Emergent effects of heavy metal pollution at a population level: Littorina brevicula a study case

Changes in genetic variability and allele frequency can be responses from natural populations when encountering a novel contaminated environment. The genetic diversity and population structuring of natural populations of the gastropod Littorina brevicula from heavy-metal polluted and unpolluted environments along the southeast coast of Korea were examined using two mtDNA markers, cyt b and ND6. This study applied a nested clade analysis to test the existence of structuring association of haplotype distribution with environments (polluted and unpolluted). No genetic differences within cyt b mtDNA were detected between environments. On the other hand, differences in population haplotype diversity and structuring were found within ND6 mtDNA between polluted and unpolluted environments. The ND6-mtDNA haplotype (=genetic) diversity was significant lower in polluted environments. This decreased genetic diversity along with differences in the haplotype distribution within heavy-metal polluted environments compared to those unpolluted ones stand out as emergent effects from pollution at a population level. In this study, we propose the use of different approaches, such as the NCA, that takes into account the rare haplotypes, when assessing the effects of pollution on population genetic structuring.     

Environmental pollution and natural populations: a biomarkers case study from the Iberian Atlantic coast

The degradation of estuaries is a result of human activities which overloads the environment with substances of both industrial and/or natural origins. Bioindicators have been consistently used to interpret effects of contaminants in the environment. In this study, the use of biomarkers (particular measurable characteristics of a bioindicator organism) was used to evaluate the contamination by xenobiotics of Crangon crangon natural populations. The central aim was to evaluate the capability of a battery of biomarkers to discriminate sites with different types of contamination. The activity of the enzymes cholinesterases (ChE), lactate dehydrogenase (LDH) and glutathione S-transferases (GST) were used as biomarkers. In addition, the ChE form(s) present in the cephalotorax of C. crangon were characterised. Organisms were seasonally sampled from winter 2001/2002 to autumn of 2002, at "reference" sites and at sites that receive agricultural, industrial and/or urban effluents. Results obtained in the characterisation of ChE with different substrates and selective inhibitors demonstrate that the form of ChE present in the cephalotorax of C. crangon shows proprieties of vertebrates' AChE and therefore it may be classified as true AChE-like ChE. The battery of biomarkers exhibited seasonal and local variations, apparently related to agricultural, industrial or urban effluent contamination. The tested biomarkers proved to be able to discriminate sources of environmental contamination, and confirms C. crangon as a sensitive species suitable to be used as a bioindicator.     

Catchment-scale vulnerability assessment of groundwater pollution from diffuse sources using the DRASTIC method: a case study

Abstract

The catchment-scale groundwater vulnerability assessment that delineates zones representing different levels of groundwater susceptibility to contaminants from diffuse agricultural sources has become an important element in groundwater pollution prevention for the implementation of the EU Water Framework Directive (WFD). This paper evaluates the DRASTIC method using an ArcGIS platform for assessing groundwater vulnerability in the Upper Bann catchment, Northern Ireland. Groundwater vulnerability maps of both general pollutants and pesticides in the study area were generated by using data on the factors depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone, and hydraulic conductivity, as defined in DRASTIC. The mountain areas in the study area have “high” (in 4.5% of the study area) or “moderate” (in 25.5%) vulnerability for general pollutants due to high rainfall, net recharge and soil permeability. However, by considering the diffuse agricultural sources, the mountain areas are actually at low groundwater pollution risk. The results of overlaying the maps of land use and the groundwater vulnerability are closer to the reality. This study shows that the DRASTIC method is helpful for guiding the prevention practices of groundwater pollution at the catchment scale in the UK.

Citation Yang, Y. S. & Wang, L. (2010 Yang, Y. S. and Wang, L. 2010. A review of modelling tools for implementation of the EU Water Framework Directive in handling diffuse water pollution. Water Resour. Manage., 24: 1819–1843.  [Google Scholar]) Catchment scale vulnerability assessment of groundwater pollution from diffuse sources using the DRASTIC method: a case study. Hydrol. Sci. J. 55(7), 1206–1216.     

