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901.
Steven C. Schimmel Sandra J. Benyi Charles J. Strobel 《Environmental monitoring and assessment》1999,56(1):27-49
Data from the Environmental Protection Agency's (EPA) Environmental Monitoring and Assessment Program (EMAP) from 1990 to 1993 were used to assess the condition of the Long Island Sound (LIS) estuary. Ambient water, sediment and biota were collected during the summer months from 53 LIS stations using an unbiased sampling design. The design consists of two LIS subunits, LIS proper, and small estuaries (<2.6 km2) at the margins of the Sound. Selected indicators of condition included: benthic species composition, abundance and biomass; fish species composition and gross external pathology; sediment physical and chemical characterization and sediment toxicity; and water clarity and quality. Results of the four-year sampling indicated that 28(±11)% of the areal extent of LIS proper had a benthic index < zero (impacted) and 51(±12)% of the area of small estuaries was impacted. Analysis of the results of other indicators also shows that small estuaries were particularly affected. For example, 42(±10)% of the areal extent of small estuaries exhibited sediment toxicity, and significant chemical contamination was evident in 22% of the area of small estuaries. Low dissolved oxygen (D.O.) concentrations (<5 ppm), however, appeared to affect only the deeper open waters of western LIS. Approximately 48(±12)% of the areal extent of LIS proper documented exposure to at least moderate D.O. stress (<5 ppm). The overall results of this monitoring study indicate that significant anthropogenic impacts have occurred in LIS and that if remediation was to take place, specific localized sediment problems would need attention. Point source and non-point source nutrient inputs to the Sound, which are believed to be the primary causative factor for the observed hypoxic conditions, would also need attention. 相似文献
902.
环境质量综合评价方法的改进 总被引:14,自引:1,他引:13
分析了环境质量综合评价方法的不足之处,引入了等级分数矩阵和环境评价值,提出了最小隶属原则,建立了改进的环境质量综合评价模型。 相似文献
903.
主动为环境监督管理服务 总被引:1,自引:0,他引:1
分析了一些县级监测站存在的只注重监测数据,缺乏主动为环境管理服务的思想,介绍了海门市则站主动为环境管理及时提供的监测数据,促进了环境监督管理。 相似文献
904.
鉴于目前环境影响预测中基准值取法存在的问题,提出了结合目前通用做法与灰色预测的灰靶方案,该方案使得环境影响预测结果在一定范围内变化,从而更为切合评价实际。 相似文献
905.
Nam JJ Gustafsson O Kurt-Karakus P Breivik K Steinnes E Jones KC 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):809-817
Black carbon (BC) and total organic carbon (TOC) contents of UK and Norwegian background soils were determined and their relationships with persistent organic pollutants (HCB, PAHs, PCBs, co-planar PCBs, PBDEs and PCDD/Fs) investigated by correlation and regression analyses, to assess their roles in influencing compound partitioning/retention in soils. The 52 soils used were high in TOC (range 54-460 mg/g (mean 256)), while BC only constituted 0.24-1.8% (0.88%) of the TOC. TOC was strongly correlated (p < 0.001) with HCB, PCBs, co-PCBs and PBDEs, but less so with PCDD/Fs (p < 0.05) and PAHs. TOC explained variability in soil content, as follows: HCB, 80%; PCBs, 44%; co-PCBs, 40%; PBDEs, 27%. BC also gave statistically significant correlations with PBDEs (p < 0.001), co-PCBs (p < 0.01) and PCBs, HCB, PCDD/F (p < 0.05); TOC and BC were correlated with each other (p < 0.01). Inferences are made about possible combustion-derived sources, atmospheric transport and air-surface exchange processes for these compounds. 相似文献
906.
