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1.
我国湿地评价研究综述   总被引:29,自引:5,他引:29  
杨波 《生态学杂志》2004,23(4):146-149
湿地评价研究已成为新世纪湿地科学前沿研究领域的热点问题。近年来 ,随着对湿地认识的不断深入 ,我国湿地评价研究内容不断丰富 ,研究水平提高幅度较大 ,研究方法由过去仅局限于湿地特征描述的定性评价 ,发展到湿地价值评价、湿地生态系统健康评价、湿地环境影响评价以及湿地生态风险评价等方面 ,3S技术和数学方法在湿地评价研究中也得到了较为广泛的应用。今后我国湿地评价研究应侧重于湿地评价理论、湿地评价指标体系和模型、湿地对比评价研究、退化湿地评价研究、湿地与全球气候变化以及新技术和新方法应用等方面  相似文献   

2.
生态系统健康评价方法初探   总被引:143,自引:13,他引:130  
生态系统是维持人类环境的最基本单元,生态系统功能主要体现在两个方面:一是生态服务功能(service);二是价值功能(goods)这两种功能是人类生态和发展的基础,生态系统健康是保证生态系统功能正常发挥的前提,结构和功能的完整性,具有抵抗干扰和恢复能力(resilience)、稳定和可持续性是生态系统健康的特征,生态系统健康评价需要基于生态系统的结构、功能过程来确定指标,包括生态系统的完整性,适应性和效率,生态系统健康评价主要有两种方法:一是指示物种评价,二是结构功能指标评价,结构功能指标评价包括单指标评价,复合指标评价和指标体系评价,指标体系评价中又包括自然指标体系评价,社会-经济-自然复合生态系统指标体系评价,本文针对生态系统健康的不同评价方法进行了对比研究,同时,针对不同的生态系统类型应选择其健康评价方法方面进行了简要的阐述。  相似文献   

3.
旱区流域水土环境质量的综合定量评价模型   总被引:3,自引:2,他引:3  
现有流域水土环境质量的评价方法大多根据评价区评价指标量化值与评价等级标准建立评价模型.评价区不同,评价模型也不相同,计算工作量较大.本文根据给定的水土环境质量评价等级标准,采用随机技术模拟生成足够数量的评价指标序列,应用人工神经网络模型,以评价指标生成序列和其所属的评价等级值建立一种通用的评价模型,其特点是不需要构造评价指标集和评价等级值间的函数关系和计算权重值,减少了建立模型的工作量.以西北地区水资源开发利用程度最高的石羊河流域进行实例研究,表明该模型可操作性强,可用于流域水土环境质量评价.  相似文献   

4.
The aim of this study was to contribute to knowledge about classroom assessment by identifying profiles of teachers’ assessment of their students’ understanding of mathematics. For carrying out this study we used data of a nationwide teacher survey (N = 960) in the Netherlands. The data were collected by an online questionnaire. Through exploratory factor analyses the underlying structure of what is measured by this questionnaire was uncovered as consisting of five factors: Goal centeredness of assessment, Authentic nature of assessment, Perceived usefulness of assessment, Diversity of assessment problem format, and Allocated importance of assessing skills and knowledge. By using a latent class analysis four different assessment profiles of teachers were identified: Enthusiastic assessors, Mainstream assessors, Non-enthusiastic assessors, and Alternative assessors. The findings suggest that teachers with particular assessment profiles have qualitatively different assessment practices. The paper concludes with discussing theoretical implications of these assessment profiles and indications these profiles can offer both for designing material for professional development in classroom assessment and for evaluating changes in teachers’ classroom assessment practice.  相似文献   

5.
生态安全评价研究述评   总被引:58,自引:6,他引:58  
生态安全评价是可持续发展研究的一个新领域,也是建立生态安全预警系统及进行环境管理的基础。首先介绍了与生态安全评价相关的几个概念:生态风险评价、生态系统健康评价、生态系统服务功能评价及生态承载力分析,进而对当前生态安全评价的指标体系进行了评述,并在此基础上总结了国内外生态安全评价的方法,包括数学模型法、生态模型法、景观生态学法及数字地面模型法;最后,提出在评价实践中存在的问题及今后发展的3个方向,静态的现状评价转向动态的预测和预警、与现代科学技术相结合、与基础理论相结合。  相似文献   

