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1.
对空气中甲醛测定的采样方法进行了探讨 ,分别用水和稀硫酸作吸收液对空气甲醛进行采样研究。结果表明 ,用 0 .0 0 5mol LH2 SO4 作吸收液的采样方法 ,可有效、稳定地延长样品的保存时间 ,且又符合方法灵敏度和精密度的要求。  相似文献   

2.
Estimating the Ecological Condition of the Estuaries of the Gulf of Mexico   总被引:1,自引:0,他引:1  
Monitoring of estuaries in the Louisianian Province was performed annually from 1991–1994 to assess ecological conditions on a regional scale. We found over the four years of monitoring, 25±6% of Gulf of Mexico estuarine sediments in the Louisianian Province displayed poor biological conditions, as measured by benthic community structure, and 14±7% of the area was characterized by poor water clarity, the presence of marine debris, and elevated levels of fish tissue contaminants. Using statistical associations to discern relationships between ecological condition and exposure or stressor data has shown that much of this degraded' condition co-occurs with sediment contamination.  相似文献   

3.
Substantial amounts of NOx (146 000 t/y) and total hydrocarbons (294 000 t/y) are released to the marine atmosphere by the large number of oil and gas operations over Federal waters of the Gulf of Mexico (GOM). Under appropriate meteorological conditions these emissions react to form ozone (0–54 g/m3 over-water) which can affect the marine environment. Using a dry deposition model, this work examines the amount of ozone derived from oil and gas offshore operations and deposited in the sea surface of the Gulf of Mexico, and assesses its impact on the neuston of the sea-surface microlayer. Surface integrated estimates of ozone deposited from oil and gas operations over the sea surface ranges from 400 kg to 1800 kg which results in sea surface concentrations of 15 g/m3. This estimate and the actual toxic ozone levels suggest no acute, toxic impacts to the neuston. However, indirect effects may occur through changes to the pelagic foodwebs and organic carbon pathways. Another potential pathway for ozone impacting the environment is through the production of bromate. Based on the concentrations and time scales (11–139 days) only sublethal effects appear to occur, but uncertainties associated with this assessment need to be further studied. From an ecological perspective, the environmental impacts and risks of NOx and VOC discharges from offshore platforms need to be assessed for neuston and other components of the marine ecosystem.  相似文献   

4.
为了解泰东河疏浚工程对通榆河水质的影响,于2012年6月8日、9月12日、12月6日,对泰东河沿线以及通榆河东台段进行调查取样,分析施工期间河体水质变化。结果表明,施工期间水质参数基本保持在Ⅱ~Ⅲ类。根据江苏省水环境监测中心盐城分中心2011年、2013年监测资料评价分析,泰东河河道疏浚后,清理了河床淤泥,提高了泰东河的行洪、抗洪以及通航能力,其水质的好转有效地改善了下游通榆河的水质,确保了饮水安全。  相似文献   

5.
The U.S. EPA has prepared a State of the Region Report for Mid-Atlantic Estuaries to increase knowledge of environmental condition for improved environmental management. Sources of information included the National Estuary Programs, the Chesapeake Bay Program, the state monitoring programs in Delaware, Maryland, and Virginia, Federal programs such as National Status & Trends, National Shellfish Register, National Wetlands Inventory, the Environmental Monitoring and Assessment Program, and other primary literature sources. The state of the estuarine environment was summarized using indicators for water and sediment quality, habitat change, condition of living resources, and aesthetic quality. Each indicator was briefly discussed relative to its importance in understanding estuarine condition. Wherever possible, data from multiple programs were used to depict condition. Finally, an overall evaluation of estuarine condition in the region was determined. The usefulness of monitoring programs that collect consistent information with a well-defined sampling design cannot be overemphasized.  相似文献   

6.
简述了锅炉的风量和烟气量、锅炉燃料的消耗量以及锅炉运行负荷的估算方法。通过实例分析,用现场监测的实际风量与理论值比较,粗略估算出监测时段锅炉运行负荷,比对锅炉污染物监测时段的锅炉运行负荷标准,从而判断监测数据的准确性与有效性。  相似文献   

7.
环境监控(监测)建设与发展过程的思考   总被引:7,自引:0,他引:7  
论述环境监控系统的发展过程、具体应用和建设的意义。叙述环境监控系统的建设为解决环境质量监测、污染源在线自动监测和生态监测与具体部门相关联而造成信息孤岛的问题,提倡环保多业务综合共享信息的标准化;环境监控系统的建设是基础,应用是关键,运行维护管理是保障,三者不可偏废。让环境管理者产生形象思维,拓宽思路和视野,发现和解决新问题。  相似文献   

8.
Introduction to the problem of environmental pollution caused by acid depositions. Presentation of principles of the six-year field experiment with simulated acid rain. Short characteristics of particular parts of the series of papers.  相似文献   

9.
能见度分级约束下的大气气溶胶光学厚度特征   总被引:4,自引:0,他引:4  
利用PIS太阳光谱仪观测了北京地区1993年3月—1995年3月晴天和少云天气的太阳直接辐射光谱,波长范围为0.40-1.04μm。光谱分辨率1.25nm,共有1064组数据。观测期间,将地面能见度分为五级。由太阳直射谱获得了各能见度下大气气溶胶光学厚度谱。研究表明,北京地区大气气溶胶光学厚度虽然其总体季节统计规律为春夏大,秋冬小,然而,当加入能见度分级约束后,各能见度下气溶胶光学厚度的季节变化,近于消失。这表明少数“反常”垂直结构不影响能见度分级的平均结果。而不分级的光学厚度季节起伏主要由各季节的几率能见度决定。文中还把年平均五种能见度下的光谱光学厚度与LOWTRAN模式作了对比。由光学厚度谱反演出了气溶胶粒子谱分布,为建立我国北方局地气溶胶模式构造了基本框架  相似文献   

