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1.
著: 《生物信息学》2019,26(2):32-42
介绍了位于洛哈市西南的提阿拉斯·科罗拉达斯(Tierras Coloradas)街区绿地和城市形象提升项目。以风景园林参与式设计方法为基础,该方法分5个阶段开展,从民众的主观批判精神开始,构成了参与行动的原动力。整个过程是在社区普及教学的进程中制定的,妇女是必须的参与者,共同找出邻里的问题和可能的解决办法。为此,普及教学是很有必要的,有助于未来社区项目的执行。重要的成果是,我们对部分城市街区进行了重新造林,改变了城市景观的形象,强化了社区体系, 促使社区在改善公共人行步道绿地方面开展合作。从专业的角度认为其主要效果是引导民众打破主观社区的非个人主观限制,为项目开展和参与打下基础。项目的整个社区干预过程是在高校、社区警察局、市政府等公共机构的支持下进行的,发挥着真正的协同作用,并齐心协力致力于该区块邻里间的自我发展,为未来与自然环境的友好关系奠定基础,这些都将影响社区的生活质量。  相似文献   

2.
This article, based on a case-study of Washington, DC, presents an historical-structuralist perspective on the social, political and economic forces that underlie contemporary patterns of US metropolitan inequality. Section one explores the unique history of the DC black population- the largest US urban concentration of African Americans until World War I. Section two discusses the ascendance of Washington, DC, as the international capital of the post World War II era. This period features the rapid expansion of white suburbia together with the growth and increasing concentration of African Americans in the urban core. Section three examines Washington, DC, as an exemplar of the US post-industrial metropolis. These distinguishing characteristics include the emerging 'multicultural majority' of the central city, widening urban/suburban socioeconomic 'divide', and profound shift in immigrant settlement patterns (from city to suburbia). The findings suggest that Washington, DC, may offer instructive insights into the future of multicultural relations in post-industrial US society.  相似文献   

3.
This paper introduces the concept of strategic ethnic performance (SEP), when members of one ethnic group present themselves as members of a phenotypically similar ethnic group for economic gain. I use ethnographic and interview data focused on Sub-Saharan African merchants involved in the Hip Hop fashion boutique business in urban Japan to show how SEP develops from four interconnected areas: the opportunity structure for ethnic entrepreneurs, the physical presentation of sellers, the arrangement of the selling venue, and feedback loops between the seller and the consumer. By utilizing SEP, ethnic entrepreneurs enhance the perceived authenticity of their goods and themselves. A thorough analysis of this process illuminates the interactional nature of ethnic authenticity as it is understood by consumers within urban areas.  相似文献   

4.
Freshwater habitats are important elements within urban green space and they are endangered by various types of human activity. With the aim to increase the knowledge about species biodiversity in urban ecosystems, we characterised the assemblages of aquatic insects in four permanent man-made ponds in Buenos Aires city (Argentina) during a 1-year period. We recorded 32 species with Sigara spp. (Hemiptera) as the most abundant. The removal of aquatic vegetation from the studied ponds may have affected both the establishment and permanence of the insect community. Swimmers were the dominant group in the studied sites, followed by burrowers and sprawlers, and only a few strictly climbers were collected. Therefore, all sampled ponds were dominated by collectors (principally gatherers), secondarily by predators and only few shredders were detected, which was much affected by the removal of macrophytes. Non-parametric abundance indexes estimated a number of species very close to the observed number in each site. Conversely, the incidence indexes estimated more species because there were many more taxa present only in one sample than those represented by few individual in a sample. Our data provides some insights on the community of man-made ponds that can improve the management of these aquatic urban habitats. Considering that macrophytes affect animal assemblages due to their role as physical structures that increase the complexity or heterogeneity of habitats, they should not be removed by authorities in order to promote biodiversity.  相似文献   

5.
城市生态系统是一个复杂的人工系统,城市经过快速掠夺式的发展已经造成绿地生态空间锐减,水体资源缺乏且污染严重,热岛效应突出和城市棕地面积大且污染严重等一系列生态问题。以资源枯竭型城市内大量存在的棕地为研究对象,认为城市棕地的修复需要生态智慧的引导,在建立生态智慧引导的城市棕地修复逻辑和框架的基础上,结合太原市棕地生态修复实践,建立从棕地安全性修复、棕地功能修复和棕地景观修复的综合修复框架,提出分期分类多元化再生,分类利用城市功能活化,去棕还绿抗污染植物配置棕地修复的生态智慧策略。  相似文献   