6.
课程考核是评价课程教与学效果的重要方式,在人才培养过程中发挥了指挥棒的作用。本文针对目前我国高等院校课程考核普遍存在的主要问题,以生物类专业基础课程“生物化学”为载体,通过文献研究、调查反馈和实践检验等方法,探索构建并实践“四化”形成性考核体系。其中考核主体的扩大化在主体范畴和考核载体两层面进行构建,考核过程的动态化在过程节点和反馈时效两个层面进行构建,考核内容的生态化在面向个体和群体两个维度进行构建,考核方式的多元化在考核形式、考核方法和计分方式三个层面进行构建。经过我校6个专业的6轮优化实践,对学生的学习和教师的教学均产生显著促进作用。  相似文献   

7.
Wetland assessment has been shown to be an important tool in understanding the condition and function of the world’s wetlands, and use of muli-tiered assessment strategy has been recommended. In order to evaluate the performance of each tier of a multi-tiered wetland assessment strategy, we sampled 255 seasonally-ponded wetlands in the Missouri Coteau, the most wetland dense ecoregion in the Prairie Pothole Region. We assessed the condition of each study wetland using four sampling methods and models (tiers) of increasing levels of effort and complexity: (1) a level 1 assessment using the geographic information system-based Landscape Wetland Condition Analysis Model (LWCAM); (2) a level 2 assessment using the North Dakota Rapid Assessment Method (NDRAM); (3) a level 3- assessment using the vegetative-based Floristic Quality Index (FQI) and (4) a level 3 assessment consisting of a Hydrogeomorphic (HGM) Model functional assessment. We compared assessment tiers to determine how similar the different levels of assessment ranked sites either by condition or function. Both the NDRAM and FQI assessments, though very different in wetland characteristics assessed, provided similar condition rankings as the more intensive level 3 HGM assessment (89 and 90% similar, respectively). Additionally, the FQI was 86% similar to the level 2 NDRAM, indicating that these two assessment methods have utility in assessing wetlands similar to a HGM assessment. Information from this study can be used as a tool for determining need specific, financial, and time appropriate wetland sampling methods.  相似文献   

8.
科室评估是通过对某个(类)科室多方面的分析,综合评价科室的价值与重要性,医院开展科室评估具有重要的理论和实际意义。文章探讨了公立医院科室评估的意义,构建了评估指标体系,并就科室评估的实施及应用进行了探索。  相似文献   

9.
流域生态风险评价研究进展   总被引:19,自引:8,他引:19  
流域生态风险评价是流域生态环境保护与管理的重要研究内容,与一般的区域生态风险评价相比,具有其独特的流域特征。在已有研究基础上,对流域生态风险评价进行了概念界定与特征分析,并按照风险源、生态受体、生态终点的分类标准对流域生态风险评价进行了类型划分,简要评述了流域生态风险评价的相关研究主题,并尝试构建反映流域时空尺度变化规律的生态风险评价概念模型。最后针对流域生态风险评价的研究现状,重点讨论了目前存在的不足及未来的研究趋向。  相似文献   

10.
城市生态风险评价研究进展   总被引:15,自引:2,他引:15  
随着城市化发展和城市人居环境的恶化,城市生态风险越来越受到关注,但尚缺乏有关城市生态风险评价的深入系统研究.本文依据城市生态学原理及生态风险评价框架从驱动力、风险源、风险受体与评价终点,以及生态风险综合评价方法等方面对城市生态风险评价研究进行综述.指出城市经济社会活动类型与程度是城市生态风险产生的主要驱动力;城市生态系统不同等级功能实体和城市整体是城市生态风险评价中的风险受体;城市生态风险评价终点包括城市生态系统结构、过程、功能要素,以及城市整体水平的性质和功能变化;耦合了社会经济需求的生态系统模型是城市生态风险评价方法的发展方向.未来城市生态风险评价研究应明确生态风险管理具体目标,确定综合性评价终点,建立多指标评价体系和综合评价方法.  相似文献   

