Artificial tracer test is an important research method in the field of karst hydrogeology. In this study, to understand the distribution characteristics of karst conduits more comprehensively, multisource tracer tests were carried out on the Cangpuwa underground river in the base flow period and precipitation conditions. The results showed that tracers from Shuiqing, Huangliancun, and Liaojiapo were detected in the base flow period and precipitation conditions. The tracer recoveries under precipitation conditions were 88.12%, 90.01%, and 84.01%, respectively, indicating that the Cangpuwa underground river was a multisource and single-sink underground river. According to the tracer transport characteristics in both the base flow period and precipitation conditions, a conceptual model of the Cangpuwa underground river karst conduit structure was constructed. The flow path from Shuiqing to Cangpuwa had the largest curvature, the flow path from Huanglian to Cangpuwa was mainly a karst conduit, there were two channels on the flow path from Liaojiapo to Cangpuwa, and there was a dissolved pool near the outlet of the underground river. The research results can provide a basis for the investigation and exploitation of water resources in complex karst underground rivers.

人工回灌条件下回灌水与地下水混合带的水-岩相互作用是决定地下水水质演化和含水层发生化学堵塞的关键过程.为研究人工回灌对滹沱河地下水超采区水质演化的影响,以石家庄市人工回灌场地为例,利用石津灌渠水作为回灌水源,通过室内实验结合反向水文地球化学模拟揭示回灌层位地表水与地下水混合带的水-岩相互作用机理.结果显示:混合带水的TDS(total dissolved solids)变化特征表现为先增大后缓慢降低,且地表水占比越大、含水介质粒径越细,则其变幅越大;混合带水中主要离子质量浓度变化特征受混合、碳酸平衡、溶解-沉淀、阳离子交换及硝化作用控制,其中K+、Ca2+、SO2-4质量浓度主要受溶解-沉淀作用控制,Na+、Cl-、HCO3-、NO3-质量浓度主要受混合NO3-作用控制,Mg2+质量浓度主要受阳离子交换作用控制;水-岩相互作用过程中溶解的矿物有石膏、钠长石、钾长石及盐岩,析出的矿物有方解石、钙蒙脱石及石英,且在地表水占比越大、含水介质粒径越细的层位,方解石的沉淀量越大,表明在粒径较细的回灌层位存在碳酸岩盐的化学堵塞风险.

为了研究土地利用方式变化在典型岩溶流域产生的水文响应,构建了倒天河流域的SWAT模型,利用该模型探讨了不同土地利用情景下流域流量的变化规律和子流域产水量的变化规律及其调蓄能力分析,结果表明:参数率定后的SWAT模型在模拟倒天河流域月流量过程中表现良好,模型适用于该研究区;草地转为耕地会导致流域流量增加,调蓄能力减弱;林地向耕地、草地向耕地转化易改变子流域产水量,草地向林地的转化不易改变子流域产水量;林地向耕地、草地向耕地、草地向林地的土地利用转化均会导致子流域调蓄能力变弱,草地向耕地的转化对调蓄能力的改变尤为显著.研究成果对减轻岩溶区旱涝灾害,防治石漠化有重大意义.

岩溶地下河的存在严重影响了土壤和水评估工具(SWAT)在岩溶地区的普遍适用性.针对岩溶地下河在SWAT中的概化问题,提出基于数字高程模型(DEM)预处理结合SWAT流域自动识别功能的方法,将岩溶地下河暴露于地表,把岩溶区复杂的地表-地下二元结构简化为地表一元结构,并以贵州毕节地下河发育的倒天河流域为例进行应用.结果表明:① 对比未经概化地下河建立的模型,概化地下河建立的模型识别流域面积增大30.73％,子流域个数增加29.27％,水文响应单元(HRU)个数增加43.82％;② 参数取最大物理意义范围时,未经概化地下河建立的模型p因子=0.64,不满足建模条件,物理模型本身存在问题;③ 概化地下河建立的模型月步长模拟结果:校准期R2=0.96,NS=0.96,验证期R2=0.94,NS=0.93,月尺度模拟效果非常好.岩溶地下河概化方法使SWAT在流域划分方面更加合理,搭建的模型模拟更加合理.该研究拓展了SWAT模型在岩溶区的应用.

