Review of water pollution control in China

Water resource shortage and pollution has seriously threatened the survival and development of developing countries. Because of China’s specific economical and social circumstances, complete adoption of developed countries’ experience is unrealistic. At present, China needs to develop strategies and technologies in source water pollution control and municipal environmental remediation that embrace the country’s specific need to battle the water resource problem. Among them, efficient source water pretreatment is a critical step to ensure a safe municipal water supply. Unlike developed countries, it is not yet feasible in China to treat water supplied to the household and have it meet the standard of direct drinking; therefore, it is more appropriate to refer to it as service water. As a beneficial supplement, an additional community drinking water network and household drinking water apparatus can be considered.     

Control division of agricultural non-point source pollution at medium-sized watershed scale in Southeast China

This paper presents the study carried out for controlling agricultural non-point source pollution (NSP) in a medium-sized watershed covering 1.47 × 10⁴ km² in Southeast China using quantitative analysis coupled with geographic information system (GIS), universal soil loss equation (USLE), soil conservation service-curve number (SCS-CN), nutrient loss equations, and annualized agricultural nonpoint source model (AnnAGNPS). Based on the quantitative results derived from GIS and environmental models, five control division units were generated for NSP control in Jiulong River watershed, namely, controlling unit for soil losses, controlling unit for livestock breeding and soil losses, controlling unit for excessive fertilizer use and livestock breeding, controlling unit for soil losses and fertilizer use, and controlling unit for excessive fertilizer use and soil losses. This study proved that integrating GIS with environmental models can be adopted to efficiently evaluate major sources and contributors of NSP, and identify the critical source areas of NSP, which enables adjusting measures to local conditions by further control division units developed through such study for control and management of water quality degradation induced by NSP in the Jiulong River watershed.     

Diagnosis and recommendations for transjurisdictional water pollution management in China

Large-scale water environmental deterioration is one of the most prominent environmental issues in current China. Transjurisdictional water pollution is an important reason for water environmental deterioration of river basins, and currently there are some major defects that exist in China's management system related to transjurisdictional water pollution. With seven major river basins in China as an object of study, this paper is designed to perform a diagnosis of major problems about the transjurisdictional water pollution management in China from three aspects, i.e. institution, mechanism, and legislation. On the basis of this, it gives an overall train of thoughts on the reform of transjurisdictional water pollution management in China, and proposes specific recommendations from the aforesaid three aspects.     

Air pollution and its control in China

The rapid growth of China’s economy has led to severe air pollution characterized by acid rain, severe pollution in cities, and regional air pollution. High concentrations are found for various pollutants such as sulfur dioxides (SO₂), nitrogen oxides (NO_x), and fine particulates. Great efforts have thus been undertaken for the control of air pollution in the country. This paper discusses the development and application of appropriate technologies for reducing the major pollutants produced by coal and vehicles, and investigates air quality modeling as an important support for policy-making.     

Nanomaterials for water pollution monitoring and remediation

Water shortage and pollution are serious challenges for many countries. Nanomaterials are promising new tools for water quality management due to unique physicochemical properties, high economic benefit, high removal efficiency and environmental friendliness. Here we describe four types of nanomaterials used for water treatment: nanofiltration membranes, photocatalytic nanomaterials, adsorption nanomaterials and reducing nanomaterials. We discuss their properties, applications and mechanisms for pollutant removal. We also review nanomaterials used for water quality monitoring, notably nanomaterials used for the detection of trace pollutants and pathogens. These nanomaterials include carbon nanotubes, magnetic nanoparticles, noble metal nanomaterials and quantum dots.     

A review of atmospheric mercury emissions,pollution and control in China

Mercury, as a global pollutant, has significant impacts on the environment and human health. The current state of atmospheric mercury emissions, pollution and control in China is comprehensively reviewed in this paper. With about 500-800 t of anthropogenic mercury emissions, China contributes 25%-40% to the global mercury emissions. The dominant mercury emission sources in China are coal combustion, non-ferrous metal smelting, cement production and iron and steel production. The mercury emissions from natural sources in China are equivalent to the anthropogenic mercury emissions. The atmospheric mercury concentration in China is about 2-10 times the background level of North Hemisphere. The mercury deposition fluxes in remote areas in China are usually in the range of 10-50μg·m^-2·yr^-1. To reduce mercury emissions, legislations have been enacted for power plants, non-ferrous metal smelters and waste incinerators. Currently mercury contented in the flue gas is mainly removed through existing air pollution control devices for sulfur dioxide, nitrogen oxides, and particles. Dedicated mercury control technologies are required in the future to further mitigate the mercury emissions in China.     

