To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river ...To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river types within Shandong Province:The mountainous Dawen River,the plain Tuhai River,and the artificial East Grand Canal.The DOM composition was analyzed using Ultraviolet-Visible(UV-Vis)absorption spectroscopy,Excitation-Emission Matrix(EEM)fluorescence spectroscopy,and parallel factor analysis(PARAFAC),while Principal Component Analysis(PCA)was employed to quantify the synergistic effects of natural processes and anthropogenic activities.Results revealed significant spatial heterogeneity in DOM composition and sources.The plain river exhibited the highest aromaticity(humic-like components:43.3%)due to long-term agricultural non-point source inputs and urban wastewater discharge.The mountain stream,shaped by complex terrain and relatively intact ecosystems,was dominated by autochthonous DOM derived from microbial metabolism,with higher Fluorescence Index(FI=2.12)and biological index(BIX=1.35)than other river types.The artificial canal retained protein-like components(64.2%),largely attributed to winter hydrological stagnation and disturbances from shipping activities.Further analysis demonstrated that geographical settings(e.g.,mountain terrain)and anthropogenic activities(e.g.,agriculture,shipping)jointly regulated DOM composition by altering the balance between input and transformation processes.Integrated fluorescence parameters and PCA results suggested differentiated management strategies:protecting ecological integrity in mountain streams to sustain selfpurification,enhancing non-point source interception in plain rivers,and mitigating shipping pollution in canals.This study systematically reveals the natural-anthropogenic coupling mechanisms driving DOM dynamics in northern China rivers,providing critical insights for precision water environment management at the watershed scale.展开更多
To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrat...To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrating groundwater nitrate vulnerability assessment and Nitrate Vulnerable Zones(NVZs)delineation through optimization of hydrogeological parameters.Based on detailed hydrogeological and hydrochemical investigations,the DITAPH model was applied in the plain areas of Quanzhou to evaluate its applicability.The model selected hydrogeological parameters(depth of groundwater,lithology of the vadose zone,topographic slope,aquifer water yield property),one climatic parameter(precipitation),and two anthropogenic parameters(land use type and population density)as assessment indicators.The results of the groundwater nitrate vulnerability assessment showed that the low,relatively low,relatively high,and high groundwater nitrate vulnerability zones in the study area accounted for 5.96%,35.44%,53.74%and 4.86%of the total area,respectively.Groundwater nitrate vulnerability was most strongly influenced by human activities,followed by groundwater depth and topographic slope.The high vulnerability zone is mainly affected by domestic and industrial wastewater,whereas the relatively high groundwater nitrate vulnerability zone is primarily influenced by agricultural activities.Validation of the DITAPH model revealed a significant positive correlation between the DITAPH index(DI)and nitrate concentration(ρ(NO3−)).The results of the NVZs delineated by the DITAPH model are reliable and can serve as a tool for water resource management planning,guiding the development of targeted measures in the NVZs to prevent groundwater contamination.展开更多
China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and t...China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area.展开更多
The changes of development and utilization of karst groundwater in Sangu Spring Basin have made the original groundwater resource evaluation unable to meet the needs of future economic development.Based on analysis of...The changes of development and utilization of karst groundwater in Sangu Spring Basin have made the original groundwater resource evaluation unable to meet the needs of future economic development.Based on analysis of existing data,combined with the characteristics of supplement,runoff and draining of regional karst groundwater,the Visual Modelflow software was used to build a numerical simulation model of Sangu spring Basin.The amount of karst groundwater resource and groundwater environment of the Basin were evaluated under different exploitation schemes,and the changes of karst groundwater environment in the future ten years were also predicted.The fitting error which is less than 0.5 m between the calculated value and measured value of the water level in the fitted borehole accounts for 93%.For the lithologically and structurally complex Sangu Spring Basin,the fitting effect of numerical simulation model was ideal.On the basis of the current mining amount of 111.80 million m3/a,the total redistributed exploited amount in the spring region was 61.79 million m3/a.Under the condition that the quantity of recoverable resources reached 173.59 million m3/a and under different precipitation schemes,all constraint conditions were satisfied,such as regional water level drawdown,maximum allowable water level drawdown in every simulated water source area and the flow rate of Guobi Spring.The results will provide a scientific basis for the rational development and utilization of karst groundwater in Sangu Spring Basin.展开更多
The Wenchuan earthquake in 2008 and geo-hazards triggered by the earthquake caused large injuries and deaths as well as destructive damage for infrastructures like construction, traffic and electricity. It is urgent t...The Wenchuan earthquake in 2008 and geo-hazards triggered by the earthquake caused large injuries and deaths as well as destructive damage for infrastructures like construction, traffic and electricity. It is urgent to select relatively secure areas for townships and cities constructed in high mountainous regions with high magnitude earthquakes. This paper presents the basic thoughts, evaluation indices and evaluation methods of geological security evaluation, water and land resources security demonstration and integrated assessments of geo-environmental suitability for reconstruction in alp and ravine with high magnitude earthquakes, which are applied in the worst-hit areas （12 counties）. The integrated assessment shows that： （1） located in the Longmenshan fault zone, the evaluated area is of poor regional crust stability, in which the unstable and second unstable areas account for 79% of the total; （2） the geo-hazards susceptibility is high in the evaluation area. The spots of geo-hazards triggered by earthquake are mainly distributed along the active fault zone with higher distribution in the moderate and high mountains area, in which the areas of high and moderate susceptibility zoning accounts for 40.1% of the total; （3） geological security is poor in the evaluated area, in which the area of the unsuitable construction occupies 73.1%, whereas in the suitable construction area, the areas of geological security, second security and insecurity zoning account for 8.3 %, 9.3% and 9.3 % of the evaluated area respectively; （4） geo-environmentai suitability is poor in the evaluated area, in which the areas of suitability and basic suitability zoning account for 3.5% and 7.3% of the whole evaluation area.展开更多
