Coupling of multi-hydrochemical and statistical methods for identifying apparent background levels of major components and anthropogenic anomalous activities in shallow groundwater of the Liujiang Basin, China.

Natural background levels (NBLs) is a prerequisite for distinguishing anthropogenic groundwater pollution and judging the evolution of groundwater quality. However, due to regional differences of hydrogeochemitry and water-rock interaction, coupled with long-term anthropogenic activities, it is no longer accurate to assess NBLs with only statistical methods or without considering human impact. Herein, multi-hydrochemical and statistical methods were examined to identify apparent background levels and anthropogenic anomalous activities of shallow groundwater by selecting Liujiang Basin as a study area.

An experimental investigation on engineering properties of undisturbed loess under acid contamination.

Even though soil acidification can cause significant destabilizing effects on various geotechnical issues, studies have rarely been conducted to determine the influence of soil structure on the impact of acid-contaminated soil. The current work aims to understand the effect of acid fluids on engineering behavior of undisturbed loess through laboratory tests. The sampling site is in a typical region of Loess Plateau, China.

Sensitivity assessment of denitrifying bacteria against typical antibiotics in groundwater.

The effects of antibiotics on nitrate denitrification in groundwater have acquired growing concern. Denitrification is a microbially mediated process. The effects of antibiotics on denitrification were mainly reflected in denitrifying bacteria.

[Characteristics and Genesis of NO Type Water in Shallow Groundwater in Liujiang Basin].

In recent years, groundwater nitrate pollution has become more and more severe. Anthropogenic activities have become more significant, not only causing pollution, but also changing the hydrochemical type of groundwater and leading to the emergence of NO type groundwater. This study focuses on the Liujiang Basin.

[Geochemical Characteristics and Genesis Analyses of High-arsenic Groundwater in the Pearl River Delta].

To determine the main factors affecting the migration, enrichment, and sources of arsenic in the shallow groundwater of the Pearl River Delta (PRD), clustering analysis was used to partition the study area and then analyze the abnormal distribution of arsenic and groundwater storage environment in each part area based on the data obtained from the investigation of groundwater pollution in the PRD region. The results showed, in the study area, arsenic was mainly represented by As(Ⅲ), and its concentration ranged from under the detection limit to 560 μg·L. High-arsenic groundwater was mainly distributed in the plain area covered by Quaternary loose sediment, with the Shunde District in Foshan City having the highest, followed by Zhongshan City and central Guangzhou.

[Adsorption of Dissolved Organic Matter with Different Relative Molecular Masses on Inorganic Minerals and Its Influence on Carbamazepine Adsorption Behavior].

In this work, sorption experiments were conducted to understand the adsorption characteristics of dissolved organic matter (DOM) of different relative molecular masses on minerals and the effects of their interaction with PPCPs on the adsorption process. This study chose carbamazepine (CBZ) as the target pollutant, quartz sand as the inorganic mineral, and commercial humic acid (HA) as the DOM. We studied the structural characteristics of HA with different relative molecular masses and the impact of their interaction with CBZ on their adsorption based on dialysis experiments and infrared spectroscopy.

[Comparison of Identification Methods of Main Component Hydrochemical Anomalies in Groundwater: A Case Study of Liujiang Basin].

Identification of chemical composition anomalies in groundwater is an important basis for establishing groundwater background values and quantifying the degree of influence of human activities. The main component anomaly identification by five kinds of hydrochemical diagrams has achieved good results in the past. However, this method is too complex to be used widely.

[Screening Method of Priority Control Pollutants in Groundwater Based on Contamination Assessment].

Screening of priority control pollutants is an effective technical means for environmental management and environmental quality protection. Quick and efficient identification of pollutants is useful when attempting to prevent and control groundwater pollution. In order to explore a screening system for a set of priority pollutants that can be applied to regions with weak basic information, a screening method of priority pollutants based on contamination assessment is put forward in this paper.

[Comparison and Analysis of the Quantitative Methods for Pollutant Sources Load in Groundwater Contamination Risk Assessment].

