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1.
核设施外围环境γ辐射剂量率是环境保护工作中的重点监测对象。采用瞬时测量、热释光测量以及自动站连续测量3种方法分析了四川某核设施外围2011—2021年的环境γ辐射剂量率、周边居民辐射累积剂量以及这3种方法对监测结果的影响。结果表明,该核设施运行未对周围环境辐射水平造成显著影响;瞬时测量和自动站连续测量监测数据较为稳定,热释光测量易受周围环境影响造成数据波动。因此,在采用热释光测量法开展辐射环境监测时应加强对热释光剂量片布放、收取、运输、测量等环节的质量控制,并开展热释光剂量片宇宙射线响应值的测量。  相似文献   

2.
为了解环境空气臭氧累积规律,利用2017年沈阳市环境空气臭氧浓度数据,统计分析臭氧累积速率,并利用回归方法拟合并优化臭氧浓度及其累积速率的时间序列模型,同时结合气温、风力、臭氧前体物等时序变化情况分析臭氧浓度的影响因素。研究发现:沈阳市臭氧月均浓度年变化、日均浓度年变化以及小时浓度日变化时序曲线均呈现单峰形态;年变化中,6月的臭氧浓度最大,4月臭氧累积速率达到最大值;日变化中,14:00臭氧浓度达到最大值,09:00—11:00臭氧累积速率最大,19:00—20:00臭氧迅速消减。温度、风速同臭氧浓度之间均有较好的正相关性。臭氧前体物二氧化氮、挥发性有机物与臭氧浓度之间均呈明显的负相关性。  相似文献   

3.
为了掌握省辖市2003年以来空气自动监测系统的运行情况,根据几年的巡检,发现了一些影响空气自动监测系统运行的因素。本文主要从仪器、标准物质的使用、人员以及影响空气质量日报结果等几个方面进行了阐述,并提出了相应的改进措施,以期能对空气自动监测系统的管理提供借鉴。  相似文献   

4.
以环境中双壳类、鱼类及节肢类等水生生物为对象,介绍了其对微塑料的累积与清除,重点分析了微塑料特性、生物特性和食物等因素对微塑料生物累积与清除的影响,并进一步概述了微塑料沿水生食物链的传递效应,阐述了其对复合污染物食物链传递的影响过程。结果发现,微塑料在水生生物中的累积、清除与其自身尺寸、形态和聚合物类型等密切相关,水生生物的结构特异性是干扰微塑料从生物体内排泄的重要因素,有无食物的环境条件是调节双壳类和节肢类生物对微塑料累积与清除的重要路径;微塑料虽然可以通过食物链由低营养级向高营养级传递,但不一定会产生生物放大效应;微塑料的载体效应导致其复合污染物的食物链传递过程发生改变,共存污染物在生物体内的释放和吸收时间是调控微塑料复合污染物食物链传递能力的重要因素。  相似文献   

5.
二氧化硫甲醛吸收液动态稳定性的实验研究   总被引:1,自引:0,他引:1  
通过对测定大气中二氧化硫甲醛吸收液动态稳定性的研究,探讨了稳定性对24小时连续监测(手工采样)结果的影响及采样时间、流量和吸收液用量因素对监测结果影响的理论揭示。  相似文献   

6.
应用地累积指数法对珠江(广州河段)表层沉积物中重金属污染程度进行了调查与评价.结果表明,其表层沉积物中重金属的地累积指数大小顺序为:Cu>Cd>Zn>Pb>As>Cr>Hg,其中Cu是主要污染物,Cd、Zn和Pb的地累积指数较高.在所有监测断面中,地累积级别达到4级(强污染)的有5个断面,即4#(雅瑶大桥)、5#(黄歧)、6#(黄沙)、7#(横滘)和16#(花地涌北出口).  相似文献   

7.
水质监测采样的关键是保证样品具有代表性和完整性,是保证监测结果具有准确性、精密性和可比性的前提条件.本文就采样过程中存在的影响数据因素、措施及注意事项进行了探讨。  相似文献   

8.
建立水质自动监测系统的思考   总被引:1,自引:0,他引:1  
葛刚 《干旱环境监测》2000,14(4):226-229
结合章郭水质自动监测系统的可行性研究,在建立水质自动监测系统过程中对监测站位的选取、监测项目的选择、水质自动监测系统的组成、数据的采集与处理、系统的维护及管理、存在的问题等方面进行探讨,水质自动监测系统的建设可以弥补水质监测的不足,同时为实施总量控制及环境管理提供了可靠的依据。  相似文献   

9.
沉积物重金属污染评价——以巢湖龟山区为例   总被引:6,自引:1,他引:5  
文章系统介绍了水环境沉积物重金属污染评价方法,比较了不同评价方法的优缺点。采用地累积指数法和潜在生态风险法对巢湖龟山区沉积物中Pb、Cu、Zn、Cr等4种重金属污染进行了评价。结果表明,巢湖龟山区沉积物中金属Cr有中度生态风险,Cu有轻度污染,Pb和Zn没有污染。结果也说明,对沉积物中重金属污染的评价需要用多种方法进行比较评价。  相似文献   