Simulating the impacts of land-use changes on non-point source pollution in Lugu Lake watershed

Protection of the water quality of Lugu Lake is important because it is a unique geographic and cultural resource. Not only point source pollution but also non-point source pollution contribute to degradation of water quality. A GIS-NPS model, with long-term hydrologic impact assessment (L-THIA), was used to evaluate long-term implications of land-use change impacts on non-point source (NPS) pollution. The land-use patterns of 1995 and 2005 were analysed to determine the changes in Lugu Lake watershed. A 30-year (1974–2003) precipitation dataset was used to estimate mean annual surface runoff and NPS pollutant loads. The contributions of different land-use categories to average annual runoff and NPS pollutant production were assessed with a unit contribution index (UCI). Results show loss of agricultural land (by 44.9%), while forest, grass/pasture and residential land increased to different degrees from 1995 to 2005. At the same time, annual average NPS pollutants, TN, TP, TSS and BOD loads all decreased, while heavy metal lead increased by 6.87%. The UCI formulated in this research was a more useful method to assess land-use impact on NPS pollutants than simple investigations of the percentage land-use change. Agricultural and residential land changes had more impact on NPS pollutants and were identified as the main source types. Suggestions on regulating land uses and management proposals for protecting lake water quality in Lugu Lake watershed are made.     

Ecological risk assessment from the viewpoint of surface water pollution in Xiamen City,China

The ecological security of urban surface water is subject to significant risk due to rapid urbanization. Pollutant discharge and accumulation are among the most critical stressors endangering urban surface water and affecting the normal operation of urban aquatic ecosystem services. In this study, we assessed how pollutant accumulation stresses water purification systems, which perform important urban ecosystem services. First, we applied a water environmental capacity model to calculate thresholds of urban surface water environmental capacity under a given water quality target. Second, based on a stepwise regression method, an equation was used to describe the relationship between stressor factors (pollutant accumulation) and measurable socioeconomic indicators. Third, an ecological risk index was used as an assessment endpoint indicator to assess the negative ecological effect of pollutant accumulation. Finally, risk level was classified according to the risk quotient method. Taking Xiamen City as an example, we analyzed the contribution of different sources of pollutants and evaluated the urban ecological risk posed by two major contaminants present in the environment by measuring chemical oxygen demand (COD) and ammonium nitrogen (NH₄⁺-N). The results show that the ecological risk indexes of both COD and NH₄⁺-N are expected to decrease from 2020 to 2030; that of COD is expected to fall from medium to low, whereas that of NH₄⁺-N is expected to fall from high to medium. These findings demonstrate that the ecological risk posed to the surface water in Xiamen City can be reduced by controlling population growth, optimizing industrial structure, and promoting economic development.     

Ecological engineering for water in sustainable settlements construction

The components of a water system in a settlement should benefit the residents, environment and nature. Ecological engineering for water use in settlements is crucial for designing and constructing a sustainable community. This article discusses ecological engineering measures and technology case studies in China for systematic regulation of the multiple functions of water in a sustainable community. These methods include reusing all sources of water (rainwater, wastewater and surface water), separating water that has been used for different purposes, promoting nutrient cycling, and improving the self-purification of water by controlling pollutant loads.     

海平面上升对珠江口水位影响的分析

珠江三角洲水位变化存在着大量不确定性、不精确性,这些特性既具有模糊特征,也具有灰色特征。在分析珠江三角洲灯笼山站年平均水位的变化特征和闸坡站海平面变化趋势的基础上,利用灰关联法分析代表站灯笼山站年平均水位与流量、海平面、潮差等8个因素的关系,年平均水位与影响因素之间的灰关联度均大于0.7,说明各因子对年平均水位均产生显著影响,其中海平面变化与年平均水位的灰关联度为0.736,说明海平面变化是年平均水位的重要影响因素。选取灰关联度较大的（马＋三）流量、闸坡站海平面、灯笼山站的年最高水位、年最低水位、年平均低潮、年平均潮差这6个指标进行主成分分析。结果表明：第一主成分为径流潮汐作用,第二主成分的代表因素为海平面上升,第三主成分的代表因素为年最高水位;其中海平面上升为代表的第二主成分对年平均水位的贡献率为20.1%。因此,海平面上升对灯笼山站年平均水位的影响虽然弱于径流潮汐作用,但其影响也是显著的。     

