土壤污染的健康危害与修复技术

土壤污染是当今社会面临的重要环境问题之一,已经对人体健康构成了严重威胁。本文将土壤污染物分为有机污染物、无机污染物、生物污染物和放射性污染物,并阐述了各类污染物对人体健康的危害,介绍了具有广阔应用前景的污染土壤修复技术,即植物修复技术和微生物修复技术。最后,本文还对解决土壤污染问题提出了具体的建议。     

基于边际成本的地方环境保护税税率制定研究

我国自2018年1月1日起开征环境保护税,《中华人民共和国环境保护税法》授予地方政府适用税额和应税污染物项目数的调整权限。为推动地方环境保护税政策制定和出台,本文在对工业企业生产运营、污染物排放、污染治理设施运行数据调查分析的基础上,构建了一套"边际治理成本+调整系数"的地方环境保护税税政制定方法,用该方法计算了某地区水污染物环境保护税适用税额,并对环境保护税应税污染物项目数增加的必要性展开了探讨。计算结果显示,该地区工业企业水污染物边际治理成本为2.36元/污染当量,可制定水污染物环境保护税额为2.8元/污染当量,应税污染物项目数按照一类水污染物前五项、二类水污染物前三项征收为宜。     

什么是污染物排放标准

污染物排放标准是指为了实现环境质量标准目标 ,结合技术、经济条件和环境特点 ,对排入环境的污染物或有害因素的控制所做的规定。污染物排放标准分国家标准和地方标准两级。国家污染物排放标准由国务院环境保护行政主管部门根据国家环境质量标准和国家经济技术条件制定 ,适用于全国范围。省、自治区、直辖市人民政府对国家污染物排放标准中未作规定的项目 ,可以制定地方污染物排放标准 ;对国家污染物排放标准中已作规定的项目 ,可以制定严于国家污染物排放标准的地方污染物排放标准。地方污染物排放标准须报国务院环境保护行政主管部门备案…     

什么是污染物排放标准

污染物排放标准是指为了实现环境质量标准目标 ,结合技术、经济条件和环境特点 ,对排入环境的污染物或有害因素的控制所做的规定。污染物排放标准分国家标准和地方标准两级。国家污染物排放标准由国务院环境保护行政主管部门根据国家环境质量标准和国家经济技术条件制定 ,适用于全国范围。省、自治区、直辖市人民政府对国家污染物排放标准中未作规定的项目 ,可以制定地方污染物排放标准 ;对国家污染物排放标准中已作规定的项目 ,可以制定严于国家污染物排放标准的地方污染物排放标准。地方污染物排放标准须报国务院环境保护行政主管部门备案…     

陶瓷工业污染物排放标准

本标准规定了陶瓷工业企业的水和大气污染物排放限值、监测和监控要求。本标准适用于陶瓷工业企业的水污染物和大气污染物排放管理，以及对陶瓷工业企业建设项目的环境影响评价、环境保护设施设计、竣工环境保护验收及其投产后的水污染物和大气污染物排放管理。本标准不适用于陶瓷原辅材料的开采及初加工过程的水污染物和大气污染物排放管理。     

石油类在河流中自净能力的研究

根据河流的特点,利用示踪剂对河流中石油类污染物的衰减情况进行了分析,建立了污染物扩散模式,确定了河流不同断面的石油通量,求出了石油类污染物的衰减系数。为污染物的排放量和河流环境容量的确定提供了保证。     

最新环境保护标准

镁、钛工业污染物排放标准 本标准规定了镁、钛工业企业生产过程中水污染物和大气污染物排放限值、监测和监控要求。本标准适用于镁、钛工业企业的水污染物和大气污染物排放管理，以及镁、钛工业企业建设项目的环境影响评价、环境保护设施设计、竣工环境保护验收及其投产后的水污染物和大气污染物排放管理。本标准不适用于镁、     

水体有机污染物的生态效应及其化学监测技术现状与展望

通过对水体有机污染定义、来源及有机污染物主要类型的介绍和说明,分析了有机污染物的生态效应——水体污染、生物富集及其毒理效应,综述了水体有机污染物的化学监测技术尤其是有机分析前处理技术的现状,并对有机污染物的研究和监测技术作出肯定,同时展望了水体有机污染物监测技术的研究趋向。     

