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1.
构建符合上海市土壤特征的污染土壤环境质量评价标准体系,可以有效指导上海市污染土壤的风险评估和修复工作。介绍了国外土壤环境质量评价标准体系构建的现状,分析了中国土壤环境质量评价标准体系的特点和不足,以《展览会用地土壤环境质量评价标准》(暂行)(HJ/T 350—2007)为基础,建议在制订土壤环境质量指导值时,根据上海市规划特点选择敏感受体和土地利用类型,并结合上海市污染土壤背景选择关注污染物及暴露途径;建议根据修复技术、修复模式(原位修复或异位修复)和修复后土壤去向制订土壤修复标准。同时,建议在上海市污染土壤环境质量评价标准体系构建过程中,充分考虑中国仪器分析水平,并加强相关法律法规建设,确保标准体系的有效应用。  相似文献   

2.
以天津市医疗废物管理现状为研究对象,对处置方式进行深入探讨,分析目前分散处置和集中处置存在的缺陷,提出"区域集中处置"设想;并运用模糊决策模型理论,建立较完善的处置方式评价指标体系,应用模糊综合评价模型得出"区域集中处置"是最佳的医疗废物处置方式,同时提出了相应的区域集中处置策略.  相似文献   

3.
近年来我国城镇污水处理厂的修建得到很大发展,但其在运行管理方面存在一些问题,为了促进污水处理厂的稳定运行与升级改造,需要建立一套综合绩效评价体系对其进行科学的评价与管理。在对城镇污水处理厂的调查研究基础上,提出将DPSIR原理融入到城镇污水处理厂综合绩效评价指标体系的构造中,形成了一个3层19个指标的综合绩效评价指标体系,通过层次分析法(AHP)和模糊综合评价法相结合,创建了城镇污水处理厂综合绩效的AHP-模糊综合评价模型,并选取成都市两座(A和B)城镇污水处理厂展开实例应用研究。结果表明:A污水处理厂综合绩效评价结果有26.3%隶属于"较好"等级,B污水处理厂综合绩效评价结果有28.1%隶属于"一般"等级。根据最大隶属度原则,A和B污水处理厂综合绩效评价等级分别属于"较好"和"一般"。  相似文献   

4.
一九七八年至一九七九年对北戴河风景区土壤开展了两次调查,在调查基础上,对本区土壤重金属的环境质量评价做了尝试。此评价从北戴河风景区土壤实际情况出发,在传统综合评价方法的基础上,对土壤环境质量综合评价的标准、权重、标准化方法、重金属毒性及环境质量等级等问题,进行了探索,力图避免评价中的主观性和任意性。实践证明,这种方法收到了比较好的效果。 通过对北戴河风景区土壤重金属含量的调查,获得了大量的数据,对该区土壤中重金属含量状况有了一些了解。这些调查数据,是评价该区重金属污染状况的基础。但是,在应用综合评价方法,评价土壤环境质量时,如何选择适宜的评价标准,应用恰当的评价模式,确定客观的权系数,划分妥当的土壤环境质量等级,这是关系到评价结果的可信赖性和真实性的重要问题。然而,到目前为止,国内外还没有一个统一的评价方法和评价标准,作为土壤环境质量评价的一些基础性工作,跟不上实际需要,因而在处理上述问题时,往往采用相对比较方法,带有很大的主观性,这在一定程度上影响了评价的效果。随着环境保护工作的深入开展,要求尽快摆脱评价工作中的主观性因素,提高评价结果的质量。因而在北戴河风景区土壤环境质量评价研究中,首先对一些基本方法问题,进行了初步尝式,并以此对北戴  相似文献   

5.
制浆造纸中段水处理工艺优选属于多方案、多指标的综合评价问题,本研究在模糊物元分析的基础上,结合优选理论中贴近度的概念,建立了制浆造纸中段水处理工艺优选的欧氏贴近度模糊物元分析法(FMEA),并通过均方差法确定指标权重。通过建立评价指标体系,从技术性能、经济费用和管理效果3个方面对传统活性污泥法、完全混合活性污泥法、氧化沟法和序批式活性污泥法(SBR)进行评价,结果表明,SBR法技术性能和经济费用最优,氧化沟法管理效果和综合评价最优,为不同条件下优选制浆造纸中段水处理工艺提供了参考依据。  相似文献   