10.
水环境中抗生素的分布、累积及生态毒理效应   总被引:3,自引:0,他引:3  
抗生素持续大量使用带来的环境污染和潜在的生态风险已经引起广泛关注。总结了国内外相关研究成果,对水环境中抗生素的污染源及残留水平进行了分析,对抗生素在水生生物体内的累积规律给予了评述,同时对抗生素的生态毒理效应进行了探讨。鉴于我国水环境中抗生素的污染现状,建议未来加强环境相关浓度下抗生素在生物体内的分布与转化、食物链迁移与放大,以及多种抗生素联合效应等方面的研究。  相似文献   

11.
Cumulative impact assessment (CIA) is the process of systematically assessing a proposed action's cumulative environmental effects in the context of past, present, and future actions, regardless of who undertakes such actions. Previous studies have examined CIA efforts at the federal level but little is known about how states assess the cumulative impacts of nonfederal projects. By examining state environmental review statutes, administrative rules, agency-prepared materials, and a national survey of the administrators of state environmental review programs, this study identifies the legal and administrative frameworks for CIA. It examines current CIA practice, discusses the relationship between CIA policy and its implementation, and explores the opportunities for improvement. The results of the study show that twenty-nine state environmental review programs across twenty-six states required the assessment of cumulative environmental impacts. More than half of these programs have adopted specific procedures for implementing their policies. Some programs assessed cumulative impacts using a standard review document, and others have created their own documentations incorporated into applications for state permits or funding. The majority of programs have adopted various scales, baselines, significance criteria, and coordination practices in their CIA processes. Mixed methods were generally used for data collection and analysis; qualitative methods were more prevalent than quantitative methods. The results also suggest that a program with comprehensive and consistent environmental review policies and procedures does not always imply extensive CIA requirements and practices. Finally, this study discusses the potential for improving existing CIA processes and promoting CIA efforts in states without established environmental review programs.  相似文献   

12.
The paper presents an evaluation of post-project impacts of the Barekese Dam on three riparian communities downstream about 30 years after its construction. A network diagram, which incorporated a mathematical model, was used for impact identification and analysis. The expected environmental impacts, expressed as quantitative weighted impact scores, showed that the dam appeared to have exerted adverse impacts on the environmental quality of the communities. The impacts in the communities, however, increased with relative distances away from the dam and the river suggestive of cumulative impacts transmitted downstream. Strategic measures for improving environmental quality of the communities have been given.  相似文献   

13.
Impact significance determination practice tends to be highly variable. Too often insufficient consideration is given to good practice insights. Also, impact significance determinations are frequently narrowly defined addressing, for example, only individual, negative impacts, focusing on bio-physical impacts, and not seeking to integrate either the Precautionary Principle or sustainability.This article seeks to extend the boundaries of impact significance determination practice by providing an overview of good general impact significance practices, together with stakeholder roles and potential methods for addressing significance determination challenges. Relevant thresholds, criteria, contextual considerations and support methods are also highlighted. The analysis is then extended to address how impact significance determination practices change for positive as compared with negative impacts, for cumulative as compared with individual impacts, for socio-economic as compared with bio-physical impacts, when the Precautionary Principle is integrated into the process, and when sustainability contributions drive the EIA process and related impact significance determinations. These refinements can assist EIA practitioners in ensuring that the scope and nature of impact significance determinations reflect the broadened scope of emerging EIA requirements and practices. Suggestions are included for further refining and testing of the proposed changes to impact significance determination practice.  相似文献   

14.
Effective ecological monitoring is imperative in a human-dominated world, as our ability to manage functioning ecosystems will depend on understanding biodiversity responses to anthropogenic impacts. Yet, most monitoring efforts have either been narrowly focused on particular sites, species and stressors — thus inadequately considering the cumulative effects of multiple, interacting impacts at scales of management relevance — or too unfocused to provide specific guidance. We propose a cumulative effects monitoring framework that integrates multi-scaled surveillance of trends in biodiversity and land cover with targeted evaluation of hypothesized drivers of change. The framework is grounded in a flexible conceptual model and uses monitoring to generate and test empirical models that relate the status of diverse taxonomic groups to the nature and extent of human “footprint” and other landscape attributes. An adaptive cycle of standardized sampling, model development, and model evaluation provides a means to learn about the system and guide management. Additional benefits of the framework include standardized data on status and trend for a wide variety of biodiversity elements, spatially explicit models for regional planning and scenario evaluation, and identification of knowledge gaps for complementary research. We describe efforts to implement the framework in Alberta, Canada, through the Alberta Biodiversity Monitoring Institute, and identify key challenges to be addressed.  相似文献   

