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1.
为了老城区河道的合理整治,采用总有机碳(TOC)分析仪对常州市老城区3条河流及区域内浅层地下水的14个采样点水样进行3个月的总有机碳含量检测。老城区水环境受到不同程度的有机污染,某些地下水的TOC含量高于地表水,原因为地表水补给地下水,且老城区水体污染源主要来源于周边地区的生活污水,并受到关河、雨水等的影响,这为常州市老城区水污染治理提供了依据。  相似文献   

2.
对银川地区菜地土壤和蔬菜中有害元素进行调查并作出初步评价.表明该地区菜田土壤中氟、铅、汞有一定程度污染,镉污染也已露头;一定比例的蔬菜中,受到轻污染的元素有:铜、锌、铅、镉、砷和氟;汞在28.3%~53.2%的大白菜和青萝卜中受到中度及重度污染.  相似文献   

3.
石油资源开发中的环境污染问题   总被引:1,自引:0,他引:1  
本文叙述了石油资源开发中“三废”对大气、地表水、地下水、海洋、土壤等造成的污染问题。  相似文献   

4.
铬渣对中国地下水、地表水和土壤造成了严重污染,并对生态环境和人体健康构成了巨大威胁。开展对铬渣污染场地的修复工作已迫在眉睫。在分析铬污染特性的基础上,阐述了国内外最新铬污染场地修复技术研究动态,并概括分析了其不足与未来铬渣污染场地修复技术的发展趋势。  相似文献   

5.
畜禽养殖场污染状况监测与评价   总被引:1,自引:0,他引:1  
对河南省三个有代表性的规模化养殖场污染物排放及其对周围环境的影响进行了调查、监测及评价,结果表明,畜禽养殖污染已成为农业面源污染的重要来源,对其周围地表水和地下水产生较大影响。  相似文献   

6.
以成都平原某废弃铅蓄电池污染场地为例,调查识别典型工业场地主要污染物空间分布特征和剖面迁移特征。结果表明:场地主要潜在Pb污染源有建筑垃圾、土壤及残留废水,潜在污染途径为大气降尘、含Pb废水排放;建筑垃圾中Pb、Cd、As等污染严重;场地内酸液暂存池和清洗池地表水中Pb、Cd超标严重,均为劣Ⅴ类;场地内及周边环境地下水中Cd、Cr污染较重;区内表层土壤中Pb、Cd污染严重,且呈面源性,距循环水池及酸液暂存池1.2 m处土壤中Pb含量远高于周边区域。  相似文献   

7.
以沧州地区的地下水、土壤和小麦中的氟元素为研究对象,探讨氟元素在地下水、土壤和小麦等不同介质中的含量、空间分布与来源成因。通过绘制各介质中氟元素分布图,获得氟元素在各介质中不同深度的含量及水平空间上的分布特征。结果显示,当地深层地下水氟含量平均为2.25 mg/L,高于浅层地下水的平均值0.80 mg/L;深层和浅层土壤氟含量接近,平均值分别为557.18、569.20 mg/kg;小麦中的氟含量最高值为0.96 mg/kg,当地小麦氟含量均低于国家标准限值(1.0 mg/kg)。根据氟元素的分布特点分析,当地深层地下水与土壤的氟元素来源一致,而不同于浅层地下水中的氟;小麦的氟元素分布受浅层土壤氟影响较大。  相似文献   

8.
张掖市某污灌区土壤环境质量调查   总被引:1,自引:0,他引:1  
对张掖市某污灌区土壤环境质量进行了调查,结果表明,灌区土壤受到一定程度的污染,为轻度污染水平,污染因子与污灌水特征因子关系密切.  相似文献   

9.
地下水资源不但存在着污染的途径与受污染的危害,同时它还与生态环境息息相关,影响着方方面面。在地下水补给地表水方面,促使了河流和湖泊的形成与发展,引起土壤的沼泽化、盐渍化、土地沙化和进一步发展的沙漠化与气候干化,影响了植被的生长以及区域性的地面沉降等诸多方面。 1.地下水与河流的关系 河流的特征可由它的补给水源来确定。河流的补给源主要可以分为三种类型:①以冰雪融水为补给源的;②以雨水和  相似文献   