6.
自然灾害、城镇扩展及人类活动干扰在很大程度上影响着海岸带生态安全。归纳了国内外海岸带生态安全的研究热点,国内主要集中在生态安全管理、评估、格局规划3个方面,国外学者侧重于研究海岸带综合管理、环境演化及灾害预测、生态系统健康评价、风险评价等方面。生态安全评估是实施生态环境管理与保护行动的基础工作,但国内外现有研究中对海岸带生态安全的评估还没有统一的标准。针对海岸带生态安全的特点,对比相关概念模型、评价方法的优缺点,采用指标重要值的方法确定了海岸带生态安全评估指标的重要性程度。最后,基于"驱动力—压力—状态—响应"概念框架模型,提出海岸带生态安全评估的指标体系框架,以期为海岸带生态安全评估提供参考。  相似文献   

7.
以天津市医疗废物管理现状为研究对象,对处置方式进行深入探讨,分析目前分散处置和集中处置存在的缺陷,提出“区域集中处置”设想;并运用模糊决策模型理论,建立较完善的处置方式评价指标体系,应用模糊综合评价模型得出“区域集中处置”是最佳的医疗废物处置方式,同时提出了相应的区域集中处置策略。  相似文献   

8.
为了减轻城市噪声对人们日常生活带来的影响,提高城市噪声管理的水平及科学性,对城市声环境功能区中一、二类混合区域的划分进行了研究。针对"混合区"划分过程中存在的模糊性特点,运用模糊综合评价原理,选取适当的评价指标,引入"三标度法"确定了各指标的权重,并结合GIS技术的空间数据采集、储存、管理、查询和分析能力,建立GIS模糊综合评价模型,实现了城市声功能"混合区"的批量划分及可视化,最后将模型应用于某市的声环境功能区划分中,使划分结果更科学、客观。  相似文献   

9.
水产养殖规划环境影响评价关键指标的研究   总被引:1,自引:0,他引:1  
建立水产养殖规划环境影响评价指标体系的实质就是建立其环境影响的具体评价内容.提出了水产养殖规划显著环境影响识别的必要性和方法,引入了关键控制点的概念和识别方法,提出了建立关键指标体系的方法.同时,根据水产养殖规划环境影响评价的要求,提出了规划层次的评价指标和水环境状态反应层次指标的两级指标结构层次.  相似文献   

10.
收集了研究区内2008年的历史数据和2018年采集的最新数据,共计278个样品,分析测试了土壤环境污染常提及的Cd、Hg、As、Pb、Cr、Cu、Ni、Zn共8类重金属元素,利用单因子指数评价法、内梅罗综合污染指数法以及土壤环境质量评估法评价研究区内西河和耒水2条河流周边的土壤环境质量类别,结合反距离空间插值法以及空间几何分析,直观地展示出研究区2008—2018年土壤重金属的时空变异特征。结果表明:采集的2期数据中除Cr外,Cd、Hg、As、Pb、Cu、Ni、Zn表层土壤重金属元素均存在点位超标的情况,说明该研究区中整体存在重金属污染;通过单因子指数评价可知,2期数据单因子指数平均值排前2位的均为Cd和Pb,Cr平均值最小,研究区内2期数据Cr超过98%点位均属于优先保护类点位,Cd、As、Pb均存在超过《土壤环境质量农用地土壤污染风险管控标准》(GB 15618-2018)管制值的点位;污染增强区主要分布于采矿及冶炼企业密度较大的西河中上游、耒水上游和耒水下游3个区。为防止今后土壤重金属污染进一步增强,建议对3个高值区采取恰当的管理措施。  相似文献   

11.
Abstract

The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for 3H, 90Sr, 137Cs, totU, 238Pu, 239,240Pu, and 241Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of 90Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g‐1 [126E‐02 Bq kg‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g‐1 [518E‐02 Bq kg‐1]). The differences in 90Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y‐1 (1.0 ± 1.0 μSv y‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y‐1 (1000 μSv y‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.  相似文献   