How natural remanent magnetization of basaltic units can dominate the reduced to pole magnetic value: A case study from the Faroe Islands

Early attempts to utilize magnetic data to understand the volcanic and subvolcanic succession on the Faroese Continental Shelf have shown that conventional interpretation and modelling of magnetic data from this area leads to ambiguous results. Interpretation of the aeromagnetic data on the Faroese Continental Shelf shows that some previously identified basement highs coincide with reduced-to-pole magnetic highs, whereas others coincide with negative or mixed magnetic features. Similarly, igneous centres are characterized by different polarity magnetic anomalies. Palaeomagnetic analysis of the onshore volcanic succession has demonstrated that the thermoremanent magnetization of the basaltic lavas is stronger than the induced magnetism, and both reversely and normally magnetized units are present. We have tested this with 2½D profile modelling using the palaeomagnetic information to correlate high-amplitude magnetic anomalies with basalt successions containing changes in magnetic polarity. This approach has enabled us to map the termination of the differently magnetized units offshore and thereby extend the mapping of the Faroe Island Basalt Group on the Faroese Platform and into adjacent areas.     

Dependence of air pollution on meteorological conditions based on magnetic susceptibility measurements: a case study from Warsaw

This study reports systematic analysis of air pollution concentration by particulate matter (PM) in relation to annual changes of metrological conditions. The concentration of PM collected on filters was evaluated by magnetic properties. Long series of filters collected during 1977, 1980, 1981 and 1985 in Warsaw have been used for measurement. Such long time series allowed a better determination of correlation between seasonal susceptibility changes and meteorological conditions and to verify the repeatability of annual behavior. The magnetic susceptibility normalized by mass (??) has been used as a proxy of pollution. Monthly variations of ?? (??_m) demonstrated slow and small seasonal changes disturbed by quick, high peaks. The filters with high susceptibilities contain a mixture of magnetic single and multidomain grains which is characteristic for anthropogenic pollution, with the frequency-dependent susceptibility ??_fd being less than 4%. The low susceptibility samples are characterized by admixture of small amount of pseudo-single domain (PSD) and possible small amount of superparamagnetic (SP) grains. Detailed analysis of reduced mean monthly susceptibility ??_R revealed that temperature and absolute humidity correlate positively in cold period of year and negatively in warm months. The linear correlation coefficients range from 0.7 to 0.9 and from 0.3 to 0.4 for negative and positive linear correlation, respectively. The dispersion of pollutants in a city depends on the way of ventilation. The big cities like Warsaw are urban heat islands which act the most effective way for the warm period and for the cold time. The correlation of ??_R with absolute humidity is similar to that for temperature but for different reasons. The presence of big amount of water vapor particles in the atmosphere can favor the adhesion of smaller ferromagnetic grains to their surface which can accelerate the process of falling down of such agglomerates. Such a process can take place during wintertime. We do not observe clear correlation between ??_R and precipitation.     

HAPEX-Sahel: a large-scale study of land-atmosphere interactions in the semi-arid tropics

The Hydrologic Atmospheric Pilot EXperiment in the Sahel (HAPEX-Sahel) was carried out in Niger, West Africa, during 1991 - 1992, with an intensive observation period (IOP) in August - October 1992. It aims at improving the parameterization of land surface atmosphere interactions at the Global Circulation Model (GCM) gridbox scale. The experiment combines remote sensing and ground based measurements with hydrological and meteorological modelling to develop aggregation techniques for use in large scale estimates of the hydrological and meteorological behaviour of large areas in the Sahel. The experimental strategy consisted of a period of intensive measurements during the transition period of the rainy to the dry season, backed up by a series of long term measurements in a 1^ by 1^ square in Niger. Three “supersites” were instrumented with a variety of hydrological and (micro) meteorological equipment to provide detailed information on the surface energy exchange at the local scale. Boundary layer measurements and aircraft measurements were used to provide information at scales of 100 - 500 km². All relevant remote sensing images were obtained for this period. This programme of measurements is now being analyzed and an extensive modelling programme is under way to aggregate the information at all scales up to the GCM grid box scale. The experimental strategy and some preliminary results of the IOP are described.     