地下水中石油类污染物运移模拟研究＊

针对我国北方某油田的地下水特点,通过室内土柱模拟实验与数值模型模拟研究了石油类污染物随地下水运移的状况。模拟结果表明,地下水石油类污染物浓度随时间变化曲线总体上呈S型;污染前期地下水中污染物浓度增加较快,随着浓度的不断累积,后期浓度增加缓慢。计算结果显示,在50m处石油类污染物首次超过浓度限值的时间为586d,1000m处石油类污染物首次超过浓度限值的时间为12590d,污染过程表现出一定的滞后性。可见,吸附作用对石油类污染物迁移的影响很大,阻滞和延迟了污染物的迁移。     

农业生态环境污染监测技术探讨

农业生态环境污染监测是以农产品污染监测为中心的各环境要素的污染监测。依据农业区域中污染源排放危害农产品的特征污染物选择大气环境污染物、水环境污染物、土壤环境污染物、农产品污染物作为监测指标;依据农业区域中各类污染源的特点布设大气环境污染、水环境污染、土壤环境污染、农产品污染监测点位;在农产品生长期或生产期,大气环境污染及水环境污染同步监测一次,农产品污染在收获时监测一次,依据污染源污染物排放强度确定土壤环境污染监测频次。     

An investigation of the relationship between raw coal characteristics and effluent quality of Kedla and Rajrappa Washeries, Jharkhand, India

An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples-raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal-Na, K, Ca, Mg, and minor elements in coal-Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing.     

Response of a stream in disequilibrium to timber harvest

Timber was harvested on South Fork of Thomas Creek, White Mountains of Arizona, USA, for the first time in 1978–1979. This caused significant increases in annual flow volumes and annual instantaneous peak flows. North Fork remained untouched, but both streams were in disequilibrium before harvest time. Due to wetter years during the postharvest period, North Fork also experienced some flow increases, but the difference was not significant. Flow increases cause increased erosion in disequilibrium channels. While in South Fork channel cross sections enlarged by 10% since preharvest time, those in North Fork enlarged by only 2.5%. The number of knickpoints tripled in South Fork, which was about double that in North Fork. Knickpoint development resulted in destruction of the natural control structures (log steps and transverse gravel bars) in South Fork (47%), while in North Fork they increased by 23%. Knickpoints are scarps on the channel bed that have the appearance of gully headcuts. The tripling of the number of knickpoints signifies that adjustment processes of the bed profile are intensified drastically in South Fork. The geomorphic changes signify that due to increases in discharge, the extent of disequilibrium is exacerbated in South Fork. Yet, volumes of erosion are relatively small, as will be sediment volumes leaving the watershed at a given time, because of the stepwise sediment transport occurring in this ephemeral stream.     

Soil,water and plants contamination by total chrome and chrome VI

The chrome (Cr) is a metal utilized in various industrial sectors and its investigation in the environment is necessary, for the Cr (III) contain aessential micronutrients in the human nourishment and the Cr (VI), on the other hand, is toxic. In the present work soil contamination with Cr was realized in drainagelysimetersset in concentrations of 0, 200, 400, 600, 800 and 1000 mg kg⁻¹ of total Cr, with the intuition to determine the total Cr and Cr (VI) flux in leached water, in soil and in plants of lettuce (Lactuca sativa L.). In the lysimeters were cultivated four plants, in three cultivation circles. In the end of the cultivations was observed, that the total applied Cr leached in the soil, evidencing the Cr mobility in latossoil with simulant characteristics to the ones utilized in this paper. The Cr (VI) concentrations in the soil increased soon after the treatment applications, but tend to decrees in the time elapse, the same tendences were observed for the total Cr concentrations in the leached water. The Cr absorption by plants was related to the Cr disponibility in the soil, for the soil concentration and the plants decreased with time passing. The Cr mobility in the soil possibilitated the groundwater contamination presenting risks to the water quality and, consequently to public health.     

