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151.
目前我国已存在的养老地产项目多数处于亏损状态,运营存在众多问题。基于现有问题,从养老地产的开发选址角度出发,对城市在养老地产开发初期的适宜性进行评估。建立包括人口因子、生活舒适度、居民消费能力、房地产市场成熟度和服务业发展程度五个维度的养老地产开发适宜性评价指标体系,并收集了2012—2016年河北省11个地级市的指标数据,运用基于组合赋权法的改进突变级数模型对11个城市的养老地产开发适宜性进行了评价。同时利用改进的障碍因子诊断模型对影响各城市养老地产开发适宜性的主要障碍因子进行诊断。通过分析得出主要  相似文献   
152.
To investigate the changes in the fish assemblage of the Sine Saloum estuary (Senegal) over a 10-year period, it was surveyed during a complete hydrological cycle (three principal hydro-climatic seasons) first in 1992 and then in 2002–2003. The sampling protocol for the two surveys was identical, using the same sampling technique, the same collection periods, and the same sampling stations.  相似文献   
153.
Implementing ecosystem based fisheries management (EBFM) will require a suite of ecological indices to track the state of an ecosystem, in addition to monitoring species-abundance for both economically important species, as well as species that are not targeted for harvest. However, EBFM implementation requires an examination of current methods and applications of ecological indices that are being used. This paper identifies four key uses for ecosystem indices in the context of EBFM and discusses the implications of each: (1) motivation for socio-political action, (2) information for individual users to modify their behavior, (3) implementation of decision rules for management evaluation, and (4) discovery of ecosystem functions to advance scientific knowledge. In a fisheries management context, ecological indicators will be linked to decision rules based on the definitions of both “ecosystem overfishing” and the current single-species definitions of overfishing. Two components of common ecological indicators are species weightings (i.e. catch or abundance data by species) and the species-specific ecological attributes (e.g. mortality rates, body size, trophic level). We discuss statistical issues that arise from estimating the parameters in ecological index calculations from both fishery-dependent and independent data and the potential biases introduced by using catch-per-unit-effort (CPUE) data, catch data, and abundance estimates. Given the range of biases that arise, often the best estimates of species weightings (abundances) are those derived from fish stock assessments. This implies that progress in EBFM may be best served by increasing the number of species for which single-species assessments are done and to expand the list of species to include species which may not be economically important. The policy framework exists to carry out EBFM; however, future works needs to focus on empirical management strategy simulations, as well as theoretical works to identify management criteria based on those indicators.  相似文献   
154.
Two unrelated data sources (quantitative secondary data and qualitative primary data) and mixed methodologies (statistical analysis and ethnography) are used to define the concept of, and develop indicators for, fishing dependence. Techniques for integrating differing data sources are developed. Comparisons of the qualitative rankings with the quantitative rankings were, overall, positive and statistically significant. The process used thus confirmed that the indicators were reliable measures for fishing dependence. In terms of external validity and triangulation, the process used was more rigorous than using ethnography “after-the-fact” to ground-truth the quantitative indicators.  相似文献   
155.
Integrative approaches that involve natural and social scientists are needed to manage fisheries, but these are difficult to achieve. The process of developing a prototype, knowledge-based, electronic decision support tool for the South African sardine Sardinops sagax fishery provided a platform for fostering collaboration and achieving active participation of many stakeholders. The aim of the decision support tool is to assist managers in evaluating how effectively an ecosystem approach to fisheries (EAF) has been implemented for this fishery. The collaborative process involved a series of meetings during which knowledge was elicited from fisheries scientists, social scientists, resource managers and fishing industry representatives. Conceptualisations of the different stakeholder perspectives were developed in terms of objectives and indicators following the hierarchical tree approach recommended by FAO. This paper describes the collaborative process. Hierarchies of objectives, indicators and data sets for the human dimension of an EAF in the South African sardine fishery are introduced. The value of a transdisciplinary approach towards an EAF in South Africa is discussed.  相似文献   
156.
Micromorphological evidences of climatic change in Yazd region, Iran   总被引:1,自引:0,他引:1  
The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past .time, particularly the paleoclimate. In this respect the micro- morphological properties showed to be a very good indicator. Therefore, for investigating of climate change in Ardakan-Yazd plain, Central Iran 9 pedons were digged and described. Yazd has an arid climate with less than 100 mm annual precipitation and more than 22℃ mean annual temperature (Aridic-hyper thermic soil moisture and temperature regions, respectively). Based on the morphological and physicochemical analysis Arglic, Calcic and Gypsic diagnostic horizons have been distinguished in these soils. Thin section studied showed that the illuviated form of clay includes, infillings on channel, coating on pendant, on nodules and on grains, at lower depths and also juxtaposed calcite needles on void argillan at upper part of the profiles. Mineralogical result showed fine clay in arglic horizon, too. Considering depth and forms of these pedofeatures, we concluded that, the observed illuviated clays at lower depth must be the result of the more humid climate of the past, where the carbonates have been removed completely as pendant, nodules or coating to considerable depth, following processes, clay has been dispersed and also trans located to these depths. In contrast to these features, the juxtaposed needle calcite at the shallower depth is probably the result of drier climate of today.  相似文献   
157.
