Relationship between spatio-temporal evolution of soil pH and geological environment/surface cover in the eastern Nenjiang River Basin of Northeast China during the past 30 years

To illuminate the spatio-temporal variation characteristics and geochemical driving mechanism of soil pH in the Nenjiang River Basin,the National Multi-objective Regional Geochemical Survey data of topsoil,the Second National Soil Survey data and Normalized Difference Vegetation Index(NDVI)were analyzed.The areas of neutral and alkaline soil decreased by 21100 km^(2)and 30500 km^(2),respectively,while that of strongly alkaline,extremely alkaline,and strongly acidic soil increased by 19600 km^(2),18200 km^(2),and 15500 km^(2),respectively,during the past 30 years.NDVI decreased with the increase of soil pH when soil pH>8.0,and it was reversed when soil pH<5.0.There were significant differences in soil pH with various surface cover types,which showed an ascending order:Arbor<reed<maize<rice<high and medium-covered meadow<low-covered meadow<Puccinellia.The weathering products of minerals rich in K_(2)O,Na_(2)O,CaO,and MgO entered into the low plain and were enriched in different parts by water transportation and lake deposition,while Fe and Al remained in the low hilly areas,which was the geochemical driving mechanism.The results of this study will provide scientific basis for making scientific and rational decisions on soil acidification and salinization.

Geological environment in the South China Sea

The South China Sea(SCS),situated in southern China,at the junction of the Pacific Plate,the Eurasian Plate,and the Indian Ocean Plate,is a northeast-southwest trending semi-enclosed sea.It spans an area of approximately 3.5 million square kilometers and has an average water depth of about 1200 m,its deepest point reaching 5559 m.In 2021,a scientific expedition(called as U1 voyage)in the South China Sea was organized by the Innovation Research Team of Guangdong Special Key Program from March to April,this marks the first comprehensive scientific research voyage to the southern Uboundary corridor.Consisting of a total of 30 papers,this special issue is to share a portion of the research findings from this scientific expedition U1 voyage,covering six aspects:1)characteristics of the marine ecosystem in the SCS and its response to marine dynamic processes;2)multi-scale marine dynamic processes,sea-air interactions,and forecasting techniques in the SCS;3)geomorphology and geological structure;4)sedimentary processes and resource potential in the SCS;5)geostrategy,rights and interests maintenance and strategic countermeasures in the SCS;6)marine scientific instruments.By integrating the scientific research with the study of history,jurisprudence and international strategies,this issue presents new insights into the formation history and scope evolution of the SCS,and it also seeks to establish a new scientific framework based on the marine governance and development of the SCS.

Deep seabed mining:Frontiers in engineering geology and environment

Ocean mining activities have been ongoing for nearly 70 years,making great contributions to industrialization.Given the increasing demand for energy,along with the restructuring of the energy supply catalyzed by efforts to achieve a low-carbon economy,deep seabed mining will play an important role in addressing energy-and resource-related problems in the future.However,deep seabed mining remains in the exploratory stage,with many challenges presented by the high-pressure,low-temperature,and complex geologic and hydrodynamic environments in deep-sea mining areas,which are inaccessible to human activities.Thus,considerable efforts are required to ensure sustainable,economic,reliable,and safe deep seabed mining.This study reviews the latest advances in marine engineering geology and the environment related to deep-sea min-ing activities,presents a bibliometric analysis of the development of ocean mineral resources since the 1950s,summarizes the development,theory,and issues related to techniques for the three stages of ocean mining(i.e.,exploration,extraction,and closure),and discusses the engineering geology environment,geological disasters,in-situ monitoring techniques,envi-ronmental protection requirements,and environmental effects in detail.Finally,this paper gives some key conclusions and future perspectives to provide insights for subsequent studies and commercial mining operations.

Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,Major and Trace Elements

The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were studied.The above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater conditions.Comparatively,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and salinity.During the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant algae.Moreover,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial input.The OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and bacteria.Tectonic subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct differences.Overall,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace elements.The established models may have positive implications for research of lacustrine source rocks in offshore areas with few drillings.