IDENTIFICATION OF CHANGES IN STREAMFLOW CHARACTERISTICS1

ABSTRACT: A set of procedures for identifying changes in selected streamflow characteristics at sites having long‐term continuous streamflow records is illustrated by using streamflow data from the Waccamaw River at Freeland, North Carolina for the 55‐year period of 1940–1994. Data were evaluated and compared to streamflow in the adjacent Lumber River Basin to determine if changes in streamflow characteristics in the Waccamaw River were localized and possibly the result of some human activity, or consistent with regional variations. Following 1963, droughts in the Waccamaw Basin seem to have been less severe than in the Lumber Basin, and the annual one‐, seven‐, and 30‐day low flows exhibited a slightly increasing trend in the Waccamaw River. Mean daily flows in the Waccamaw River at the 90 percent exceedance level (low flows) during 1985–194, a relatively dry period, were very nearly equal to flows at the same exceedance level for 1970–1979, which represents the 10‐year period between 1940 and 1994 with the highest flows. Prior to the 1980s, flows per unit drainage area in the Waccamaw Basin were generally less than those in the Lumber Basin, but after 1980, the opposite was true. The ratio of base flow to runoff in the Waccamaw River may have changed relative to that in the Lumber River in the late 1970s. There was greater variability in Waccamaw River streamflow than in Lumber River flow, and flow variability in the Waccamaw River may have increased slightly during 1985–1994.     

Assessing the US Clean Water Act 303(d) listing process for determining impairment of a waterbody

This study evaluated the US Clean Water Act (CWA) Section 303(d) listing and delisting processes, based on historical and current federal and state guidelines, to determine whether there are regional differences in water quality assessment criteria used by various states to determine impairment of a waterbody for inclusion in the 303(d) list. A review of almost 50 total maximum daily load (TMDL) and delisting documents revealed that the basis for listing or delisting a waterbody varies considerably and that, in many cases, determination of impairment was based on insufficient water quality information. Historical USEPA guidance on the 303(d) listing and delisting processes has been generally broad, resulting in wide interpretation of the assessment criteria by various states. This has led to unclear or conflicting listing methodologies among states, leading to inconsistencies in impairment determination. Common problems include inconsistent data quality and quantity, differences in frequency of monitoring, variable interpretation of narrative water quality standards, and differences in specificity of implementation and monitoring plans, resulting in significant difference in the basis for listing and delisting waterbodies. In response, several states have taken the initiative to provide much more specific guidance for their internal agencies. Listing and delisting criteria are generally clearer at the state level, but the development of differing state guidance documents has resulted in diversity in the development of the 303(d) lists and in the process of delisting a waterbody. While state guidelines are better able to address local considerations, such as variations in climate, landuse, and water quality objectives, as well as social and economic preferences, the variation in listing criteria has led to inconsistencies across state boundaries in the levels of attainment of national water quality objectives. For stakeholders that participate in the 303(d) listing process within a particular state, these types of discrepancies may not have a significant impact. However, these inconsistencies can lead to confusion for some stakeholders who participate in the process in multiples states, and must deal with differing and sometimes conflicting requirements depending on the location of their facilities.     

土壤微塑料污染及其分析方法

微塑料作为环境介质中的新型污染物,其对生态系统的影响越来越受到关注。土壤是环境中微塑料的重要蓄积库,结合近些年来国内外关于土壤中微塑料的研究,针对土壤中微塑料的来源、生态效应、分析方法及污染防治进行综述,以便更全面的了解土壤中微塑料污染的现状及其潜在的生态环境风险。塑料包装废弃物、农用地膜破碎、大气沉降是土壤中微塑料的主要来源。微塑料可吸附土壤中的重金属和有机物,作为其他污染物的载体危害生态环境健康,并会随着食物链逐渐富集,从而影响人类健康。土壤中的微塑料可通过筛分干燥后采用密度分离法、加压流体萃取法、石油提取法等进行分离,并通过消解去除土壤中的有机质。土壤中微塑料的识别与表征可采用目检法、红外光谱法、拉曼光谱法、扫描电镜法等。此外,根据土壤微塑料的生态效应提出污染治理措施与未来研究方向展望。     

Effects of Impervious Area and BMP Implementation and Design on Storm Runoff and Water Quality in Eight Small Watersheds

