丁苯橡胶废水的水质特性及其生物急性毒性分析

对典型丁苯橡胶废水进行了水质综合分析,并利用凝胶排阻色谱、傅里叶红外光谱和荧光光谱对废水中的溶解性有机物(DOM)进行了有机物特性分析。为了进一步分析DOM的组成与可生化性的关系,利用树脂将其分离为疏水酸性有机物(HoA)、疏水碱性有机物(HoB)、疏水中性有机物(HoN)以及弱憎水酸性有机物(WHoA)和亲水性有机物(HiM)五种组分,分别考察了DOM中各组分的比例分布及其生物急性毒性。结果表明:DOM是单体物质和聚合物的混合体,重均分子量约2 583Da,主要含有微生物代谢产物和可见区类富里酸荧光物质。DOM中疏水性有机物和亲水性有机物所占比例分别为40.23%和59.77%,其中HoN和HoA具有相对较高的芳香度和分子量。生物急性毒性结果表明:疏水性有机物的急性毒性显著高于亲水性物质,其中含量较低的WHoA和HoB的急性毒性最强。     

不同埋龄垃圾渗滤液中有机物在矿化垃圾床内的转化与去除

研究利用矿化垃圾床在准好氧工况下处理不同埋龄垃圾渗滤液,对渗滤液水质如COD、BOD、氨氮和总氮等几项指标进行了监测,分析了矿化垃圾床对两种渗滤液的处理效果。结果表明,矿化垃圾床对老龄和年轻垃圾渗滤液的COD处理率分别达70.21%和88.09%,但两者出水的B/C值均0.04。同时,在对三维荧光和紫外可见光谱的分析中得出,年轻垃圾渗滤液的出水中几乎不含小分子色氨酸类有机物。并且分子量分布结果表明两体系内的小分子类有机物占比均有所提高,表明了准好氧矿化垃圾床优先降解渗滤液中的大分子有机物,使得小分子有机物占比提高。因此,准好氧矿化垃圾床可应用于不同填埋龄垃圾渗滤液的前处理中,且效果良好。     

水环境中挥发性有机物的监测方法

挥发性有机物具有种类多、含量少以及毒性大等特点,已成为我国水质监测优先控制污染物。本文叙述了近年来水中挥发性有机物在环境监测中的研究现状,主要介绍了4种预处理技术和两种分析方法,同时简单介绍了水环境中挥发性有机物的发展方向。     

地表水中挥发性有机物浓度变化特征及来源建模分析

常规方法分析挥发性有机物(VOC)浓度变化特征时，仅考虑挥发速率这一因素，忽略了比增长和比去除速率的干扰，导致有机物浓度变比模拟值与实测值偏差较大，针对这一问题，提出地表水中挥发性有机物浓度变化特征及来源建模分析。应用质谱联用法，获得有机物质谱图，根据测定的水样浓度，计算有机物比增长和比去除速率，结合挥发速率建立变化特征模型，识别有机物污染来源。选取具有代表性的水源地，设置对比实验，结果表明，设计方法相比两组常规方法，生活源有机物浓度变比模拟偏差分别减小了3.09%和5.02%,农业源浓度变比模拟偏差分别减小了3.03%和5.40%,工业源浓度变比模拟偏差分别减小了3.97%和6.75%,浓度变化趋势与实测浓度最为贴近。减小了挥发性有机物浓度变化的模拟值偏差，对水域有机物浓度变化预测更为准确。     

氯离子对过一硫酸盐法处理垃圾渗滤液的研究

为探究氯离子(Cl^-)对过一硫酸盐法(PMS)去除垃圾渗滤液中氨氮和难降解有机物的影响,通过改变Cl^-浓度和氨氮浓度,采用常规水质指标分析及三维荧光光谱分析,对比了Cl^-对PMS体系处理垃圾渗滤液中活性氯的累积生成情况、氨氮的转化影响和难降解有机物的去除效果。结果表明,在无氨氮时,Cl^-可以增强垃圾渗滤液中有机物的降解效果;当初始氨氮浓度为60 mg/L,反应60 min时,垃圾渗滤液中氨氮的去除率可达90%以上,但UV₂₅₄去除率从22.96%大幅下降9.27%,说明了Cl^-的存在可以促进渗滤液中氨氮的转化但会影响芳香性有机物的去除效果。三维荧光分析结果进一步证明了Cl^-可以降低PMS体系处理后垃圾渗滤液中有机物的腐殖化程度,但氨氮的存在会削弱高含氯垃圾渗滤液中腐殖质的去除效果。本文研究结果可为优化过一硫酸盐法处理高含Cl^-垃圾渗滤液中氨氮与有机物提供理论基础。     