10.
钼矿区周边农田土壤中重金属污染状况的分析与评价   总被引:4,自引:1,他引:3  
对钼矿区周边农田土壤重金属污染情况进行了详细研究.选择该矿区受污染农田土壤样本80个,采用HNO3-HF-HClO4混酸对土壤样品进行处理,运用欧共体参比司推荐的BCR三步连续提取法进行化学形态分析;使用等离子体发射光谱仪(ICP-AES)测定土壤样品中Mo、Pb、As、Hg、Cr、Cd、Zn、Cu、Ni的全量及各种化学形态的含量并进行评价,同时对矿区地下水进行分析;采用spas软件进行数据分析.结果表明,矿山周边农田土壤重金属主要污染物为Cd、Hg并伴有Cr污染;Nemerow综合指数6.81,综合评价结果为该区土壤已受严重污染;Cd与As污染来源基本相同,Cu、Ni、Zn污染来源基本相同,Hg有独立的污染来源;重金属中化学形态分布为残余态>有机结合态>氧化结合态>酸可提取态;重金属Cr及Hg的有效态比例较大,可能会影响农作物的正常生长;矿山周边农田土壤重金属污染的原因可能是污染地下水的浇灌,矿石的开采、运输和大气降尘等过程;有机农药及塑料农用制品的施用过程,自然成土、矿物的伴生及其转化等过程.  相似文献   

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This study performs a field analysis of the diffusion collection rate coefficients of radial geometry passive samplers to measure NO2 in a Mediterranean coastal area. The study shows that the collection rate coefficients are not constant and depend on certain environmental parameters as well as on the levels of some co-pollutants. A mathematical model, which explains the variation of the collection rate coefficient, has been established.  相似文献   

13.
The Bode catchment (Germany) shows strong land use gradients from forested parts of the National Park (23 % of total land cover) to agricultural (70 %) and urbanised areas (7 %). It is part of the Terrestrial Environmental Observatories of the German Helmholtz association. We performed a biogeochemical analysis of the entire river network. Surface water was sampled at 21 headwaters and at ten downstream sites, before (in early spring) and during the growing season (in late summer). Many parameters showed lower concentrations in headwaters than in downstream reaches, among them nutrients (ammonium, nitrate and phosphorus), dissolved copper and seston dry mass. Nitrate and phosphorus concentrations were positively related to the proportion of agricultural area within the catchment. Punctual anthropogenic loads affected some parameters such as chloride and arsenic. Chlorophyll a concentration and total phosphorus in surface waters were positively related. The concentration of dissolved organic carbon (DOC) was higher in summer than in spring, whereas the molecular size of DOC was lower in summer. The specific UV absorption at 254 nm, indicating the content of humic substances, was higher in headwaters than in downstream reaches and was positively related to the proportion of forest within the catchment. CO2 oversaturation of the water was higher downstream compared with headwaters and was higher in summer than in spring. It was correlated negatively with oxygen saturation and positively with DOC concentration but negatively with DOC quality (molecular size and humic content). A principle component analysis clearly separated the effects of site (44 %) and season (15 %), demonstrating the strong effect of land use on biogeochemical parameters.  相似文献   

14.
The composition of airborne particulate matter sampled by a conventional TEOM®, an experimental modified TEOM, operated at a lower temperature but fitted with a drier to remove moisture and a Partisol®, installed at a kerbside site in the North East of England, has been investigated. The results indicate that there is a seasonal variation in the composition of PM10 as sampled by the three monitors, with chloride concentration being significantly higher in the winter. The Partisol was found to sample a higher mass of chloride and nitrate, however the differences between the monitors was only significant for chloride. Both TEOM's were found to sample a greater mass of sulphate, although the variability in the data collected meant that significance of the results was not proven statistically. The range of artifacts associated with PM10 monitors is reviewed. Difficulties in the interpretation of results due to the variable nature of airborne particulate matter and the ability of filter based systems to accurately represent the composition of atmospheric particles are considered.  相似文献   

15.
We evaluate a field method for determining species richness andcanopy cover of vascular plants for the Forest Health MonitoringProgram (FHM), an ecological survey of U.S. forests. Measurementsare taken within 12 1-m2 quadrats on 1/15 ha plots in FHM.Species richness and cover are determined for four height classes(strata) within each quadrat and aggregated by stratum over the entireplot. We estimated (1) the agreement between experienced trainers andinexperienced technicians who collected the data on this survey(accuracy) and (2) the agreement among the technicians (precision) forresults on species richness and cover from 3 test plots at 3 timeintervals. The methods appear to be highly precise, although somediscrepancies with the values obtained by the trainers were found.Trainers found significantly more species in the ground stratum (0–0.6 m) and measured significantly more cover in the uppermost stratum(>4.9 m). The proportion of variation due to measurement error andtemporal variability was less than 13% for species richness (all strata)and cover (all but one stratum). This indicates that the method issuitable for monitoring changes in species richness and canopy coverfor a large-scale synoptic monitoring project such as FHM.  相似文献   