Efficient air pollution abatement for regions in China

This paper computes the efficient air pollution abatement ratios of 30 regions in China during the period 1996–2002. Three air emissions (SO₂, soot and dust) are considered. Data envelopment analysis (DEA) with a single output (real GDP) and five inputs (labour, real capital stock, SO₂, dust and soot emissions) is used to compute the target emissions of each region for each year. The efficient abatement ratios of each region in each year are then obtained by dividing the target emission by the actual emission of an air pollutant. Our major findings are: 1. The eastern area is the most efficient region with respect to SO₂, soot and dust emissions in every year during the research period. 2. The eastern, central and western areas have the lowest, medium and highest 1996–2002 average target abatement ratios of SO₂ (22.09%, 42.23% and 57.58%), soot (26.19%, 56.34% and 66.37%) and dust (15.20%, 29.09% and 40.59%), respectively. 3. These results are consistent with the Environmental Kuznets Curve (EKC) theory, whereby a more developed area will use environmental goods more efficiently than a less developed area. 4. Compared to dust emission, the average target abatement ratios for SO₂ and soot emissions (as direct outcomes of burning coal) are relatively much higher for all three areas.     

珠江三角洲水位演变分析

全球气候变暖导致的海平面加速上升已是不争的事实,其长期累积的结果将给沿海地区造成巨大威胁。利用层次聚类分析法、灰关联法、相关分析法等重点分析了海平面上升对珠江三角洲水位的影响。结果显示：海平面上升对珠江三角洲代表站的年平均水位和年最低水位的影响大于对年最高水位的影响;海平面上升对马口站和三水站水位的影响小于河床下切和径流的影响;海平面上升对珠江河口区水位的影响由三角洲深处向口门区有增强趋势。掌握海平面上升对水位的影响规律,对于河口地区的防灾减灾和水资源的合理开发利用具有重要的指导意义。     

Calculation of the unit emergy value of water in an Italian watershed

Emergy is a thermodynamics-based entity that enables the implementation of a holistic environmental accounting system. It contributes to identify and measure all the inputs (energy and matter) supporting a given system, expressed in a common unit, namely solar emergy joule (sej). The emergy per unit product (called unit emergy value, UEV), is a measure of the environmental cost of a given resource. It is specific of the system/process and gives information on the dynamics, components and functioning of it. This paper presents the emergy evaluation of water resources within the watershed of the river Sieve, located in the Province of Florence (Italy). Along the river, an artificial basin has been created by means of a dam to preserve water quantity and quality, and to protect the Florentine area from dangerous floods and inundations. Different UEVs of water can be identified along the course of the river, especially upstream and downstream of the dam. These values quantify both the environmental and human efforts made to ensure and regulate the presence of water at different points of the river. The UEV of water flowing in the river increases from 1.35 × 10⁵ sej/g upstream, to 5.80 × 10⁵ sej/g downstream of the dam, depending mainly on man-made infrastructure. Along the watershed, three different systems of extraction, purification and distribution of water have been chosen on the basis of their dimension, type and location. UEVs of water distributed and the emergy investment necessary to implement different water management strategies are presented. The value of water purified and distributed decreases from 2.00 × 10⁶ sej/g for the smallest plant in the mountainous area, to 1.72 × 10⁶ sej/g for the largest plant, in the city of Florence, depending on production efficiency.     

中国农村环境污染防治研究综述

农村环境污染防治是农村生态环境建设的核心内容,加强农村环境污染防治研究,对解决我国独特的农村环境污染问题,具有积极的理论和现实指导意义。如何进一步探索农村环境污染防治机制的研究范式,需要在理论和方法上均有所突破。采用文献资料法和对比分析法,在简要分析了国外的研究进展基础上,重点总结了中国农村环境污染防治的研究现状,提出当前研究中存在的问题以及今后的探索方向。结果表明,近年来我国农村环境污染防治及其相应的理论与实践研究均取得较大进展,但与农村社会可持续发展的现实要求尚有不小差距。国内学者对于农村环境污染的研究主要集中在污染防治的基础理论、污染状况及质量评价、基于不同层次的农村环境污染影响因素以及污染防治机制和政策4个方面。当前的研究存在诸多不足,例如：综合防控研究的理论体系不完善,较多地关注造成农村环境污染的显性影响因子,而忽视了大量限制因子,研究中采用的数据和参照标准缺乏统一口径,空间尺度选择不一和时间尺度难以衔接等,这些都将成为今后研究亟需解决的问题。     