15.
选取北京市近5年夏半年(4—9月)的降雨数据及相关噪声自动监测小时等效声级,利用数学统计软件进行有雨-无雨声级差异性分析、声级-降雨相关性分析及平均声级-雨量变化趋势分析等,提出降雨确实对噪声自动监测小时数据有一定贡献,不同雨量对不同功能区噪声影响不同,建议噪声自动监测系统建设时应考虑雨噪声影响,以保证对声环境质量评价的科学性和准确性。  相似文献   

16.
Swine Concentrated Animal Feeding Operations (CAFOs) have received much attention in recent years. As a result, a watershed-based screening tool, the Cumulative Risk Index Analysis (CRIA), was developed to assess the cumulative impacts of multiple CAFO facilities in a watershedsubunit. The CRIA formula calculates an index number based on: 1) the area of one or more facilities compared to the area of the watershed subunit, 2) the average of the environmental vulnerability criteria, and 3) the average of the industry-specific impact criteria. Each vulnerability or impact criterion is ranked on a 1 to 5 scale, with a low rank indicating low environmental vulnerability or impact and a high rank indicating high environmental vulnerability or impact. The individual criterion ranks, as well as the total CRIA score, can be used to focus the environmental analysis and facilitate discussions with industry, public, and other stakeholders in the Agency decision-making process.  相似文献   

17.
The Timber, Fish, and Wildlife program (TFW) in Washington is a consensus approach to implementing reforms in forest practice regulations involving industrial timberland owners, state agencies, environmental groups, Indian tribes, and non-industrial forest landowners. A cooperative monitoring and research effort (CMER) has been included as a part of this program. Technical projects undertaken by CMER are overseen by a series of steering committees, one of which is the Water Quality Steering Committee. Projects currently being addressed by the Water Quality Steering Committee include: forestry impacts on water temperature, water quality impacts from forestry derived sediment, use of bio-indicators to assess the water quality impacts of forest practices, and the effect of forest chemical applications on water quality. A close link between the research efforts in TFW and the procedure for implementing regulatory change has greatly improved the responsiveness of the rule making process to new information. Results from the water temperature and forest chemical work is currently being incorporated into the forest practice regulations.  相似文献   

18.
An ambient air quality monitoring network has been establishedusing risk assessment techniques to evaluate adverse health effects from exposures to airborne contaminants. The risk assessment method was compared to traditional methods of establishing air quality monitoring networks: identifying maximumconcentration impacts or maximum total population. Results suggest that the health risk method best predicted the locationof adverse, non-carcinogenic respiratory illnesses during the evaluation period. Spearman Rank Correlation Coefficient, r s, values obtained using the risk assessment method werestatistically greater than the values obtained using theconcentration and population methods. The concentration methodwas the least accurate predictor of adverse effects.  相似文献   

19.
Published guidelines for Cumulative Effects Assessment (CEA) have called for the identification of cause-and-effect relationships, or causality, challenging researchers to identify methods that can possibly meet CEA's specific requirements. Together with an outline of these requirements from CEA key literature, the various definitions of cumulative effects point to the direction of a method for causality analysis that is visually-oriented and qualitative. This article consequently revisits network and system diagrams, resolves their reported shortcomings, and extends their capabilities with causal loop diagramming methodology. The application of the resulting composite causality analysis method to three Environmental Impact Assessment (EIA) case studies appears to satisfy the specific requirements of CEA regarding causality. Three “moments” are envisaged for the use of the proposed method: during the scoping stage, during the assessment process, and during the stakeholder participation process.  相似文献   

20.
An investigation of the impacts from elevated intertidal Pacific oyster culture in a New Zealand estuary showed enhanced sedimentation beneath culture racks compared with other sites. Seabed elevation beneath racks was generally lower than between them, suggesting that topographic patterns more likely result from a local effect of rack structures on hydrodynamic processes than from enhanced deposition. Compared with control sites, seabed sediments within the farm had a greater silt/clay and organic content, and a lower redox potential and shear strength. While a marked trend in macrofaunal species richness was not evident, species composition and dominance patterns were consistent with a disturbance gradient, with farm effects not evident 35 m from the perimeter of the racks. Of the environmental variables measured, sediment shear strength was most closely associated with the distribution and density of macrofauna, suggesting that human-induced disturbance from farming operations may have contributed to the biological patterns. To evaluate the taxonomic sufficiency needed to document impacts, aggregation to the family level based on Linnean classification was compared with an aggregation scheme based on `general groups' identifiable with limited taxonomic expertise. Compared with species-level analyses, spatial patterns of impact were equally discernible at both aggregation levels used, provided density rather than presence/absence data were used. Once baseline conditions are established and the efficacy of taxonomic aggregation demonstrated, a `general group' scheme provides an appropriate and increasingly relevant tool for routine monitoring.  相似文献   

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