Mobility of heavy metals as a function of pH of samples from an overbank sediment profile contaminated by mining activities     

Hans-Eike Gbler 《Journal of Geochemical Exploration》1997,58(2-3)

Parts of the flood plains north of the Harz Mountains are contaminated with heavy metals, such as Pb, Cu, Zn and Cd derived from mining, which has been carried out in the Harz Mts. since the Middle Ages. It is important to know the mobility of the heavy metals in these overbank sediments in order to estimate the danger to the environment arising from this source. This paper deals with the effect of pH on heavy-metal mobility, using a constant-pH method. The investigations were carried out on an overbank sediment profile near Salzgitter Bad, north of the Harz Mts. The mobility of the heavy metals in the overbank sediment profile is described as a function of pH and depth. Besides the mobile heavy-metal fraction at a certain pH, the buffering capacity of the sediment at this pH must be taken into consideration. The different layers of the overbank sediment profile show distinct differences in buffering capacity and a natural pH harrier could be identified in the upper part of the profile. Therefore, to avoid increasing heavy-metal mobility the natural layering of the overbank sediment profile should not be disturbed. Two different kinds of desorption experiments at constant pH are also discussed, as well as the conversion of the heavy-metal species in the ore minerals into the species in the sediment.  相似文献   

高坝泄流雾化环境污染原体观测研究          下载免费PDF全文

吴福生  程和森 《水科学进展》1997,8(2):189-196

高水头大流量的泄水建筑物泄流时产生严重泄流雾化对工程和环境造成污染,是必须考虑的重要问题。介绍了泄流雾化观测的新技术及其原理,包括:用立体摄影测量方法观测雾化流运动扩散的形态范围;用放射性同位素测量典型区域内泄流雾化浓度,并配合以雨量简测量典型范围内泄流雾化降雨强度等。并以漫湾水电站原体观测为实例,介绍了实施方法和效果。  相似文献   

垃圾和垃圾学──一门新兴科学的出现及其对中国固体废物处理事业的意义     

郑毅 《吉林大学学报(地球科学版)》1996,(1)

垃圾产生于社会的每一个角落，垃圾也反映了人类生活的各个方面。可是，直至最近，社会依然极少理会垃圾中真正蕴藏着些什么，以及垃圾能够告诉我们些什么。１９７３年美国图森市亚利桑那大学威廉·拉舍基博士（ＷｉｌｌｉａｍＬＲａｔｈｊｅ）及其同事们所建立并发展的垃级计划，标志着一门新科学──垃圾学的兴起，即垃圾的系统研究、垃圾产生、运移、利用和处置的机理以及相关的社会经济和环境问题。美国和其它少数国家的垃圾学研究所揭示的各种事实、定律和原理，正划时代地碰击着现代社会、社会心理学、市场和许多其它领域，大量的城市固体废物不仅意味着自然资源的巨大浪费，而且垃圾处理，无论焚化或者填埋，都对环境构成了严重污染的威胁，尤其是对地下水资源。垃圾的管理、再循环和处置费用是昂贵的，而且总是受到错综复杂的社会和法律冲突的挑战，纽约和美国东部其它人口稠密地区所面临的严峻形势就是最好的例证，解决现今进退维谷的垃圾问题，需要包括技术的、社会的、环境的、经济的、政治的、法律的和公共教育在内的多方面协作。中国正经历着令人振奋的经济发展时期。预计以现在的国民经济发展速度，以及因巨量人口而导致的社会消费的急剧增长，在未来１０～２０年内，很有可能导致严重的  相似文献   

中国长江主要灾害与整治     

徐学思  胡连英 《江苏地质》1996,20(1):18-23

由于江水和人类活动，引发长江崩塌、淤寒、洪涝和污染等灾害。研其原因主要为水动力改变；自然环境变化；人为破坏。整方案应采取治沙，营造“森林水库”；治水，按水动力学运动规律，用蓄、疏堵等手段综合治理；治污，要彻底根治污源；养殖，大力发展养殖业，促使生态平衡。  相似文献   

岩溶地下水集中开采区水质系统预测研究     

王伍军  鄢贵权 《物探化探计算技术》1997,19(4):337-342

在岩溶地区，地下水的超强度开采与工业“三废”及生活废弃物不合理的排放，造成了地下水较严重的污染。用动态系统方法建立的地下水污染时间序列递推预测模型，在岩溶地下水环境质量预测与管理方面都具有指导意义。  相似文献   

广州珠江西航道,流溪河有机污染特征与感潮作用   总被引：6，自引：3，他引：6  

王新明  闵育顺 《地球化学》1997,26(3):54-59

珠江西航道和流溪河在广州市区上游，为广州市主要水源区。由于感潮作用，受市区严重污染的水体因涨潮上溯而上游传输。严重影响上游水质。因此，弄清感潮作用对广州水源区水质的影响程度和范围，对水源保护与利用有重要意义。本研究从下游到上游，对水源区底泥中有机物特征进行了分析，结果表明：（１）从上游到上游，受感潮作用影响逐渐减小，污染程度逐渐减轻；（２）水源区有机物特征呈有规律变化。从靠近城市的下游到远离城市的  相似文献   

