首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
Within the last few years, uncleared solid wastes, in the form of heaps, have become a common sight in many Nigerian streets and open spaces. In order to assess the magnitudes of these wastes, a survey of selected 15 Nigerian cities was conducted for 2 months in 1982 with a team of 116 enumerators. It was found that the volumes of these uncleared wastes ranged from about 2 × 106 kg/yr to as high as 56 × 106 kg/yr in the cities studies. It was also found that the areas within a radius of 0.5 km of the city centres accounted for about 40% of these uncleared volumes of solid wastes.As distances increased from the city centres, the volumes of these wastes tended to decline. Therefore, it was determined that the main problem areas for uncleared solid wastes are in and around the city centres. These areas should demand special attention by city waste disposal agents.  相似文献   

2.
To evaluate the environmental impacts from large scale mercury mining (LSMM) and artisanal mercury mining (AMM), total mercury (THg) and methyl mercury (MeHg) were determined in mine waste, ambient air, stream water and soil samples collected from Wuchuan mercury (Hg) mining area, Guizhou, Southwestern China. Mine wastes from both LSMM and AMM contained high THg concentrations, which are important Hg contamination sources to the local environment. Total gaseous mercury (TGM) concentrations in the ambient air near AMM furnaces were highly elevated, which indicated that AMM retorting is a major source of Hg emission. THg concentrations in the stream water varied from 43 to 2100 ng/L, where the elevated values were mainly found in the vicinity of AMM and mine waste heaps of LSMM. Surface soils were seriously contaminated with Hg, and land using types and organic matter played an important role in accumulation and transportation of Hg in soil. The results indicated heavy Hg contaminations in the study area, which were resulted from both LSMM and AMM. The areas impacted by LSMM were concentrated in the historical mining and smelting facilities, while Hg pollution resulted from AMM can be distributed anywhere in the Hg mining area.  相似文献   

3.
The tannery industry in Hazaribag, which is one of the most polluted areas in Dhaka City, produces a huge quantity of wastes every day. Without treatment, these are discharged into the Buriganga River and pollute the surrounding environment. This article examines the impacts of tannery wastes on workers’ health and the environment in that particular area. As part of the methodology, a semi-structured interview was conducted in order to obtain quantitative data and 112 respondents were interviewed using purposive sampling. The findings of the study indicate that tannery wastes affect the environment severely, causing ecological imbalance and the spreading of different kinds of fatal and contagious disease among the tannery workers and other individuals. Moreover, the current waste management system of the Hazaribag tannery industries is very suspect due to outdated technology, defective drainage systems, lack of financial input, and the exploitative attitude of their owners. The findings also indicate that tannery workers are unaware of the effects of tannery waste as they choose not to wear personal protective equipment in the workplace. This empirical study helps policy makers implement appropriate measures to raise awareness, among both owners and workers, that can influence changes in the public’s attitude and reduce environmental pollution to a great extent. Although considerable research has been undertaken focusing on tannery waste impact assessment, less attention has been paid to the issue of workers’ health. Therefore, both governments and policy makers can benefit from the findings of this study.  相似文献   

4.
Sources of anthropogenic radionuclides in the environment: a review   总被引:1,自引:0,他引:1  
Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview on sources of anthropogenic radionuclides in the environment, as well as a brief discussion of salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current developments that have lead, or could potentially contribute, to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) uranium mining and milling; (5) commercial fuel reprocessing; (6) geological repository of high-level nuclear wastes that include radionuclides might be released in the future, and (7) nuclear accidents. Then, we briefly summarize the inventory of radionuclides 99Tc and 129I, as well as geochemical behavior for radionuclides 99Tc, 129I, and 237Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment; biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.  相似文献   

5.
铜绿山矿冶废弃地优势植物重金属的积累与迁移   总被引:1,自引:0,他引:1  
通过野外调查和取样分析,研究了大冶铜绿山矿冶废弃地鸭跖草等5种优势植物对重金属的吸收累积与迁移特性,以期为矿区退化生态系统的植被恢复、重金属污染土壤的治理等提供依据。结果表明,鸭跖草等5种植物对重金属Cu、Pb、Zn、Cd、Cr都有程度不等的高量积累,尤其是铜元素,其最高积累量出现在海洲香薷根部,达到844.65 mg/kg,是一般植物Cu含量(5~25 mg/kg)的33.8~1689倍;而在同样条件下,As在5种植物体内的含量为018~098 mg/kg,远远低于As在一般植物中的含量(<10 mg/kg),这说明这些植物对As可能具有某种规避机制。从植物对重金属的吸收、富集和转运能力综合考虑,鸭跖草等5种植物都不太可能是重金属Cu等6种重金属的超累积植物。但是,它们对重金属所表现出的耐性无疑对矿冶废弃地的植被恢复过程有重要意义。  相似文献   

