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11.
生态位理论及其在生态经济规划中的应用   总被引:23,自引:0,他引:23  
生态经济规划是生态经济建设的重要组成部分。本文根据区域经济发展与资源环境条件的关系,初步探讨了生态位理论在生态经济规划中的应用。  相似文献   
12.
The Hannah-Kay [1977] generalized concentration index contains the well-known Herfindahl [1950]-Hirschman [1945] and the entropy indices as particular cases. In this papaer we show that the Hannah-Kay class can be regarded as a particular member of a generalized family of indices, which we refer to as self-weighted quasilinear means. We then show that among all self-weighted quasilinear means the Hannah-Kay family is the only class of concentration indices which satisfies the replication principle, a requirement which states that an m-fold replication of the industry, firm by firm, will multiply the concentration index by the factor 1/m.The refereeing process of this paper was handled through N.R. Adam.We are grateful to two anonymous referees for their suggestions.  相似文献   
13.
本文在正确理解农村全面小康社会内涵和借鉴吸收前人研究成果的基础上,重新构建了一套农村全面小康社会建设监测指标体系和监测方法,  相似文献   
14.
活动断裂附近地质条件复杂,在其附近进行新城镇选址时必须明确活动断裂对场地和建筑可能带来的不利影响。以金沙江乌东德水电站库区移民集镇选址为例,依照规范要求,综合地质调查、物探、勘探等手段,查明了元谋活动断裂的分布及特征;对其可能产生的震害类型及程度进行了分析;结合地质条件对规划场地工程建设的适宜性进行了分区;明确了活动断裂对场地和建筑物的影响,为合理设防、规避震害奠定了基础。可为类似新建城镇选址规划提供借鉴。   相似文献   
15.
淤泥质河口是填海建港主要地区,体现出明显城市化形态特征,却未在城市形态学领域引发实质性研究,导致填海规划缺乏指导。本文选择20个研究对象,以适宜分辨率Goo对eEanh影像为数据源,利用形态绘制方法,依据基础形态指数稳定域,得出河口区适宜研究幅度和精度,并利用填海方式破碎度和潮间带特征指数分析河口形态与生态特征。结果显示,多数案例河口因填海使潮间带衰退严重;亚洲填海河口在以潮间带相关指数为生态评价要素的前提下,反映出较差形态稳定性和生态状况;同等填海规模下,单斑块填海比多斑块分散填海对潮间带侵占破坏更大。  相似文献   
16.
The diversity of fish species found in warmwater stream systems provides a perplexing challenge when selecting species for assessment of instream flow needs from physical habitat analyses. In this paper we examined the feasibility of developing habitat suitability criteria (HSC) for the entire fish community of a warmwater stream using habitat guilds. Each species was placed a priori into a guild structure and habitat data were collected for depth, velocity, Froude number, distance to cover, embeddedness and dominant and subdominant substrate. Correct guild classification was tested with linear discriminant analysis for each species. Correct classification based on habitat‐use data was highest for riffle and pool‐cover guilds, whereas the fast‐generalist and pool‐run classes, the broader niche guilds, were more frequently misclassified. Variables most important for discriminating guilds were Froude number, velocity and depth in that order. Nonparametric tolerance limits were used to develop guild suitability criteria for continuous variables and the Strauss linear index was used for categorical variables. We recommend the use of a wide array of variables to establish more accurate habitat analysis. Additionally, guild HSC can be developed with similar effort to that needed to develop HSC for a small number of individual species. Results indicate that a habitat guild structure can be successfully transferred to another river basin and that habitats for a diverse fish assemblage can be adequately described by a small number of habitat guilds. This approach represents an alternative for incorporating entire fish assemblages into habitat analyses of warmwater stream systems. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
17.
Much effort has gone into the recognition of the human right to water. Without doubt, this milestone influences governance and decision making processes at many scales so it is essential now to shift the discussion from the legal and conceptual framework to practice. Along this line, the article proposes a methodology for monitoring access to water in rural areas using the framework of this human right. The practicality of the approach is demonstrated by a case study carried out in Nicaragua. Different criteria of the right to water were included in surveys and structured interviews that were conducted in rural households and water committees, respectively. A discussion analyzes the advantages and challenges of using this framework. Finally, the approach provides elements for policy making that can be used by different stakeholders in the development and human rights sectors.  相似文献   
18.
This paper develops constant-quality price indices for three categories of real estate-apartment buildings, vacant land, and condominiums—for the city of Geneva, Switzerland. We use both the hedonic and repeat sales models to estimate the price level and, in turn, the rate of price change. The general pattern of each series suggests that real estate prices in Geneva were fairly stable throughout the 1970s, increased sharply during the 1980s, but gave back some of these gains in the early 1990s. Interestingly, the sharp rise in prices in the second half of the 1980s is very similar to that found in some regions of the United States. We also consider the problem, implicit in the repeat sales method, of revisions in previously estimated price indices as additional data become available in later years.  相似文献   
19.
从“语言分析方法”角度研究后期维特根斯坦哲学。“日常语言分析”既是分析哲学的重要特征,也是维特根斯坦后期哲学的重要特征。维氏哲学的日常语言分析方法包括“合适性标准”及日常语言分析方法(步骤)二大基本内容。  相似文献   
20.
We construct and compare three distinct measures of household asset wealth that complement traditional income‐ or expenditure‐based measures of socioeconomic status. We apply these measures to longitudinal household survey data from China and demonstrate that household asset wealth has been increasing over time, a theme consistent with many previous studies on the process of development in China. Unlike other studies that have shown rising income inequality over time, however, we show that asset wealth inequality has actually been declining in recent years, indicating widespread participation in the benefits of economic reforms. Furthermore, the evolution in the cumulative distribution of household welfare is such that social welfare has been increasing with the passage of time, despite rising inequality in the early years of the survey.  相似文献   
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