Xining,a river valley city in China’s arid region,serves as an important industrial hub with a fragile ecological environment.While groundwater heavy metal pollution in this area has drawn increasing concern,the sour...Xining,a river valley city in China’s arid region,serves as an important industrial hub with a fragile ecological environment.While groundwater heavy metal pollution in this area has drawn increasing concern,the sources and associated human health risks remain inadequately understood.This study analyzed 144 shallow groundwater samples from urban Xining for 14 heavy metals(Fe,Al,B,Mn,Ba,Zn,Pb,Cr^(6+),Ni,Cu,Co,Sb,Cd,and As)using the Nemerow comprehensive pollution index,correlation analysis,and the USEPA health risk assessment model.Results identified Fe,Al,B,Mn,Ba,Pb,Cd,and As as the primary pollutants,especially concentrated in river valley plains.These contaminants primarily originate from natural sedimentary conditions and human activities such as industrial and agricultural development.The pollution indices for Al,Pb,Mn,and Fe exceeded clean water thresholds,indicating serious contamination and the need for enhanced regulation.Health risk assessments revealed that children face greater exposure risks than adults,with arsenic and nickel being the main contributors to carcinogenic risk.Sensitivity analysis further showed that As,Fe,and Cd posed the greatest non-carcinogenic and carcinogenic risks,particularly in human-impacted areas such as the Nanchuan and Beichuan valleys and Ganhegou.These findings provide essential insights for groundwater safety management in plateau river valley cities and similar vulnerable regions.展开更多
Tai'an city,located in Shandong Province,China,is rich in geothermal resources,characterized by shallow burial,high water temperature,and abundant water supply,making them high value for exploitation.However,corro...Tai'an city,located in Shandong Province,China,is rich in geothermal resources,characterized by shallow burial,high water temperature,and abundant water supply,making them high value for exploitation.However,corrosion and scaling are main challenges that hinder the widespread application and effective utilization of geothermal energy.This study focuses on the typical geothermal fields in Tai'an,employing qualitative evaluations of the geochemical saturation index with temperature,combined with the corrosion coefficient,Ryznar index,boiler scale,and hard scale assessment,to predict corrosion and scaling trends in the geothermal water of the study area.The results show that the hydrochemical types of geothermal water in the study area are predominantly Na-Ca-SO^(4)and Ca-Na-SO_(4)-HCO_(3),with the water being weakly alkaline.Simulations of saturation index changes with temperature reveal that calcium carbonate scaling is dominant scaling type in the area,with no evidence of calcium sulfate scaling.In the Daiyue Qiaogou geothermal field,the water exhibited corrosive bubble water properties,moderate calcium carbonate scaling,and abundant boiler scaling.Feicheng Anjiazhuang geothermal field showed non-corrosive bubble water,moderate calcium carbonate scaling,and significant boiler scaling.The Daidao'an geothermal field presented corrosive semi-bubble water,moderate calcium carbonate scaling,and abundant boiler scaling.The findings provide a foundation for the efficient exploitation of geothermal resources in the region.Implementing anti-corrosion and scale prevention measures can significantly enhance the utilization of geothermal energy.展开更多
Xiong'an New Area boasts abundant geothermal resources,with widespread Jixianian geother-mal reservoirs serving as key targets for exploration and development.Zoning geothermal resources helps characterize their d...Xiong'an New Area boasts abundant geothermal resources,with widespread Jixianian geother-mal reservoirs serving as key targets for exploration and development.Zoning geothermal resources helps characterize their distribution and attributes,offering critical guidance for their sustainable exploitation and utilization.This study integrates data from drilling and production tests across 21 geothermal wells to analyze the Jixianian strata,including depth,thickness,temperature,single-well water yield,Groundwater Level Depth(GWD),and Total Dissolved Solids(TDS).Employing fuzzy mathematics,a zoning analysis was performed,yielding quantitative evaluation scores and delineating favorable zones for development.Key findings include:(1)Geothermal reservoirs in the Rongcheng and Niutuozhen uplifts exhibit shallow burial depths,substantial thicknesses,high productivity,and relatively low temperatures,making them highly suitable for large-scale geothermal exploitation;(2)Zones with high resource potential but uncertain conditions require further exploration to mitigate development risks;(3)Areas near the Rongcheng fault or Jixianian strata buried deeper than 4,000 m are recommended for deferred exploitation;(4)Comprehensive evaluation reveals that the Jixianian carbonate geothermal reservoirs in Xiong'an New Area manifest 168 geothermal resources of 5,370.31×10 J,geothermal fluid reserves of 101.17×10 m3,and recoverable fluid 4 reserves of 93.41×10 m3/d under balanced extraction and reinjection.Recoverable geothermal heat 164 amounts to 9.36×10 J/a,equivalent to 319.4×10 t/a of standard coal.This study provides valuable insights into the exploration and sustainable exploitation of deep geothermal reservoirs in Xiong'an New Area,enhancing resource utilization and contributing to the development of a green and sustainable Xiong'an New Area.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
This study,based on Artificial Neural Network(ANN)technology,develops a quantitative prediction model for the unit water flow rate of the Quaternary strata in the Shijiazhuang-Hebei Plain area.The study area extends f...This study,based on Artificial Neural Network(ANN)technology,develops a quantitative prediction model for the unit water flow rate of the Quaternary strata in the Shijiazhuang-Hebei Plain area.The study area extends from the piedmont region of Shijiazhuang,at the eastern foothills of the Taihang Mountains,to the hinterland area of Hengshui within the plain in Hebei Province section of the North China Plain.The hydrological and exploration boreholes selected for modeling are primarily located in the south-eastern part of Shijiazhuang urban area—the southern region of Xinji County—north of Hengshui City near the Shenzhou County area.By employing the Induced Polarization method(IP)and Vertical Electrical Sounding(VES),apparent resistivity(ρS),apparent polarization rate(ηS),half-decay time(Th),and decay degree(D)were obtained as initial input parameters.These were combined with the measured water flow rates from borehole pumping tests to build the training sample set.To address the prevalent issue of high-salinity interference in the study area,multiple regression analysis revealed that when the inverted resistiv-ity(ρ)is less than 5Ω·m and the inverted polarization rate(η)is greater than 8%,the contribution of groundwater salinity to the resistivity parameter reaches 42%±6%.Based on this,a comprehensive parame-ter T"=ρ*H/ρ'was established,whereρis the aquifer resistivity,ρ'is the aquitard resistivity,and H is the aquifer thickness.The resistivity ratio effectively eliminates the coupling effect between electrical parame-ters and salinity.The input neurons of the improved model were adjusted to a four-parameter system consisting of decay time(Th),decay degree(D),deviation degree(σ),and the comprehensive parameter(T").Experiments showed that the prediction error of the model on the validation set was reduced from the original model's 5%-10%to 0.9%-5%.The introduction of the T"parameter reduced the prediction error in high salinity areas(Cl->500 mg/L)to within 7%.The study confirms that the composite parameter T"based on geophysical inversion parameters can effectively characterize the coupling features of aquifer thickness and water quality.Even with a small sample size,through algorithm optimization,data augmentation,and model structural improvements,it is entirely possible to effectively enhance prediction accuracy and gener-alization ability,providing a new parameterization method for the quantitative evaluation of Quaternary pore water in plain areas.展开更多