Groundwater contamination risk assessment is an important basis for the protection of groundwater resources and the prevention and control of groundwater pollution. Its evaluation system is usually composed of three elements, which is vulnerability, pollutant source load and groundwater value. The pollutant source load plays an important role in risk assessment.

Cytotoxicity of chemical constituents from Torricellia tiliifolia DC. on Spodoptera litura (SL-1) cells.

In this study, we evaluated cytotoxicity of chemicals isolated from Torricellia tiliifolia DC. on Spodoptera litura (SL-1) cell line. Among the isolated compounds, 4-hydroxy-3-methoxycinnamaldehyde, 3,5-dimethoxy-4-hydroxycinnamaldehyde, and syringaresinol inhibited SL-1 cell survival in both dose- and time-dependent manners.

Identifying and assessing human activity impacts on groundwater quality through hydrogeochemical anomalies and NO, NH, and COD contamination: a case study of the Liujiang River Basin, Hebei Province, P.R. China.

In the face of rapid economic development and increasing human activity, the deterioration of groundwater quality has seriously affected the safety of the groundwater supply in eastern China. Identifying and assessing the impact of human activities is key to finding solutions to this problem. This study is an effort to scientifically and systematically identify and assess the influence of human activities on groundwater based on irregularities in hydrochemical properties and water contamination, which are considered to directly result from anthropogenic activity.

Occurrence, distribution, and attenuation of pharmaceuticals and personal care products in the riverside groundwater of the Beiyun River of Beijing, China.

This study investigated the occurrence, seasonal-spatial distribution characteristics, and attenuation process of 15 pharmaceuticals and personal care products (PPCPs) in riverside sections of Beiyun River of Beijing. The overall PPCP levels both in surface water and riverside groundwater were moderate on the global scale, and showed higher concentrations in the dry season mainly caused by water temperature variation. Caffeine (CF), carbamazepine (CBZ), metoprolol (MTP), N,N-diethyl-meta-toluamide (DEET), diclofenac (DF), bezafibrate (BF), and gemfibrozil (GF) were seven representative PPCPs, because the rest eight studied compounds occurred in low concentrations and less than 15% of the total concentration of PPCPs.

Abnormal pH elevation in the Chaobai River, a reclaimed water intake area.

The pH is a primary index reflecting water quality in rivers. The Jian River and Chaobai River are two reclaimed water intake areas which have elevated pH. This elevated pH has a marked effect on both the phytoplankton, species in water and vegetation on the shore.

[Simulation Experiment: Effect of Organic Colloid on Carbamazepine Transport in Porous Media].

The behavior of organic contaminants in subsoil can be affected by their interactions with organic colloids. In order to explore the impact of organic colloids on the mobility of emerging contaminants in porous media, especially pharmaceutical and personal care products (PPCPs), column experiment was conducted to investigate the migration behavior of target compound carbamazepine (CBZ). In the experiments, quartz sand, standard soil and natural field-collected soil were selected as three types of porous media respectively, and organic colloids were prepared with commercial humic acid.

[Distribution Characteristics and Potential Ecological Hazards Assessment of Soil Heavy Metals in Typical Soil Profiles in Southeast Suburb of Beijing].

To investigate the distribution characteristics and the potential ecology risk of different types of heavy metals, soil samples were collected from various stratigraphic sections in the southeastern suburb of Beijing, where soil heavy metal (Cu, Pb, Cr, As) contents were measured and analyzed using multivariate statistical analysis and the potential ecological risk index method. The results showed that the concentrations of the four heavy metals followed the order of Cr > Cu > As > Pb with variable coefficients ranging from 59.60% to 159.

[Distribution Characteristics of Fluoroquinolones Antibiotics in Surface Water and Groundwater from Typical Areas in A City].