12.
We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.  相似文献   

13.
Abstract

This paper summarizes radionuclide concentrations (3H, 90Sr, 137Cs, 238Pu, 239,240Pu, 241Am, and totU) in muscle and bone tissue of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) collected from Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, lands from 1991 through 1998. Also, the committed effective dose equivalent (CEDE) and the risk of excess cancer fatalities (RECF) to people who ingest muscle and bone from deer and elk collected from LANL lands were estimated. Most radionuclide concentrations in muscle and bone from individual deer (n = 11) and elk (n = 22) collected from LANL lands were either at less than detectable quantities (where the analytical result was smaller than two counting uncertainties) and/or within upper (95%) level background (BG) concentrations. As a group, most radionuclides in muscle and bone of deer and elk from LANL lands were not significantly higher (p<0.10) than in similar tissues from deer (n = 3) and elk (n = 7) collected from BG locations. Also, elk that had been radio collared and tracked for two years and spent an average time of 50% on LANL lands were not significantly different in most radionuclides from road kill elk that have been collected as part of the environmental surveillance program. Overall, the upper (95%) level net CEDEs (the CEDE plus two sigma for each radioisotope minus background) at the most conservative ingestion rate (50 lbs of muscle and 13 lbs of bone) were as follows: deer muscle = 0.22 mrem y‐1 (2.2 μSv y‐1), deer bone = 3.8 mrem y‐1 (38 μSv y‐1), elk muscle = 0.12 mrem y‐1 (1.2 μSv y‐1), and elk bone = 1.7 mrem y‐1 (17 μSv y‐1). All CEDEs were far below the International Commission on Radiological Protection guideline of 100 mrem y‐1 (1000 μSv y‐1), and the highest muscle plus bone net CEDE corresponded to a RECF of 2E‐06, which is far below the Environmental Protection Agency upper level guideline of 1E‐04.  相似文献   

14.
This study aimed to evaluate the leaching of pesticides and the applicability of the Attenuation Factor (AF) Model to predict their leaching. The leaching of carbofuran, carbendazim, diuron, metolachlor, α and β endosulfan and chlorpyrifos was studied in an Oxisol using a field experiment lysimeter located in Dom Aquino – Mato Grosso. The samples of percolated water were collected by rain event and analyzed. Chemical and physical soil attributes were determined before pesticide application to the plots. The results showed that carbofuran was the pesticide that presented a higher leaching rate in the studied soil, so was the one representing the highest contamination potential. From the total carbofuran applied in the soil surface, around 6 % leached below 50 cm. The other pesticides showed lower mobility in the studied soil. The calculated values to AF were 7.06E-12 (carbendazim), 5.08E-03 (carbofuran), 3.12E-17 (diuron), 6.66E-345 (α-endosulfan), 1.47E-162 (β-endosulfan), 1.50E-06 (metolachlor), 3.51E-155 (chlorpyrifos). AF Model was useful to classify the pesticides' potential for contamination; however, that model underestimated pesticide leaching.  相似文献   

15.
Endosulfan in China 2—emissions and residues   总被引:4,自引:0,他引:4  
Background, aim, and scope  Endosulfan is one of the organochlorine pesticides (OCPs) and also a candidate to be included in a group of new persistent organic pollutants (UNEP 2007). The first national endosulfan usage inventories in China with 1/4° longitude by 1/6° latitude resolution has been reported in an accompanying paper. In the second part of the paper, we compiled the gridded historical emissions and soil residues of endosulfan in China from the usage inventories. Based on the residue/emission data, gridded concentrations of endosulfan in Chinese soil and air have been calculated. These inventories will provide valuable data for the further study of endosulfan. Methods  Emission and residue of endosulfan were calculated from endosulfan usage by using a simplified gridded pesticide emission and residue model—SGPERM, which is an integrated modeling system combining mathematical model, database management system, and geographic information system. By using the emission and residue inventories, annual air and soil concentrations of endosulfan in each cell were determined. Results and discussion  Historical gridded emission and residue inventories of α- and β-endosulfan in agricultural soil in China with 1/4° longitude by 1/6° latitude resolution have been created. Total emissions were around 10,800 t, with α-endosulfan at 7,400 t and β-endosulfan at 3,400 t from 1994 to 2004. The highest residues were 140 t for α-endosulfan and 390 t for β-endosulfan, and the lowest residues were 0.7 t for α-endosulfan and 170 t for β-endosulfan in 2004 in Chinese agricultural soil where endosulfan was applied. Based on the emission and residue inventories, concentrations of α- and β-endosulfan in Chinese air and agricultural surface soil were also calculated for each grid cell. We have estimated annual averaged air concentrations and the annual minimum and maximum soil concentrations across China. The real concentrations will be different from season to season. Although our model does not consider the transport of the insecticide in the atmosphere, which could be very important in some areas during some special time, the estimated concentrations of endosulfan in Chinese air and soil derived from the endosulfan emission and residue inventories are in general consistent with the published monitoring data. Conclusions  To our knowledge, this work is the first inventory of this kind for endosulfan published on a national scale. Concentrations of the chemical in Chinese air and agricultural surface soil were calculated for each grid cell. Results show that the estimated concentrations of endosulfan in Chinese air and soil agree reasonably well with the monitoring data in general. Recommendations and perspectives  The gridded endosulfan emission/residue inventories and also the air and soil concentration inventories created in this study will be updated upon availability of new information, including usage and monitoring data. The establishment of these inventories for the OCP is important for both scientific communities and policy makers.  相似文献   