Developing a rapid and precise method for trace element analysis in geothermal water is crucial due to its high total dissolved solids and salinity,which can impact element determination.In this study,we optimized the...Developing a rapid and precise method for trace element analysis in geothermal water is crucial due to its high total dissolved solids and salinity,which can impact element determination.In this study,we optimized the determination of ferrum,manganese,strontium and barium in geothermal water samples collected from different regions.A matrix matching method was established for accurate quantification using Inductively Coupled Plasma Optical Emission Spectroscopy(ICP-OES).Instrumental conditions and experimental parameters were optimized,and the influence of storage medium and storage duration on measurement accuracy were evaluated.The results demonstrated that storing geothermal water samples in 1%nitric acid had no significant impact on measurement results over an eight-week period.Calibration curve correlation coefficients exceeded 0.9998 for all target elements.The detection limits of this method ranged from 0.0002 mg/L to 0.0031 mg/L,with Relative Standard Deviations(RSD)were 0.07%–2.33%,and spike recovery rates were from 96.8%to 103.2%.The obtained data were consistent with results from the standard addition method and dilution method,demonstrating the reliability of this approach.This method offers low detection limits,high precision and excellent recovery rate,providing a robust reference for the accurate determination of ferrum,manganese,strontium and barium in geothermal water,thereby laying a solid foundation for the development and utilization of geothermal resources.展开更多
The groundwater in the research area is characterized by alkalescence,generally over-high EC value,and relatively low dissolved oxygen and oxidation-reduction potential.The pollution is presented by abnormal acid-base...The groundwater in the research area is characterized by alkalescence,generally over-high EC value,and relatively low dissolved oxygen and oxidation-reduction potential.The pollution is presented by abnormal acid-base,dissolved oxygen reduction,and conductivity rise.The overall situation of groundwater chemical field is controlled by natural conditions,the hydrochemical type has obvious zoning feature and changes from single type to multiple types from the river bank of the Yellow River to both sides,and the local abnormality is closely related to the intensity of human activities.The pollution scope and degree of inorganic toxicological indexes and organic indexes are strongly correlated with land utilization type,pollution source distribution,urbanization,and pollutant disposal of the city,the pollution in the petrochemical industrial area is the most serious,and the organic pollution tends to escalate and diffuse to the downstream.展开更多
A much improved understanding of how farmyard manure application may affect carbonate rock dissolution is needed in order to predict possible feedbacks between the rock carbon cycle and the global climate system. Two ...A much improved understanding of how farmyard manure application may affect carbonate rock dissolution is needed in order to predict possible feedbacks between the rock carbon cycle and the global climate system. Two carbonate mineral rock tablets; dolomite and limestone were buried at six depths between 0 and 110 cm in a soil typical of the subtropical karst area in Guiyang City, Guizhou Province. The extent of tablet dissolution, soil CO2, soil p H, soil water content, soil mineral and chemical composition, and chemical composition of soil water were tested in order to assess the degree of dissolution under manure application over the course of one year. The results show that manure addition decreases the dissolution rate of carbonate rocks; limestone and dolomite by between 11.7%-116.9% and 25.0%-65.69% respectively, with the dissolution rate of limestone consistently exceeding that of dolomite under the same conditions. Our data indicates that the rate of pedogenesis of the dolomite and limestone rocks is decreased as much as 35.77% and 59.41% respectively, as a result of manure application. Moreover, the results suggest that manure application accelerated the generation of soil CO2, with soil CO2 concentration increasing on average by 93.94%, and the CO2 flux increasing by 67.64% compared with the control profile. Finally, the data also indicates that manure decreases CO2 uptake by dissolution of carbonate rocks by 25.50%-39.45% on a Guiyang city scale. The counteraction of the CO2 sink contributed by karst water due to farmyard manure utilization in general karst area（both dolomite and limestone） however was 59.41%-62.72%, indicating the application of manure successfully reduces both dissolution and CO2 release to the atmosphere.展开更多
Dilution and attenuation factor (DAF) has a major influence on soil-to-groundwater screening level calculation for protection of contaminant migration from soil into groundwater at solid waste management units (SWMUs)...Dilution and attenuation factor (DAF) has a major influence on soil-to-groundwater screening level calculation for protection of contaminant migration from soil into groundwater at solid waste management units (SWMUs). Risk assessment guidance prepared by U.S. Environmental Protection Agency for site investigation and remediation suggests a default DAF of 20. If the base assumptions included in the default DAF are recognized to be not representative of site conditions at a SWMU, calculation of site-specific DAF is recommended when sufficient data are collected to justify using a different DAF value for development of soil screening levels. Commonly used methods of calculating DAF include analytical and numerical simulations that often require too many parameters to be obtained in practice. This paper proposes a probability method to develop site-specific DAF. The approach uses data that are readily available through field reconnaissance and site-specific investigation. A case study is presented in which the probability method was applied to an actual SWMU, and the calculated DAF is compared with that calculated from a dilution method. The probability-based DAF is 67 at 90% probability percentile, which is comparable to the dilution-based DAF of 76. Based on the calculated site-specific DAFs, SSLs could be developed for the contaminants of potential concern and used for evaluation of migration pathways from a contamination source through soil to groundwater. .展开更多
A multi-isotope approach and mixing model were combined to identify spatial and seasonal variations of sources,and their proportional contribution to nitrate in the Hutuo River alluvial-pluvial fan region.The results ...A multi-isotope approach and mixing model were combined to identify spatial and seasonal variations of sources,and their proportional contribution to nitrate in the Hutuo River alluvial-pluvial fan region.The results showed that the NO3- concentration was significantly higher in the Hutuo River valley plain(178.7 mg/L) region than that in the upper and central pluvial fans of the Hutuo River(82.1 mg/L and 71.0 mg/L,respectively)and in the river(17.0 mg/L).Different land use types had no significant effect on the groundwater nitrate concentration.Based on a multi-isotope approach,we confirmed that the main sources of groundwater nitrate in different land use areas were domestic sewage and manure,followed by soil nitrogen,ammonia fertilizer,nitrate fertilizer and rainwater,and there were no significant spatial or seasonal variations.Combining δ^15N-NO3,δ^18O-NO3- and δ^37Cl results can increase the accuracy of traceability.Nitrification could be the most important nitrogen migration and transformation process,and denitrification did not significantly affected the isotopic composition of the nitrate.The SIAR model outputs revealed that the main nitrate pollution sources in groundwater and river water were domestic sewage and manure,accounting for 55.9%-61.0% and 22.6%(dry season),50.3%-60.4% and 34.1%(transition season),42.7%-47.6% and 35.6%(wet season 2016) and 45.9%-46.7% and 38.4%(wet season 2017),respectively.This work suggests that the random discharge and disposal of domestic sewage and manure should be the first target for control in order to prevent further nitrate contamination of the water environment.展开更多