10.
合江江段是长江上游干流保持河流生境、适宜喜流水性鱼类栖息的重要江段.为了掌握合江江段鱼类早期资源动态,分析向家坝水库生态调度的效果,于2020年向家坝水库生态调度前后,开展了鱼类早期资源逐日监测.研究期间,共采集到鱼类早期资源5目10科38种(属),其中仔鱼29种(属)、鱼卵19种(属),包括特有鱼类6种.广适应性和喜...  相似文献   

11.
12.
As part of the monitoring program from Instituto Hidrográfico, since 1981 sediment and water samples have been collected from four different estuarine areas located along the continental coast of Portugal. The concentrations of different parameters were measured in the water and sediment samples. After normalization, the concentrations of chromium, mercury, lead and zinc in the sediments from the different areas were compared.  相似文献   

13.
14.
太湖流域水体富营养化成因及防治对策的初步研究   总被引:16,自引:2,他引:16  
以较丰富的素材分析了太湖流域富营养化的成因及其危害性,同时阐述了水体富营养化的治理对策。  相似文献   

15.
Phytoplankton studies in early 1970s have shown the annual dominance of diatoms and a seasonal abundance of Trichodesmium in the lower reaches of the Cochin backwaters (CBW) and adjacent coastal Arabian Sea during the pre-summer monsoon period (February to May). Surprisingly, more recent literature shows a complete absence of Trichodesmium in the CBW after 1975 even though their seasonal occurrence in the adjacent coastal Arabian Sea continued without much change. In order to understand this important ecological feature, we analyzed the long-term water quality data (1965–2005) from the lower reaches of the CBW. The analyses have shown that salinity did not undergo any major change in the lower reaches over the years and values remained >30 throughout the period. In contrast, a tremendous increase was well marked in levels of nitrate (NO3) and phosphate (PO4) in the CBW after 1975 (av. 15 and 3.5 μM, respectively) compared with the period before (av. 2 and 0.9 μM, respectively). Monthly time series data collected in 2004–2005 period from the lower reaches of the CBW and coastal Arabian Sea have clearly shown that the physical characteristics like salinity, temperature, water column stability, and transparency in both regions are very similar during the pre-summer monsoon period. In contrast, the nutrient level in the CBW is several folds higher (NO3, 8; PO4, 4; SiO4, 10; and NH4, 19 μM) than the adjacent coastal Arabian Sea (NO3, 0.7; PO4, 0.5; SiO4, 0.9; and NH4, 0.6 μM). The historic and fresh time series data evidences a close coupling between enriched levels of nutrients and the absence of Trichodesmium in the Cochin backwaters  相似文献   

16.
Investigation indicates that the subsidence pattern in the lower Yangtze Delta area is related to groundwater extraction. Suzhou-Wuxi-Changzhou region ("Su-Xi-Chang") belongs to the hinterland of the lower Yangtze Delta that has a total area of 12,000 km2. From 1979 to 2000, long-term pumping of groundwater at Su-Xi-Chang has caused a rapid decline in groundwater table, resulting in large-scale land subsidence. In this paper, establishment of a GPS-based monitoring system for land subsidence using 30 years of data, is presented. The data were obtained through monitoring of 184 wells. Also analyzed herein is the relationship between the observed lowering of the groundwater table and subsidence. Monitoring data indicate that the depression cone of groundwater table and the occurrence of subsidence are basically identical in time and space. The generation of both features is attributed to excessive extraction of ground water in the region. Finally, countermeasures against subsidence are proposed.  相似文献   

17.
18.
利用单因子指数法和综合污染指数法,对乌鲁木齐市水磨河4个监测断面水质情况进行了评价。结果表明:搪瓷厂泉为超标水体;七纺桥为Ⅴ类水体,达到农业灌溉用水要求;联丰桥断面、米泉桥断面为劣Ⅴ类水体,没有达到农业灌溉用水要求。生活源和工业源化学需氧量、氨氮等污染物的排入对水体产生了严重影响,造成水体重污染。  相似文献   

19.
以南京为例,探讨以电子环保标志为载体,以射频识别技术构建机动车污染控制物联网体系,通过绿色智能交通系统、公交优先通行系统、高污染车限行执法系统、不同排放标准车辆的通行控制系统、机动车环保远程核查系统、交通污染智能监测在线调控系统、机动车污染联防联控系统、职能部门信息共享系统的建立,达到控制机动车污染、改善交通拥堵、提高...  相似文献   

20.
The assessment of the microbial diversity of the entire community of a given habitat requires the extraction of the total environmental DNA. Metagenomic investigations of a petroleum-polluted habitat have its unique challenges. The specific methods were developed for the extraction of high-quality metagenome in good quantity from the petroleum-polluted saline and non-saline sites in Gujarat (India). The soil samples were washed to remove the toxic, hazardous organic pollutants which might interfere with the recovery of the metagenomic DNA. The metagenomic DNA extraction results were encouraging with the mechanical bead beating, soft lysis, and combination of both. The extracted DNA was assessed for its purity and yield followed by its application in the amplification of the 16S rRNA region. The amplicons were used for judging the molecular diversity by the denaturing gradient gel electrophoresis (DGGE). The microbial diversity was also analyzed statistically by calculating various diversity indices and principal component analysis (PCA). The results on the metagenomic diversity of the bacterial population among the three cohorts based on the culture-independent technique exhibited significant difference among the PAH sites and Okha–Madhi and Porbandar Madhavpur habitats.  相似文献   

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