电气浮法去除钻井废水COD机理研究

借助有机物红外光谱分析,探讨了采用电气浮法处理前与处理后废水中有机物的结构变化情况,并对电气浮法去除钻井废水COD的机理进行了初步探析。结果表明,某些有机物如磺化沥青在采用电气浮法处理前与处理后其分子结构发生了很大变化,在一定程度上被氧化降解,其去除以电解氧化还原作用为主,电解絮凝和电解气浮作用为辅;而某些有机物主要是在电解絮凝和电解气浮作用下去除的。     

离子交换树脂的有机物污染及其复苏

综述了树脂污染和树脂吸收有机物的机理,并对污染树脂常用的几种复苏方法作了简要介绍和比较。自然界中甲基化速度加快会使水质恶化,富里酸离解产生的离子与树脂中甲基污染物反应可以去除树脂中的有机污染物。离子型树脂吸附有机物能力低于OH-型树脂,用Cl-型树脂作为有机物清除剂是因为洗脱容易,但由于吸附能力低,有机物容易漏过,对除盐不利。经过对几种复苏方法的比较,有机溶剂法是效果最好的复苏方法,复苏后,可以大大提高树脂的理化性能。     

新装修居室甲醛、总挥发性有机物浓度变化规律分析

通过对乌鲁木齐市新装修居室空气连续6个月的追踪监测,分析新装修居室甲醛、总挥发性有机物浓度的动态变化规律。结果表明,室内甲醛的浓度随装修竣工后时间的增加呈现降低趋势,但到第6个月为止,绝大部分住户室内空气甲醛浓度依然超标。总挥发性有机物的浓度降低趋势较为明显,到第5个月时,绝大部分住户室内空气总挥发性有机物浓度达到国家标准限值的要求。室内空气甲醛浓度的降低是一个长期缓慢的过程,居室内甲醛污染对人体健康的危害应引起人们的足够重视。     

GC-MS法测定垃圾填埋场渗滤液中的有机污染物

采用GC-MS联用技术对深圳市两个垃圾填埋场（A和B）渗滤液中的有机污染物进行分析。垃圾场A是简易生活垃圾填埋场，垃圾场B是生活垃圾焚烧底渣填埋场。垃圾场A渗滤液中COD、TOC、NH3-N、NO3^--N等污染指标的浓度比垃圾场B渗滤液高一个数量级。两个垃圾填埋场渗滤液中分别检测出主要有机物72种和57种，其中含有大量难降解有机物，如酚类、胺类、杂环类物质。两个垃圾填埋场渗滤液中有机物组分的相对含量不同，渗滤液A中酚类物质含量最高，渗滤液B中有机物多为长链烷烃。     

家里的灰霾——中国家庭室内灰尘中有毒有害物质抽样调查

家庭室内灰尘是考察室内污染情况的"晴雨表"。近期,针对目前国际国内关注度较高的四类有毒有害物质,绿色和平采集了中国五个城市十一个家庭的室内灰尘样本进行检测。结果显示全部样本中都存在上述四类有毒有害物质,且浓度范围与其他国家和地区的研究相一致。这表明中国公众可能通过室内灰尘暴露于多种有毒有害物质的复合影响之下。有此,绿色和平建议完善中国化学品管理体系,为公众创造一个"无毒"的未来。     

BIOLOGICAL INDICATORS AND BIOLOGICAL EFFECTS OF ESTUARINE/COASTAL POLLUTION1

ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.     