Understanding the controlling factor of groundwater quality can enhance promoting sustainable development of groundwater resources. To this end, multivariate statistical analysis（MA） and hydrochemical analysis were ...Understanding the controlling factor of groundwater quality can enhance promoting sustainable development of groundwater resources. To this end, multivariate statistical analysis（MA） and hydrochemical analysis were introduced in this work. The results indicate that the canonical discriminant function with 7 parameters was established using the discriminant analysis（DA） method, which can afford 100% correct assignation according to the 3 different clusters（good water（GW）, poor water（PW）, and very poor water（VPW）） obtained from cluster analysis（CA）. According to factor analysis（FA）, 8 factors were extracted from 25 hydrochemical elements and account for 80.897% of the total data variance, suggesting that groundwater with higher concentrations of sodium, calcium, magnesium, chloride, and sulfate in southeastern study area are mainly affected by the natural process; the higher level of arsenic and chromium in groundwater extracted from northwestern part of study area are derived by industrial activities; domestic and agriculture sewage have important contribution to copper, iron, iodine, and phosphate in the northern study area. Therefore, this work can help identify the main controlling factor of groundwater quality in North China plain so as to make better and more informed decisions about how to achieve groundwater resources sustainable development.展开更多
We present the first systematic hydrogeological analysis to grain insights on the evolution of the Gonghe Basin in North China. Two hundred and forty seven water samples were collected from the Gonghe East Basin, Gong...We present the first systematic hydrogeological analysis to grain insights on the evolution of the Gonghe Basin in North China. Two hundred and forty seven water samples were collected from the Gonghe East Basin, Gonghe West Basin and Chaka Basin. The three groundwater systems of Gonghe Basin from west to east display different geochemical signatures. Based on Na/Cl ratios and Langelier-Ludwig diagram, it is inferred that the groundwater recharge potential of the Gonghe East Basin is much prosperous than the other areas. The renewability of the aquifers in alluvial-proluvial fan of Wahonghe and Gonghe East Basin margin is much faster than in the other basins. The groundwater quality in Chaka Salt Lake,Shazhuyu and Qiabuqia River Valley plains is low due to strong evaporation and cation exchange. The groundwater quality of the phreatic aquifers in the Qiabuqia River Valley plain is further deteriorated by mixing of high-arsenic and high-mineralization water from the deep fault structures.展开更多
Lithium separation technique for three reference materials has been established together with precise determination of lithium isotope using a Neptune multi collector-inductively coupled plasma mass spectrometry （MC-...Lithium separation technique for three reference materials has been established together with precise determination of lithium isotope using a Neptune multi collector-inductively coupled plasma mass spectrometry （MC-ICP-MS）. The solutions of lithium element standard reference materials, potassium, calcium, sodium, magnesium and iron single element, were used to evaluate analytical methods applied. Three separate stages of ion-exchange chromatography were carried out using organic cation-exchange resin （AG 50W-X8）. Lithium was enriched for the three stages using different eluants, which are 2.8 M HCl, 0.15 M HCl and 0.5 M HCl in 30% ethanol, respectively. The columns for the first and second stages are made of polypropylene, and those for the third stage are made of quartz. Total reagent volume for the entire chemical process was 35 mL for three reference materials. The recovery yielded for the three stages is 98.9-101.2% with an average of 100.0%, 97.6-101.9% with an average of 99.9%, and 99.8-103.3% with an average of 100.6%, respectively. The precision of this technique is conservatively estimated to be ±0.72-1.04‰ （2σ population）, which is similar to the precision obtained by different authors in different laboratories with MC-ICP-MS. The δ7 Li values （ 7 Li/ 6 Li relative to the IRMM-016 standard） determined for andesite （AGV-2） and basalt （BHVO-2） are 5.68‰ （n=18）, 4.33‰ （n=18）, respectively. The δ7 Li value （ 7Li/6Li relative to the L-SVEC standard） determined for IRMM-016 is -0.01‰ （n=15）. All these analytical results are in good agreement with those previously reported. In addition, the results for the same kinds of samples analyzed at the MLR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, are consistent with those obtained at the Plasma Laboratory, University of Maryland, within analytical uncertainty. According to these experiment results, it is concluded that this proposed procedure is a suitable method for determining the lithium isotopic composition of natural samples.展开更多
Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the stu...Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound pollution.The root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dominated by Cd and Ni to varying degrees, especially wheat. As indicated by the health risk assessment results, the intake of maize in the study area does not pose significant human health risks;however, Cu has high risks to human health, and the compound heavy metal pollution caused by the intake of wheat in the study area poses risks to the health of both adults and children. Overall, the soils and crops in the study area suffer a high degree of heavy metal pollution, for which mining activities may be the main reason.展开更多
Landslide is a serious natural disaster next only to earthquake and flood,which will cause a great threat to people’s lives and property safety.The traditional research of landslide disaster based on experience-drive...Landslide is a serious natural disaster next only to earthquake and flood,which will cause a great threat to people’s lives and property safety.The traditional research of landslide disaster based on experience-driven or statistical model and its assessment results are subjective,difficult to quantify,and no pertinence.As a new research method for landslide susceptibility assessment,machine learning can greatly improve the landslide susceptibility model’s accuracy by constructing statistical models.Taking Western Henan for example,the study selected 16 landslide influencing factors such as topography,geological environment,hydrological conditions,and human activities,and 11 landslide factors with the most significant influence on the landslide were selected by the recursive feature elimination(RFE)method.Five machine learning methods[Support Vector Machines(SVM),Logistic Regression(LR),Random Forest(RF),Extreme Gradient Boosting(XGBoost),and Linear Discriminant Analysis(LDA)]were used to construct the spatial distribution model of landslide susceptibility.The models were evaluated by the receiver operating characteristic curve and statistical index.After analysis and comparison,the XGBoost model(AUC 0.8759)performed the best and was suitable for dealing with regression problems.The model had a high adaptability to landslide data.According to the landslide susceptibility map of the five models,the overall distribution can be observed.The extremely high and high susceptibility areas are distributed in the Funiu Mountain range in the southwest,the Xiaoshan Mountain range in the west,and the Yellow River Basin in the north.These areas have large terrain fluctuations,complicated geological structural environments and frequent human engineering activities.The extremely high and highly prone areas were 12043.3 km^(2)and 3087.45 km^(2),accounting for 47.61%and 12.20%of the total area of the study area,respectively.Our study reflects the distribution of landslide susceptibility in western Henan Province,which provides a scientific basis for regional disaster warning,prediction,and resource protection.The study has important practical significance for subsequent landslide disaster management.展开更多
基金supported by the National Natural Science Foundation(42472325)the Fundamental Research Funds of Chinese Academy of Geological Science(SK202103).