6.
Carly Ziter 《Oikos》2016,125(6):761-768
By 2050, up to 75% of people globally will live in cities. Despite the potential ramifications of this urbanization for ecosystem services (ES), and the importance of locally produced ES for the health and wellbeing of urban residents, syntheses addressing the underlying ecology of ES provision rarely include urban areas. Here, I conduct a quantitative review of urban ES studies in the ecological literature, synthesizing trends across the discipline. I also quantify the extent to which this work considers the organisms and ecosystem components responsible for ES provision using two approaches: assessment of biodiversity–ES relationships, and an adaptation of the service provider concept. The majority of urban ES studies were conducted in western, developed countries, and typically assessed a single service in a single city – largely ignoring ES synergies and tradeoffs, and cross‐city comparisons. While several different ES are studied in urban ecosystems, the field is dominated by weather and climate‐related regulating services, with assessments of cultural services particularly lacking. Most studies described a habitat type as the service provider; however, studies that considered the biodiversity–ES relationship were more likely to identify a specific functional group, community, or population as the key provider of an ES. The biodiversity–ES relationship itself was most frequently characterized as dependent on the composition of species, functional traits, or structures, rather than correlated with the magnitude of any specific biodiversity metric. While the study of ES in urban ecosystems is increasing, there exists considerable room for further research. Future studies would benefit by expanding the number and categories of ES assessed within and across cities, as well as broadening the geographical scope of urban ES research. Biodiversity–ES assessments in urban ecosystems would also benefit from an expansion of the biodiversity types considered, particularly regarding non‐species based approaches, and consideration of non‐native and invasive species. Synthesis Urban ecosystem services (ES) affect the health and wellbeing of over 3.5 billion people who live in cities. However, syntheses addressing ES provision rarely include urban areas. I conducted the first quantitative review focused explicitly on the ecology of urban ES, including the role of biodiversity in service provision. I found that studies typically measure only a single service in one city, precluding assessment of ES synergies, tradeoffs, and cross‐city comparisons. I also found that while most studies attribute ES provision to a habitat or land‐use type, studies that consider biodiversity‐ES relationships are more likely to recognize a specific functional group, community, or population as the key provider of an ES.  相似文献   

7.
The most prominent strand of moral thought in the African philosophical tradition is relational and cohesive, roughly demanding that we enter into community with each other. Familiar is the view that being a real person means sharing a way of life with others, perhaps even in their fate. What does such a communal ethic prescribe for the coronavirus pandemic? Might it forbid one from social distancing, at least away from intimates? Or would it entail that social distancing is wrong to some degree, although morally permissible on balance? Or could it mean that social distancing is not wrong to any degree and could, under certain circumstances, be the right way to commune? In this article, I defend the latter view. I argue that, given an independently attractive understanding of how to value communal relationship, distancing oneself from others when necessary to protect them from serious incapacitation or harm can come at no cost to right action. However, I also discuss cases in which social distancing would evince a lack of good character, despite being the right thing to do.  相似文献   

8.
Shaping sustainable, equitable African cities requires strengthened investigations into the cities’ current resource flows, infrastructure systems, and future resource requirements. The field of urban metabolism (UM) offers multiple forms of analysis with which to map, analyse, and visualize urban resource profiles. Challenges in assessing UM in African cities include data scarcity at the city level, difficulty in tracking informal flows, lack of standardized methods, and the open nature of cities. However, such analyses are needed at the local level, given that city practitioners cannot rely purely on urban planning traditions of the global North or the typically broad studies about urban Africa, for supporting strategies toward sustainable urban development. This article aims to draw together the concepts of sustainable development and UM and explore their application in the African context. Further, the article estimated resource profiles for 120 African cities, including consumption of biomass, fossil fuels, electricity, construction materials, and water, as well as emissions of carbon dioxide. These resource profiles serve as a baseline from which to begin assessing the current and future resource intensity of these cities. It also provides insights into the cities’ relative resource impact, future consumption trends, and potential options for sustainability interventions.  相似文献   