生活垃圾淋滤液组分的变化特征及其污染机理分析──以长春市为例   总被引：3，自引：0，他引：3  

郑德凤  赵勇胜  曹玉清 《吉林大学学报(地球科学版)》1997,(2)

利用室内模拟试验成果对长春市生活垃圾淋滤液的组分特征、变化规律及其对土壤、地下水的污染机理进行了分析；结合野外监测资料运用非确定性模型方法建立模拟模型，对淋滤液的污染组分进行趋势预测，为垃圾堆放场地的设计和垃圾污染的治理提供理论上的依据。同时为解决城市生活垃圾污染问题和寻找垃圾场地奠定了基础  相似文献   

VARIATION OF TOTAL OZONE IN LOWER LATITUDE AREA OF CHINA     

张秀年  常有礼  陈辉  郭世昌  孙正友 《热带气象学报(英文版)》2004,10(2):171-177

By using the observational O3 data of Kunming and Hong Kong during the period of 1997 – 2001, the paper studies the distribution and variation of total ozone in low latitude region of China. The study shows that the characteristics of variation in Kunm…  相似文献   

Assessment of Lichen Vitality During a Transplantation Experiment to a Polluted Site     

R. M. Godinho  M. C. Freitas  H. Th. Wolterbeek 《Journal of Atmospheric Chemistry》2004,49(1-3):355-361

The present work evaluates the stress effects in two epiphytic lichen species with different thallus morphology, the foliose Parmelia caperata and the fruticose Evernia prunastri, as resulting from transplanting from an unpolluted to an air-polluted area. Lichen samples were collected in Portugal in a clean area, during the spring 2003, and transplanted (1) to the same zone nearby and (2) to a polluted area as affected by an industrial complex. Transplant samples were taken periodically during four months in both places. At the same time lichen samples from the clean-air site native (in-situ) populations were also collected. For each sample were measured the chlorophyll content, the chlorophyll degradation and the cell membrane damage, the latter represented by leacheate conductivity. During the experiment the meteorological conditions were registered. The results indicate the absence of stress effects of transplanting as such, and suggest that leachate conductivity may be the more sensitive indicator of general lichen vitality.  相似文献   

Kinetics of the Gas-Phase Reactions of OH Radicals, NO3 Radicals and O3 with Three C7-Carbonyls Formed From The Atmospheric Reactions of Myrcene, Ocimene and Terpinolene     

Jillian Baker  Janet Arey  Roger Atkinson 《Journal of Atmospheric Chemistry》2004,48(3):241-260

Rate constants for the gas-phase reactions of OH radicals, NO₃ radicals and O₃ with the C₇-carbonyl compounds 4-methylenehex-5-enal [CH₂=CHC(=CH₂)CH₂CH₂CHO], (3Z)- and (3E)-4-methylhexa-3,5-dienal [CH₂=CHC(CH₃)=CHCH₂CHO] and 4-methylcyclohex-3-en-1-one, which are products of the atmospheric degradations of myrcene, Z- and E-ocimene and terpinolene, respectively, have been measured at 296 ± 2 K and atmospheric pressure of air using relative rate methods. The rate constants obtained (in cm³ molecule^–1 s^–1 units) were: for 4-methylenehex-5-enal, (1.55 ± 0.15) × 10^–10, (4.75 ± 0.35) × 10^–13 and (1.46 ± 0.12) × 10^–17 for the OH radical, NO₃ radical and O₃ reactions, respectively; for (3Z)-4-methylhexa-3,5-dienal: (1.61 ± 0.35) × 10^–10, (2.17 ± 0.30) × 10^–12, and (4.13 ± 0.81) × 10^–17 for the OH radical, NO₃ radical and O₃ reactions, respectively; for (3E)-4-methylhexa-3,5-dienal: (2.52 ± 0.65) × 10^–10, (1.75 ± 0.27) × 10^–12, and (5.36 ± 0.28) × 10^–17 for the OH radical, NO₃ radical and O₃ reactions, respectively; and for 4-methylcyclohex-3-en-1-one: (1.10 ± 0.19) × 10^–10, (1.81 ± 0.35) × 10^–12, and (6.98 ± 0.40) × 10^–17 for the OH radical, NO₃ radical and O₃ reactions, respectively. These carbonyl compounds are all reactive in the troposphere, with daytime reaction with the OH radical and nighttime reaction with the NO₃ radical being predicted to dominate as loss processes and with estimated lifetimes of about an hour or less.  相似文献