6.
Mineral extraction activities, such as those conducted by oil, gas and coal industries, are widespread throughout the Arctic region. Waste products of these activities can result in significant contributions to the radioactive burden of the surrounding environment due to increased concentrations of naturally occurring radioactive materials (NORM) to levels that would not normally be found in the environment. Coal mining operations commenced in the early 1900s on Svalbard and have been conducted at a variety of locations on the archipelago since then. Coal contains radionuclides of the uranium and thorium series as well as 40K. Extraction and processing of coal can result in releases of these radionuclides to the broader environment with subsequent impact on the human and non-human inhabitants of the area. This paper presents the results of a study on environmental radioactivity resulting from historical coal mining operations conducted at Ny-Alesund, Spitsbergen, in the Svalbard archipelago. Activity concentrations of radionuclides found in materials associated with these operations are presented as well as the results of a spatial dosimetric survey conducted over an area affected by coal mining.  相似文献   

7.
铜陵地区矿山生态环境综合治理途径   总被引:13,自引:0,他引:13  
分析了铜陵地区矿山生态环境存在的主要问题,将其分为矿山“三废”排放与污染。矿山生态环境破坏和矿山地质灾害等三类。在此基础上,提出矿山生态环境整治必须从管理制度、经济和技术方面寻找综合治理途径。其中,管理制度方面:完善矿山生态环境保护的法规体系,实施矿山环境准入制度,确立科学合理的矿山生态环境保护目标和评价标准;经济方面:建立明晰的矿山环境资产产权制度,建立经济激励机制,建立多元化、多渠道投资机制,发展矿山生态环境保护整治产业;技术方面:开发矿业清洁生产技术,矿区土地复垦和生态重建技术,矿山水均衡破坏防治工程技术,开展矿山环境保护的科学技术研究与国际合作。  相似文献   

8.
城市矿产是工业化和城市化过程的产物,它是蕴藏于城市中有较高经济价值并可回收利用的二次资源,具有载能性、循环性、战略性。随着工业化、城镇化和消费持续升级,"垃圾围城"已然成为中国许多大中城市亟需解决的环境问题,严重阻碍中国的可持续发展。城市矿产变废为宝,能有效化解资源与环境双重约束。为此,中国政府先后出台一系列城市矿产产业政策以推动其快速发展。本文收集1987—2015年国家层面颁布的相关政策文件,在运用内容分析法对政策文本梳理、编码并统计计量的基础上,首先从颁布部门、数量、力度等方面对政策体系进行总体分析,然后构建并运用政策工具-政策作用环节两维度分析框架,探讨中国城市矿产政策体系的演化过程及发展特征。研究发现:(1)从政策发展历程分析,中国城市矿产政策体系经历了依附环境保护政策的孕育期、体系初建的形成期和效力深化的发展期。(2)从政策颁布维度分析,中国城市矿产政策颁布速度逐渐加快,力度逐渐增强,参与机构数量不断增多。(3)从政策工具维度分析,中国城市矿产政策体系以环境型政策为主,逐渐呈现出强化供给型政策的演化趋势。(4)从政策作用环节分析,中国城市矿产政策体系由重点关注回收、深加工环节向关注全产业链环节演变。最后,针对中国城市矿产政策体系演变特征与存在的不足,本文从以下三个方面提出了促进中国城市矿产产业发展的政策建议:一是加强部际联系,完善顶层设计;二是加强消费引导,完善需求型政策;三是立足产品全生命周期,健全产业政策体系。  相似文献   

9.
The release of radon gas and progeny from the mining and milling of uranium-bearing ores has long been recognised as a potential radiological health hazard. The standards for exposure to radon and progeny have decreased over time as the understanding of their health risk has improved. In recent years there has been debate on the long-term releases (10,000 years) of radon from uranium mining and milling sites, focusing on abandoned, operational and rehabilitated sites. The primary purpose has been estimates of the radiation exposure of both local and global populations. Although there has been an increasing number of radon release studies over recent years in the USA, Australia, Canada and elsewhere, a systematic evaluation of this work has yet to be published in the international literature. This paper presents a detailed compilation and analysis of Australian studies. In order to quantify radon sources, a review of data on uranium mining and milling wastes in Australia, as they influence radon releases, is presented. An extensive compilation of the available radon release data is then assembled for the various projects, including a comparison to predictions of radon behaviour where available. An analysis of cumulative radon releases is then developed and compared to the UNSCEAR approach. The implications for the various assessments of long-term releases of radon are discussed, including aspects such as the need for ongoing monitoring of rehabilitation at uranium mining and milling sites and life-cycle accounting.  相似文献   

