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11.
区域生态系统适应性管理概念、理论框架及其应用研究 总被引:8,自引:0,他引:8
论述了生态系统适应性管理基本概念与生态系统适应循环,着重分析了生态系统恢复力范围、抗性、不稳定性与跨尺度影响。生态系统适应循环通常经历入侵、保持、破坏、调整四个阶段,前两个阶段的生态系统演替是可以预测的,而后两个阶段是复杂、难以预测的。文章提出了适应性区域生态系统管理的基本概念,并构建了其理论框架,并以三峡库区小江流域为例,对小江流域景观生态特征、区域生态胁迫进行了详细分析。在此基础上,提出要以水生生态安全为总目标,并围绕这一目标,进行流域各生态系统的恢复力辨识、生态系统适应性循环过程研究,从各系统恢复力属性特征出发,提出了具体的适应性管理方法与模式。 相似文献
12.
This paper discusses the REAP1 model and its application for the analysis of CO2 reduction and waste management policies for Japanese petrochemicals. The pros and cons of this modelling approach in comparison to other tools is elaborated. This is followed by a discussion of the model code and the modelling results. The results show that CO2 policies can have significant impacts on waste flows and waste policies can have significant CO2 benefits. As a consequence both effects must be considered in policy assessment. Pricing instruments are recommended instead of regulations because of the complex physical relations in the materials life cycle that extend beyond sector boundaries. A taxation approach is superior to a subsidy approach because rebound effects can be avoided. 相似文献
13.
Diazinon contamination of California's rivers has resulted in placing several rivers on the federal Clean Water Act § 303d list of impaired waterways. Impaired water body listing requiresthe development of Total Maximum Daily Loads (TMDL). Previous studies identified stormwater related diazinon pulses in California rivers. This study was conducted to monitor diazinonconcentrations in the Sacramento River watershed after rainfallevents, to ascertain whether pulses could be identified and, ifconcentrations of concern were observed, to estimate loadings anddetermine geographic origins of the insecticide. TMDL developmentrequires knowledge of contaminant sources, loadings, and geographic origins. Flow and diazinon concentrations peaked in the Sacramento River at Sacramento after the three largest stormsduring January and February 1994. Diazinon concentrations peakedconsequent to each of three storms. Diazinon concentrationsmeasured in the Sacramento River at Sacramento exceeded theCalifornia Department of Fish and Game acute and chroniccriteria for protection of aquatic life during January andFebruary for nine and nineteen days, respectively. Multipleexceedances were observed throughout the watershed. Diazinon loading and geographic origin differed with each of the three storms. The design of this study provides a useful template for others attempting to identify loadings and sources of contaminants in surface waters and to rectify aquatic ecosystemcontamination from various land use practices. 相似文献
14.
15.
Karin Andersson Merete Hgaas Eide Ulrika Lundqvist Berit Mattsson 《Journal of Cleaner Production》1998,6(3-4)
The feasibility of combining the concept of sustainability principles and the methodology of Life Cycle Assessment (LCA) is examined. The goal is to achieve an operational tool that incorporates sustainability in product development and strategic planning. While the method outlined has the structure of LCA, it emphasises aspects and parameters often omitted from traditional LCA. The analysis and results can be either qualitative or semi-quantitative. Although a qualitative analysis is less time consuming, it can still highlight the important issues. Qualitative information, which is easily lost in a quantitative analysis, can be emphasised. One of the conclusions is that the method is well suited for screening analysis. 相似文献
16.
对沈阳张士污灌区大气、水、土壤和生物各分室中Cd的库存量和各分室间Cd的循环通量进行了研究,建立了土壤-水稻系统中Cd流分室模型。该模型表明,Ⅱ闸和Ⅲ闸地区土壤分室中Cd的库存增量均为正值。可见,该污灌区近年来Cd污染程度由于污水灌溉仍然处于加剧的趋势。研究最后指出,该污灌区Cd的污染防治对策主要是减少污水灌溉量、进一步降低灌溉水中Cd的浓度和通过富Cd植物收获带走Cd.其中,以野生苋的收获带走Cd最有意义,它可使Ⅱ闸和Ⅲ闸地区Cd的下降速率分别依次达到29.49和22.81mg/(m ̄2·a)。 相似文献
17.
三界谷来地区主要出露中、新生代火山岩。进行 1/5万区域地质调查时,采用火山活动旋回-火山构造-火山地层-岩相、岩性-体化思路,按照同旋回火山机构或火山喷发区为单元,确定岩石地层单位和填图单元。火山岩划分为九种岩相类型,建立了两个岩相模式和一个三相一体成因模式。根据火山岩浆作用的旋回性及其产物与火山构造形迹时、空、成因一致性原理,将中、新生代火山岩浆作用分为四个火山活动旋回,圈定了相应的火山机构或火山喷发中心,建立了竹田头复活破火山演化模式。新生代玄武岩中发现二辉斜长麻粒岩等深源包体,为研究区域深部地质作用过程提供了证据。侵入岩按岩石谱系单元划分了七个岩石单元一个超单元,将侵入岩-潜火山岩-火山岩作为岩浆作用整体研究,为正确阐明岩浆作用及其演化规律奠定了基础。区域线型构造发育,与环形火山构造组合,形成火山岩区特有的线一环构造格局。中上元古界陈蔡群变质岩划分为上、下两个岩组,探讨了变质岩的原岩性质及其形成的大地构造环境。 相似文献
18.
Three mutually dependent elements are required for the application of life cycle assessment: methodology, data and software. Obviously, the design of software is determined by the methodology and the type of data available. Conversely, the development of software dictates the way in which data should be collected and recorded, and improves the theoretical framework, as it forces one to state the principles clearly and unambiguously. The influence of the development of software on both data and methodology is addressed and illustrated by examples, with reference to two key terms: transparency and explicitness. Three types of influence are distinguished: the design of a protocol, the formulation in terms of recipes, and the presentation of data. 相似文献
19.
Liu Quanyou 《环境科学学报(英文版)》1995,7(3):360-367
BiogeochemicalsulphurcycleinHaiheRiverBasinLiuQuanyou(ResearchCenterforEco-EnvironmentalSciences.ChineseAcademyofSceiences,Be... 相似文献
20.
This paper explores the practical application of life cycle assessment (LCA) to product system development. While life cycle assessment methods have been studied and demonstrated extensively over the last two decades, their application to product design and development has not been critically addressed. Many organizational and operational factors limit the integration of the three LCA components (inventory analysis, impact assessment and improvement assessment) with product development. Design of the product system can be considered a synthesis of individual decisions and choices made by the design team, which ultimately shape the system's environmental profile. The environmental goal of life cycle design is to minimize the aggregate environmental impacts associated with the product system. Appropriate environmental information must be supplied to decision makers throughout each stage of the development process to achieve this goal. LCA can serve as a source of this information, but informational requirements can vary as the design moves from its conceptual phase, where many design choices are possible, to its detailed design and implementation. Streamlined approaches and other tools, such as design checklists, are essential. The practical use of this tool in product development also depends on the nature and complexity of the product system (e.g. new vs. established), the product development cycle (time-to-market constraints), availability of technical and financial resources, and the design approach (integrated vs. serial). These factors will influence the role and scope of LCA in product development. Effective communication and evaluation of environmental information and the integration of this information with cost, performance, cultural and legal criteria will also be critical to the success of design initiatives based on the life cycle framework. An overview of several of these design initiatives will be presented. 相似文献