In order to investigate the characteristics of 5 typical kinds of fluoroquinolones (FQs) pollution in waters from a city, surface water and groundwater samples from main drainage rivers and typical areas were collected, respectively. The conventional test and FQs concentrations analysis of the water samples were conducted. The results showed the concentration and composition of FQs in groundwater differed substantially from those in surface water.

[Forming mechanism of humic acid-kaolin complexes and the adsorption of trichloroethylene].

The interaction between soil organic components and mineral components was explored in this study. Humic acid and kaolin were used for the preparation of organic-mineral complexes with different contents of organic matter, for experimental study of the adsorption of trichloroethylene. The results showed that the adsorption of trichlorethylene fitted the Freundlich isotherm model.

[Comparative analysis of two different methods for risk assessment of groundwater pollution: a case study in Beijing plain].

Groundwater contamination risk assessment has important meaning to groundwater contamination prevention planning and groundwater exploitation potentiality. Recently, UN assessment system and WP assessment system have become the focuses of international research. In both systems, the assessment framework and indices were drawn from five aspects: intrinsic vulnerability, aquifer storage, groundwater quality, groundwater resource protection zone and contamination load.

[Contamination characteristics of fluoroquinolones in different kinds of soil profiles in Southeast suburb of Beijing].

Eighty-six soil samples were collected using Geoprobe soil sampler from 11 borehole profiles of Beijing Southeast suburb. The sampling sites could be divided into 8 kinds of landuse. Physical and chemical properties of samples were analyzed.

[Simulation of nitrate pollution in groundwater using pump-and treat optimization method].

To study the groundwater polluted by nitrate in a landfill site in Beijing, with the pump-and-treat technology, genetic algorithms (GA) and simulated annealing (SA) were used to optimize the cases of 18 planned pumping wells in the groundwater nitrate plume. The optimization method was run to determine the minimum total costs, as a result of the optimal number of wells with the optimal locations and pumping rates. The results of optimization showed that, both GA and SA optimization conditions could reach the desired results, which means that the concentration of nitrate could be reduced to 10 mg x L(-1) after 100 days pumping.

Surgical treatment for posterior rim separation of the lumbar and sacral vertebrae.

Objective: The posterior rim separation of the lumbar and sacral vertebrae has been ascribed to various mechanisms. The procedure of operative treatment is still controversial. The authors' objective was to study the therapeutic methods of posterior vertebral rim separation.

[Uncertainty analysis of groundwater protection and control zoning in Beijing plain].

Groundwater pollution prevention mapping has important meaning to groundwater protection, pollution prevention and effective management. A mapping method was built through combining groundwater pollution risk assessment, groundwater value and wellhead protection area zoning. To make the method more accurate, two series of uncertainty analysis were performed and discussed.

[Construction of groundwater contamination prevention mapping system].

Groundwater contamination prevention mapping is an important component of groundwater contamination geological survey and assessment work, which could provide the basis for making and implementing groundwater contamination prevention planning. A groundwater contamination prevention mapping system was constructed in view of the synthetic consideration on nature perspective derived from groundwater contamination sources and aquifer itself, social-economic perspective, policy perspective derived from outside. During the system construction process, analytic hierarchy process and relevant overlaying principles were used to couple groundwater contamination risk assessment, groundwater value as well as wellhead protection area zoning.

[Quantitative method of representative contaminants in groundwater pollution risk assessment].

In the light of the problem that stress vulnerability assessment in groundwater pollution risk assessment is lack of an effective quantitative system, a new system was proposed based on representative contaminants and corresponding emission quantities through the analysis of groundwater pollution sources. And quantitative method of the representative contaminants in this system was established by analyzing the three properties of representative contaminants and determining the research emphasis using analytic hierarchy process. The method had been applied to the assessment of Beijing groundwater pollution risk.

[Distribution of polycyclic aromatic hydrocarbons in soil profiles in southeast suburb of Beijing wastewater irrigation area].

3 borehole profiles samples were collected using Eijkelkamp soil sampler from the wastewater irrigation area of Beijing Southeast suburb. The soil samples were collected from surface to 5.5 m underground every 0.