9.
Sustainable development efforts in urban areas often focus on understanding and managing factors that influence all aspects of health and wellbeing. Research has shown that public parks and green space provide a variety of physical, psychological, and social benefits to urban residents, but few studies have examined the influence of parks on comprehensive measures of subjective wellbeing at the city level. Using 2014 data from 44 U.S. cities, we evaluated the relationship between urban park quantity, quality, and accessibility and aggregate self-reported scores on the Gallup-Healthways Wellbeing Index (WBI), which considers five different domains of wellbeing (e.g., physical, community, social, financial, and purpose). In addition to park-related variables, our best-fitting OLS regression models selected using an information theory approach controlled for a variety of other typical geographic and socio-demographic correlates of wellbeing. Park quantity (measured as the percentage of city area covered by public parks) was among the strongest predictors of overall wellbeing, and the strength of this relationship appeared to be driven by parks’ contributions to physical and community wellbeing. Park quality (measured as per capita spending on parks) and accessibility (measured as the overall percentage of a city’s population within ½ mile of parks) were also positively associated with wellbeing, though these relationships were not significant. Results suggest that expansive park networks are linked to multiple aspects of health and wellbeing in cities and positively impact urban quality of life.  相似文献   

10.
Chen Y 《PloS one》2011,6(9):e24791
Zipf's law is one the most conspicuous empirical facts for cities, however, there is no convincing explanation for the scaling relation between rank and size and its scaling exponent. Using the idea from general fractals and scaling, I propose a dual competition hypothesis of city development to explain the value intervals and the special value, 1, of the power exponent. Zipf's law and Pareto's law can be mathematically transformed into one another, but represent different processes of urban evolution, respectively. Based on the Pareto distribution, a frequency correlation function can be constructed. By scaling analysis and multifractals spectrum, the parameter interval of Pareto exponent is derived as (0.5, 1]; Based on the Zipf distribution, a size correlation function can be built, and it is opposite to the first one. By the second correlation function and multifractals notion, the Pareto exponent interval is derived as [1, 2). Thus the process of urban evolution falls into two effects: one is the Pareto effect indicating city number increase (external complexity), and the other the Zipf effect indicating city size growth (internal complexity). Because of struggle of the two effects, the scaling exponent varies from 0.5 to 2; but if the two effects reach equilibrium with each other, the scaling exponent approaches 1. A series of mathematical experiments on hierarchical correlation are employed to verify the models and a conclusion can be drawn that if cities in a given region follow Zipf's law, the frequency and size correlations will follow the scaling law. This theory can be generalized to interpret the inverse power-law distributions in various fields of physical and social sciences.  相似文献   

11.
In the current debate on the future of bioethics in Africa, several authors have argued for a distinct communitarian African bioethics that can counter the dominancy of Western atomistic principlism in contemporary bioethics. In this article I examine this rather contentious argument and evaluate its validity and viability. Firstly, I trace the contextual origins of contemporary bioethics and highlight the rise and dominance of principlism. I particularly note that principlism was premised on a content‐thin notion of the common morality that is in need of enrichment. I also contend that bioethics is essentially two‐dimensional, being both conceptual and empirical, and indicate the lag in Africa with regard to conceptual bioethics. I then appeal for authentic engagement by 1) African health care professionals, 2) African health care training institutions, 3) Africa's bioethics development partners, and 4) African bioethicists and philosophers, towards addressing this critical lag. I underline the need to maintain the essential universality of bioethics as a discipline. I particularly argue against the pursuit of a distinct African bioethics, as it appears to be rooted in sterile African ethno‐philosophy. Rather, African bioethicists and philosophers would do well to elucidate the universalisability of insights from traditional African thought, for the benefit of bioethics as a whole. Thus we must engage beyond the sterility of a distinct African bioethics ‐ authentically reflecting on the essentially universal contemporary bioethical concerns ‐ to effectively articulate a viable trajectory for bioethics in Africa.  相似文献   

12.
According to development of the city, it has been revealed that demographic characteristics and living condition, as well as health status, have been differentiated among areas within it. On the causal relationships between urban growth and health, the present study shows no evidence, but a significant correlation between population density and demographic characteristics, and health, especially in maternal child health, have been observed in the same city (Takemoto et al., 1988). Considering the regionalization of characteristics in man and his environment within a city, public health activities based on the assessment of health needs in each community should be developed in urbanized society.  相似文献   