文摘To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river types within Shandong Province:The mountainous Dawen River,the plain Tuhai River,and the artificial East Grand Canal.The DOM composition was analyzed using Ultraviolet-Visible(UV-Vis)absorption spectroscopy,Excitation-Emission Matrix(EEM)fluorescence spectroscopy,and parallel factor analysis(PARAFAC),while Principal Component Analysis(PCA)was employed to quantify the synergistic effects of natural processes and anthropogenic activities.Results revealed significant spatial heterogeneity in DOM composition and sources.The plain river exhibited the highest aromaticity(humic-like components:43.3%)due to long-term agricultural non-point source inputs and urban wastewater discharge.The mountain stream,shaped by complex terrain and relatively intact ecosystems,was dominated by autochthonous DOM derived from microbial metabolism,with higher Fluorescence Index(FI=2.12)and biological index(BIX=1.35)than other river types.The artificial canal retained protein-like components(64.2%),largely attributed to winter hydrological stagnation and disturbances from shipping activities.Further analysis demonstrated that geographical settings(e.g.,mountain terrain)and anthropogenic activities(e.g.,agriculture,shipping)jointly regulated DOM composition by altering the balance between input and transformation processes.Integrated fluorescence parameters and PCA results suggested differentiated management strategies:protecting ecological integrity in mountain streams to sustain selfpurification,enhancing non-point source interception in plain rivers,and mitigating shipping pollution in canals.This study systematically reveals the natural-anthropogenic coupling mechanisms driving DOM dynamics in northern China rivers,providing critical insights for precision water environment management at the watershed scale.
基金supported by the National Key Research and Development Program of China(No.2022YFF1301301)the Natural Science Foundation of Xiamen Municipality(No.3502Z202472047)the Geological Survey Program of China Geological Survey(DD20190303).
文摘To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrating groundwater nitrate vulnerability assessment and Nitrate Vulnerable Zones(NVZs)delineation through optimization of hydrogeological parameters.Based on detailed hydrogeological and hydrochemical investigations,the DITAPH model was applied in the plain areas of Quanzhou to evaluate its applicability.The model selected hydrogeological parameters(depth of groundwater,lithology of the vadose zone,topographic slope,aquifer water yield property),one climatic parameter(precipitation),and two anthropogenic parameters(land use type and population density)as assessment indicators.The results of the groundwater nitrate vulnerability assessment showed that the low,relatively low,relatively high,and high groundwater nitrate vulnerability zones in the study area accounted for 5.96%,35.44%,53.74%and 4.86%of the total area,respectively.Groundwater nitrate vulnerability was most strongly influenced by human activities,followed by groundwater depth and topographic slope.The high vulnerability zone is mainly affected by domestic and industrial wastewater,whereas the relatively high groundwater nitrate vulnerability zone is primarily influenced by agricultural activities.Validation of the DITAPH model revealed a significant positive correlation between the DITAPH index(DI)and nitrate concentration(ρ(NO3−)).The results of the NVZs delineated by the DITAPH model are reliable and can serve as a tool for water resource management planning,guiding the development of targeted measures in the NVZs to prevent groundwater contamination.
基金supported by two projects initialed China Geological Survey: “Evaluation on Soil and Water Quality and Geological Survey in Xiong’an New Area (DD20189122)” and “Monitoring and Evaluation on Carrying Capacity of Resource and Environment in BeijingTianjin-Hebei Coordinated Development Zone and Xiong’an New Area (DD20221727)”
文摘China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area.
基金This work was supported by the Fundamental Research Funds for the Chinese Academy of Geosciences(No.JYYWF20180401)the China Geological Survey project(No.DD20160296,DD20201123).
文摘The changes of development and utilization of karst groundwater in Sangu Spring Basin have made the original groundwater resource evaluation unable to meet the needs of future economic development.Based on analysis of existing data,combined with the characteristics of supplement,runoff and draining of regional karst groundwater,the Visual Modelflow software was used to build a numerical simulation model of Sangu spring Basin.The amount of karst groundwater resource and groundwater environment of the Basin were evaluated under different exploitation schemes,and the changes of karst groundwater environment in the future ten years were also predicted.The fitting error which is less than 0.5 m between the calculated value and measured value of the water level in the fitted borehole accounts for 93%.For the lithologically and structurally complex Sangu Spring Basin,the fitting effect of numerical simulation model was ideal.On the basis of the current mining amount of 111.80 million m3/a,the total redistributed exploited amount in the spring region was 61.79 million m3/a.Under the condition that the quantity of recoverable resources reached 173.59 million m3/a and under different precipitation schemes,all constraint conditions were satisfied,such as regional water level drawdown,maximum allowable water level drawdown in every simulated water source area and the flow rate of Guobi Spring.The results will provide a scientific basis for the rational development and utilization of karst groundwater in Sangu Spring Basin.
文摘The Wenchuan earthquake in 2008 and geo-hazards triggered by the earthquake caused large injuries and deaths as well as destructive damage for infrastructures like construction, traffic and electricity. It is urgent to select relatively secure areas for townships and cities constructed in high mountainous regions with high magnitude earthquakes. This paper presents the basic thoughts, evaluation indices and evaluation methods of geological security evaluation, water and land resources security demonstration and integrated assessments of geo-environmental suitability for reconstruction in alp and ravine with high magnitude earthquakes, which are applied in the worst-hit areas （12 counties）. The integrated assessment shows that： （1） located in the Longmenshan fault zone, the evaluated area is of poor regional crust stability, in which the unstable and second unstable areas account for 79% of the total; （2） the geo-hazards susceptibility is high in the evaluation area. The spots of geo-hazards triggered by earthquake are mainly distributed along the active fault zone with higher distribution in the moderate and high mountains area, in which the areas of high and moderate susceptibility zoning accounts for 40.1% of the total; （3） geological security is poor in the evaluated area, in which the area of the unsuitable construction occupies 73.1%, whereas in the suitable construction area, the areas of geological security, second security and insecurity zoning account for 8.3 %, 9.3% and 9.3 % of the evaluated area respectively; （4） geo-environmentai suitability is poor in the evaluated area, in which the areas of suitability and basic suitability zoning account for 3.5% and 7.3% of the whole evaluation area.
基金supported by the projects of the Geological Survey(DD20240501104,DD20230422).
