraining the oil and gas exploration in the Paleozoic strata of the Qaidam Basin,although there are high-quality hydrocarbon source rocks.One of the most important re...Objective Complex geological factors have been constraining the oil and gas exploration in the Paleozoic strata of the Qaidam Basin,although there are high-quality hydrocarbon source rocks.One of the most important reasons may be reservoir densification due to the multiple stages of destructive cementation,which has hindered our understanding of the Paleozoic petroleum enrichment rules in the Qaidam basin.In recent years,the展开更多
Long-term rainfall data are crucial for flood simulations and forecasting in karst regions.However,in karst areas,there is often a lack of suitable precipitation data available to build distributed hydrological models...Long-term rainfall data are crucial for flood simulations and forecasting in karst regions.However,in karst areas,there is often a lack of suitable precipitation data available to build distributed hydrological models to forecast karst floods.Quantitative precipitation forecasts(QPFs)and estimates(QPEs)could provide rational methods to acquire the available precipitation data for karst areas.Furthermore,coupling a physically based hydrological model with QPFs and QPEs could greatly enhance the performance and extend the lead time of flood forecasting in karst areas.This study served two main purposes.One purpose was to compare the performance of the Weather Research and Forecasting(WRF)QPFs with that of the Precipitation Estimations through Remotely Sensed Information based on the Artificial Neural Network-Cloud Classification System(PERSIANN-CCS)QPEs in rainfall forecasting in karst river basins.The other purpose was to test the feasibility and effective application of karst flood simulation and forecasting by coupling the WRF and PERSIANN models with the Karst-Liuxihe model.The rainfall forecasting results showed that the precipitation distributions of the 2 weather models were very similar to the observed rainfall results.However,the precipitation amounts forecasted by WRF QPF were larger than those measured by the rain gauges,while the quantities forecasted by the PERSIANN-CCS QPEs were smaller.A postprocessing algorithm was proposed in this paper to correct the rainfall estimates produced by the two weather models.The flood simulations achieved based on the postprocessed WRF QPF and PERSIANN-CCS QPEs coupled with the Karst-Liuxihe model were much improved over previous results.In particular,coupling the postprocessed WRF QPF with the Karst-Liuxihe model could greatly extend the lead time of flood forecasting,and a maximum lead time of 96 h is adequate for flood warnings and emergency responses,which is extremely important in flood simulations and forecasting.展开更多
Gas reservoir development of the Ordovician weathering crust in the Ordos Basin is closely controlled by the pre-Carboniferous paleogeomorphy.Previous studies show that the paleogeomorphy is high in the west and low i...Gas reservoir development of the Ordovician weathering crust in the Ordos Basin is closely controlled by the pre-Carboniferous paleogeomorphy.Previous studies show that the paleogeomorphy is high in the west and low in the east,and the karst highland,karst slope and karst basin are developed from west to east.With further exploration in recent years,many karst breccia that represent strong karstification,are found in the east area which previously is considered to be the Ordovician karst basin.Thus,it is necessary to revaluate controlling factors of karst paleogeomorphy development from a viewpoint of the dynamic paleogeomorphy evolution,to investigate the paleogeomorphy evolution of the Ordovician weathering crust in geological history and guide further research and prediction of development law of reservoir spaces.In order to reconstruct the paleogeomorphy of the weathering crust in the top of Ordovician in the east Ordos Basin,paleogeography,thickness of residual strata and paleokarst characteristics are well studied.The result shows that a wide range of paleokarst highland occurred in the central to east part of Ordos Basin in the early period,and the karst reservoir spaces were formed;but in the late period,the east part of the basin gradually evolved into the paleokarst basin,the current pre-Carboniferous paleogeomorphy was thus formed,and the dissolution reservoir spaces formed in the early period were mostly filled,accordingly the reservoirs were tight.However fracture networks formed by cave collapse connect intercrystalline pores of dolomite,therefore,the reservoirs can still be well preserved locally and are worthy targets for hydrocarbon exploration.展开更多
基金supported by National Natural Science Foundation of China(32060372,32360421)Guizhou Science and Technology Department(Qian Ke He Ji Chu ZK-[2023]Key 029Qiankehe Zhicheng[2021]Yiban462)。
文摘Soil erosion is a prominent environmental problem in karst regions.Exploring the spatiotemporal variability of soil erosion and the factors that influence soil erosion is of great significance for regional soil erosion prevention and control.However,the mechanisms influencing the characteristic features of the karst basins,such as bedrock exposure and lithology,still need to be further explored.This study used GIS technology,the Revised Universal Soil Loss Equation model,Getis–Ord Gi*,and partial least squares regression(PLSR)to identify the dominant factors influencing soil erosion and the spatiotemporal variability of soil erosion in 31 sub-basins of the Dabang River Basin(DRB),a typical karst area of Southwest China,from 2010 to 2020.The results indicated that soil erosion in the DRB from 2010 to 2020 was generally decreasing,the mean soil erosion in the DRB in 2010,2015 and 2020 was 18.46,16.51 and 15.29 t ha^(-1)a^(-1),respectively.During the study period,the area of slight erosion increased by 26.39%(706.54 km^(2)),while severe erosion enlarged by 26.36 km^(2).Spatially,the DRB was primarily affected by medium and slight soil erosion.The hot spot areas of soil erosion(key control areas)were mainly concentrated in the central and southern parts of the basin,decreasing each year,and the area of soil erosion hot pots has decreased from 43.22%to 20.60%.PLSR decoupling results show that elevation,bedrock exposure,land use type,interbedded limestone and clastic rock,and vegetation coverage were identified as the key variables affecting soil erosion,explaining 52.8%of soil erosion variability,with a high value of the Variable Importance on Projection(VIP)more than 1.These results can be used as a reference for comprehensive control of soil erosion and water loss in the basin.