13.
The development of novel approaches that combine epidemiological and genomic data provides new opportunities to reveal the spatiotemporal dynamics of infectious diseases and determine the processes responsible for their spread and maintenance. Taking advantage of detailed epidemiological time series and viral sequence data from more than 20 years reported by the National Reference Centre for Rabies of Bangui, the capital city of Central African Republic, we used a combination of mathematical modeling and phylogenetic analysis to determine the spatiotemporal dynamics of rabies in domestic dogs as well as the frequency of extinction and introduction events in an African city. We show that although dog rabies virus (RABV) appears to be endemic in Bangui, its epidemiology is in fact shaped by the regular extinction of local chains of transmission coupled with the introduction of new lineages, generating successive waves of spread. Notably, the effective reproduction number during each wave was rarely above the critical value of 1, such that rabies is not self-sustaining in Bangui. In turn, this suggests that rabies at local geographic scales is driven by human-mediated dispersal of RABV among sparsely connected peri-urban and rural areas as opposed to dispersion in a relatively large homogenous urban dog population. This combined epidemiological and genomic approach enables development of a comprehensive framework for understanding disease persistence and informing control measures, indicating that control measures are probably best targeted towards areas neighbouring the city that appear as the source of frequent incursions seeding outbreaks in Bangui.  相似文献   

14.
北京城市公园常见乔木土壤真菌群落特征及影响因素   总被引:1,自引:0,他引:1  
于天赫  张乃莉  于爽  曲来叶 《生态学报》2021,41(5):1835-1845
快速城市化引起的城市环境污染问题日趋严重,由城市中心到城郊往往呈规律性递变趋势。北京城市公园作为城市绿地主体,不仅是城市居民重要的休闲游憩场所,也能在一定程度上反应环境污染,如土壤重金属污染的作用规律。以北京市这一典型大城市为研究区域,根据不同城市公园的建成时间、所处位置和距离市中心的远近选择六个公园作为研究样点,选取公园常见6种乔木下土壤,通过对土壤重金属含量、土壤理化性质以及土壤真菌群落测定和测序,旨在探讨城市公园植被下土壤真菌群落特征(多样性和群落结构组成)以及影响因素。研究结果表明:北京城市公园乔木下的土壤真菌群落多样性、群落组成以及优势类群受到土壤pH值、土壤养分和水分以及重金属铅的调控。其中公园土壤重金属铅含量增加会降低土壤真菌多样性、显著影响优势类群子囊真菌(占真菌群落73%)以及土壤真菌功能类群病原真菌群落组成。研究揭示了北京城市公园土壤真菌群落特征及调控因素,特别是重金属铅对土壤真菌群落的影响,这对提高城市公园科学管理和环境健康具有积极的应用价值。  相似文献   

15.
Pluzhnikov A  Di Rienzo A  Hudson RR 《Genetics》2002,161(3):1209-1218
Data from 10 unlinked autosomal noncoding regions, resequenced in 15 individuals from each of three populations, were used in a multilocus analysis to test models of human demography. Each of the 10 regions consisted of approximately 2500 bp. The multilocus analysis, based on summary statistics (average and variance of Tajima's D and Fu and Li's D*), was used to test a family of models with recent population expansion. The African sample (Hausa of Cameroon) is compatible with a constant population size model and a range of models with recent expansion. For this population sample, we estimated confidence sets that showed the limited range of parameter values compatible with growth. For an exponential growth rate as low as 1 x 10(-3)/generation, population growth is unlikely to have started prior to 50,000 years ago. For higher growth rates, the onset of growth must be more recent. On the basis of the average value of Tajima's D, our sample from an Italian population was found to be incompatible with a constant population size model or any simple expansion model. In the Chinese sample, the variance of Tajima's D was too large to be compatible with the constant population size model or any simple expansion model.  相似文献   

16.
Utopian groups, like other kinds of revitalization movements, work to create a new "cultural end-state." This implies, at the very least, a mild rejection of some of the present norms and institutions of the ambient society. To be allowed to continue its work, a utopian community must adopt to the demands of its cultural milieu, but at the same time it must do so in ways consonant with the group self-image. This essay reports on the adaptive tactics used by four Japanese utopian groups in dealing with present-day state institutions and with the public at large. It argues that in the study of utopian groups—and by extension revitalizations and revolutions—we must examine adaptive tactics as carefully as group goals if we hope to understand the fate of purposeful action in complex civilizations.  相似文献   

17.

Introduction

Accurate assessment of physical activity to identify current levels and changes within the population is dependent on the precision of the measurement tools. The aim of this study was to compare components of physical activity measured with an adapted version of the International Physical Activity Questionnaire (Hausa IPAQ-SF) and the accelerometer in a sample of Nigeria adults.

Methods

One hundred and forty-four participants (Mean age = 32.6±9.9 years, 40.3% women) in a cross-sectional study wore an accelerometer for seven consecutive days and completed the Hausa IPAQ-SF questionnaire on the eighth day. Total physical activity, time spent in moderate-to-vigorous activity (MVPA) and sedentary time assessed by Hausa IPAQ-SF and accelerometer were compared. The absolute and criterion- related validity of the Hausa IPAQ-SF was assessed by Bland-Altman analysis and Spearman Correlation Coefficients, respectively. Specificity and sensitivity were calculated to classify individuals according to the global standard guideline for sufficient physical activity.