11.
生态风险评价研究进展   总被引:62,自引:5,他引:57  
陈辉  刘劲松  曹宇  李双成  欧阳华 《生态学报》2006,26(5):1558-1566
20多年来,生态风险评价研究经历了从环境风险到生态风险到区域生态风险评价的发展历程,风险源由单一风险源扩展到多风险源,风险受体由单一受体发展到多受体,评价范围由局地扩展到区域景观水平.区域生态风险评价就是大尺度上研究复杂环境背景下包含多风险源、多风险受体的综合风险研究.目前,区域生态风险评价的理论框架已经搭建起来,统计方法多采用相对评价法.区域生态风险评价未来的发展方向为继续加强实验和野外调查,进一步减小不确定性,逐步解决尺度推移问题.区域生态风险评价必须与经济、社会、文化相结合,才能充分发挥它在管理决策中的作用.  相似文献   

12.
建立科学的绩效考核模式是医院提高员工积极性和创造性,提高医院运营效率和市场竞争力的重要手段。文章以医院绩效考核实践为基础,探讨如何建立以工作量核算为基础的绩效考核模式,包括绩效考核制定原则、核算体系、核算过程、分配形式、实践成效、工作体会等,为医院持续改进绩效考核工作提供参考。  相似文献   

13.

Background, aim and scope  

In the context of environmental life cycle assessment (LCA), life cycle impact assessment (LCIA) is one of the central issues with respect to modelling and methodological data collection. The thesis described in this paper focusses on the assessment of toxicity-related impacts, and on the collection of normalisation data. A view on the complementary roles of LCA toxicity assessment on the one hand and human and environmental risk assessment (HERA) on the other is presented, and the global, spatially differentiated LCA toxicity assessment model GLOBOX for the assessment of organics and metals is described. Normalisation factors for the year 2000 are calculated on a global as well as on a European level.  相似文献   

14.
外来植物的入侵机制及其生态风险评价   总被引:21,自引:1,他引:21  
马晔  沈珍瑶 《生态学杂志》2006,25(8):983-988
外来植物入侵已成为严重威胁生态系统健康发展的全球性问题,预防优于治理,对外来植物进行生态风险评价可有效地防御和降低入侵风险。本文基于生态风险评价理论,通过对外来植物入侵特性和过程的分析,探讨了外来植物入侵生态风险的评价方法。将评价程序分为风险源分析、风险受体评价、暴露与危害评价、风险综合评价和风险管理对策5部分,初步建立了风险源评价指标体系,以及度量生态损失和生态风险的指标和公式,进而得出外来植物入侵综合生态风险评价的方法。  相似文献   

15.
Ecological risk assessment will continue to increase in importance as a conceptual and methodological basis for evaluating environmental impacts as required by the National Environmental Policy Act. Understanding the historical strengths and limitations of more traditional environmental assessments performed in support of the NEPA can facilitate the effective incorporation of ecological risk assessment into the NEPA process. Such integration will also benefit from a knowledge of the historical and continuing development of the ecological risk assessment process, as well as from a recognition of the contri butions from modern quantitative ecology and ecosystem science. Adopting a risk-based approach can improve the NEPA process by providing a framework for consistent and comprehensive ecological assessment and by providing a conceptual and methodological basis for addressing the varied uncertainties attendant to environmental assessments. The primary concern in integrating ecological risk assessment into the NEPA process is that ecological risk assessment not merely become a new name for traditional environmental impact assessments. While the integration of ecological risk assessment into the NEPA process occurs, it is important to begin to outline the next transition in environmental assessment capabilities. Operationally linking ecological risk assessment methods with formal decision models appears as a worthwhile objective in beginning this transition.  相似文献   

16.
在可持续发展观的推动下,水域生态系统健康问题已引起各界的广泛重视.其中,河流、湖泊等水域的健康评价已开展很多,但对近海生态系统健康的研究还处于探讨阶段.本文在调研国内外大量文献的基础上,对近海生态系统健康的概念进行辨析,总结了近海生态系统健康状况评价的方法、指标筛选原则和研究思路等,并系统地列举了近海生态系统状况健康评价的一些相关量化指标.最后,针对目前近海生态系统健康研究领域存在的主要问题,提出了近海生态系统健康研究的发展方向,认为今后开展近海生态系统健康状况评价研究还需在概念及内涵剖析、评价指标筛选、评价尺度选取和评价方法集成等方面进一步加强.  相似文献   