The source characterization of nitrate (NO3−) in groundwater of Muling-Xingkai Plain (MXP) and the influence of NO3− on the water environment were studied by hydrogeochemical and multivariate statistical analysis. A total of 164 groundwater samples were collected, and the samples were classified into three clusters by using hierarchical cluster analysis. Cluster 1 (C1), accounting for 13% of total samples, was mainly located in local residential zones where the top soils were the medium-textured sediments. Cluster 2 (C2) and cluster 3 (C3) were mainly located in farmlands and residential zones where the clay sediments were overlaying the aquifers. The soil media covering the aquifers was an important factor controlling the concentration of NO3− in groundwater, which determined the infiltration rate of wastewater and the redox environment of aquifers. Only the samples in C1 exceeded the WTO standards for NO3− (50 mg/L), and the samples in C2 and C3 had low NO3− concentration (less than 10 mg/L). The excessive NO3− in groundwater was observed in the shallow groundwater under local residential zones, and it was closely related to the anthropogenic activities since the 1950s. The domestic sewage was responsible for the elevated NO3− contents in the MXP. Then, it was still necessary to construct the sewage disposal system in rural areas to further protect the groundwater resource to avoid the formation of extensive nitrogen pollution. At present, NO3− in the groundwater mainly shows a fertilizer and natural rainwater origin and is not demonstrating the significant deterioration of groundwater qualities and water environment.

Iodine-rich groundwater is a cause for concern because it is harmful to human health, and determining the sources of groundwater iodine in coastal urbanized areas is complicated. This study aims to delineate the spatial distribution of groundwater iodide in various shallow and unconfined aquifers, as well as in areas with different urbanization levels in the Pearl River Delta (PRD), and to identify the origins of iodide-rich (>0.08 mg/L) groundwater in this region. Approximately 400 groundwater samples, 10 surface water samples, and 9 leachate samples were collected, and a total of 17 chemicals were analyzed. The result showed that iodide-rich groundwater was present in 13.95% of shallow granular aquifers and 6.82% of shallow fissured aquifers; however, it was not present in karst aquifers. In shallow granular aquifers, the proportions of iodide-rich groundwater in areas with different urbanization levels were similar. On the other hand, in shallow fissured aquifers, iodide-rich groundwater mostly appeared in urbanized areas, and its proportion was more than three times that of non-urbanized areas; however, it was not present in peri-urban areas. The reductive dissolution of iodine-loaded Fe/Mn (oxy)hydroxides and decomposition of iodine-rich organic matter in sediments were likely the main sources of iodide-rich groundwater in shallow granular aquifers. Urbanization accompanied by wastewater leakage was also a significant source for iodide-rich groundwater in granular aquifers of urbanized areas. In contrast, the degradation of organic matter in carbonate-rich rocks and urbanization accompanied by leakage of reductive sewage were most likely responsible for the occurrence of iodide-rich groundwater in shallow fissured aquifers. The leakage of landfill leachate was also a significant source for iodide-rich groundwater in the fissured aquifers of non-urbanized areas.

Tritium (3H) and radiocarbon (14C) were used to determine the age, to delineate a flow regime, and to estimate flow velocity of medium-depth groundwater (50–200 m) from a Middle and Upper Pleistocene confined aquifer. Young groundwater age was determined using 3H and an exponential piston-flow model (EPM). Three correction models (Tamers, Pearson, and Fontes and Garnier) were chosen to date the 14C age of old groundwater. Groundwater ages of the medium-depth groundwater ranged from 3.5–25,790 a. Groundwater is relatively young in most of the piedmont area, although two high-age zones (with ages > 20,000 a) exist in the center of the plain. Groundwater age distribution characteristics indicated that groundwater flows from the mountain area to the basin area, and that the oldest groundwater in each high-age zone flows toward the depression cones. Two large local flow systems were formed because of overexploitation, and the regional flow system from north to south no longer exists. This study delineated the age of medium-depth groundwater in the entire Taiyuan Basin for the first time. The results can help promote the sustainable use of groundwater in the Taiyuan Basin.

Industrialization and urbanization expansion may change the groundwater quality in the Pearl River Delta (PRD). The aims of this study were to evaluate the groundwater quality in various aquifers and areas with different urbanization levels in the PRD, to extract the main impact indicators, and to discuss the driving forces for the groundwater quality. Nearly 400 groundwater samples were collected and 23 indicators were analyzed. In the PRD, 83% groundwater was drinkable (good-quality) by using a fuzzy synthetic evaluation method. Groundwater in karst aquifers was drinkable, and its quality was better than those in granular and fissured aquifers. In the latter two aquifer types, groundwater quality in non-urbanized areas was much better than those in peri-urban and urbanized areas. In granular aquifers, Mn + Fe, I- + Ni + Mn, and Mn + As + I- were the main impact indicators for poor-quality groundwater in urbanized areas, peri-urban areas, and non-urbanized areas, respectively. Correspondingly, reductive dissolution of Fe/Mn (oxy)hydroxides, infiltration of industrial wastewater and reductive dissolution of I- and Mn, and reductive dissolution of Mn, As, and I- were likely responsible for poor-quality groundwater in these areas, respectively. By contrast, in fissured aquifers, NO3-, NO3- + Pb, and I- were the main impact indicators for poor-quality groundwater in urbanized areas, peri-urban areas, and non-urbanized areas, respectively. Correspondingly, infiltration of domestic sewage, infiltration of domestic sewage and industrial wastewater, and mineralization of I-rich organic matter were probably responsible for poor-quality groundwater in these areas, respectively. Industrialization was one of the main driving forces for groundwater quality in granular and fissured aquifers in peri-urban areas, while urbanization was one of the main driving forces for groundwater quality in fissured aquifers in urbanized and peri-urban areas in the PRD.