Risks of airborne pollution accidents in a major conurbation: case study of Zhangjiakou,a host city for the 2022 Winter Olympics

The number of airborne pollution accidents is second only to that of water-borne pollution accidents, in recorded environmental disasters. Acute casualties and public health costs have prompted many airborne pollution risk analyses. To date, few assessment methods have been carried out at regional-scale to quantify acute airborne pollution risk. Herein, a Hybrid Simulation and Risk Analysis approach, involving a systematic combination of simulation, risk ranking, and standardized analysis, is proposed at regional scale. Gaussian and heavy-gas models are utilized in the simulation process, and acute exposure limits preferentially adopted in the risk analysis. The case study shows that 34 of 243 townships in Zhangjiakou City of north China, one of the twin cities selected to host the 2022 Winter Olympics, are threatened by airborne risk sources. It is found that the accidental air pollution risk is comparatively higher in the Xuanhua and Wanquan conurbations. High-risk chemical enterprises (312–432 risk scores) are mostly located near urban areas with high population density where many people are vulnerable receptors to potential air pollution accidents. The resulting risk map indicates that acute airborne pollution from Zhangjiakou would not be a threat either to the proposed Olympic site at Chongli or to downwind Beijing.     

Ficus benjamina leaves as indicator of atmospheric pollution: a reconaissance study

We present a diagnostic study to evaluate the suitability of Ficus benjamina tree leaves as a captor of heavy metal particles from atmospheric dusts in urban areas. Leaf samples were taken at 16 localities within three areas in Morelia, state of Michoacán (Mexico??s medium size city, 830000 inhabitants). Measurements of magnetic susceptibility were conducted to determine the magnetic enhancement using samples from green, relatively unpolluted area, as a reference. The samples collected at areas with heavy traffic (main avenues) yielded values almost ten times higher than the values obtained for the unpolluted reference. Isothermal Remanent Magnetization curves are proportional to the degree of pollution. Associations of almost pure magnetite with heavy metals were revealed by scanning electron microscope.     

The gutenberg-richter law for earthquakes in air pollution episodes: A case study for Athens, Greece

The main aim of this study is to investigate whether the main components of the photochemical smog episodes over megacities obey the Gaussian distribution or do they follow the distribution of the Gutenberg-Richter law. To this end, a case study has been implemented for Athens, Greece, which is among the most densely populated capitals in the middle latitudes of the Northern Hemisphere. The data employed are hourly mean values of surface ozone and nitrogen dioxide concentrations collected by the National Air Pollution Monitoring Network during the period 1988–2008. The results obtained show that the surface ozone and nitrogen dioxide concentrations obey the Gutenberg-Richter law, while their extreme values follow the Generalized Pareto distribution. This finding is important for current efforts to reliably forecast the air pollutants concentrations and to quantify their contribution to climate change. Finally, the plausible mechanisms involved in air pollution dynamics leading to the above-mentioned behaviour are also discussed, assuming the air pollution system governed by non-linear processes.     

Real-time multipurpose reservoir operation: a case study

Abstract

A real-time operational methodology has been developed for multipurpose reservoir operation for irrigation and hydropower generation with application to the Bhadra reservoir system in the state of Karnataka, India. The methodology consists of three phases of computer modelling. In the first phase, the optimal release policy for a given initial storage and inflow is determined using a stochastic dynamic programming (SDP) model. Streamflow forecasting using an adaptive AutoRegressive Integrated Moving Average (ARIMA) model constitutes the second phase. A real-time simulation model is developed in the third phase using the forecast inflows of phase 2 and the operating policy of phase 1. A comparison of the optimal monthly real-time operation with the historical operation demonstrates the relevance, applicability and the relative advantage of the proposed methodology.     

Verification of landslide susceptibility mapping: a case study

A methodology is proposed for mapping susceptibility to landsliding and validating the results. Heavy rains in late 1996 and early 1997 led to a large number of landslids in the Rute sector (Córdoba, Southern Spain), where landslide susceptibility mapping had previously been carried out using a ‘matrix’ method developed with a Geographical Information System (GIS). Analysis of the distribution of the new landslides (or reactivated earlier ones) enabled the methodology to be validated by calculating association coefficients and determining the closeness of the match between subsequent field evidence and the previously defined susceptibility levels. From the data obtained, it can be concluded that the susceptibility mapping effectively explained the spatial distribution of landslides, thus providing valuable information on stability conditions over a widespread area. Copyright © 1999 John Wiley & Sons, Ltd.     