文摘Xining,a river valley city in China’s arid region,serves as an important industrial hub with a fragile ecological environment.While groundwater heavy metal pollution in this area has drawn increasing concern,the sources and associated human health risks remain inadequately understood.This study analyzed 144 shallow groundwater samples from urban Xining for 14 heavy metals(Fe,Al,B,Mn,Ba,Zn,Pb,Cr^(6+),Ni,Cu,Co,Sb,Cd,and As)using the Nemerow comprehensive pollution index,correlation analysis,and the USEPA health risk assessment model.Results identified Fe,Al,B,Mn,Ba,Pb,Cd,and As as the primary pollutants,especially concentrated in river valley plains.These contaminants primarily originate from natural sedimentary conditions and human activities such as industrial and agricultural development.The pollution indices for Al,Pb,Mn,and Fe exceeded clean water thresholds,indicating serious contamination and the need for enhanced regulation.Health risk assessments revealed that children face greater exposure risks than adults,with arsenic and nickel being the main contributors to carcinogenic risk.Sensitivity analysis further showed that As,Fe,and Cd posed the greatest non-carcinogenic and carcinogenic risks,particularly in human-impacted areas such as the Nanchuan and Beichuan valleys and Ganhegou.These findings provide essential insights for groundwater safety management in plateau river valley cities and similar vulnerable regions.
基金funded by the Key R&D Program of Henan,China(No.241111321000)China Geological Survey Program(DD20221676).
文摘Tai'an city,located in Shandong Province,China,is rich in geothermal resources,characterized by shallow burial,high water temperature,and abundant water supply,making them high value for exploitation.However,corrosion and scaling are main challenges that hinder the widespread application and effective utilization of geothermal energy.This study focuses on the typical geothermal fields in Tai'an,employing qualitative evaluations of the geochemical saturation index with temperature,combined with the corrosion coefficient,Ryznar index,boiler scale,and hard scale assessment,to predict corrosion and scaling trends in the geothermal water of the study area.The results show that the hydrochemical types of geothermal water in the study area are predominantly Na-Ca-SO^(4)and Ca-Na-SO_(4)-HCO_(3),with the water being weakly alkaline.Simulations of saturation index changes with temperature reveal that calcium carbonate scaling is dominant scaling type in the area,with no evidence of calcium sulfate scaling.In the Daiyue Qiaogou geothermal field,the water exhibited corrosive bubble water properties,moderate calcium carbonate scaling,and abundant boiler scaling.Feicheng Anjiazhuang geothermal field showed non-corrosive bubble water,moderate calcium carbonate scaling,and significant boiler scaling.The Daidao'an geothermal field presented corrosive semi-bubble water,moderate calcium carbonate scaling,and abundant boiler scaling.The findings provide a foundation for the efficient exploitation of geothermal resources in the region.Implementing anti-corrosion and scale prevention measures can significantly enhance the utilization of geothermal energy.
基金funded by the Study on enhanced heat transfer mechanism of low-permeability carbonate rocks under in-situ conditions under Grant number YK202305the National Natural Science Foundation of China under Grant number 42272350the Geothermal Survey Project of the China Geological Survey under Grant number DD20221676.
文摘Xiong'an New Area boasts abundant geothermal resources,with widespread Jixianian geother-mal reservoirs serving as key targets for exploration and development.Zoning geothermal resources helps characterize their distribution and attributes,offering critical guidance for their sustainable exploitation and utilization.This study integrates data from drilling and production tests across 21 geothermal wells to analyze the Jixianian strata,including depth,thickness,temperature,single-well water yield,Groundwater Level Depth(GWD),and Total Dissolved Solids(TDS).Employing fuzzy mathematics,a zoning analysis was performed,yielding quantitative evaluation scores and delineating favorable zones for development.Key findings include:(1)Geothermal reservoirs in the Rongcheng and Niutuozhen uplifts exhibit shallow burial depths,substantial thicknesses,high productivity,and relatively low temperatures,making them highly suitable for large-scale geothermal exploitation;(2)Zones with high resource potential but uncertain conditions require further exploration to mitigate development risks;(3)Areas near the Rongcheng fault or Jixianian strata buried deeper than 4,000 m are recommended for deferred exploitation;(4)Comprehensive evaluation reveals that the Jixianian carbonate geothermal reservoirs in Xiong'an New Area manifest 168 geothermal resources of 5,370.31×10 J,geothermal fluid reserves of 101.17×10 m3,and recoverable fluid 4 reserves of 93.41×10 m3/d under balanced extraction and reinjection.Recoverable geothermal heat 164 amounts to 9.36×10 J/a,equivalent to 319.4×10 t/a of standard coal.This study provides valuable insights into the exploration and sustainable exploitation of deep geothermal reservoirs in Xiong'an New Area,enhancing resource utilization and contributing to the development of a green and sustainable Xiong'an New Area.
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financially supported by the National Natural Science Foundation of China(No.42277460)the Fundamental Research Project of Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological Sciences(No.SK202210).
文摘This study,based on Artificial Neural Network(ANN)technology,develops a quantitative prediction model for the unit water flow rate of the Quaternary strata in the Shijiazhuang-Hebei Plain area.The study area extends from the piedmont region of Shijiazhuang,at the eastern foothills of the Taihang Mountains,to the hinterland area of Hengshui within the plain in Hebei Province section of the North China Plain.The hydrological and exploration boreholes selected for modeling are primarily located in the south-eastern part of Shijiazhuang urban area—the southern region of Xinji County—north of Hengshui City near the Shenzhou County area.By employing the Induced Polarization method(IP)and Vertical Electrical Sounding(VES),apparent resistivity(ρS),apparent polarization rate(ηS),half-decay time(Th),and decay degree(D)were obtained as initial input parameters.These were combined with the measured water flow rates from borehole pumping tests to build the training sample set.To address the prevalent issue of high-salinity interference in the study area,multiple regression analysis revealed that when the inverted resistiv-ity(ρ)is less than 5Ω·m and the inverted polarization rate(η)is greater than 8%,the contribution of groundwater salinity to the resistivity parameter reaches 42%±6%.Based on this,a comprehensive parame-ter T"=ρ*H/ρ'was established,whereρis the aquifer resistivity,ρ'is the aquitard resistivity,and H is the aquifer thickness.The resistivity ratio effectively eliminates the coupling effect between electrical parame-ters and salinity.The input neurons of the improved model were adjusted to a four-parameter system consisting of decay time(Th),decay degree(D),deviation degree(σ),and the comprehensive parameter(T").Experiments showed that the prediction error of the model on the validation set was reduced from the original model's 5%-10%to 0.9%-5%.The introduction of the T"parameter reduced the prediction error in high salinity areas(Cl->500 mg/L)to within 7%.The study confirms that the composite parameter T"based on geophysical inversion parameters can effectively characterize the coupling features of aquifer thickness and water quality.Even with a small sample size,through algorithm optimization,data augmentation,and model structural improvements,it is entirely possible to effectively enhance prediction accuracy and gener-alization ability,providing a new parameterization method for the quantitative evaluation of Quaternary pore water in plain areas.