文摘The growth of society and population has led to a range of water pollution issues.Among these,non-point source pollution assessment and treatment pose a particular challenge due to its formation mechanism.This has become a focal point and challenge in water pollution treatment research.The study area for this research was the Huanghou basin in Guizhou Province,southwest China.The land use type of the basin was analyzed using remote sensing technology,and water quality data was collected by distributing points throughout the basin,based on source-sink landscape theory.The distribution map of the basin’s source-sink landscape and the results of water quality data accurately and efficiently identified the areas with high risk of non-point source pollution in the western and southwestern residential and agricultural areas of the upper basin.Hence,a strategy of“increasing sinks and decreasing sources”was proposed.The strategy was implemented at both macro and micro levels to address non-point source pollution in the basin using ecological remediation techniques.The work to control karst rocky desertification should continue at a macro level.The rocky desertification area in the basin should gradually transform into grassland and forested land,while increasing the overall area of the sink landscape.Ecological restoration techniques,such as slope planting,riparian zone vegetation restoration,increasing plant abundance,and restoring aquatic plants,can effectively control non-point source pollution at the micro level.Compared to traditional control methods,this remediation strategy focuses on source and process control.It is more effective and does not require large-scale water pollution control projects,which can save a lot of environmental control funds and management costs.Therefore,it has greater research significance and application value.
基金supported by the National Natural Science Fund(grants No.41272159 and 41572099)Geological Survey Project of China Geological Survey (grant No.1212011120964)
文摘Objective Complex geological factors have been constraining the oil and gas exploration in the Paleozoic strata of the Qaidam Basin,although there are high-quality hydrocarbon source rocks.One of the most important reasons may be reservoir densification due to the multiple stages of destructive cementation,which has hindered our understanding of the Paleozoic petroleum enrichment rules in the Qaidam basin.In recent years,the
基金This study was supported by the National Science Foundation for Young Scientists of China(No.42101031)Chongqing Natural Science Foundation(No.cstc2021jcyj-msxm0007)+1 种基金the Open Project Program of Guangxi Key Science and Technology Innovation Base on Karst Dynamics(KDL&Guangxi 202009,KDL&Guangxi 202012)the National Natural Science Foundation of China(Grant No.41830648).
文摘Long-term rainfall data are crucial for flood simulations and forecasting in karst regions.However,in karst areas,there is often a lack of suitable precipitation data available to build distributed hydrological models to forecast karst floods.Quantitative precipitation forecasts(QPFs)and estimates(QPEs)could provide rational methods to acquire the available precipitation data for karst areas.Furthermore,coupling a physically based hydrological model with QPFs and QPEs could greatly enhance the performance and extend the lead time of flood forecasting in karst areas.This study served two main purposes.One purpose was to compare the performance of the Weather Research and Forecasting(WRF)QPFs with that of the Precipitation Estimations through Remotely Sensed Information based on the Artificial Neural Network-Cloud Classification System(PERSIANN-CCS)QPEs in rainfall forecasting in karst river basins.The other purpose was to test the feasibility and effective application of karst flood simulation and forecasting by coupling the WRF and PERSIANN models with the Karst-Liuxihe model.The rainfall forecasting results showed that the precipitation distributions of the 2 weather models were very similar to the observed rainfall results.However,the precipitation amounts forecasted by WRF QPF were larger than those measured by the rain gauges,while the quantities forecasted by the PERSIANN-CCS QPEs were smaller.A postprocessing algorithm was proposed in this paper to correct the rainfall estimates produced by the two weather models.The flood simulations achieved based on the postprocessed WRF QPF and PERSIANN-CCS QPEs coupled with the Karst-Liuxihe model were much improved over previous results.In particular,coupling the postprocessed WRF QPF with the Karst-Liuxihe model could greatly extend the lead time of flood forecasting,and a maximum lead time of 96 h is adequate for flood warnings and emergency responses,which is extremely important in flood simulations and forecasting.
基金The work was supported by the National Science and Technology Major Project of China(No.2016ZX05004,2016ZX05050).
文摘Gas reservoir development of the Ordovician weathering crust in the Ordos Basin is closely controlled by the pre-Carboniferous paleogeomorphy.Previous studies show that the paleogeomorphy is high in the west and low in the east,and the karst highland,karst slope and karst basin are developed from west to east.With further exploration in recent years,many karst breccia that represent strong karstification,are found in the east area which previously is considered to be the Ordovician karst basin.Thus,it is necessary to revaluate controlling factors of karst paleogeomorphy development from a viewpoint of the dynamic paleogeomorphy evolution,to investigate the paleogeomorphy evolution of the Ordovician weathering crust in geological history and guide further research and prediction of development law of reservoir spaces.In order to reconstruct the paleogeomorphy of the weathering crust in the top of Ordovician in the east Ordos Basin,paleogeography,thickness of residual strata and paleokarst characteristics are well studied.The result shows that a wide range of paleokarst highland occurred in the central to east part of Ordos Basin in the early period,and the karst reservoir spaces were formed;but in the late period,the east part of the basin gradually evolved into the paleokarst basin,the current pre-Carboniferous paleogeomorphy was thus formed,and the dissolution reservoir spaces formed in the early period were mostly filled,accordingly the reservoirs were tight.However fracture networks formed by cave collapse connect intercrystalline pores of dolomite,therefore,the reservoirs can still be well preserved locally and are worthy targets for hydrocarbon exploration.