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1.
湖泊-流域生态系统管理的内容与方法   总被引:5,自引:2,他引:3  
刘永  郭怀成  黄凯  郁亚娟  戴永立  毛国柱 《生态学报》2007,27(12):5352-5360
在流域生态系统管理研究综述的基础上,对湖泊一流域生态系统管理的概念进行了界定,对水环境管理、综合流域管理与流域生态系统管理之间的差异进行了对比分析。确定了生态系统生态学、流域生态学、生态系统健康和流域方法为湖泊.流域生态系统管理的理论基础,生态系统方法和流域分析为其方法学基础。在上述分析的基础上,提出了湖泊.流域生态系统管理的6个主要步骤:研究范围界定、基础信息收集与基本生态学问题的分析和评价、管理目标设定、系统综合、生态系统综合评价、适应性管理;识别出湖泊-流域生态系统管理中的3个关键问题:①生态系统管理中的不确定性和障碍分析;②流域土地利用变化对湖泊水质和生态系统的影响;③流域生态子系统与社会子系统的关联。  相似文献   

2.

Purpose

Informal recycling is one of the most significant activities within waste management systems in low-income countries. The main aspect of a number of recently implemented waste management systems has been to organise the informal recycling sector. The implementation of formalisation is expected to eliminate social problems related to the informal sector, but this has not been precisely measured and evaluated. A lack of methodology to assess social impacts persists, as does the comparison of different formalisation approaches. The goal of this work is to develop a methodological procedure for assessing the contribution of formalised recycling systems in low-income countries in terms of social impacts, in comparison with informal systems.

Methods

Some existing social assessment approaches were evaluated by a review of literature. This investigation focuses on the development of the social life cycle assessment approach, the analysed social aspects, proposed indicators and characterisation models within this framework.

Results and discussion

This study proposes an approach for the social assessment of recycling systems based on formalisation approaches in low-income countries oriented towards the social life cycle assessment methodology (sLCA). The approach developed considers 3 social impact categories, 9 social subcategories and 26 semi-quantitative indicators for the assessment of the social impacts on formalised recyclers. It includes a characterisation procedure that takes into consideration the application of a score system and the calculation of average scores at both the indicator and subcategory levels.

Conclusions

This research shows that it would be feasible to apply a sLCA-based methodology to evaluate recycling systems based on formalisation of the informal sector. The impact categories and subcategories identified represent the social problems of informal recyclers. The 26 semi-quantitative indicators and the proposed characterisation approach attempt to measure the social impacts that currently are only qualitatively assumed. The applicability and validation of the indicators and characterisation procedure will be determined by further research. The methodology developed will be tested using data from three recycling systems in Peruvian cities.  相似文献   

3.
4.
Taxon‐specific DNA tests are applied to many ecological and management questions, increasingly using environmental DNA (eDNA). eDNA facilitates noninvasive ecological studies but introduces additional risks of bias and error. For effective application, PCR primers must be developed for each taxon and validated in each system. We outline a nine step framework for the development and validation of taxon‐specific primers for eDNA analysis in ecological studies, involving reference database construction, phylogenetic evaluation of the target gene, primer design, primer evaluation in silico, and laboratory evaluation of primer specificity, sensitivity and utility. Our framework makes possible a rigorous evaluation of likely sources of error. The first five steps can be conducted relatively rapidly and (where reference DNA sequences are available) require minimal laboratory resources, enabling assessment of primer suitability before investing in further work. Steps six to eight require more costly laboratory analyses but are essential to evaluate risks of false‐positive and false‐negative results, while step 9 relates to field implementation. As an example, we have developed and evaluated primers to specifically amplify part of the mitochondrial ND2 gene from Australian bandicoots. If adopted during the early stages of primer development, our framework will facilitate large‐scale implementation of well‐designed DNA tests to detect specific wildlife from eDNA samples. This will provide researchers and managers with an understanding of the strengths and limitations of their data and the conclusions that can be drawn from them.  相似文献   