基金supported jointly by National Natural Science Foundation of China(NO.42430718)National Natural Science Foundation of China(NO.42077179)+2 种基金Natural Science Foundation of Fujian Province of China(NO.2023J01227)Natural Science Foundation of Xiamen,China(NO.3502Z20227309)Basic Scientific Research Business Expenses Project of the Chinese Academy of Geological Sciences(NO.YK202303).
文摘Developing a rapid and precise method for trace element analysis in geothermal water is crucial due to its high total dissolved solids and salinity,which can impact element determination.In this study,we optimized the determination of ferrum,manganese,strontium and barium in geothermal water samples collected from different regions.A matrix matching method was established for accurate quantification using Inductively Coupled Plasma Optical Emission Spectroscopy(ICP-OES).Instrumental conditions and experimental parameters were optimized,and the influence of storage medium and storage duration on measurement accuracy were evaluated.The results demonstrated that storing geothermal water samples in 1%nitric acid had no significant impact on measurement results over an eight-week period.Calibration curve correlation coefficients exceeded 0.9998 for all target elements.The detection limits of this method ranged from 0.0002 mg/L to 0.0031 mg/L,with Relative Standard Deviations(RSD)were 0.07%–2.33%,and spike recovery rates were from 96.8%to 103.2%.The obtained data were consistent with results from the standard addition method and dilution method,demonstrating the reliability of this approach.This method offers low detection limits,high precision and excellent recovery rate,providing a robust reference for the accurate determination of ferrum,manganese,strontium and barium in geothermal water,thereby laying a solid foundation for the development and utilization of geothermal resources.
文摘The groundwater in the research area is characterized by alkalescence,generally over-high EC value,and relatively low dissolved oxygen and oxidation-reduction potential.The pollution is presented by abnormal acid-base,dissolved oxygen reduction,and conductivity rise.The overall situation of groundwater chemical field is controlled by natural conditions,the hydrochemical type has obvious zoning feature and changes from single type to multiple types from the river bank of the Yellow River to both sides,and the local abnormality is closely related to the intensity of human activities.The pollution scope and degree of inorganic toxicological indexes and organic indexes are strongly correlated with land utilization type,pollution source distribution,urbanization,and pollutant disposal of the city,the pollution in the petrochemical industrial area is the most serious,and the organic pollution tends to escalate and diffuse to the downstream.
文摘A much improved understanding of how farmyard manure application may affect carbonate rock dissolution is needed in order to predict possible feedbacks between the rock carbon cycle and the global climate system. Two carbonate mineral rock tablets; dolomite and limestone were buried at six depths between 0 and 110 cm in a soil typical of the subtropical karst area in Guiyang City, Guizhou Province. The extent of tablet dissolution, soil CO2, soil p H, soil water content, soil mineral and chemical composition, and chemical composition of soil water were tested in order to assess the degree of dissolution under manure application over the course of one year. The results show that manure addition decreases the dissolution rate of carbonate rocks; limestone and dolomite by between 11.7%-116.9% and 25.0%-65.69% respectively, with the dissolution rate of limestone consistently exceeding that of dolomite under the same conditions. Our data indicates that the rate of pedogenesis of the dolomite and limestone rocks is decreased as much as 35.77% and 59.41% respectively, as a result of manure application. Moreover, the results suggest that manure application accelerated the generation of soil CO2, with soil CO2 concentration increasing on average by 93.94%, and the CO2 flux increasing by 67.64% compared with the control profile. Finally, the data also indicates that manure decreases CO2 uptake by dissolution of carbonate rocks by 25.50%-39.45% on a Guiyang city scale. The counteraction of the CO2 sink contributed by karst water due to farmyard manure utilization in general karst area（both dolomite and limestone） however was 59.41%-62.72%, indicating the application of manure successfully reduces both dissolution and CO2 release to the atmosphere.
文摘Dilution and attenuation factor (DAF) has a major influence on soil-to-groundwater screening level calculation for protection of contaminant migration from soil into groundwater at solid waste management units (SWMUs). Risk assessment guidance prepared by U.S. Environmental Protection Agency for site investigation and remediation suggests a default DAF of 20. If the base assumptions included in the default DAF are recognized to be not representative of site conditions at a SWMU, calculation of site-specific DAF is recommended when sufficient data are collected to justify using a different DAF value for development of soil screening levels. Commonly used methods of calculating DAF include analytical and numerical simulations that often require too many parameters to be obtained in practice. This paper proposes a probability method to develop site-specific DAF. The approach uses data that are readily available through field reconnaissance and site-specific investigation. A case study is presented in which the probability method was applied to an actual SWMU, and the calculated DAF is compared with that calculated from a dilution method. The probability-based DAF is 67 at 90% probability percentile, which is comparable to the dilution-based DAF of 76. Based on the calculated site-specific DAFs, SSLs could be developed for the contaminants of potential concern and used for evaluation of migration pathways from a contamination source through soil to groundwater. .
基金supported by the Natural Science Foundation of Hebei Province of China,China (No.D2015504008)the Fundamental Research Funds for the Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological Sciences,China (No.SK201707)Projects of China Geological Survey,China (No.DD20190331).
文摘A multi-isotope approach and mixing model were combined to identify spatial and seasonal variations of sources,and their proportional contribution to nitrate in the Hutuo River alluvial-pluvial fan region.The results showed that the NO3- concentration was significantly higher in the Hutuo River valley plain(178.7 mg/L) region than that in the upper and central pluvial fans of the Hutuo River(82.1 mg/L and 71.0 mg/L,respectively)and in the river(17.0 mg/L).Different land use types had no significant effect on the groundwater nitrate concentration.Based on a multi-isotope approach,we confirmed that the main sources of groundwater nitrate in different land use areas were domestic sewage and manure,followed by soil nitrogen,ammonia fertilizer,nitrate fertilizer and rainwater,and there were no significant spatial or seasonal variations.Combining δ^15N-NO3,δ^18O-NO3- and δ^37Cl results can increase the accuracy of traceability.Nitrification could be the most important nitrogen migration and transformation process,and denitrification did not significantly affected the isotopic composition of the nitrate.The SIAR model outputs revealed that the main nitrate pollution sources in groundwater and river water were domestic sewage and manure,accounting for 55.9%-61.0% and 22.6%(dry season),50.3%-60.4% and 34.1%(transition season),42.7%-47.6% and 35.6%(wet season 2016) and 45.9%-46.7% and 38.4%(wet season 2017),respectively.This work suggests that the random discharge and disposal of domestic sewage and manure should be the first target for control in order to prevent further nitrate contamination of the water environment.