The use of AMBI and M-AMBI in benthic quality assessments, within the European Water Framework Directive (WFD), has increased dramatically in recent years. M-AMBI is a multivariate tool, which incorporates AMBI, richness and Shannon diversity within the assessment. The response of this approach to different human pressures in coastal and estuarine waters has been investigated for the Basque Country (Northern Spain). In this contribution, several paradigmatic examples of these applications to different water bodies are presented. The time-series extend to samples collected between 1995 and 2007, showing the evolution of M-AMBI values under different pressures, i.e. urban and industrial discharges, dredging and disposal of sediments, and engineering works (such as land reclamation or marina construction), and, in addition, for illustrating the benthic quality recovery after positive actions have been undertaken, i.e. the removal of point-source discharges or water treatment programmes. In most cases, M-AMBI responds to these pressures as expected, with decreases in the ecological status immediately following the pressure. Conversely, when a pressure is removed, the recovery takes between 2 and 15 years, depending upon the intensity of the pressure and the characteristics of the water body. M-AMBI has been intercalibrated previously in coastal waters. After intercalibration in transitional waters, M-AMBI will be able to be used in the integrative quality assessment of European water bodies.  相似文献   
158.
Anthropogenic eutrophication affects the Mediterranean, Black, North and Baltic Seas to various extents. Responses to nutrient loading and methods of monitoring relevant indicators vary regionally, hindering interpretation of ecosystem state changes and preventing a straightforward pan-European assessment of eutrophication symptoms. Here we summarize responses to nutrient enrichment in Europe's seas, comparing existing time-series of selected pelagic (phytoplankton biomass and community composition, turbidity, N:P ratio) and benthic (macro flora and faunal communities, bottom oxygen condition) indicators based on their effectiveness in assessing eutrophication effects. Our results suggest that the Black Sea and Northern Adriatic appear to be recovering from eutrophication due to economic reorganization in the Black Sea catchment and nutrient abatement measures in the case of the Northern Adriatic. The Baltic is most strongly impacted by eutrophication due to its limited exchange and the prevalence of nutrient recycling. Eutrophication in the North Sea is primarily a coastal problem, but may be exacerbated by climatic changes. Indicator interpretation is strongly dependent on sea-specific knowledge of ecosystem characteristics, and no single indicator can be employed to adequately compare eutrophication state between European seas. Communicating eutrophication-related information to policy-makers could be facilitated through the use of consistent indicator selection and monitoring methodologies across European seas. This work is discussed in the context of the European Commission's recently published Marine Strategy Directive.  相似文献   
159.
Estuaries serve as nursery grounds for many marine fish species. However increasing human activities within estuaries and surrounding areas lead to significant habitat loss for the juveniles and decrease the quality of the remaining habitats. This study is based on the data of 470 beam trawls from surveys that were conducted in 13 French estuaries for the purpose of the European Water Framework Directive. It aimed at testing the effects of anthropogenic disturbances on the nursery function of estuaries. With a multispecific approach based on ecological guilds, two fish metrics, abundance and species richness of Marine Juvenile migrant fishes, were used as proxies for the estuarine nursery function. Indices of heavy metal and organic contaminations were used to estimate anthropogenic disturbances impacting these estuaries. Fish metrics were described with statistical models that took into account: (a) sampling protocol, (b) estuarine features and (c) contamination. The results of these models showed that the fish metrics highly depend on the sampling protocol, and especially type of gear, depth and salinity, which highlights the necessity of considering such metrics at the sampling (trawl haul) scale. Densities and species richness of Marine Juvenile fishes appeared to be strongly and negatively correlated to contamination indices. These results are consistent with the hypothesis that human disturbances impact the nursery function of estuaries. Finally, the densities of Marine Juvenile migrant species appeared as a potential robust and useful fish indicator for the assessment of the ecological status of estuaries within the Water Framework Directive.  相似文献   
160.
区域可持续发展的指标、标准和限制   总被引:1,自引:0,他引:1  
世界各国包括俄罗斯在内已经出版了大量关于可持续发展的理论研究方面的书籍。但总体而言,在不同结构层次(全球、国家、区域和地方)的可持续发展模型中,区域水平上的模型可能是最复杂和最基础的层次。本文在构建可持续发展模型的框架下,给出了一个区域经济、社会和生态发展的指标体系、标准和限制,并建立了一套评价区域自然资源潜力及其动态变化的方法。首先,对区域层次上达到可持续发展的条件和内容进行分析。其次,给出一个区域经济、社会和生态发展的框架。其中区域发展的经济质量是指其自身资源状况所带来的区域发展能力;区域发展的社会质量是指由区域的人口潜力和社会结构所带来的在一个长时期内稳定的区域人口以及由此提供的高标准生活质量的能力;区域发展的生态质量是指在一个长时期内区域保持其自然资源潜力和高质量环境的能力。区域可持续发展是在一个长时期内(10年)区域高质量的发展,在区域发展质量水平上进行可持续性和平衡性的评价是必要的,为此建立三者之间适当的比例关系。第三,为反映区域间发展的差异,对区域内的经济、社会等进行自然-经济区划以及对每个分区进行相应的指标的计算。这些绝对和相对的可持续发展比率反映了一定时期内实际的状态距离标准值的程度,刻画了区域发展的质量特征。如果这种比率发生变化,或者相对标准值发生动态改变,那么这些比率就可以评估发展的稳定性,以及同时反映了区域发展在质量上的提高或者降低。第四,区域自然资源潜力及其动态变化的评价。第一步是进行局部自然资源分区和把国土自然资源系统作为最复杂的评价对象进行整体考虑。然后对每一个自然资源系统进行动态平衡的计算(这种平衡反映了自然资源的动态和状态)。自然资源潜在的变化可以用实际的或者预测的数据进行计算。  相似文献   
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