5.
Environmental policy and in particular the European water legislation, in the framework of the EU Groundwater Directive, has started to consider groundwater not only as a resource but as a living ecosystem. A precondition for comprehensive groundwater protection is thus the assessment of the biological and ecological state. The assessment of ecosystems requires consideration of ecological criteria, which so far are not available for groundwater systems. In the framework of a national project, the German Federal Environment Agency (UBA) supports a consortium of scientists and stakeholders from water boards and regional environmental authorities to develop a first concept for an ecological assessment scheme for groundwater ecosystems. The attempts towards an integrative concept include the following steps: (i) selection of appropriate biological and ecological parameters, (ii) typology of groundwater ecosystems, (iii) derivation of a reference status (Leitbild) and natural background values for biological variables, (iv) identification of potential bioindicators and definition of threshold values, and (v) development of an assessment model. These proposed steps are discussed on the basis of a data set from two groundwater landscapes in Southern Germany. Investigations considered three different spatial units, i.e. the habitat unit at the local scale, and the aquifer type unit as well as the landscape unit at the regional scale. Fauna as well as bacterial communities could provide valuable ecological information on the ecosystems status. The paper reviews ‘state of the art’ knowledge and evaluates the near future perspectives for the development and implementation of groundwater ecosystems assessment programmes.  相似文献   

6.
Abstract

Target 2 of the European Biodiversity Strategy to 2020, whose aim was to maintain and restore ecosystems and their services, deals in practical terms with the mapping and assessment of ecosystems and their services, with the development of green infrastructure and with halting the loss of biodiversity at the EU, national, and subnational levels. The aim of this short communication was to show the activities currently being carried out in Italy that are related to this target, focusing on the contribution of vegetation science skills to the national implementation process. In particular, we outline noteworthy inputs in ecosystem mapping, in the assessment of ecosystem conservation status, in the individuation of priorities for the restoration of ecosystems, and in the settingup of an ecological framework to promote green infrastructure. An overview of the process outcomes and their relevance within the national and international contexts is also provided.  相似文献   

7.
Unbiased interpretation of noisy single molecular motor recordings remains a challenging task. To address this issue, we have developed robust algorithms based on hidden Markov models (HMMs) of motor proteins. The basic algorithm, called variable-stepsize HMM (VS-HMM), was introduced in the previous article. It improves on currently available Markov-model based techniques by allowing for arbitrary distributions of step sizes, and shows excellent convergence properties for the characterization of staircase motor timecourses in the presence of large measurement noise. In this article, we extend the VS-HMM framework for better performance with experimental data. The extended algorithm, variable-stepsize integrating-detector HMM (VSI-HMM) better models the data-acquisition process, and accounts for random baseline drifts. Further, as an extension, maximum a posteriori estimation is provided. When used as a blind step detector, the VSI-HMM outperforms conventional step detectors. The fidelity of the VSI-HMM is tested with simulations and is applied to in vitro myosin V data where a small 10 nm population of steps is identified. It is also applied to an in vivo recording of melanosome motion, where strong evidence is found for repeated, bidirectional steps smaller than 8 nm in size, implying that multiple motors simultaneously carry the cargo.  相似文献   

8.
The US EPA published guidelines for the application of ecological risk assessment (ERA) in the USA in 1998 (US EPA 1998). The process diagram derived by Murray and Claassen (1999) in an evaluation of the US EPA framework is discussed in the context of the South African National Water Act. The evaluation discusses the various steps involved in an ERA and how it can be applied in the implementation of the National Water Act. It is concluded that the application of ERA can make a significant contribution towards sustainable water resource management. Two requirements for this are the need for more demonstration projects and that capacity be developed in risk assessment and risk-based decision making.  相似文献   

9.
美国、加拿大环境和健康风险管理方法   总被引:2,自引:0,他引:2  
贺桂珍  吕永龙 《生态学报》2011,31(2):556-564
对目前美国和加拿大多个部门使用的风险评价与风险管理方法进行了全面回顾和综合分析,论述各种不同方法的特征,深入探讨各种管理方法的基础、利弊、使用经验,辨识环境、人类健康和职业健康风险综合方法中应该包含的要素,阐述风险管理目标的确定方法,以期为中国的环境风险管理提供经验。  相似文献   