16.
It is proposed that the common measures of benthic community condition can be augmented with a vertical EH profile taken through the benthic bioturbation zone. Sediment EH, an electrochemical measure of oxidized and reduced compounds in sediment porewater, measures the integrative consequences of all metabolic and transport processes of the benthic community. Biota, especially microbiota, metabolize carbon using a variety of electron acceptors, including O2, SO4 and some nitrogen and metal compounds. Motile benthic macrofauna ingest and transport particles, ventilate deep burrows and anoxic sediment with overlying seawater while sedentary suspension-feeding fauna deposit suspended organic matter onto the sediment surface. Collectively, these metabolic and behavioral processes advect particles and seawater between bottom water and deep sediment and define the overall structure of porewater chemistry. That structure creates a full spectrum of biogeochemical conditions of solubility, reactivity, and microbial metabolism which remineralizes excess organic carbon and most organic contaminants, defines solubility of trace metals, and pushes the vertical EH profile toward oxidizing conditions. It is proposed that a standard EH probe inserted downward through the bioturbation zone will provide a general measure of this resulting porewater chemistry and thus the impact of feeding, irrigation, and metabolism of the total macro, meio, and microbenthic community. If such a measure can be validated it will permit extended measurement of community function and reduced efforts in measuring community structure.  相似文献   

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The National Inventory of Landscapes in Sweden (NILS) is a large-scale, sample-based monitoring program that combines aerial photointerpretation with field inventory to follow landscape-scale biophysical conditions and changes. A statistical power analysis was conducted before the NILS program began in 2003 with the aim to determine an appropriate sampling effort and compare some design alternatives. The chosen sampling effort was then evaluated in a second power analysis conducted just before the first 5-year re-inventory rotation started. The latter power analysis revealed which magnitude of actual change might be detected within the future for different central monitoring variables. This article reports results from these power analyses and discusses our experiences in using power analysis as a tool for designing large-scale monitoring programs. The results showed that even quite small changes in the more common variables, such as land cover types and more common plant species, can be detected on the national scale. However, on the regional scale, or for less common variables, changes will be more difficult to detect. The power analyses have revealed the size level of changes that will be possible to detect. The results have also generated incentives for further improvements of NILS, e.g., input to the modification and revision of the variable content, flow and hierarchy, and incentives for launching other complementary monitoring programs connected to NILS. They have also created a basis for a better and more user-oriented communication of results from NILS to different stakeholders.  相似文献   

20.
This study selected a petrochemical industrial complex in Beijing, China, to understand the characteristics of surface ozone (O3) in this industrial area through the on-site measurement campaign during the July–August of 2010 and 2011, and to reveal the response of local O3 to its precursors’ emissions through the NCAR-Master Mechanism model (NCAR-MM) simulation. Measurement results showed that the O3 concentration in this industrial area was significantly higher, with the mean daily average of 124.6 μg/m3 and mean daily maximum of 236.8 μg/m3, which are, respectively, 90.9 and 50.6 % higher than those in Beijing urban area. Moreover, the diurnal O3 peak generally started up early in 11:00–12:00 and usually remained for 5–6 h, greatly different with the normal diurnal pattern of urban O3. Then, we used NCAR-MM to simulate the average diurnal variation of photochemical O3 in sunny days of August 2010 in both industrial and urban areas. A good agreement in O3 diurnal variation pattern and in O3 relative level was obtained for both areas. For example of O3 daily maximum, the calculated value in the industrial area was about 51 % higher than in the urban area, while measured value in the industrial area was approximately 60 % higher than in the urban area. Finally, the sensitivity analysis of photochemical O3 to its precursors was conducted based on a set of VOCs/NOx emissions cases. Simulation results implied that in the industrial area, the response of O3 to VOCs was negative and to NOx was positive under the current conditions, with the sensitivity coefficients of ?0.16~?0.43 and +0.04~+0.06, respectively. By contrast, the urban area was within the VOCs-limitation regime, where ozone enhancement in response to increasing VOCs emissions and to decreasing NOx emission. So, we think that the VOCs emissions control for this petrochemical industrial complex will increase the potential risk of local ozone pollution aggravation, but will be helpful to inhibit the ozone formation in Beijing urban area through reducing the VOCs transport from the industrial area to the urban area.  相似文献   

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