琼江河流域森林生态系统水源涵养能力估算

森林生态系统的水源涵养功能是其生态功能的重要组成部分.琼江流域森林生态系统是长江上游生态屏障的重要组成部分,其森林生态系统的水源涵养功能将极大地影响当地的生产生活.文章以四川省遂宁地区琼江河流域2007年森林资源二类调查数据为基础,运用综合蓄水能力法,比较了研究区不同森林类型、林龄、海拔、坡度下的林冠降雨截留能力,枯落物最大持水量和土壤蓄水能力,评估了区域尺度森林生态系统的水源涵养能力.结果表明,2007年,研究区内森林生态系统涵养水源总量为1125.02×104 m3.其中,林冠层截留占总涵养水源量的18.07%,枯枝落叶层持水量占3.34%,土壤蓄水量达到78.59%,是森林涵养水源的主体.柏木因其面积上的优势,使得其水源涵养贡献率最大,达到92.44%;阔叶混交林单位面积涵养水源量最大,达到1568.39 t·hm-2,其次是针阔混交林(1517.10 t·hm-2),经济林(1461.99 t·hm-2),针叶混交林的水源涵养能力最弱,仅1045.39 t·hm-2,主要是因为研究区内针叶混交林土壤的非毛管孔隙度较小.因绝大多数有林地的海拔都处在300~500 m处,使得其水源涵养贡献率最大,达到98.65%.同时,平坡森林生态系统的水源涵养能力最强,达到1171.92 t·hm-2,其次是缓坡,可达1150.59 t·hm-2,能力最小的是陡坡森林生态系统,仅1147.34 t·hm-2.近50 a来,研究区内森林覆盖率变化较大,按照其“十二五”规划,研究区在2015年森林覆盖率将达到45%,根据其森林面积的变化估计其森林涵养水源量可达1511.2×104 m3.在对研究区水源涵养功能及其差异认识的基础上,进行合理经营与管理,可以最大限度地发挥森林生态系统服务功能.     

Optimization models for environmental pollution control: A synthesis

The optimization models presented here represent a synthesis between input-output analysis and mathematical programming models for environmental pollution control. The pivotal construct is a social cost for each unit of consumption; it is derived from the input-output analysis and is used in the objective function of the mathematical programming models which seek to optimize the final value of bill of goods and bads. The theory of optimization with relative bounded variables in nonlinear programming is developed and utilized.     

小流域水土保持综合治理效益指标体系及其应用

在分析总结已有水土保持综合治理效益评价指标与方法的基础上,结合黄土高原沟壑区自然、经济、社会条件及治理特点,遴选了9个评价指标,并采用层次分析的方法对两个典型小流域的效益进行了评价。     

Reclamation and pollution control at a severely disturbed minesite in northern New Brunswick,Canada

This site in north-eastern New Brunswick, Canada, was developed as an open-pit copper mine in the early 1970s. The site was left in a severely disturbed state, contaminating the local drainage for over 10 years. Contamination to local runoff included low pH, high concentrations of lead, copper, zinc and iron and elevated concentrations of metals in general. Action taken to alleviate, the problems in the local drainage and establish a programme of site reclamation is described. The programme included water diversion, improvements in water quality control, site grading, material relocation and revegetation.The author was employed as site coordinator for Anaconda's health, safety and environmental activities during the period when the programme described in this paper was undertaken.     

Water environmental planning and management at the watershed scale: A case study of Lake Qilu, China

Water environmental planning and management has become essential for guiding the water pollution control activities. Past water pollution control activities have been site specific, with little thought on water quality standard reaching at the watershed scale. Based on the watershed approach, a seven-step methodological framework for water environmental planning and management was developed. The framework was applied to water environmental planning and management of the Lake Qilu watershed in Yunnan Province, China. Results show that the reduction amount of total nitrogen (TN) under the plan is 1,205 tons per year so that the target of environmental capacity can be reached in 2020. Compared with traditional methods, the framework has its prevalence and could be generalized to analogous watersheds.