The effects of increases in effective impervious area (EIA) and the implementation of water quality protection designed detention pond best management practices (BMPs) on storm runoff and stormwater quality were assessed in Gwinnett County, Georgia, for the period 2001‐2008. Trends among eight small watersheds were compared, using a time trend study design. Significant trends were detected in three storm hydrologic metrics and in five water quality constituents that were adjusted for variability in storm characteristics and climate. Trends in EIA ranged from 0.10 to 1.35, and changes in EIA treated by BMPs ranged from 0.19 to 1.32; both expressed in units of percentage of drainage area per year. Trend relations indicated that for every 1% increase in watershed EIA, about 2.6, 1.1, and 1.5% increases in EIA treated by BMPs would be required to counteract the effects of EIA added to the watersheds on peak streamflow, stormwater yield, and storm streamflow runoff, respectively. Relations between trends in EIA, BMP implementation, and water quality were counterintuitive. This may be the result of (1) changes in constituent inputs in the watersheds, especially downstream of areas treated by BMPs; (2) BMPs may have increased the duration of stormflow that results in downstream channel erosion; and/or (3) spurious relationships between increases in EIA, BMP implementation, and constituent inputs with development rates.     

HERBICIDE AND NITRATE VARIATION IN ALLUVIUM UNDERLYING A CORN FIELD AT A SITE IN IOWA COUNTY,IOWA1

ABSTRACT: A hydrologic investigation to determine vertical and seasonal variation of atrazine, alachlor, cyanazine, and nitrate at one location and to relate the variation to ground-water movement in the Iowa River alluvium was conducted in Iowa County, Iowa, from March 1986 to December 1987. Water samples were collected at discrete intervals through the alluvial sequence from the soil zone to the base of the aquifer. Alachlor, atrazine, and cyanazine were detected most frequently in the soil zone but also were present in the upper part of the alluvial aquifer. Alachlor was detected sporadically, whereas, atrazine, cyanazine, and nitrate were present throughout the year. In the alluvial aquifer, the herbicides generally were not detected during 1986 and were present in detectable concentrations for only a short period of time in the upper 1.6 meters of the aquifer during 1987. Nitrate was present throughout the alluvium and was stratified in the alluvial aquifer. The largest nitrate concentrations were detected in the middle part of the aquifer. Nitrate concentrations were variable only in the upper 2 meters of the aquifer. Vertical movement of herbicides and nitrate in the soil correlated with precipitation and degree of saturation. A clay layer retarded vertical movement of atrazine but not nitrate from the soil layer to the aquifer. Vertical movement could not account for the chemical variation in the alluvial aquifer.     

FISH EMBRYOS: PRACTICAL INDICATORS OF ENVIRONMENTAL QUALITY OF SIGNWICANCE TO FISHERIES1

ABSTRACT: Cyto-embryological analyses of fish eggs collected in nature can be a more sensitive indicator of environmental pollution than more typical assays conducted on artificially-spawned eggs. This is because uncertainties associated with artificial spawning and rearing are dispensed with, as well as because of the sensitivity of some cellular and subcellular analyses. At the same time, such measures can provide information on interannual differences in egg viability of importance in elucidating great, unexplained variability in fisheries recruitment. Extensive experience with fish embryos from ocean plankton has led to the choice of a particularly useful, practical suite of observations for different developmental stages. This includes measures of embryo mortality, mutagenicity, teratogenicity, abnormal cell differentiation, and development rate. Atlantic mackerel egg mortality has been determined to be greater in the surface waters of the New York Bight apex and along the New Jersey coast than in less polluted portions of the Bight. Chromosome abnormality of mid-stage embryos was also greater in more impacted areas of the same water mass, as well as in the somatic cells of adult mackerel and winter flounder, and in juvenile and adult windowpane flounder caught in more impacted areas. Mortality and abnormality of the mackerel embryos showed statistical associations with toxic hydrocarbons as measured in plankton, and with heavy metals as measured in sea surface waters. The sensitivity, practicality, and relevance of the cytoembryological studies to population dynamics of resource species make this an important means of monitoring environmental quality.