Application of statistical methods to study seasonal variation in the mine contaminants in soil and groundwater of Goa, India   总被引：1，自引：0，他引：1  

D. S. Ratha  G. Venkataraman 《Environmental Geology》1997,29(3-4):253-262

 Soil and groundwater samples were collected during two seasons, premonsoon (April 1990) and postmonsoon (December 1990), and analyzed for major elements (Na, Mg, Al, Si, P, K, Ca, Ti, Mn and Fe), trace elements (Ni, Pb, Co, Cr and Zn) and water parameters (pH, conductivity, acidity, alkalinity, hardness, Cl and SO₄). All the data were subjected to linear discriminant analysis and partial correlation analysis in order to understand the seasonal variation in the data. It was observed from the Mahalanobis generalized distance that in both soil and groundwater samples there was a large difference in the concentration level of premonsoon and postmonsoon data. Linear discriminant functions were calculated to distinguish between premonsoon and postmonsoon samples. From the partial correlation coefficient analysis of soil samples, dominance of chemical weathering and precipitation of atmospheric fallout during monsoon were inferred. In the case of the water samples, high conductivity and high hardness in the postmonsoon samples as well as atmospheric fallout of Pb and Ni during the premonsoon period was suggested from partial correlation of water samples. Received: 19 September 1995 · Accepted: 12 December 1995  相似文献   

Cd, Cr, Cu, Ni and Pb in the water column and sediments of the Ob-Irtysh Rivers, Russia     

S. BradleyMoran  Wendy L. Woods 《Marine pollution bulletin》1997,35(7-12):270-279

Concentrations of Cd, Cr, Cu, Ni and Pb were determined in filtered water, suspended particulate matter, and bottom sediments from a 2000 km section of the Ob and Irtysh Rivers. Dissolved Cd, Cr, Cu and Ni concentrations are similar to, or higher than, results from other Russian Arctic and large world river-estuaries. Concentrations of Cd, Cr, Cu, Ni and Pb in suspended particulate matter are generally comparable to results from other Russian Arctic and large world rivers and estuaries. Comparison of trace metal ratios in crustal material and suspended particulate matter and bottom sediment suggests that the source of Cr, Cu and Ni is continental weathering. Particulate Cd and Pb are elevated relative to their crustal abundance, suggesting a source of these metals to the Ob-Irtysh in addition to continental weathering.  相似文献   

The impacts of pasture- and manure-spreading on microbial groundwater quality in carbonate aquifers   总被引：2，自引：0，他引：2  

Celico  F.  Musilli  I.  Naclerio  G. 《Environmental Geology》2004,46(2):233-236

Hydrogeological and microbiological research is in progress to analyze the interaction between groundwater and microbial pollutants, produced by pasture and/or manure spreading, in the areas of different carbonate aquifers of southern Italy. Several springs and wells were studied, and the precipitation, the discharge, the groundwater level and the classic microbial indicators of pollution were monitored weekly or daily. The experimental results show that the pasture and the manure spreading produced microbial contamination of the groundwater, even if runoff infiltration in swallow holes does not exist. The time dependence of microbial contamination shows a series of peaks irregularly distributed, related to the precipitation that produce effective infiltration.  相似文献   

Characteristics of distribution and transport of petroleum contaminants in fracture-karst water in Zibo Area, Shandong Province, China   总被引：8，自引：0，他引：8  

ZHU Xueyu  LIU Jianli  ZHU Junjie  CHEN Yudao 《中国科学D辑(英文版)》2000,43(2):141-150

Fracture-karst water is an important water resource for the water supply in North China. Petroleum contamination is one of the most problematic types of the groundwater pollution. The characteristics of distribution and transport of the petroleum contaminants in fracture-karst water are different from those in porous water. The flow velocity of fracture-karst water is much faster than the velocity of porous water on an average. Therefore, contaminant transport in fracture-karst water is an absolute advection-dominated problem. The plume of the petroleum contamination may extend to several kilometers from pollution sources. It was not caused by the oil pool floating on the water table but by the oil components dissolved and scattered in groundwater. The distribution of the petroleum contaminants over space are concentrated in the strong conductive zone on the plane. On the vertical section the highest concentration of the oil contaminants appeared in the strata where the contamination sources were located. The concentrations of the oil contaminants in wells changed greatly over time. Therefore, the curves of concentration versus time fluctuated greatly. The reasons are as follows. (a) Fracture-karst water has a very great velocity. (b) Local flow fields which were caused by pumping and stoppage in some wells changed frequently. (c) In fracture-karst aquifer the transport channels are complicated. (d) Residual oil in vadose zone was leached after rainfall. It is of great practical value for the control and remediation of petroleum contamination in fracture-karst aquifer to understand those characteristics.  相似文献   

世界主要国家碳排放强度历史变化趋势及相关关系研究   总被引：4，自引：1，他引：3  

张志强  曾静静  曲建升 《地球科学进展》2011,26(8):859-869

减少人类活动的温室气体特别是CO2排放量是国际社会已普遍达成共识的应对气候变暖的根本性途径。研究各国经济活动的碳排放强度的变化历史,可以为预测各国未来的碳排放强度趋势、制定未来的碳排放强度降低目标提供科学依据。利用美国橡树岭国家实验室CO2信息分析中心（CDIAC）的CO2排放数据、《世界人口、国内生产总值和人均国内生...  相似文献   