16.
This study is aimed at investigating the impact of water quality on the uptake and distribution of three non-essential and toxic elements, namely, As, Cd and Pb in the watercress plant to assess for metal toxicity. The plant was hydroponically cultivated under greenhouse conditions, with the growth medium being spiked with varying concentrations of As, Cd and Pb. Plants that were harvested weekly for elemental analysis showed physiological and morphological symptoms of toxicity on exposure to high concentrations of Cd and Pb. Plants exposed to high concentrations of As did not survive and the threshold for As uptake in watercress was established at 5 ppm. Translocation factors were low in all cases as the toxic elements accumulated more in the roots of the plant than the edible leaves. The impact of Zn on the uptake of toxic elements was also evaluated and Zn was found to have an antagonistic effect on uptake of both Cd and Pb with no notable effect on uptake of As. The findings indicate that phytotoxicity or death of the watercress plant would prevent it from being a route of human exposure to high concentrations of As, Cd and Pb in the environment.  相似文献   

17.
Concentrations of mono- (MBT), di- (DBT), and tri-(TBT) butyltin compounds were measured in eggs, liver, and muscle of nine species of fish from four regions of the Baltic Sea - the Firth of Vistula, the Gulf of Gdańsk, Puck Bay, and the mouth of the Vistula River. The overall concentration ranges among all the fish sampled from the four sites were: < 7 to 79 ng/g for MBT, 6 to 1100 ng/g for DBT, 7 to 3600 ng/g for TBT, and 16 to 4800 ng/g for total BTs, on a wet wt basis. The highest concentration of total BTs was found in herring liver from the Firth of Vistula (4800 ng/g, wet wt) and in roach muscle from Puck Bay (3300 ng/g, wet wt), while the least concentration was found in burbot eggs and liver from the Vistula River (39 and 32 ng/g, wet wt, respectively). TBT was the major form of BTs present in most samples analyzed. Sediment samples collected from shipyards in the Gulf of Gdańsk contained butyltin concentrations ranging from 1.2 to 46 μg/g (dry wt) for MBT, 2.0 to 42 μg/g for DBT, and 2.6 to 40 μg/g for TBT. As with the fish, the majority of the BTs in sediment were present as TBT, which suggested recent exposure of the aquatic environment of the region to TBT.  相似文献   

18.
19.
The effect of malathion [diethyl(dimethoxythiophosphorylthio)succinate] at sublethal concentration (0.006 ppm) on hematological parameters of the cricket frog (Fejervarya limnocharis) was studied for 24 hrs to 240 hrs of exposure and remarkable hematological alterations were observed. The study on hematological parameters revealed a highly significant decrease (P < 0.01) in the total erythrocytes count in malathion-exposed animals from 24 hours to 96 hrs of exposure as compared to control. Significant decreases (P < 0.01) of hemoglobin and packed cell volume were also observed from 48 hrs to 240 hrs. A significant increase (P < 0.01) in leucocytes count was noted throughout the exposure period. Elevated numbers of lymphocytes and eosinophils as found in the present study revealed lymphocytosis as well as eosinophilia, suggesting that this was a result of direct stimulation of the immunological defense due to the presence of a toxic substance or may be associated with tissue damage. The cytomorphological and cytopathological study of erythrocytes and leucocytes in malathion-exposed frogs at 0.006 ppm concentration revealed various cytotoxic effects at different exposure times. It was noted that the size and the shape of the erythrocytes were subjected to variation in different blood disorders.  相似文献   

20.
Several monitoring programs have been set up to assess effects of atmospheric deposition on forest ecosystems. The aim of the present study was to evaluate effects on the understorey vegetation, based on the first round of a regional (the Netherlands) and a European forest monitoring program. A multivariate statistical analysis showed surprisingly similar results for both data sets; the vegetation appeared to be largely determined by the ‘traditional’ factors soil, climate, and tree species, but there was a small but statistically significant effect of atmospheric deposition. The effects of deposition include a slight shift towards nitrophytic species at high N deposition in the European network, and towards acidophytic species at high S-deposition in the Dutch network. The relatively small effect of atmospheric deposition is understandable in view of the very large natural variation in environmental conditions. Time series of both vegetation and environment are needed to assess deposition effects in detail.  相似文献   

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