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水利建设是我国的基础产业。在水资源持续发展目标的引导,基于水资源开发和利用水害防治和水环境保护过程的社会经济特点,提出了水利建设中国家与政府的三项职能;保障公共物品供给,提高社会经济效益;国有资产监督管理;水利建设综合管理与服务。  相似文献   
2.
Assessments of Wetland Functions: What They Are and What They Are Not   总被引:1,自引:0,他引:1  
/ Many methods have been developed over the last two decades to provide information about wetland functions, but there has been little discussion of the models and algorithms used. Methods for generating information about wetlands were analyzed to understand their similarities, differences, and the type of information provided. Methods can first be grouped by the type of information they provide-classifications, characterizations, ratings, assessments, and evaluations. Methods that characterize, rate, or assess wetlands may generate information using one of two conceptual approaches-logic and mechanistic. Most methods that generate a numeric assessment of performance or value of wetland functions rely on the mechanistic approach to constructing models. Rapid assessment methods based on mechanistic models, however, do not assess the rates or dynamics of ecological processes occurring in wetlands. Rather, they provide a clear and concise way of organizing our current, and often subjective, knowledge about wetland functions. This is one limitation of current methods that is often misunderstood both by wetland managers and the scientific community. The advantages and limitations of the assumptions and the computational elements inherent in these approaches are discussed to provide wetland managers and regulators a better understanding of the information they are using. KEY WORDS: Wetlands; Functions; Assessment; Models; Methods  相似文献   
3.
The hydrogeomorphic (HGM) approach for developing "rapid" wetland function assessment methods stipulates that the variables used are to be scaled based on data collected at sites judged to be the best at performing the wetland functions (reference standard sites). A critical step in the process is to choose the least altered wetlands in a hydrogeomorphic subclass to use as a reference standard against which other wetlands are compared. The basic assumption made in this approach is that wetlands judged to have had the least human impact have the highest level of sustainable performance for all functions. The levels at which functions are performed in these least altered wetlands are assumed to be "characteristic" for the subclass and "sustainable." Results from data collected in wetlands in the lowlands of western Washington suggest that the assumption may not be appropriate for this region. Teams developing methods for assessing wetland functions did not find that the least altered wetlands in a subclass had a range of performance levels that could be identified as "characteristic" or "sustainable." Forty-four wetlands in four hydrogeomorphic subclasses (two depressional subclasses and two riverine subclasses) were rated by teams of experts on the severity of their human alterations and on the level of performance of 15 wetland functions. An ordinal scale of 1-5 was used to quantify alterations in water regime, soils, vegetation, buffers, and contributing basin. Performance of functions was judged on an ordinal scale of 1-7. Relatively unaltered wetlands were judged to perform individual functions at levels that spanned all of the seven possible ratings in all four subclasses. The basic assumption of the HGM approach, that the least altered wetlands represent "characteristic" and "sustainable" levels of functioning that are different from those found in altered wetlands, was not confirmed. Although the intent of the HGM approach is to use level of functioning as a metric to assess the ecological integrity or "health" of the wetland ecosystem, the metric does not seem to work in western Washington for that purpose.  相似文献   
4.
用矿井通风仿真系统(MVSS)确定通风系统优化改造方案   总被引:16,自引:1,他引:16  
论述了矿井通风仿真系统 (MVSS)的功能 ,用MVSS仿真模拟增加或减少风路对周围其他风路的影响 ,仿真模拟拆除或增加机站对周围通风系统的影响 ,并以金川矿井 115 0水平为例 ,阐明了用MVSS确定通风系统优化改造方案的方法 ,对通风系统现状分析、通风网络优化、通风系统的设计提供了科学的依据和实用方法。  相似文献   
5.
论美国的跨区域大气环境监管对我国的借鉴   总被引:1,自引:0,他引:1  
空气是流动的,以行政区域为边界的大气环境的管理是不合理的,所以要建设跨区域的大气环境监管体系。鉴于建设跨区域大气环境监管的重要性,为了更好的建设这一体系,本文以州内和州间两个层次上的大气环境监管情况为例研究了美国国内的跨区域大气环境监管体系,在此基础上,结合我国目前的跨区域大气环境监管体系,从机构设置、职能职责、运作方式等方面分析了两国不同国情情况下的环境监管体系,阐述了我国目前存在的不足和有待进一步完善的方面。最终从机构设置、职能职权、人员素质、审查机构等方面提出了改善我国当前跨区域大气环境监管机制的几点建议。  相似文献   
6.
城市道路交通安全智能化管理系统研究   总被引:6,自引:8,他引:6  
应用现代交通安全管理理念以及先进的信息技术、控制技术、网络信息传输技术 ,建立城市道路交通安全智能化管理系统 ,是提高交通安全管理的重要手段。笔者提出道路交通安全智能化管理系统由安全管理层、基础设施层、共用信息层、增值服务层组成 ;研究了城市道路交通安全智能化管理系统的框架和总体配置 ;认为该系统应具有的 6个基本功能及工作流程  相似文献   
7.
Roman Seidl 《Ambio》2015,44(8):750-765
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8.
Regulators protecting riparian areas need to understand the integrity, health, beneficial uses, functions, and values of this resource. Up to now most methods providing information about riparian areas are based on analyzing condition or integrity. These methods, however, provide little information about functions and values. Different methods are needed that specifically address this aspect of riparian areas. In addition to information on functions and values, regulators have very specific needs that include: an analysis at the site scale, low cost, usability, and inclusion of policy interpretations. To meet these needs a rapid method has been developed that uses a multi-criteria decision matrix to categorize riparian areas in Washington State, USA. Indicators are used to identify the potential of the site to provide a function, the potential of the landscape to support the function, and the value the function provides to society. To meet legal needs fixed boundaries for assessment units are established based on geomorphology, the distance from “Ordinary High Water Mark” and different categories of land uses. Assessment units are first classified based on ecoregions, geomorphic characteristics, and land uses. This simplifies the data that need to be collected at a site, but it requires developing and calibrating a separate model for each “class.” The approach to developing methods is adaptable to other locations as its basic structure is not dependent on local conditions.  相似文献   
9.
Genetic mechanisms determining habitat selection and specialization of individuals within species have been hypothesized, but not tested at the appropriate individual level in nature. In this work, we analyzed habitat selection for 139 GPS-collared caribou belonging to 3 declining ecotypes sampled throughout Northwestern Canada. We used Resource Selection Functions comparing resources at used and available locations. We found that the 3 caribou ecotypes differed in their use of habitat suggesting specialization. On expected grounds, we also found differences in habitat selection between summer and winter, but also, originally, among the individuals within an ecotype. We next obtained Single Nucleotide Polymorphisms (SNPs) for the same caribou individuals, we detected those associated to habitat selection, and then identified genes linked to these SNPs. These genes had functions related in other organisms to habitat and dietary specializations, and climatic adaptations. We therefore suggest that individual variation in habitat selection was based on genotypic variation in the SNPs of individual caribou, indicating that genetic forces underlie habitat and diet selection in the species. We also suggest that the associations between habitat and genes that we detected may lead to lack of resilience in the species, thus contributing to caribou endangerment. Our work emphasizes that similar mechanisms may exist for other specialized, endangered species.  相似文献   
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