10.
To contribute towards designing more cost-efficient, robust and flexible downstream processes for the manufacture of monoclonal antibodies (mAbs), a framework consisting of an evolutionary multiobjective optimization algorithm (EMOA) linked to a biomanufacturing process economics model is presented. The EMOA is tuned to discover sequences of chromatographic purification steps and column sizing strategies that provide the best trade-off with respect to multiple objectives including cost of goods per gram (COG/g), robustness in COG/g, and impurity removal capabilities. Additional complexities accounted for by the framework include uncertainties and constraints. The framework is validated on industrially relevant case studies varying in upstream and downstream processing train ratios, annual demands, and impurity loads. Results obtained by the framework are presented using a range of visualization tools, and indicate that the performance impact of uncertainty is a function of both the level of uncertainty and the objective being optimized, and that uncertainty can cause otherwise optimal processes to become suboptimal. The optimal purification processes discovered outperform the industrial standard with, e.g. savings in COG/g of up to 10%. Guidelines are provided for choosing an optimal purification process as a function of the objectives being optimized and impurity levels present.  相似文献   

11.
Background to the debate: The global burden of disease falls disproportionately upon the world''s low-income countries, which are often struggling with weak health systems. Both the public and private sector deliver health care in these countries, but the appropriate role for each of these sectors in health system strengthening remains controversial. This debate examines whether the private sector should step up its involvement in the health systems of low-income countries.  相似文献   

12.
S V Saveliev  M M Cox 《The EMBO journal》2001,20(12):3251-3261
DNA sequences (IES elements) eliminated from the developing macronucleus in the ciliate Tetrahymena thermophila are released as linear fragments, which have now been detected and isolated. A PCR-mediated examination of fragment end structures reveals three types of strand scission events, reflecting three steps in the deletion process. New evidence is provided for two steps proposed previously: an initiating double-stranded cleavage, and strand transfer to create a branched deletion intermediate. The fragment ends provide evidence for a previously uncharacterized third step: the branched DNA strand is cleaved at one of several defined sites located within 15-16 nucleotides of the IES boundary, liberating the deleted DNA in a linear form.  相似文献   

13.

Purpose

Since the implementation of the European directive (EC/2001/42) on strategic environmental assessment, an ex ante evaluation has become mandatory for plans and programs. This requirement could have significant consequences for the environment. Local authorities, who are in charge of land planning issues, must therefore conduct such assessments. However, they are faced with lack of uniform methodology. The aim of this paper is thus to propose a methodological framework for the required environmental assessment stages in land planning.

Methods

Life cycle assessment (LCA) has been identified as a promising tool to perform environmental assessment at a meso-level (i.e., territories). Yet, the standardized LCA framework has never been used for assessing the environmental impacts of a territory as such, which can be explained by the complexity that its application would involve. Four major methodological bottlenecks have been identified in this paper, i.e., (1) functional unit definition, (2) boundary selection, (3) data collecting, and (4) the refinement of the life cycle impact assessment phase in order to provide useful indicators for land planning. For each of these challenges, recommendations have been made to adapt the analytical framework of LCA.

Results and discussion

A revised framework is proposed to perform LCA of a territory. One of the major adaptations needed concerns the goal and scope definition phase. Henceforth, the association of a territory and the studied land planning scenario, defined by its geographical boundaries and its interactions with other territories, will be designated as the reference flow in LCA. Consequently, two kinds of indicators will be determined using this approach, i.e., (1) a vector of environmental impacts generated (conventional LCA) and (2) a vector of land use functions provided by the territory for different stakeholders (e.g., provision of work, recreation, culture, etc.). This revised framework has been applied to a theoretical case study in order to highlight its utility in land planning.

Conclusions

This work is a first step in the adaptation of the LCA framework to environmental assessment in land planning. We believe that this revised framework has the potential to provide relevant information in decision-making processes. Nonetheless, further work is still needed to broaden and deepen this approach (i.e., normalization of impacts and functions, coupled application with GIS, uncertainties, etc.).  相似文献   