Vehicle-derived emissions and pollution on the road autovia 2 investigated by rock-magnetic parameters: A case study from Argentina

In this work, we carried out a preliminary study of traffic-derived pollutants from primary sources (vehicles), and on roads (paved area), road borders and surroundings areas. The study is focussed on the identification, distribution and concentration of pollutants and magnetic carriers. Magnetic parameters and their analyses suggest that the magnetic signal of vehicle-derived emissions is controlled by a magnetite-like phase. Magnetic grain size estimations reveal the presence of fine particles (0.1–5 μm) that can be inhaled and therefore are dangerous to human health. Magnetic susceptibility results (about 175 × 10⁻⁵ SI) show a higher magnetic concentration — magnetic enhancement — in the central area of the tollbooth line that is related to higher traffic. In addition, magnetic susceptibility was computed on several roadside soils along a length of 120 km and used to generate a 2-D contour map, which shows higher magnetic values (100–200 10⁻⁵ SI) near the edge of the road. The observed distribution of magnetic values indicates that magnetic particles emitted by vehicles are accumulated and mainly concentrated within a distance of several meters (1–2 m) from the edge of the road. In consequence, the magnetic susceptibility parameter seems to be a suitable indicator of traffic-related pollution. Non-magnetic studies show an enrichment of some trace elements, such as Ba, Cr, Cu, Zn and Pb, that are associated with traffic pollution. Furthermore, statistical correlations between the content of toxic trace metals and magnetic variables support the use of magnetic parameters as potential proxies for traffic-related pollution in this study area.     

Soil creep: problems raised by a 23 year study in Australia

In October 1965 and February 1966, 55 Young-pits were installed in tropical Northern Territory (NT) and temperate New South Wales (NSW). Pits were monitored in 1968, 1971 and 1974; also, for the NT only, in 1988. In each region, half of the pits are on weathered granite, and half on sandstone. Local relief is 30m or less, and slopes are up to 20°. Annual rainfall is evenly distributed in the NSW sites (800 mm a⁻¹), but is confined to the five to six month wet season in NT (1200 mm a⁻¹). Six pits suffered external disturbance and so were not analysed. Analysis of 160 rods in 49 undisturbed pits shows: (1) vectorial movement generally not downslope parallel to the ground surface, but dominated by a vertically downward component; (2) significant uphill and vertically upward components of movement for many rods; (3) a weak correlation between total movement and sine of slope; (4) rapid movement during 1965-68, and slow movement thereafter; (5) significantly higher creep rates on the NT granites than on all other sites, perhaps because mound-building termites are especially active there. We conclude that our data do not support soil creep models which assume that all movement is downslope and slope-parallel. Repeated long-term measurements are essential to distinguish long-term creep rates from the short-term effects of disturbance. Copyright © 1999 John Wiley & Sons, Ltd.     

基于水质荧光指纹法的湖泊污染溯源研究——以太湖流域滆湖为例

随着社会经济和城市化进程的快速发展,湖泊水环境污染问题日益突出,加剧了湖泊原有功能的退化和丧失,因此污染治理成为了湖泊功能恢复和可持续发挥的必要条件,但如何实现污染精准溯源又是污染治理的重要前提。为此,本文以太湖流域滆湖为例,采用一种新兴技术——水质荧光指纹法开展湖泊污染溯源。于2021年累计采集滆湖周边70个农业、13个生活、3个企业排口的瞬时出水构建污染源荧光指纹库,连续12个月采集滆湖湖体8个样点水样分析水体荧光组分。通过平行因子分析共解析出4种污染源指纹和滆湖5种水体组分,经荧光相似度(塔克同余系数)分析进一步明确滆湖主要受到种植业面源、生活源和工业源的影响。此外,荧光强度与叶绿素a浓度和藻密度的强相关性表明藻类繁殖活动也会影响滆湖。从不同污染源对滆湖的时空影响特征来看,种植业面源主要在春、夏季影响西部、中部水域,生活源主要在夏、冬季影响西部、北部水域,工业源主要在特定月份(3 4月、10 12月)影响西部水域,藻类繁殖活动主要在夏季影响湖体。通过荧光组分与水质参数的时空相关性分析得到农业源和总磷、总氮,生活源和氨氮、有机物参数(BOD₅、COD_...     