Results

Compared with the accelerometer, higher time in MVPA and total physical activity were reported on the Hausa IPAQ-SF (p<0.001), while low to moderate correlations (Rs = 0.03–0.38) were found between the two methods. The 95% limits of agreement were wide between methods for total physical activity (−23019 to 20375 METmin.d−1) and sedentary time (−510 to 150 min.d−1). The sensitivity (76.2%) of Hausa IPAQ-SF to identify insufficiently active people was good, but its specificity (33.3%) to correctly classify sufficiently active people was low.

Conclusions

The Hausa IPAQ-SF overestimated components of physical activity among Nigerian adults, and demonstrated poor to moderate evidence of absolute and criterion validity. Further evaluation of IPAQ and other self-report physical activity instruments in other Africa populations could enhance accurate evaluation of physical activity data in the region countries.  相似文献   

18.
Acoustic signals play a fundamental role in avian territory defence and mate attraction. Several studies have now shown that spectral properties of bird song differ between urban and rural environments. Previously this has been attributed to competition for acoustic space as a result of low-frequency noise present in cities. However, the physical structure of urban areas may have a contributory effect. Here we investigate the sound degradation properties of woodland and city environments using both urban and rural great tit song. We show that although urban surroundings caused significantly less degradation to both songs, the transmission efficiency of rural song compared to urban song was significantly lower in the city. While differences between the two songs in woodland were generally minimal, some measures of the transmission efficiency of rural song were significantly lower than those of urban song, suggesting additional benefits to singing rural songs in this setting. In an attempt to create artificial urban song, we mimicked the increase in minimum frequency found several times previously in urban song. However, this did not replicate the same transmission properties as true urban song, suggesting changes in other song characteristics, such as temporal adjustments, are needed to further increase transmission of an avian signal in the city. We suggest that the structure of the acoustic environment, in addition to the background noise, plays an important role in signal adaptation.  相似文献   

19.
Wild bees along an urban gradient: winners and losers   总被引:2,自引:0,他引:2  
The variability of bee communities along an urban gradient has a potentially strong impact on pollinator-plant interactions. We investigated changes in bee species richness and community composition in the city centre and suburbs of Pozna??, Poland. During 2006?C2008 we recorded 2,495 individuals from 104 species. The most abundant species was Andrena haemmorhoa. Other abundant species were Bombus pascuorum, Andrena vaga, Andrena nitida, Bombus terrestris. Several species appeared to be more abundant in the city centre whereas others showed an opposite tendency. We have found that the urbanized landscape can act as a filter for the bee community since some specific ecological traits facilitate colonization of the city centre. Small-bodied species that start their activity later in the season and are not solitary preferred the city centre. However, bee species diversity and richness remained stable across the urban gradient indicating some advantages of being a city dwelling bee. We suggest that a city can be a very important habitat for a diverse bee fauna and that conservation of a wide range of habitats of different urbanization levels seems to be the most suitable strategy for conservation of bee diversity in cities.  相似文献   

20.
In the fifty years since Abel Wolman first published an estimate of U.S. urban metabolism, the field of urban metabolism has begun to thrive, with cities outside the United States being much of the focus. As cities attempt to meet local and international sustainability goals, it is time to revisit the metabolism of cities within the United States. Using existing empirical databases for material flows (the Freight Analysis Framework) and a published database on urban water flux, we provide a revised estimate of urban metabolism for the typical U.S. city. We estimate median values of metabolism for a city of one million people, considering water resources, food, fuel, and construction materials. Food consumption and waste production increased substantially to 3,800 metric tons per day and 4,900 metric tons per day, respectively. To facilitate a second generation of urban metabolism, we extend traditional analyses to include the embedded energy required to facilitate material consumption with important implications in determining sustainable urban metabolism. We estimate that a city of one million people requires nearly 4,000 gigajoules of primary energy per day to facilitate its metabolism. Our results show high heterogeneity of urban metabolism across the United States. As a result of the study, we conclude that there is a distinct need to promote policies at the regional or city scale that collect data for urban metabolism studies. Urban metabolism is an important educational and decision‐making tool that, with an increase in data availability, can provide important information for cities and their sustainability goals.  相似文献   

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