Hydrological,Physical, and Chemical Functions and Connectivity of Non‐Floodplain Wetlands to Downstream Waters: A Review

We reviewed the scientific literature on non‐floodplain wetlands (NFWs), freshwater wetlands typically located distal to riparian and floodplain systems, to determine hydrological, physical, and chemical functioning and stream and river network connectivity. We assayed the literature for source, sink, lag, and transformation functions, as well as factors affecting connectivity. We determined NFWs are important landscape components, hydrologically, physically, and chemically affecting downstream aquatic systems. NFWs are hydrologic and chemical sources for other waters, hydrologically connecting across long distances and contributing compounds such as methylated mercury and dissolved organic matter. NFWs reduced flood peaks and maintained baseflows in stream and river networks through hydrologic lag and sink functions, and sequestered or assimilated substantial nutrient inputs through chemical sink and transformative functions. Landscape‐scale connectivity of NFWs affects water and material fluxes to downstream river networks, substantially modifying the characteristics and function of downstream waters. Many factors determine the effects of NFW hydrological, physical, and chemical functions on downstream systems, and additional research quantifying these factors and impacts is warranted. We conclude NFWs are hydrologically, chemically, and physically interconnected with stream and river networks though this connectivity varies in frequency, duration, magnitude, and timing.     

Ethical Issues Related to Food Sector Evolution in Developing Countries: About Sustainability and Equity

After a century of major technicaladvance, essentially achieved by and for theindustrialized countries, the evolution of thefood sector in southern countries should nolonger be thought of in terms of a ``headlongpursuit.'' In the present context of demographicgrowth, urbanization, poverty and disparities,environmental degradation, and globalization oftrade, new priorities have emerged, and newethical questions have been raised, mainlyrelated to sustainability and equity. Thispaper analyses these ethical concerns in thefollowing terms: can the model of food sectordevelopment initiated by the industrializedcountries be applied to the entire world on asustainable and equitable basis, given theeffects of this development with regard to theenergy consumed, the changes in dietarybehavior and related nutritional problems, thenew demands in terms of food safety, thequestions of biodiversity, ownership ofknowledge, cultural identities, gender issues,and Man's relationship to food and Nature?     

Women and natural resource management: Illustrations from India and Nepal

This article attempts to delineate women's roles in natural resource management by highlighting their roles in management of water, agriculture, livestock, forestry and fishery. The article is based on the findings of case studies in rural areas of India and Nepal done during 2003 and 2004 by the author as well as by other researchers. Taking women as primary respondents, empirical work used participatory techniques, such as in‐depth surveys, focus group discussions and participant observation. Findings suggest that women clearly outdo men in terms of their involvement in use and management of all the studied sectors, i.e., water, agriculture, livestock, forestry and fishery. Yet, they face categorical exclusion and denial of equal sharing of benefits from natural resources. In order to ensure sustainable use of these resources, the article recommends that policy makers, planners and development workers must have a better understanding of the relative and often shifting roles of men and women in natural resource management, including division of labour, access to resources, decision‐making and traditional knowledge and practices. The article concludes with sector‐specific recommendations.     

A CONCEPTUAL FRAMEWORK FOR EVALUATING AGRICULTURAL WATER CONSERVATION POTENTIALS1

ABSTRACT: This paper defines types of water losses in irrigated agriculture and outlines potentials for water conservation. Recoverable water “losses” (seepage, leakage, and spillage during storage and conveyance, and surface runoff and deep percolation during irrigation) and irrecoverable losses (evaporation from water and soil surfaces and transpiration from plants) are described and illustrated. Some conservation terms are defined, particularly the distinction between on-farm irrigation efficiency and areawide efficiency. Briefly reviewed are agricultural water conservation technologies and their applicability. The biggest untapped potential for water conservation may be a reduction in irrecoverable losses, especially evapotranspiration. The advantages and disadvantages of reducing recoverable and irrecoverable water losses are described, including possible effects on ground water, energy, salinity, crops, wildlife, and in-stream uses. Such information may be useful in several policy and management issues, e.g., ground water overdraft and possible constraints on crops and sites to be irrigated.     

Control of Tamarix in the Western United States: Implications for Water Salvage, Wildlife Use, and Riparian Restoration

Non-native shrub species in the genus Tamarix (saltcedar, tamarisk) have colonized hundreds of thousands of hectares of floodplains, reservoir margins, and other wetlands in western North America. Many resource managers seek to reduce saltcedar abundance and control its spread to increase the flow of water in streams that might otherwise be lost to evapotranspiration, to restore native riparian (streamside) vegetation, and to improve wildlife habitat. However, increased water yield might not always occur and has been substantially lower than expected in water salvage experiments, the potential for successful revegetation is variable, and not all wildlife taxa clearly prefer native plant habitats over saltcedar. As a result, there is considerable debate surrounding saltcedar control efforts. We review the literature on saltcedar control, water use, wildlife use, and riparian restoration to provide resource managers, researchers, and policy-makers with a balanced summary of the state of the science. To best ensure that the desired outcomes of removal programs are met, scientists and resource managers should use existing information and methodologies to carefully select and prioritize sites for removal, apply the most appropriate and cost-effective control methods, and then rigorously monitor control efficacy, revegetation success, water yield changes, and wildlife use.     