贵州地区旱涝灾害频发,为深入研究贵州地区降水特征,运用0-1测试方法对贵州省33个雨量站不同时间尺度下降水序列值进行了混沌识别及降水混沌特性的空间分布特征研究,并研究高程与纬度对贵州降水混沌特性的影响.结果表明:贵州地区降水在旬、月、双月与季尺度下均具有明显的混沌性,且随时间尺度的增大而降低;降水混沌特性的空间变化特征总体上呈东北高西南底的特点,反映出贵州北部地区与西南部地区的降水特征具有明显差异,且气候条件是决定降水混沌特性变化的主要因素;高程与降水混沌特性负相关,在双月、季尺度下的相关系数分别为0.68、0.74;纬度与降水混沌特性呈正相关,在双月、季尺度下相关系数分别为0.43、0.49.该结果可为研究降水系统的时空变化规律提供参考.

采用单指标法和综合评价法,对吕梁市盆地区中深层地下水(50～200 m)质量进行了评价与分析;采用数理统计方法和水化学图示方法对研究区地下水质量的影响因素进行了识别.地下水质量评价结果表明,研究区地下水质量总体较差,多数地下水样品点属于Ⅳ类或Ⅴ类.地下水质量劣化的主要贡献指标是Fe、Mn、As、I-和F-,局部区域存在NO;和Cl-的影响.影响因素识别和分类结果显示,研究区地下水质量主要贡献指标(Fe、Mn、As、I-和F-)的富集均受到水文地质条件和地层岩性等天然因素的控制.部分地区NO3-和Cl-的升高是受人类活动影响的结果.吕梁市盆地区地下水质量特征与影响因素研究,对于保障供水安全和预防地方病具有重要意义.

To reveal the evolution mechanism of groundwater quality in Liulin karst system in northern China,we used the major ions and saturation indices to analyze the hydrochemical characteristics and geochemical processes.Meanwhile,we established a reverse geochemical model to quantitatively simulate the water-rock interactions in karst aquifers.The results showed that the hydrochemical type changed from HCO3-Ca·Mg in the recharge area to HCO3·SO4-Ca·Mg in the runoff area and to HCO3·SO4-Ca·Na in the discharge area.The ge-ochemical processes of hydrochemical evolution in karst water were the dissolution of carbonate minerals and gypsum.Along the flow path, the processes were evolved from the simultaneous dissolution of calcite and dolomite in the recharge area to the dissolution of dolomite and gypsum in the runoff area,and the dissolution of halite was added in the discharge area.Besides,the dedolomitization and cation exchange between Na+and Ca2+in the runoff and discharge areas affected the hydrochemical types of karst groundwater in Liulin.

The report on the 18th National Congress of Communist Party of China put forward the idea that construction of ecological civilization should be integrated into economic, political, cultural and social construction so as to achieve the aim of “five-in-one”. This development strategy will have an important guidance for the future development of science. For the purpose of building an ecological civilization as the basic starting point and according to the natural conditions of its development effects, this paper summarizes different types of urbanization development and points out the necessity of acting according to circumstances at this stage of the urban population. And then a discussion is made on the geological environment problems in the process of development, with special emphasis placed on the prevalent security issues of water and soil resources, natural disasters of extreme hazards, adverse large-scale integrated environmental effects of the construction and development, and environmental pollution hazards. This paper points out the safety feasibility and importance of the development of new urbanization in accordance with environmental safety and sustainable development. Based on the above analysis and discussion, the authors have divided urban construction into five levels, and discussed the functions of different levels of towns. Importance is attached to the integration and coordinated development of urban and rural areas.

Bacterial sulfate reduction is significant for the karst development and pyrite formation within the Ordovician weathering crust in the Ordos Basin of China. Bacterial communities were studied to determine their potential geomicrobiological functioning by constructing 16S rRNA clone library for in situ samples. The results showed that 147 positive clones sequenced were divided into 23 operational taxonomic units (OTUs), 8 OTUs accouting for 80% of all the selected clones belonged to the genus Desulfosporosinus. Bacterial sulfate reduction has been demonstrated to take place in the Ordovician by the classical hydrogeological information together with the stable sulfur isotope analysis from both the pyrite in the weathering crust and the products of the laboratory experiments on the dissolution of sulfate rock. The H2S produced by bacterial sulfate reduction combined with iron to form pyrite, resulting in the development of hypogenic karst in the weathering crust. This process provided a reasonable interpretation for karst development in the vicinity of sulfur deposits in the Ordos Basin.