江湖连通方案的最佳引水流量研究——以湖北磁湖为例

江湖连通工程能够在短期内达到改善湖泊水质的目的,在国内外得到了广泛应用.但是,在保证改善效果的前提下,如何尽量节约投资和运行费用、确定合理的引水流量尚未得到充分的研究.以水环境质量改善后降低的污水处理费用作为工程经济效益指标,提出了成本和效益评估方法用以评估计算引水流量与工程经济效益、工程运行成本、净效益的定量关系,最后分析得到合理的引水流量范围和最佳引水流量,并利用基于DEM的二维水量水质数学模型来模拟分析水质改善效果.该方法应用于湖北黄石磁湖,在其水体连通方案的基础上,模拟8种不同引水流量工况,分析引水流量与净效益的关系曲线,计算得到最佳引水流量.结果表明:随着引水流量的增加,净效益先增大后减小,每次引水的净效益最大值为4.05万元,相对应的最佳引水流量为10.62 m3/s.本研究为磁湖及其它类似水域的水污染治理和成本控制提供了科学的参考依据.     

岩溶峡谷型水库沉积物磷形态分布及污染评价——以万峰水库为例

开展岩溶峡谷型水库沉积物磷形态分布、影响因素及污染风险研究,对区域水环境治理和水生态系统管理具有重要意义。研究选取典型岩溶峡谷型水库——万峰水库为研究对象,在分析沉积物磷形态分布特征基础上,识别沉积物磷形态空间分异影响因素并进行磷污染评价。结果表明,(1)沉积物总磷(TP)含量为79.37~438.04 mg/kg,无机磷(IP)占比为73.26%~78.84%,IP是沉积物磷的主要赋存形态。铁铝结合态无机磷(Fe/Al-Pi)含量为16.86 ~91.82 mg/kg,是IP的主要赋存形态;弱吸附态有机磷(H₂O-Po)含量为0.27~8.03 mg/kg,是有机磷(OP)的主要赋存形态。(2)残渣态磷(Res-P)、弱吸附态无机磷(H₂O-Pi)、钙结合态无机磷(Ca-Pi)、潜在活性无机磷(NaHCO₃-Pi)、Fe/Al-Pi是TP空间分异的主要影响因素。沉积物的厚度对于TP具有多重作用,与其他因素的共同作用影响显著。(3)生物有效性磷(BAP)含量为66.97~201.46 mg/kg,占TP的55.6%~59.6%;磷污染指数均值为0.53,生物有效性指数均值为0.81。表明沉积物磷污染程度整体为轻度污染,但仍存在潜在的内源磷污染上覆水体风险。建议岩溶峡谷型水库在控制外源磷输入的同时,也应加强对内源磷的管理,以降低内源磷释放污染上覆水体的风险。     

MELIMEX,an experimental heavy metal pollution study: Vertical mixing in a large limno-corral

In a limno-corral (diameter 12 m, depth to sediments 10 m), located in Baldeggersee (Switzerland), vertical mixing has been measured during more than one year and compared to the conditions in the open lake (maximum depth 65 m, surface area 5.3 km²). The temperature method by McEwen and Hutchinson yields K_z values between 5×10⁻² cm²s⁻¹ at the upper boundary of the thermocline and 2×10⁻³ cm²s⁻¹ at the bottom, a value near the molecular diffusion of heat at 4°C (1.36×10⁻³ cm²s⁻¹). K_z calculated from profiles of excess radon-222 generally agree with those from the temperature data. Compared to the open lake, the corral has a more shallow epilimnion. However, during calm meteorological conditions, vertical mixing in the upper 10 m is similar outside and inside the corral. Supported by the Swiss National Science Foundation within the framework for its National Research Program on ‘Lake Currents.’