Risk-based evaluation on geological environment carrying capacity of mountain city - A case study in Suide County, Shaanxi Province, China

With the rapid development and expansion of the cities in China, the carrying capacity of resource and environment has become a huge concern for local governments. From the perspective of geological environment, geological disasters are the main restraining factor of the development in mountain cities. This study was conducted in Suide County of Shaanxi Province with a risk-based approach as followed: a hazard analysis on geological disasters based on a slope geological survey at a scale of 1:10,000; a consequence analysis based on unmanned aerial vehicle(UAV) aerial survey data; integrating the results of hazard analysis and consequence analysis, a risk zonation and analysis of geological disasters in urban areas were completed considering urban planning, land use planning and the safety of infrastructure and major engineering. Subsequently, taking the acceptable levels of human life and property risks incurred by landslides as the criteria of the evaluation of geological environment carrying capacity, a comprehensive assessment of current and future urban carrying capacity was conducted based on the results of the risk analyses. Accordingly, the prior development zone, the restricted development zone and the prohibited zone were delineated, with corresponding suggestions for future urban development. The technological and methodological system used in the study can be applied to geological environment carrying capacity evaluation of other important mountain cities, which can provide scientific basis for the optimization of land and space.

Geological resources and environmental carrying capacity evaluation review,theory, and practice in China

Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict development in a region.In this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is studied.Then a "coordination theory of resources and environmental carrying"is proposed.Next,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first time.This paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity evaluation.Finally,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods.

An overview of the resources and environment conditions and major geological problems in the Yangtze River economic zone, China

Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land planning and construction are studied.The results show that the resource conditions of cultivated land,shale gas,geotherm,lithium and so on are superior in the Yangtze River economic zone,and the resources and environment conditions are conducive to develop the modern agriculture,clean energy industry and strategic emerging industries.3×1013 m^2 farmlands without heavy metal pollution are concentrated;there are three national level shale gas exploration and development bases with explored reserves of 5.441×1011 m^3;geothermal availability is 2.4×109 t of standard coal each year,equivalent to 19% of the amount of coal in 2014;Asia's largest energy lithium metal ore deposit is found.In some parts of Yangtze River economic zone,there are some major geological problems such as active faults,karst collapse,ground subsidence,landslide-collapse-debris flow,affecting the river-crossing channels,high-speed railway,urban agglomeration and green ecological corridor planning and construction.Those problems should be concerned,and the relevant suggestions and countermeasures are put forward.Meanwhile,the ideas to further support the development of the Yangtze River economic zone are put forward.

The response between glacier evolution and eco-geological environment on the Qinghai-Tibet Plateau

Based on the remote sensing survey and monitoring results of snow lines on the Qinghai-Tibet Plateau, the authors analyzed the following eco-geological factors such as water resources, permafrost, desertification, wetlands, lake, geological disasters, sea-level rising, earthquake, etc., affected by the change of snow lines over the past 40 years, and discuss the response between glacier evolution and the eco-geological environment preliminarily.

Comprehensive suitability evaluation of urban geological environment in Zhengzhou-Kaifeng area

Suitability evaluation of urban geological environment is an important basic work in city planning and construction. With Zhengzhou-Kaifeng area as the research area, this paper discusses AHP and fuzzy comprehensive evaluation methods to classify impact factors at different levels, makes a mixing evaluation of the basic factors and comprehensive factors so as to correct the uncertainty of the weight of the basic factors in the initial evaluation and establish the corresponding evaluation index system, and carries out urban geological environment suitability evaluation in study area. Furthermore, this paper partitions the suitability of the research area according to evaluation results into five zones. It puts forward opinions and suggestions for the construction of research area, which have certain practical significances.

Urban Geological Environment and Land-Utilization Evaluation in Xi'an

In this paper, the urban geosciences with the geological environment of Xi'an as an example are studied in detail. A corresponding model is employed to make a comprehensive evaluation of the land-use capacity, providing a scientific base for the controlling measures of the urban land-use project.

