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131.
新污染物监测是新污染物环境和健康风险评估及管控的重要基础。欧美发达国家环保部门在20世纪70年代就开展了新污染物监测工作,并且2000年后形成了相应的监测制度,而我国新污染物监测工作正处于业务化起步阶段。通过深入调研欧美国家水中新污染物监测为主的发展历程、监测清单、监测要求等内容,总结出3个特点:建立动态更新的新污染物清单监测机制;将规范的新污染物监测方法作为开展监测的重要前提;充分考虑监测可行性和经济成本。结合我国现阶段新污染物监管需求及监测现状,提出我国新污染物监测工作的3点建议:明晰国家、地方新污染物监测的职责分工,建立优先监测新污染物清单动态更新机制;加强新污染物监测能力建设,建立新污染物监测标准体系;循序渐进开展新污染物监测,注重监测的可行性和可持续性。  相似文献   
132.
天津经济技术开发区(TEDA)环境预警系统的建立研究   总被引:9,自引:0,他引:9  
本文通过对警系统的分析,指出环境预警系统是多目标系统,其包含对某一时点和某段时间变化 趋势的报警。  相似文献   
133.
This paper presents the results of the Environmental Monitoring Program for the Radioactive waste repository of Abadia de Goiás, which was originated from the accident of Goiania, conducted by the Regional Center of Nuclear Sciences (CRCN-CO) of the National Commission on Nuclear Energy (CNEN), from 1998 to 2008.The results are related to the determination of 137Cs activity per unit of mass or volume of samples from surface water, ground water, depth sediments of the river, soil and vegetation, and also the air-kerma rate estimation for gamma exposure in the monitored site.In the phase of operational Environmental Monitoring Program, the values of the geometric mean and standard deviation obtained for 137Cs activity per unit of mass or volume in the analyzed samples were (0.08 ± 1.16) Bq.L−1 for surface and underground water, (0.22 ± 2.79) Bq.kg−1 for soil, and (0.19 ± 2.72) Bq.kg−1 for sediment, and (0.19 ± 2.30) Bq.kg−1 for vegetation. These results were similar to the values of the pre-operational Environmental Monitoring Program.With these data, estimations for effective dose were evaluated for public individuals in the neighborhood of the waste repository, considering the main possible way of exposure of this population group.The annual effective dose obtained from the analysis of these results were lower than 0.3 mSv.y−1, which is the limit established by CNEN for environmental impact in the public individuals indicating that the facility is operating safely, without any radiological impact to the surrounding environment.  相似文献   
134.
Dang Z  Traas T  Vermeire T 《Chemosphere》2011,85(10):1592-1603
In a fish testing strategy, positive results of the fish short term reproduction assay (FSTR), often trigger a definitive test like the fish sexual development test (FSDT) or the fish full life cycle test (FFLC), entailing ethical and economic problems. This study analysed 137 studies encompassing 35 chemicals with different modes of actions (MOAs). Variability is quantified for MOA endpoints vitellogenin (VTG) and secondary sex characteristics (SSCs) as well as for apical endpoints. Two MOA endpoints could indicate estrogenic, anti-estrogenic, androgenic, anti-androgenic and steroidogenesis activities. Great variability, however, has been observed for chemicals with anti-androgenic and steroidogenesis activities, suggesting that TG229/230 may not be sensitive enough to detect these types of chemicals and may produce false negatives. Changes in apical endpoints like fecundity are not limited to endocrine disrupting chemicals (EDCs). Non-EDCs could induce the similar effects on these apical endpoints. If elucidating MOA is needed, targeted in vitro MOA tests are suggested. Positive in vitro MOA results trigger a definitive test, which could be used for confirmation of the MOA in vivo and for deriving a no observed effect concentration (NOEC). Based on positive MOA results of TG229, a definitive test such as the FSDT or the FFLC is still needed, because the current TG229 has limitation on the derivation of a NOEC. An extended TG229 with more power to detect reproduction effects, as recently proposed in the OECD test guideline program, would improve the possibility to derive a NOEC and increase its usefulness in risk assessment.  相似文献   
135.
Birds have been comprehensively assessed on the International Union for Conservation of Nature (IUCN) Red List more times than any other taxonomic group. However, to date, generation lengths have not been systematically estimated to scale population trends when undertaking assessments, as required by the criteria of the IUCN Red List. We compiled information from major databases of published life-history and trait data for all birds and imputed missing life-history data as a function of species traits with generalized linear mixed models. Generation lengths were derived for all species, based on our modeled values of age at first breeding, maximum longevity, and annual adult survival. The resulting generation lengths varied from 1.42 to 27.87 years (median 2.99). Most species (61%) had generation lengths <3.33 years, meaning that the period of 3 generations—over which population declines are assessed under criterion A—was <10 years, which is the value used for IUCN Red List assessments of species with short generation times. For these species, our trait-informed estimates of generation length suggested that 10 years is a robust precautionary value for threat assessment. In other cases, however, for whole families, genera, or individual species, generation length had a substantial impact on their estimated extinction risk, resulting in higher extinction risk in long-lived species than in short-lived species. Although our approach effectively addressed data gaps, generation lengths for some species may have been underestimated due to a paucity of life-history data. Overall, our results will strengthen future extinction-risk assessments and augment key databases of avian life-history and trait data.  相似文献   
136.