17.
生态系统服务的物质量与价值量评价方法的比较分析   总被引:131,自引:11,他引:131  
对生态系统服务的物质量评价和价值量评价这两类评价方法进行比较,分析了这两类评价方法的优点和缺点,结果表明,采用物质量和价值量两种不同的方法对同一生态系统进行服务评价,往往会得出不同甚至相反的结论:对于不同的评价目的和不同的评价空间尺度,这两类评价方法的作用是有较大区别的,同时这两类评价方法在一定意义上又是相互促进和互为补充的。  相似文献   

18.
We give a mini-review of existing European risk assessment procedures and present a newly developed and tested risk assessment tool for invasive alien species (IAS) in Germany and Austria, the “German–Austrian Black List Information System” (GABLIS). Based on the analysis of existing European national risk assessment systems, we analyse and discuss: the assessment criteria used; which impacts of IAS (biodiversity, economy) have been considered; for which taxonomic groups has the assessment been designed and tested; how many and which list categories have been used; and, the status of the assessment, i.e. legally binding or advisory. We found that the application of risk assessment systems in Europe started belatedly, however recently a considerable number of assessment systems have been developed and tested. These systems encompass a wide range of purposes and approaches, and so far, no common standard on the aspects mentioned above has been emerged.GABLIS has been developed as a trans-national and taxonomically universal risk assessment system, which takes into account solely the detrimental effects of alien species on biodiversity. We describe which kinds of impacts are considered and how the thresholds have been scaled. We present the structure of the list categories, and we discuss the necessary underlying data for assessment, the assessment criteria and their scaling, and the assessment procedure. Five basic and six complementary criteria are used to assess the alien species’ impact. GABLIS includes three main list categories (White List, Grey List, and Black List).We discuss the practicability of GABLIS by presenting the assessment results of a model taxon (fish), and by presenting the assessment protocol for a vascular plant species. We discuss the necessary data quality for assessments, and the factors which account for differences in the assessments between both countries. We also report on experiences gained in assessments (e.g., average time necessary for assessments). The lessons learnt are discussed in the national and European political context of IAS management.Finally, we explore the strengths and caveats of this approach in the context of national policy on IAS in Germany and Austria and the ongoing European political initiatives. GABLIS is intended to serve as a comprehensive, flexible, but robust risk assessment tool for Central Europe. Being a trans-national risk assessment tool, GABLIS also tests principles, which might contribute valuable insights for a future overall strategy against IAS in Europe.  相似文献   

19.
In the European Union, Directive 92/32/EC and EC Council Regulation (EC) 793/93 require the risk assessment of industrial chemicals. In this framework, it is agreed to characterise the level of “risk” by means of the deterministic quotient of exposure and effects parameters. Decision makers require that the uncertainty in the risk assessment be accounted for as explicitly as possible. Therefore, this paper intends to show the advantages and possibilities of a probabilistic human health risk assessment of an industrial chemical, dibutylphthalate (DBP). The risk assessment is based on non-cancer endpoints assumed to have a threshold for toxicity. This example risk assessment shows that a probabilistic risk assessment in the EU framework covering both the exposure and the effects assessment is feasible with currently available techniques. It shows the possibility of comparing the various uncertainties involved in a typical risk assessment, including the uncertainty in the exposure estimate, the uncertainty in the effect parameter, and the uncertainty in assessment factors used in the extrapolation from experimental animals to sensitive human beings. The analysis done did not confirm the reasonable worst-case character of the deterministic EU-assessment of DBP. Sensitivity analysis revealed the extrapolation procedure in the human effects assessment to be the main source of uncertainty. Since the probabilistic approach allows determination of the range of possible outcomes and their likelihood, it better informs both risk assessors and risk managers.  相似文献   

20.
Current approaches to environmental risk assessment of genetically modified (GM) plants are modelled on chemical risk assessment methods, which have a strong focus on toxicity. There are additional types of harms posed by plants that have been extensively studied by weed scientists and incorporated into weed risk assessment methods. Weed risk assessment uses robust, validated methods that are widely applied to regulatory decision-making about potentially problematic plants. They are designed to encompass a broad variety of plant forms and traits in different environments, and can provide reliable conclusions even with limited data. The knowledge and experience that underpin weed risk assessment can be harnessed for environmental risk assessment of GM plants. A case study illustrates the application of the Australian post-border weed risk assessment approach to a representative GM plant. This approach is a valuable tool to identify potential risks from GM plants.  相似文献   

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