Modulation of steroidogenesis by coastal waters and sewage effluents of Hong Kong, China, using the H295R assay 总被引:2,自引:1,他引:1
Gracia T Jones PD Higley EB Hilscherova K Newsted JL Murphy MB Chan AK Zhang X Hecker M Lam PK Wu RS Giesy JP 《Environmental science and pollution research international》2008,15(4):332-343
BACKGROUND, AIM, AND SCOPE: The presence of a variety of pollutants in the aquatic environment that can potentially interfere with the production of sex steroid hormones in wildlife and humans has been of increasing concern. The aim of the present study was to investigate the effects of extracts from Hong Kong marine waters, and influents and effluents from wastewater treatment plants on steroidogenesis using the H295R cell bioassay. After exposing H295R cells to extracts of water, the expression of four steroidogenic genes and the production of three steroid hormones were measured. MATERIALS AND METHODS: Water samples were collected during the summer of 2005 from 24 coastal marine areas and from the influents and effluents of two major waste water treatment plants (WWTPs) in Hong Kong, China. Samples were extracted by solid phase extraction (SPE). H295R cells were exposed for 48 h to dilutions of these extracts. Modulations of the expression of the steroidogenic genes CYP19, CYP17, 3betaHSD2, and CYP11beta2 were determined by measuring mRNA concentrations by real-time polymerase chain reaction (Q-RT-PCR). Production of the hormones progesterone (P), estradiol (E2), and testosterone (T) was quantified using enzyme linked immunosorbent assays (ELISA). RESULTS: Extracts from samples collected in two fish culture areas inhibited growth and proliferation of H295R cells at concentrations greater or equal to 10(5) L equivalents. The cells were exposed to the equivalent concentration of active substances in 10,000 L of water. Thus, to observe the same level of effect as observed in vitro on aquatic organisms would require a bioaccumulation factor of this same magnitude. None of the other 22 marine samples affected growth of the cells at any dilution tested. Twelve of the marine water samples completely inhibited the expression of CYP19 without affecting E2 production; inhibition of CYP17 expression was observed only in one of the samples while expression of CYP11beta2 was induced as much as five- and ninefold after exposure of cells to extracts from two locations. The expression of the progesterone gene 3betaHSD2 was not affected by any of the samples; only one sample induced approximately fourfold the production of E2. Although more than twofold inductions were observed for P and T production, none of these values were statistically significant to conclude effects on the production of these two hormones. While influents from WWTPs did not affect gene expression, an approximately 30% inhibition in the production of E2 and a 40% increase in P occurred for the exposure with influents from the Sha Tin and Stonecutters WWTPs, respectively. Effluents from WWTPs did not affect the production of any of the studied hormones, but a decrement in the expression of the aldosterone gene CYP11beta2 was observed for the Sha Tin WWTP exposure. No direct correlation could be established between gene expression and hormone production. DISCUSSION: Observed cytotoxicity in the two samples from fish culture areas suggest the presence of toxic compounds; chemical analysis is required for their full identification. Although effluents from WWTPs did not affect hormone production, other types of endocrine activity such as receptor-mediated effects cannot be ruled out. Interactions due to the complexity of the samples and alternative steroidogenic pathways might explain the lack of correlation between gene expression and hormone production results. CONCLUSIONS: Changes observed in gene expression and hormone production suggest the presence in Hong Kong coastal waters of pollutants with endocrine disruption potential and others of significant toxic effects. The aromatase and aldosterone genes seem to be the most affected by the exposures, while E2 and P are the hormones with more significant changes observed. Results also suggest effectiveness in the removing of compounds with endocrine activity by the WWTPs studied, as effluent samples did not significantly affect hormone production. The H295R cell showed to be a valuable toll in the battery required for the analysis of endocrine disrupting activities of complex environmental samples. RECOMMENDATIONS AND PERSPECTIVES: Due to the intrinsic complexity of environmental samples, a combination of analytical tools is required to realistically assess environmental conditions, especially in aquatic systems. In the evaluation of endocrine disrupting activities, the H295R cell bioassay should be used in combination with other genomic, biological, chemical, and hydrological tests to establish viable modes for endocrine disruption and identify compounds responsible for the observed effects. 相似文献
907.
运用博弈论和利益相关理论构建的环境保护利益博弈分析框架,剖析长寿湖渔业养殖污染中的利益相关者及其博弈。通过分析政府、企业、渔民之间的六种利益博弈形式,得出结论:在渔场的各种利益博弈中,渔民的驱利行为导致了长寿湖的“公地悲剧”;守法成本高于违法成本是环境执法不力的主要原因;对渔场企业的环境管理职能缺乏有效的激励和约束;现行的政绩考核制度导致政府部门在环境保护行为中政治利益失衡;环保政策必须与相应经济利益挂钩,用激励机制把环保内化为自觉的经济行为;合理引导环境主体的群体行为,会使环保工作更加有效开展。 相似文献
908.
909.
审时度势创新发展全方位推进环境监测现代化建设 总被引:5,自引:8,他引:5
柏仇勇 《环境监测管理与技术》2006,18(1):1-5
回顾了环境监测的发展历程,指出环境监测还面临着定位不明、服务单一、投入不足、监测能力建设滞后的问题。阐述了环境监测现代化建设的总体目标和要求,提出面向“十一五”,围绕建设环境友好型社会、构建和谐社会的时代要求,环境监测必须抓住战略发展机遇,努力开拓创新,健全法制,理顺体制,多元投入。激活机制。强化科研。拓展领域,增强能力。发展事业。全方位推进现代化建设。 相似文献
910.
指出了环境监测机构存在的问题,提出环境监测机构体制改革应从3方面考虑:机构改革应实行垂直管理,政,事分开,职能改革应体现环境监测站以环境质量监测为基本职能;内部管理改革需建立以聘任制为基础的用人制度,岗位管理和竞争上岗制度,适当的分配激励机制。 相似文献