基金supported by the Major State Basic Research Development Program (No. 2010CB428800)the Geological Survey Projects Foundation of Institute of Hydrogeology and Environmental Geology (No. SK201308)
文摘Understanding the controlling factor of groundwater quality can enhance promoting sustainable development of groundwater resources. To this end, multivariate statistical analysis（MA） and hydrochemical analysis were introduced in this work. The results indicate that the canonical discriminant function with 7 parameters was established using the discriminant analysis（DA） method, which can afford 100% correct assignation according to the 3 different clusters（good water（GW）, poor water（PW）, and very poor water（VPW）） obtained from cluster analysis（CA）. According to factor analysis（FA）, 8 factors were extracted from 25 hydrochemical elements and account for 80.897% of the total data variance, suggesting that groundwater with higher concentrations of sodium, calcium, magnesium, chloride, and sulfate in southeastern study area are mainly affected by the natural process; the higher level of arsenic and chromium in groundwater extracted from northwestern part of study area are derived by industrial activities; domestic and agriculture sewage have important contribution to copper, iron, iodine, and phosphate in the northern study area. Therefore, this work can help identify the main controlling factor of groundwater quality in North China plain so as to make better and more informed decisions about how to achieve groundwater resources sustainable development.
基金supported by National Natural Science Foundation of China(No. 41402234 and No. 41372243)the Fundamental Research Funds for Chinese Academy of Geological Sciences (No.YYWF201502)
文摘We present the first systematic hydrogeological analysis to grain insights on the evolution of the Gonghe Basin in North China. Two hundred and forty seven water samples were collected from the Gonghe East Basin, Gonghe West Basin and Chaka Basin. The three groundwater systems of Gonghe Basin from west to east display different geochemical signatures. Based on Na/Cl ratios and Langelier-Ludwig diagram, it is inferred that the groundwater recharge potential of the Gonghe East Basin is much prosperous than the other areas. The renewability of the aquifers in alluvial-proluvial fan of Wahonghe and Gonghe East Basin margin is much faster than in the other basins. The groundwater quality in Chaka Salt Lake,Shazhuyu and Qiabuqia River Valley plains is low due to strong evaporation and cation exchange. The groundwater quality of the phreatic aquifers in the Qiabuqia River Valley plain is further deteriorated by mixing of high-arsenic and high-mineralization water from the deep fault structures.
基金supported by grants from the Natural Science Foundation of China (no. 40973013,41173003)the Ministry of Land and Resources (no.201011027)+2 种基金China Geological Survey (no.1212011120298, 1212010816027)the Ministry of Science and Technology (no. K0802)the Open Foundation of Chinese Academy of Geological Sciences (no. 2009-SYS-06)
文摘Lithium separation technique for three reference materials has been established together with precise determination of lithium isotope using a Neptune multi collector-inductively coupled plasma mass spectrometry （MC-ICP-MS）. The solutions of lithium element standard reference materials, potassium, calcium, sodium, magnesium and iron single element, were used to evaluate analytical methods applied. Three separate stages of ion-exchange chromatography were carried out using organic cation-exchange resin （AG 50W-X8）. Lithium was enriched for the three stages using different eluants, which are 2.8 M HCl, 0.15 M HCl and 0.5 M HCl in 30% ethanol, respectively. The columns for the first and second stages are made of polypropylene, and those for the third stage are made of quartz. Total reagent volume for the entire chemical process was 35 mL for three reference materials. The recovery yielded for the three stages is 98.9-101.2% with an average of 100.0%, 97.6-101.9% with an average of 99.9%, and 99.8-103.3% with an average of 100.6%, respectively. The precision of this technique is conservatively estimated to be ±0.72-1.04‰ （2σ population）, which is similar to the precision obtained by different authors in different laboratories with MC-ICP-MS. The δ7 Li values （ 7 Li/ 6 Li relative to the IRMM-016 standard） determined for andesite （AGV-2） and basalt （BHVO-2） are 5.68‰ （n=18）, 4.33‰ （n=18）, respectively. The δ7 Li value （ 7Li/6Li relative to the L-SVEC standard） determined for IRMM-016 is -0.01‰ （n=15）. All these analytical results are in good agreement with those previously reported. In addition, the results for the same kinds of samples analyzed at the MLR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, are consistent with those obtained at the Plasma Laboratory, University of Maryland, within analytical uncertainty. According to these experiment results, it is concluded that this proposed procedure is a suitable method for determining the lithium isotopic composition of natural samples.
基金jointly funded by National Natural Science Foundation of China (41877398)project of the China Geological Survey (DD20221773)。
文摘Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound pollution.The root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dominated by Cd and Ni to varying degrees, especially wheat. As indicated by the health risk assessment results, the intake of maize in the study area does not pose significant human health risks;however, Cu has high risks to human health, and the compound heavy metal pollution caused by the intake of wheat in the study area poses risks to the health of both adults and children. Overall, the soils and crops in the study area suffer a high degree of heavy metal pollution, for which mining activities may be the main reason.
基金This work was financially supported by National Natural Science Foundation of China(41972262)Hebei Natural Science Foundation for Excellent Young Scholars(D2020504032)+1 种基金Central Plains Science and technology innovation leader Project(214200510030)Key research and development Project of Henan province(221111321500).
文摘Landslide is a serious natural disaster next only to earthquake and flood,which will cause a great threat to people’s lives and property safety.The traditional research of landslide disaster based on experience-driven or statistical model and its assessment results are subjective,difficult to quantify,and no pertinence.As a new research method for landslide susceptibility assessment,machine learning can greatly improve the landslide susceptibility model’s accuracy by constructing statistical models.Taking Western Henan for example,the study selected 16 landslide influencing factors such as topography,geological environment,hydrological conditions,and human activities,and 11 landslide factors with the most significant influence on the landslide were selected by the recursive feature elimination(RFE)method.Five machine learning methods[Support Vector Machines(SVM),Logistic Regression(LR),Random Forest(RF),Extreme Gradient Boosting(XGBoost),and Linear Discriminant Analysis(LDA)]were used to construct the spatial distribution model of landslide susceptibility.The models were evaluated by the receiver operating characteristic curve and statistical index.After analysis and comparison,the XGBoost model(AUC 0.8759)performed the best and was suitable for dealing with regression problems.The model had a high adaptability to landslide data.According to the landslide susceptibility map of the five models,the overall distribution can be observed.The extremely high and high susceptibility areas are distributed in the Funiu Mountain range in the southwest,the Xiaoshan Mountain range in the west,and the Yellow River Basin in the north.These areas have large terrain fluctuations,complicated geological structural environments and frequent human engineering activities.The extremely high and highly prone areas were 12043.3 km^(2)and 3087.45 km^(2),accounting for 47.61%and 12.20%of the total area of the study area,respectively.Our study reflects the distribution of landslide susceptibility in western Henan Province,which provides a scientific basis for regional disaster warning,prediction,and resource protection.The study has important practical significance for subsequent landslide disaster management.