10.
21世纪中国西部矿产资源开发的战略思考   总被引:11,自引:0,他引:11  
作为全国资源的富集区,西部矿业开发要在21世纪地区经济发展中作出应有的贡献,不仅需要一个长期的开发过程,而且更需要一个明智而有效的发展战略,从西部地区资源、环境、区位条件及长期实践出发,认真把握未来市场变化、积极推动精品为先发展,努力调整地区产品结构和合理组织空间生产应成为21世纪西部矿产资源开发战略的四项基本内容,上述战略的实施不仅有束于资源的保障、中央政府的认呆和资金与技术的支持,而且有赖于整个社会环保意识的加强。  相似文献   

11.
The trade of wastes in the world has been increasing and China has become the largest importer of wastes. This paper examines the import trend of different wastes and finds out that the total import volume to China approved by the Chinese government keeps increasing and the illegal trade can not be banned despite repeated prohibitions; therefore, China is not only "a world factory", but actually "a global garbage dump". In order to well understand the implications of wastes import, this paper further analyzes the resource and environmental effects and risks of different wastes imports as well as the strong driving force of wastes imports. Based on these detailed analysis and solid data, policy recommendations are put forward to reduce the demand for raw materials, to further strengthen the inspection of and supervision over the international trade of the wastes that can be used as raw materials by using the life cycle analysis and risk analysis, to improve the environmental standards and strengthen the disposal capacity, to re-export the raw materials produced from the imported wastes, to develop the long-term planning for the import of wastes and to promote international cooperation.  相似文献   

12.
As a significant issue, mining cities, especially the resource-exhausted mining cities have already been given intensive attention by academia and government. This article discusses the intrinsic and extrinsic reasons for problems of the mining cities from the perspective of sustainable development, quantitatively analyzes the economic benefit of the mining cities with statistical data, and presents the strategies and measures for sustainable development of the mining cities based on the theoretical discus-...  相似文献   

13.
Abstract

The trade of wastes in the world has been increasing and China has become the largest importer of wastes. This paper examines the import trend of different wastes and finds out that the total import volume to China approved by the Chinese government keeps increasing and the illegal trade can not be banned despite repeated prohibitions; therefore, China is not only “a world factory”, but actually “a global garbage dump”. In order to well understand the implications of wastes import, this paper further analyzes the resource and environmental effects and risks of different wastes imports as well as the strong driving force of wastes imports. Based on these detailed analysis and solid data, policy recommendations are put forward to reduce the demand for raw materials, to further strengthen the inspection of and supervision over the international trade of the wastes that can be used as raw materials by using the life cycle analysis and risk analysis, to improve the environmental standards and strengthen the disposal capacity, to re-export the raw materials produced from the imported wastes, to develop the long-term planning for the import of wastes and to promote international cooperation.  相似文献   

14.
Swine feedlots are widely considered as a potential hotspot for promoting the dissemination of antibiotic resistance genes (ARGs) in the environment. ARGs could enter the environment via discharge of animal wastes, thus resulting in contamination of soil, water, and food. We investigated the dissemination and diversification of 22 ARGs conferring resistance to sulfonamides, tetracyclines, chloramphenicols, and macrolides as well as the occurrence of 18 corresponding antibiotics from three swine feedlots to the receiving water, soil environments and vegetables. Most ARGs and antibiotics survived the on-farm waste treatment processes in the three swine farms. Elevated diversity of ARGs was observed in the receiving environments including river water and vegetable field soils when compared with respective controls. The variation of ARGs along the vertical soil profiles of vegetable fields indicated enrichment and migration of ARGs. Detection of various ARGs and antibiotic residues in vegetables fertilized by swine wastes could be of great concern to the general public. This research demonstrated the contribution of swine wastes to the occurrence and development of antibiotic resistance determinants in the receiving environments and potential risks to food safety and human health.  相似文献   

15.
Monitoring large (underwater) surfaces, with rapidly varying composition, requires a sampling density which exceeds the capabilities of standard techniques. These techniques involve sample collection and a number of treatments and measurements in the laboratory; both steps are laborious, tedious and costly. This paper presents an in situ method in which a detector system is trailed over the surface and measures continuously the gamma rays emitted by the natural radionuclides in the sediment. Since each sediment component has its own characteristic set of activity-concentration values (radiometric fingerprint), the composition of the sediment can be deduced quantitatively. This paper shows the application of this technique for monitoring the dispersal of dredge spoil from Rotterdam harbour, dumped in the North Sea. In addition to a qualitative picture of dredge spoil dispersal, a mass balance equation has been used to quantitatively assess the dredge spoil transport with time.  相似文献   