ECOSYSTEM MANAGEMENT AND THE CONSERVATION OF AQUATIC BIODWERSITY AND ECOLOGICAL INTEGRITY1

ABSTRACT: Ecologically effective ecosystem management will require the development of a robust logic, rationale, and framework for addressing the inherent limitations of scientific understanding. It must incorporate a strategy for avoiding irreversible or large-scale environmental mistakes that arise from social and political forces that tend to promote fragmented, uncritical, short-sighted, inflexible, and overly optimistic assessments of resource status, management capabilities, and the consequences of decisions and policies. Aquatic resources are vulnerable to the effects of human activities catchment-wide, and many of the landscape changes humans routinely induce cause irreversible damage (e.g., some species introductions, extinctions of ecotypes and species) or give rise to cumulative, long-term, large-scale biological and cultural consequences (e.g., accelerated erosion and sedimentation, deforestation, toxic contamination of sediments). In aquatic ecosystems, biotic impoverishment and environmental disruption caused by past management and natural events profoundly constrain the ability of future management to maintain biodiversity and restore historical ecosystem functions and values. To provide for rational, adaptive progress in ecosystem management and to reduce the risk of irreversible and unanticipated consequences, managers and scientists must identify catchments and aquatic networks where ecological integrity has been least damaged by prior management, and jointly develop means to ensure their protection as reservoirs of natural biodiversity, keystones for regional restoration, management models, monitoring benchmarks, and resources for ecological research.     

Use of off-road vehicles and mitigation of effects in Alaska permafrost environments: A review

Use of off-road vehicles (ORVs) in permafrost-affected terrain of Alaska has increased sharply over the past two decades. Until the early 1960s, most ORV use was by industry or government, which employed heavy vehicles such as industrial tractors and tracked carriers. Smaller, commercial ORVs became available in the 1960s, with the variety and number in use rapidly increasing. Wheeled and tracked ORVs, many used exclusively for recreation or subsistence harvesting by individuals, are now ubiquitous in Alaska. This increased use has led to concern over the cumulative effects of such vehicles on vegetation, soils, and environmental variables including off-site values. Factors affecting impact and subsequent restoration include specific environmental setting; vegetation; presence and ice content of permafrost; microtopography; vehicle design, weight, and ground pressure; traffic frequency; season of traffic; and individual operator practices. Approaches for mitigating adverse effects of ORVs include regulation and zoning, terrain analysis and sensitivity mapping, route selection, surface protection, and operator training. We regret the untimely death of Gunars Abele on August 27, 1989; he was a valued colleague and good friend.     

Study of the saltwater pond at Capoterra,southern Sardinia: General characteristics

Capoterra Pond in southern Sardinia is described and analyzed with respect to its morphological, meteorological, physical and chemical characteristics, and its zoobenthic, zooplankton, and phytoplankton biocenoses. The birdlife, flora, and riparian associations of vegetation are studied in order to draw international attention to the importance of this lagoon, the precariousness of its ecosystem, the seriousness of current attempts to destabilize it, and the need to encourage the Sardinian authorities to initiate conservation measures, especially as rare birds have found their niches there.     

Regulation for environmental protection: The Nanticoke industrial complex,Ontario, Canada

This assessment of the environmental protection regulatory system for the $2.2 billion iron and steel plant, oil refinery, and thermal generating station composing the core of the greenfield Nanticoke industrial complex is based upon: the use of governmental and industrial research in project management; technology and institutional arrangements for environmental protection; evidence of environmental changes to date; analysis of government and industrial approval files; and interviews with government, industry, and interest group representatives. Planning, regulation, and management have been reasonably efficient and effective to the beginning of the operational stage for all three major industries as of spring 1980. Of major future concern, however, is management of the cumulative and synergistic impacts of the industries and associated development on air quality as well as the lands, waters, and sensitive ecosystems of the nearby Lake Erie coast. Continuous monitoring, more comprehensive research, and better overall coordination of government, industrial, and public interests are required if Nanticoke benefits are to be achieved without undue cost to pre-project resource users within and outside the Haldimand-Norfolk region.