14.
Life cycle assessment (LCA) is a methodology for assessing the environmental impacts associated with products throughout their lifecycle. Many impacts are accounted for within the LCA framework, but to date biodiversity impacts have received little attention. There are a number of existing direct and indirect measures of biodiversity within the ecological field, some of which have the potential to be developed into a useable method for LCA. However, our assessment is that considerable development would be required and their implementation for LCA is not likely in the foreseeable future. Here an alternative approach is proposed for rapidly incorporating biodiversity impacts into LCA. The approach relies on expert opinions through a series of questions which aim to encapsulate the main issues relating to biodiversity within a disturbance impact framework. While the technique is in its infancy we outline a foundation for the approach and identify the steps required to develop this method for implementation into LCA.  相似文献   

15.
This study summarises the biochemical and functional properties of a new generation plasma-derived, double virus inactivated von Willebrand Factor/Factor VIII (VWF/FVIII) concentrate, Wilate, targeted for the treatment of both von Willebrand disease (VWD) and haemophilia A. The manufacturing process comprises two chromatographic steps based on different performance principles, ensuring a high purity of the concentrate (mean specific activity in 15 consecutive production batches: 122 IU FVIII:C/mg total protein) and, thus, minimising the administered protein load to the patient (specification: < or = 15 mg total protein per 900 IU Wilate). The optimised solvent/detergent (S/D) treatment and prolonged terminal dry-heat (PermaHeat) treatment of the lyophilised product at a specified residual moisture (RM) provide two mechanistically independent, effective and robust virus inactivation procedures for enveloped viruses and one step for non-enveloped viruses. These process steps are aggressive enough to inactivate viruses efficiently, but yet gentle enough to maintain the structural integrity and function of the VWF and FVIII molecules, as proven by state-of-the-art assays covering the diverse features of importance. The VWF multimeric pattern is close to the one displayed by normal plasma, with a consistent content of more than 10 multimers, but a relatively lower portion of the very high multimers. The multimeric triplet structure is normal, underlining the gentle and effective manufacturing process, which does not require the addition of protein stabilisers at any step. The balanced activity ratio of VWF to FVIII is close to that of plasma from healthy subjects, rendering Wilate suitable also for the safe and effective treatment of patients with VWD.  相似文献   

16.
Purpose

Currently, social, environmental, and economic risks and chances of bioeconomy are becoming increasingly a subject of applied sustainability assessments. Based on life cycle assessment (LCA) methodology, life cycle sustainability assessment (LCSA) aims to combine or integrate social, environmental, and economic assessments. In order to contribute to the current early stage of LCSA development, this study seeks to identify a practical framework for integrated LCSA implementation.

Methods

We select possible indicators from existing suitable LCA and LCSA approaches as well as from the literature, and allocate them to a sustainability concept for holistic and integrated LCSA (HILCSA), based on the Sustainable Development Goals (SDGs). In order to conduct a practical implementation of HILCSA, we choose openLCA, because it offers the best current state and most future potential for application of LCSA. Therefore, not only the capabilities of the software and databases, but also the supported methods of life cycle impact assessments (LCIA) are evaluated regarding the requirements of the indicator set and goal and scope of future case studies.

Results and discussion

This study presents an overview of available indicators and LCIAs for bioeconomy sustainability assessments as well as their link to the SDGs. We provide a practical framework for HILCSA of regional bioeconomy, which includes an indicator set for regional (product and territorial) bioeconomy assessment, applicable with current software and databases, LCIA methods and methods of normalization, weighting, and aggregation. The implementation of HILCSA in openLCA allows an integrative LCSA by conducting all steps in a single framework with harmonized, aggregated, and coherent results. HILCSA is capable of a sustainability assessment in terms of planetary boundaries, provisioning system and societal needs, as well as communication of results to different stakeholders.

Conclusions

Our framework is capable of compensating some deficits of S-LCA, E-LCA, and economic assessments by integration, and shows main advantages compared to additive LCSA. HILCSA is capable of addressing 15 out of 17 SDGs. It addresses open questions and significant problems of LCSAs in terms of goal and scope, LCI, LCIA, and interpretation. Furthermore, HILCSA is the first of its kind actually applicable in an existing software environment. Regional bioeconomy sustainability assessment is bridging scales of global and regional effects and can inform stakeholders comprehensively on various impacts, hotspots, trade-offs, and synergies of regional bioeconomy. However, significant research needs in LCIAs, software, and indicator development remain.