For studying dissolution mechanism of limestone in different periods of reservoir storage in the karst region,a simulation experiment equipment was designed using self developed pressure dissolution test equipment of rocks in open system. Experiments were performed in carbonic acid solutions,under hydrodynamic pressure from 0 to 2 MPa and temperature from 15 ℃ to 85 ℃. The results showed that the degree of limestone dissolution increased with the increase of hydrodynamic pressure and temperature. Dissolution rates decreased first and then increased with the increase of water pressure,but they increased first and then decreased with temperature increasing,and the maximum value occurred at75 ℃. This experimental method and it's results provided a theoretical basis for the carbonate water-rock interaction analysis and the sustainable development of hydropower engineering in the karst region.

Through determination of river water,river sediments,soil profiles along the river,and groundwater,the distribution characteristics of BTEX,which were detected in the water of Cihe River in the piedmont plain of Taihang Mountains,was studied systematically.The results showed that the contaminants in different media are closely related.The soil samples from different depth and distance of the profiles along the river indicated that BTEX are mainly from the river.Because of the attenuation processes(e.g.adsorption to soils),the content of organic contaminants in soils decreases significantly with depth and distance from the river.The data of shallow groundwater samples from the well of different distance from the river showed that the organic contaminants were only detected in a few wells and their concentration can still meet the standards of drinking groundwater.

With the acceleration of industrialization course,the organic pollution in groundwater is becoming more and more serious.390 samples were collected from Hutuo alluvial plain shallow groundwater,base on the test and analysis of these samples,the following results were obtained:(1) the detection rate of chloroform in Hutuo alluvial plain shallow groundwater was up to 15.64%;(2) the chloroform concentrated detected areas were all located in industrial distributing centre and sewage canals;(3) the lithology of chloroform detected area and the unsaturated zone presented perfect unanimity;(4) the groundwater ubiquity score of chloroform in soil and sediment were 4.71 and 6.31 respectively,which means high leaching property.Other organic compounds also had high GUS value,so they could pollute the groundwater and soil easily.

The groundwater quality is highly influenced by input of contaminants from various sources.In order to acquire the cur-rent status of groundwater quality in the North China Palin(NPC),245 water samples were collected according to the relating reqirements and standards.The samples were analysed by qualified laboratories.The investigation results showed that there were 32 organic contaminants detected in groundwater in the NPC.Among these compounds,the detection frequencies(ratio of number of samples with organic compound(s) detected to the total number of samples) of chloroform,toluene,tetrachloroethylene,benzo[a]pyrene xylene,chlorobenzene,benzene,and 1,2-dichlorobenzene are higher than 4.5%.According to the standards of groundwater quality(China Geological Survey,2007),the concentrations of carbon tetrachloride,benzo[a]pyrene,and volatile phe-nols some water samples(2.5% of the total) were higher that that for class III,which corresponds to the drinking water standards.It should be noted that there were organic contaminants detected in some deep groundwater samples.This suggests that further moni-toring work should be carried out for these sites.Normally,the higher detection frequency of organic contaminants corresponds to reagion with intensive human activities,especially in the pediment reagion,due to its high permeability of the geological media.The results preliminarily indicated that there is a correlationship between the organic contaminantion and the increase of the water hard-ness.Due to the high temporal and spatial heterogeneity of groundwater organic contamination,it is suggested that further monitor-ing work should be carried out for these sites where organic contaminants were detected.

In the investigation of groundwater contamination,the selection of monitoring target organic compounds is very important for the correct assessment of the real situation of groundwater contamination.According to organic compounds involved in the main standards currently used in the world,29 items,which are not included in the Guidelines of Groundwater Contamination Investigation(CGS,2006),are put forward in this paper in the hope that they can be wholly or partly considered in the groundwater contamination investigation in terms of the actual hydrogeological condition and the contaminant sources in the study area.It is suggested that more attention should be paid to the compounds with high mobility and high pathogenic risks.

Wastewater irrigation can save water resources to a certain extent,but irrational utilization of wastewater can also cause pollution of groundwater.This paper reviews such an issue caused by wastewater irrigation in different cases,which is normally identified as increasing nitrate,hardness,heavy metals,pathogenic microbes,and organic compounds in groundwater.The mechanisms of migration and natural attenuation of pollutants are discussed,and the factors influencing the transport and transformation of contaminants in vadose zone are also examined.Subsequently,the measures to prevent the side effects of wastewater irrigation and the further studies on these topics were proposed.

Organic contamination of groundwater is being paid more and more attention in many counties including China.In this paper,the situation of groundwater organic contamination,the general source of organic contaminants,the processes and factors influencing the migration and transform of organic contaminants, the natural attenuation and active remedial technique are reviewed.Finally,problems needing attention and research direction in this field are put forward.