Distribution and impacts on the geological environment of antiviral drugs in major waters of Wuhan,China

This study investigated water samples collected from the surface water and groundwater in Wuhan City,Hubei Province,China in different stages of the outbreak of the coronavirus disease 2019(hereinafter referred to as COVID-19)in the city,aiming to determine the distribution characteristics of antiviral drugs in the city’s waters.The results are as follows.The main hydrochemical type of surface water and groundwater in Wuhan was Ca-HCO3.The major chemical components in the groundwater had higher concentrations and spatial variability than those in the surface water.Two antiviral drugs and two glucocorticoids were detected in the surface water,groundwater,and sewage during the COVID-19 outbreak.Among them,chloroquine phosphate and cortisone had higher detection rates of 32.26%and 25.80%,respectively in all samples.The concentrations of residual drugs in East Lake were higher than those in other waters.The main drug detected in the waters in the later stage of the COVID-19 outbreak in Wuhan was chloroquine phosphate,whose detection rates in the surface water and the groundwater were 53.85%and 28.57%,respectively.Moreover,the detection rate and concentration of chloroquine phosphate were higher in East Lake than in Huangjia Lake.The groundwater containing chloroquine phosphate was mainly distributed along the river areas where the groundwater was highly vulnerable.The residual drugs in the surface water and the groundwater had lower concentrations in the late stage of the COVID-19 outbreak than in the middle of the outbreak,and they have not yet caused any negative impacts on the ecological environment.

Geological Environment Problems Caused by Controlling Groundwater Exploitation in Jiangyin City

Geological environment effects caused by the control of groundwater exploitation in Jiangyin city are discussed thoroughly, including the dynamic variation of groundwater levels and quality and the development of land sub-sidence and ground fissures. According to the dynamic characteristics of groundwater levels, some advice about groundwater exploitation is offered. Our research will provide a basis for using groundwater resources and the preven- tion of geological disasters in Jiangyin city and the Suzhou-Wuxi-Changzhou area. The following results are deduced from our research. First, groundwater levels vary with the exploitation of groundwater in Jiangyin city and are affected by hydrogeological conditions. The groundwater levels remained rather stable before and after the implementation of control of groundwater exploitation in the northwest of Jiangyin city along the Yangtze River. A suitable level of exploitation should be allowed. In the southeast, the speed of recovery of the groundwater level has been rather rapid after the control of exploitation. We conclude that groundwater might be exploited locally after the groundwater level has recovered. In the southwest, the speed of recovery of the groundwater level is rather slow and exploitation of ground-water should be prohibited. Second, groundwater quality is stable in Jiangyin city and the contents of the main chemical indices of groundwater varied only slightly before and after the control of exploitation. Third, after controlling the exploitation, the speed of land subsidence has clearly slowed down and the development of ground fissures has been controlled effectively.

Analysis of the negative effects of groundwater exploitation on geological environment in Asia

This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are generally as follows:(1) Constant decrease of groundwater level is mainly distributed in China(East Asia), India(South Asia), Tajikistan(Central Asia) and Saudi Arabia(West Asia);(2) land subsidence occurs mainly in eastern plains of East Asia and west Siberian Plain of North Asia;(3) seawater intrusion occurs mainly in China, Japan and South Korea in East Asia, Philippines and Indonesia in Southeast Asia, the Indian coastal areas in South Asia;(4) groundwater level decline caused by groundwater exploitation in oil fields;(5) mining collapse is mainly in 50° to 70° north latitude band;(6) the total area of karst collapse in China of East Asia is as much as 197.05 km^2; and(7) ground fracture is mainly distributed in the North China Plain, Fenwei Plain and the Yangtze River Delta. Asia can be divided into 6 zones in terms of the geological environment negative effect caused by groundwater exploitation. According to analysis, with the increasing intensity of human activities, geological environment issues become more and more serious, therefore it is vital to control the human activities within the scope of 5× 10~5 people/km^2 to 9.9× 10~5 people/km^2 for the effective control of the size of the affected area by geological environment problems.

Geological Environmental Adaptability of Qingdao Rural Urbanization Based on Fuzzy Mathematical Method

Fuzzy mathematics comprehensive evaluation method is used to evaluate the geological environment suitability of rural urbanization in Qingdao City,China.A total of 5 first-level evaluation factors are selected,including environmental geological condition,geological resources,engineering geological condition,geological disaster and environmental geological problem,and human engineering activity.And there are 27 second-level evaluation factors,such as topography,land type and vegetation,nature reserve,water source protection area,groundwater quality division,and major engineering project.Qingdao City is divided into four districts of suitable area,relatively suitable area,moderately suitable area and relatively unsuitable area of ecological environment.And their characteristics are introduced.Suggestions for the developing direction of urban construction are put forward.Region of Laoshan District lying to the west of the Shilaoren is suitable to set up high-rise building;west Hongshiya may establish a waste landfill site;Jiaozhou Bay,the downstream of Dagu River,and Jihongtan Reservoir should be built as the key geological environment protection area and water source protection area.And the north Hongdao should be strictly monitored in order to control the expansion of urban construction to Jihongtan Reservoir.Mocheng District and the area north of it,Jiaozhou District and the area east of it are the ideal urban construction development areas in Qingdao City in the future.