16.
Secondary arsenic minerals in the environment: A review   总被引:1,自引:0,他引:1  
Information on arsenic (As) speciation in solid materials is critical for many environmental studies concerned with As stability and/or mobility in natural As-impacted soils and mining or industrial sites contaminated by As. The investigation of these systems has provided evidence for a number of secondary As minerals that have often played a significant role in As mobility in the solid phase–water system. This paper presents a list of environmentally important secondary As minerals in contaminated soil and waste systems, summarizes the information about their origin, occurrence, environmental stability and thermodynamics, and proposes several important avenues for further investigation.  相似文献   

17.
Industry has become an essential part of modern society, and waste production is an inevitable outcome of the developmental activities. A material becomes waste when it is discarded without expecting to be compensated for its inherent value. These wastes may pose a potential hazard to the human health or the environment (soil, air, water) when improperly treated, stored, transported or disposed off or managed. Currently in India even though hazardous wastes, emanations and effluents are regulated, solid wastes often are disposed off indiscriminately posing health and environmental risk. In view of this, management of hazardous wastes including their disposal in environment friendly and economically viable way is very important and therefore suggestions are made for developing better strategies. Out of the various categories of the wastes, solid waste contributes a major share towards environmental degradation. The present paper outlines the nature of the wastes, waste generating industries, waste characterization, health and environmental implications of wastes management practices, steps towards planning, design and development of models for effective hazardous waste management, treatment, approaches and regulations for disposal of hazardous waste. Appraisal of the whole situation with reference to Indian scenario is attempted so that a better cost-effective strategies for waste management be evolved in future.  相似文献   

18.
Measurements of ambient radiation doses and determination of radionuclide concentrations in mining waste and soils were performed in 60 areas of former radium and uranium mining. In several places, mining waste and low-grade uranium ore left on the surface contain radioactivity above regional background. Most of the former mining sites present no enhanced radionuclide concentrations. However, in the mining facilities where the radioactive ore was chemically extracted, mill tailings contain materials with elevated levels of radioactivity, up to 200 times the levels in unaffected soils of the region. Mud from neutralization ponds used to treat acid mine waters contains also elevated radionuclide concentrations. Furthermore, depending on the type of waste, the radioelement composition varies. Environmental rehabilitation measures shall take these differences into account in order to prevent in the long term the radioactive contamination of agriculture soils and water resources, and to ensure adequate radiological protection to the public and to the environment.  相似文献   

19.
Early identification of the critical environmental issues arising from new energy technologies is needed to ensure adequate consideration of these issues in all phases of research and development. This study examines the potential hazards to aquatic ecosystems from large-scale exploitation (190,000 Mg/day) of the Chattanooga Shale Formation, an immense reserve of oil shale and uranium in Kentucky, Tennessee, and Alabama. Using existing data on regional ecology, hydrology, mining operations, and raw and spent shale chemistry, we identified two major, related environmental issues: (1) the potential for extensive adverse effects on aquatic communities through degradation of water quality and habitat; and (2) the potential conflict between the requirements for shale exploitation, and the habitat and water quality needs of threatened or endangered species. Specific hazards to aquatic ecosystems include erosion, sedimentation, acid mine drainage, raw and spent shale leachates, and surface disposal of immense quantities of solid wastes. Twelve of 19 federally designated, threatened or endangered fish and mollusks in the shale-bearing region were identified as known or recent inhabitants of the counties believed to be most favorable for the exploitation of shale. Of these, five species occur as single populations or are limited to a single river system. The potential for adverse effects on these species is greatest in the counties near the Tennessee-Alabama state line. Future research needs include physical, chemical, and toxicological characterizations of shale leachates and studies of the transport and fate of leachable contaminants. Such research can provide the guidance necessary to minimize impacts on aquatic communities resulting from extraction, retorting, and disposal of shale.  相似文献   

20.
Niobium, phosphate, coal and gold mining facilities have been selected as case studies with the aim of identifying possible sources of radiological impact during and after cessation of industrial operations. The results have shown that acid drainage, as well as chemical processing of mineral ores, constitute relevant impact indicators for present-day and future scenarios. The possible use of solid wastes abandoned at the end of the operations represents a long-term radiological concern. Therefore, it is necessary that Brazilian legislation for environmental licensing be revised taking into account the potential environmental and radiological impacts caused by these industries and establishing remedial procedures for waste storage areas in the existing sites. The indicators developed and procedures carried out can be used in screening for decisions on the adoption of regulatory requirements for practices at such types of installations.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号