At the global scale, biodiversity indicators are typically used to monitor general trends, but are rarely implemented with specific purpose or linked directly to decision making. Some indicators are better suited to predicting future change, others are more appropriate for evaluating past actions, but this is seldom made explicit. We developed a conceptual model for assigning biodiversity indicators to appropriate functions based on a common approach used in economics. Using the model, indicators can be classified as leading (indicators that change before the subject of interest, informing preventative actions), coincident (indicators that measure the subject of interest), or lagging (indicators that change after the subject of interest has changed and thus can be used to evaluate past actions). We classified indicators based on ecological theory on biodiversity response times and management objectives in 2 case studies: global species extinction and marine ecosystem collapse. For global species extinctions, indicators of abundance (e.g., the Living Planet Index or biodiversity intactness index) were most likely to respond first, as leading indicators that inform preventative action, while extinction indicators were expected to respond slowly, acting as lagging indicators flagging the need for evaluation. For marine ecosystem collapse, indicators of direct responses to fishing were expected to be leading, while those measuring ecosystem collapse could be lagging. Classification defines an active role for indicators within the policy cycle, creates an explicit link to preventative decision-making, and supports preventative action.  相似文献   
137.
本文分析了“三线一单”、产业园区规划环评在源头预防体系和环境管理中的定位及二者的空间拓扑关系。从技术方法、评价思路、评价尺度、评价重点和产出成果等方面对比解析了“三线一单”与产业园区规划环评的评价体系。从参考、落实、简化、细化(完善)、反馈5个环节分析了“三线一单”在产业园区规划环评中的应用路径,并以某高新区为例梳理分析了产业园区规划环评中衔接落实“三线一单”成果的方式。最后,从明确“三线一单”与规划环评在园区层面的定位和空间拓扑关系、完善二者衔接落实的技术方法体系、健全衔接落实的应用管理机制三个方面提出了推进“三线一单”在产业园区规划环评中应用的建议。  相似文献   
138.
利用抽样调查和收集资料得到的数据,对张掖市实施退耕还林(草)工程的影响从社会、经济和生态三个方面进行了评价。结果表明:张掖市退耕还林(草)社会可持续性的评价结果为“较好”;2002—2004年的退耕还林(草)工程在三年内给农户带来了17229.62万元的纯收入;通过三年的退耕还林(草),能增加植物碳量累积(NPP)170658.11t,NEP总量增加44544.94t。同时,还针对退耕还林(草)政策的完善提出建议:希望继续增加退耕还林(草)面积,在今后的退耕还林(草)工程中安排合理的还草面积,增加退耕还林(草)工程的配套费用。政府有关部门应切实解决退耕农户关心的问题。  相似文献   
139.
本文简述了我国危险废物环境管理实际工作中暴露出的原《国家危险废物名录》存在的主要问题,以及修订后的《国家危险废物名录》的修订原则、主要内容和涵盖的危险废物的来源等,并介绍了我国危险废物的认定框架。  相似文献   
140.
黄土丘陵区退耕还林还草对土壤细菌群落结构的影响   总被引:3,自引:0,他引:3  
为了探究黄土丘陵区退耕还林还草工程对土壤细菌群落的影响,本文以宁南山区玉米农地为对照,人工柠条地和天然草地为退耕还林还草的处理,利用Illumina二代高通量测序技术MiSeq对土壤细菌的16S rRNA V3~V4可变区进行测序,研究3种植被下土壤细菌的α多样性、物种组成和丰富度,并结合土壤理化性质探讨影响细菌群落结构的环境因素.3种土壤样品中共检测到细菌29门,76纲,135目,250科,375属,682种,主要的优势菌门为变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)、绿弯菌门(Chloroflexi)、芽单胞菌门(Gemmatimonadetes)、厚壁菌门(Firmicutes),主要的优势菌纲为α-变形菌纲(α-Proteobacteria)、放线菌纲(Actinobacteria)、酸杆菌纲(Acidobacteria)、β-变形菌纲(β-Proteobacteria)、嗜热油菌纲(Thermoleophilia)、芽单胞菌纲(Gemmatimonadetes)、杆菌纲(Bacilli)、δ-变形菌纲(δ-Proteobacteria).与耕地相比,林地的优势菌主要是变形菌门(Proteobacteria)和放线菌门(Actinobacteria),草地的是放线菌门(Actinobacteria)和酸杆菌门(Acidobacteria).柠条林地的土壤微生物多样性最高.通过RDA分析发现,影响本研究区域土壤细菌分布的最主要环境因子是全氮和有机质.研究表明通过退耕还林与还草工程明显地改善了土壤肥力和环境状况,改变了土壤细菌群落组成.  相似文献   
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