SARS in Singapore—challenges of a global health threat to local institutions     

Giok Ling Ooi  Kai Hong Phua 《Natural Hazards》2009,48(3):317-327

SARS (Severe Acute Respiratory Syndrome) has been declared by WHO (World Health Organisation) as a global health threat. Within a period of four to five months in 2003, the disease infected some 8,000 people in more than 25 countries and left 774 dead. The many studies that have been done on the spread of SARS in Asia as well as countries as far flung as Germany and Canada have focused on the global dimension of the infectious disease as well as the speed of its spread upon emergence in southern China and then Hong Kong. Less attention has been paid to its spatial distribution at the national and local scales. This discussion focuses on the spread of SARS at the national and local spatial scales. In the process, the study presents the management of a hazard, in this case, an emerging infectious disease by national health care institutions such as the hospitals that ultimately proved to have been wholly unprepared for coping with at least the health aspects of the outcome of a globalised national agenda for growth and economic progress.  相似文献   

渤海滩涂湿地沉积物胶体对石油污染物的吸附特征   总被引：1，自引：0，他引：1  

李海明  马杰  顾晓明  郑西来 《湿地科学》2008,6(2)

为了研究滩涂湿地沉积物胶体对石油污染物的吸附作用,根据渤海天津段滩涂湿地沉积物的结构和组成,选择代表性沉积物提取胶体,对胶体的粒径、ζ电位、电泳淌度进行了表征,系统测定胶体对可溶性油吸附的动力学曲线和吸附等温线。结果表明,滩涂湿地沉积物胶体平均粒径为345.04nm;ζ电位、淌度中值分别为-0.47mV、-0.03μs-1V-1cm;交换吸附动力学模式适用于滩涂沉积物胶体对可溶性油的吸附作用,其吸附平衡时间约为20~24h,胶体对可溶性油吸附速率常数为9.434L/(g·h);胶体对可溶性油的等温吸附线为直线型,当水相中石油烃浓度低于某一值时,胶体不但不吸附溶液中的石油烃,反而使胶体中的残留石油烃释放出来。  相似文献   

Concentration and distribution of hydrophobic organic contaminants and metals in the estuaries of Ukraine     

Robert M. Burgess  Anna V. Terletskaya  Mark Povolotskii  Tatiyana A. Bogoslavskaya  Tatiyana V. Vorobyova  Artem Lyashenko 《Marine pollution bulletin》2009,58(8):1103-1115

In this study of Ukrainian estuaries, sediments and tissues from the Dnieper and Boh estuaries and Danube Delta on the mainland, Sevastopol and Balaklava Bays on the Crimean Peninsula, and coastal Black Sea along the Crimean Peninsula were collected in 2006. Contaminant analyses included several metals, the hydrophobic organic chemicals (HOCs) polychlorinated biphenyls, several chlorinated pesticides, and polycyclic aromatic hydrocarbons. When compared to estuarine sediments globally, the Ukrainian sediments were found to be moderately contaminated. However, several metals, especially mercury, were often shown to be elevated in the tissues of the Ukrainian organisms in comparison to organisms from other estuarine locations. Sediment quality guidelines indicate some of the estuarine sediments could be sufficiently contaminated to cause adverse toxicological effects. This investigation represents the first extensive study of HOC and metal baseline concentrations and distributions in Ukrainian estuaries and seeks to characterize exposures to aquatic organisms living in these systems.  相似文献   

Design and Development of Onsite Biofilter Unit for Effective Remediation of Contaminants from Wastewater     

Simranjeet Singh  Praveen C Ramamurthy  Daljeet Singh Dhanjal  Sikander Rana  Deepika Bhatia  Ramesh Kanwar  Neeta Raj Sharma  Joginder Singh 《洁净——土壤、空气、水》2023,51(3):2100396

Agricultural biomass is proven ecofriendly and effective adsorbent for the remediation of contaminants from wastewater. Here, rice husk biochar (600 °C) prepared by a one-step pyrolysis method is used for the remediation of different contaminants in real samples. An onsite biofilter unit is fabricated with parallel trenches of different layers of coconut coir and biochar and is used as a biofiltration unit. The efficiency of the designed unit is assessed for the removal of different contaminants in pilot-scale experiments. Results show that removal efficiency varies from metal to metal and ranges from 5.52% to 90.76% using the biofilter unit. Fourier-transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray analysis, carbon, hydrogen, nitrogen, and Brunauer–Emmett–Teller analysis before and after the adsorption represent the changes in the morphology and surface functionalization of the biochar. Results indicate that the designed biofilter unit could also be used as a promising agent for the remediation of pharmaceutical and other emerging contaminants from wastewater.  相似文献   

高密度蓝藻厌氧分解过程与污染物释放实验研究   总被引：18，自引：6，他引：12  

尚丽霞  柯凡  李文朝  徐宪根  宋媛媛  冯慕华 《湖泊科学》2013,25(1):47-54

采用批次培养实验模拟高密度蓝藻堆积发生的厌氧分解过程,分析蓝藻的分解速率及污染物释放规律.厌氧分解实验中,设置三组蓝藻初始密度分别为2.23×1012、1.19×1013、4.47×1013cells/L,得到叶绿素a的分解速率常数分别为0.074、0.133、0.081 d-1.蓝藻厌氧分解过程中水体呈酸性,电导率呈上升趋势,最高值为949μS/cm.化学需氧量持续升高,而UV254值先升高后降低,说明水体中有机物浓度增大,并逐渐由大分子分解为小分子有机物.蓝藻厌氧分解释放出大量溶解态氮、磷,溶解态有机氮逐渐被降解为无机氮,铵态氮含量占90%以上.研究表明,高密度蓝藻堆积发生厌氧分解可释放大量有机物和溶解态营养盐至水体中,并且随着蓝藻密度升高,污染物释放强度增大.因此水华期间应及时打捞蓝藻,以避免蓝藻大量堆积死亡导致水源区水质下降并影响自来水出水质量.  相似文献