Evaluation of Mine Geological Environment of Guqiao Coalmine

The geological environment is important for the development of coal enterprises. In the Guqiao coalmine, the information of coal mining subsidence, terrain landform, coal gangue utilization, mine water treatment and several on-site investigations have been analyzed. It holds that its geological environment can be evaluated from three aspects, i.e., geological disasters, terrain and landform destruction, and influence on water and soil environment. The results show that mining activities have serious impacts on geological disasters and terrain landform, while lighter impacts on the water and soil environment. According to the research results, a set of corresponding governance strategies are given. The findings can provide theoretical support for the geological environmental protection and restoration of the Guqiao coalmine.

Study of Fussy Clustering of Engineering Geological Environment with GIS

Based on previous evaluating methods, a new method which combines GIS with Fussy Clustering algorithm is proposed and applied in evaluating the engineering geological environment of the research area of XuZHou City in this paper. By analyzing the characteristics and formation of engineering geological environment,the major problems are discussed, including stability of basement rock, sandy soil liquefaction and cultural stratum.According to effecting factors of these problems, the stability of every engineering geological problem in the worked area is classified into different classes. Then, the Fussy Clustering method is used in assessing all conditions of engineering geological environment. Finally, the evaluation is fulfilled in the whole studied area. The calculating result shows the method is feasible.

Environment Geological Effect of Groundwater Exploitation in Linfen

Through analyzing environment geological effect of groundwater in detail, the authors hold that the groundwater exploitation is excessive in Linfen City. A regional depression cone has been formed in the civic center; The subsidence scale keeps increasing, and five developed earth fissure hazards zones have been formed. This hinders the sustainable economic development of Linfen severely. Large scale observation net of groundwater should be established to dynamically monitor the ground water, ensuring a rational exploitation.

Geological environment impact analysis of a landfill by the Yangtze River

In order to assess the geological environment impact of a city landfill by the Yangtze River, soils from different depths in the dumpsite were sampled and analyzed. It was found that pollutants content at the site was distinctly higher than that in nearby environments. The content of heavy metals, such as Cd, Hg, As, Pb and Cu, reduces as depth increases; the content of elements F, Cl and N is the contrary. Pollutants migration driven by underground water flow was analyzed, considering the hydro-geological conditions of the site. It is believed that, due to leaching after rainfall infiltration, pollutants in the garbage layer migrates deeper, the cohesive soil in the underlying surface prevents them from spreading to the deeper aquifer; additionally, the high pressure tolerance of the deep groundwater is a key factor in preventing pollutants from entering the aquifer. Furthermore, human control has reduced the annual fluctuation range of water level in nearby rivers, weakening the hydrodynamic relations with phreatic water, and thus reducing the spreading of pollutants to nearby surface waters.

Status of China's Geological Survey and Geological Environments in 2013

With the approach of the 45th World Earth Day,China＇s Ministry of Land and Resources issued the status of the Chinese geological survey and environments on 22nd April 2013.Regional geological survey in 2013 achieved new results-（why was oceanic in twice？） polar and oceanic expedition were fully completed,a national census of geography was begun,and the security capacity of mapping geographic information was enhanced.A new idea for integrated geological survey and scientific research was proposed to enhance marine geological surveys and to improve service capabilities.

Spatial data modeling for coalfield geological environment

Presented a study on the design and implementation of spatial data modelingand application in the spatial data organization and management of a coalfield geologicalenvironment database.Based on analysis of a number of existing data models and takinginto account the unique data structure and characteristic, methodology and key techniquesin the object-oriented spatial data modeling were proposed for the coalfield geological environment.The model building process was developed using object-oriented technologyand the Unified Modeling Language (UML) on the platform of ESRI geodatabase datamodels.A case study of spatial data modeling in UML was presented with successful implementationin the spatial database of the coalfield geological environment.The modelbuilding and implementation provided an effective way of representing the complexity andspecificity of coalfield geological environment spatial data and an integrated managementof spatial and property data.