  相似文献   

17.
This work contributes to the development of a dynamic life cycle assessment (DLCA) methodology by providing a methodological framework to link a dynamic system modeling method with a time‐dependent impact assessment method. This three‐step methodology starts by modeling systems where flows are described by temporal distributions. Then, a temporally differentiated life cycle inventory (TDLCI) is calculated to present the environmental exchanges through time. Finally, time‐dependent characterization factors are applied to the TDLCI to evaluate climate‐change impacts through time. The implementation of this new framework is illustrated by comparing systems producing domestic hot water (DHW) over an 80‐year period. Electricity is used to heat water in the first system, whereas the second system uses a combination of solar energy and gas to heat an equivalent amount of DHW at the same temperature. This comparison shows that using a different temporal precision (i.e., monthly vs. annual) to describe process flows can reverse conclusions regarding which case has the best environmental performance. Results also show that considering the timing of greenhouse gas (GHG) emissions reduces the absolute values of carbon footprint in the short‐term when compared with results from the static life cycle assessment. This pragmatic framework for the implementation of time in DLCA studies is proposed to help in the development of the methodology. It is not yet a fully operational scheme, and efforts are still required before DLCA can become state of practice.  相似文献   

18.

Background

This article describes the process used by the authors in developing an implementation intervention to assist VA substance use disorder clinics in adopting guideline-based practices for treating depression. This article is one in a Series of articles documenting implementation science frameworks and tools developed by the U.S. Department of Veterans Affairs (VA) Quality Enhancement Research Initiative (QUERI).

Methods

The process involves two steps: 1) diagnosis of site-specific implementation needs, barriers, and facilitators (i.e., formative evaluation); and 2) the use of multi-disciplinary teams of local staff, implementation experts, and clinical experts to interpret diagnostic data and develop site-specific interventions. In the current project, data were collected via observations of program activities and key informant interviews with clinic staff and patients. The assessment investigated a wide range of macro- and micro-level determinants of organizational and provider behavior.

Conclusion

The implementation development process described here is presented as an optional method (or series of steps) to consider when designing a small scale, multi-site implementation study. The process grew from an evidence-based quality improvement strategy developed for – and proven efficacious in – primary care settings. The authors are currently studying the efficacy of the process across a spectrum of specialty care treatment settings.  相似文献   

19.
In developing countries, participatory land-use planning is seen as a panacea to mitigate land-use conflicts and enhance land productivity. This assumption has not been thoroughly tested in wildlife corridors. Three villages were selected for this study. Several methods were used to provide indication of the performance of the plans against their stated objectives of mitigating conflicts and conserving wildlife corridors. Three hundred and fifty-eight households and eight park and extension workers were interviewed. In addition, focus group discussion with the nomadic Barabeig, field assessment and review of land-use plan/general management plan reports were carried out. Results reveal that land-use plans failed to achieve their set objectives. For example, 75% of the households held this view. Major causes of failure were insufficient participation by stakeholders in the planning process, lack of robust, transparent and accountable implementation strategies, inadequacy of qualified staff and lack of 'holistic approach' to the planning process. Taking these findings into account, an improved buffer zone land-use planning framework is suggested. For the framework to enhance both conservation and development and to enable policies and legislation, equitable benefit sharing and conservation education, initiation of compensation schemes for depredation caused by wild animals and intensification of patrols are required.  相似文献   

20.
This article reviews the fundamental techniques to quantify the physiological severity of (coronary) stenoses. Although a wide survey of different techniques and applications is provided, the focus of this review is on: 1) the assessment of the immediate effect of the stenoses on blood flow (i.e., the hemodynamic severity), and not on the assessment of the pathology of the vessel itself; 2) the flow reserve methods to defining the physiological severity of stenoses; and 3) the determination of blood flow and tissue perfusion by X-ray angiography (a short survey of other imaging modalities is provided as well). Although the practical implementation of the techniques is illustrated by applying them to coronary stenoses, most of the issues involved are of interest in other application areas (using other imaging modalities) as well. This review consists of four parts. The first part deals with the definition of stenoses severity; the second part with tracer kinetic theory necessary to determine flows by imaging; the third part focusses on (cardiac) imaging modalities, with an emphasis on X-ray angiography; and the last part illustrates the practical implementation of the techniques in cardiology.  相似文献   

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