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1.
The cooling effect of greenspaces is an important ecosystem service, essential for mitigating the urban heat island (UHI) effect and thus increasing urban resilience to climate change. Techniques based on landscape planning to alleviate the increasing frequency of extreme climate are becoming more of a focus in urban ecology studies. In this paper, we proposed and defined the urban cooling island (UCI) extent, intensity, and efficiency, as well as the threshold value of efficiency (TVoE) introduced from the “law of diminishing marginal utility” for the first time. The radiative transfer equation has been compared with other algorithms and used to retrieve accurate land surface temperature (LST) in a subtropical city of China − Fuzhou. Two important and arguable factor − size and shape of greenspaces also been expressed and explored. The results indicate that: (1) larger-sized greenspaces produce a higher cooling effect. However, there exist a TVoE, which is in line with our hypothesis. The TVoE in Fuzhou is 4.55 ha. (2) The circles and squares greenspaces have a significant correlation with LST and also show the highest UCI intensity and efficiency. (3) 92% of the maximum extent of greenspaces are within the 30–180 m limit, and the mean UCI extent and intensity are 104 m and 1.78 °C. (4) The greenspaces connected with waterbodies intensified the UCI effects, whereas the grassland-based greenspace shows the weakest UCI effects. The methodology and results of this study could help urban planners to mitigate the UHI effects efficiently, and to employ the climate adaptive planning.  相似文献   

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Many studies have focused on the importance of immigrants participating in the public spaces of the cities where they have settled in order to become integrated. Our research, in contrast, demonstrates the importance of contextualizing participation within the framework of the power relationships that justify and give meaning to certain practices of discipline and control. We look at one concrete example in Seville (Spain): the regulation of the Latin American sports leagues of San Jeronimo. This case demonstrates the central role of public space in monitoring and controlling immigrants and in the dynamics of resistance they develop.  相似文献   

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The schizogenous intercellular spaces (i. e. those small spaces formed by cell walls coming apart) in the cortex of the roots of field-grown maize ( Zea mays L.) were studied in planed transverse faces of frozen tissue, very lightly etched and coated with Al. The spaces were mostly filled with either fluid or, in the drier roots, with a flaky deposit. This deposit may have been left behind when water was withdrawn, or may have been debris dislodged by the planing. Even in roots with mostly dry spaces, some wet, fluid-filled spaces remained. X-ray microanalysis of the wet spaces revealed that the fluid contained K (average concentration 230 m M , range 50–750 m M ) and Ca (average concentration 100 m M , range 15 to 550 m M ), and occasionally small amounts of S, P or Cl. No other balancing inorganic anions were detected. Concentrations in the wet intercellular spaces showed considerable variation between one space and the next, and were often quite different from those in the vacuoles of adjacent cells. However, overall the vacuoles of the cells surrounding the spaces showed mean concentrations, and distributions of concentrations, indistinguishable from those of the wet spaces. Analyses of the deposits in the dry spaces were less reliable because of their uneven surface, but the same ions in about the same amounts were found there. The contents of the spaces showed no correlation with either the time of collection of the roots, or with distance from the root tip. Nor was there any change in concentration of these ions in the spaces when the roots were grown for 19 h in distilled water mist. Experiments and evidence are presented suggesting that the observed distribution of ions is probably not an artefact. Pilot experiments showed similar distributions of extracellular ions in roots of barley, Sudan grass and soybean  相似文献   

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The present paper is the second part of our study in which we compare the results obtained in Szeged (Hungary) with those achieved through earlier outdoor thermal comfort projects based on simultaneous questionnaire surveys and on-site meteorological measurements. The main characteristics of the selected studies—conducted in Hungary, Sweden, Portugal, Canada, Taiwan and across Europe in the frame of project RUROS—are reviewed, emphasizing the common features and also the discrepancies in the applied methodology. We discuss their potential effects on the evolution and interpretation of the results concerning the subjective assessment of the thermal environment. Another aspect of the comparison focuses on the regional climatic differences naturally ensuing from the various locations, which left their marks on the results related to both physiological acclimatization and mental adaptation. The compared results of different studies include correlation coefficients expressing interrelationships between the different aspects of subjective estimations (thermal sensation, perceptions, preferences) and also between subjective assessments and the corresponding meteorological parameters. We compare neutral temperatures (expressed in physiological equivalent temperature, PET) which arose for Taiwan and Hungary, as well as thermal sensation zones for local inhabitants. Subjectively assessed temperature values of Sweden and Hungarians are analyzed according to the measured air temperature. According to our experiences the methodology should be standardized for the level of field surveys and also for the level of data processing in order to make the data collected in different locations comparable.  相似文献   

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During two investigation periods in transient seasons (14 weekdays in autumn 2009 and 15 weekdays in spring 2010) 967 visitors in two inner city squares of Szeged (Hungary) were asked about their estimation of their thermal environment. Interrelationships of subjective assessments—thermal sensation, perceptions and preferences for individual climate parameters—were analyzed, as well as their connections with the prevailing thermal conditions [air temperature, relative humidity, wind velocity, mean radiant temperature and physiologically equivalent temperature (PET)]. Thermal sensation showed strong positive relationships with air temperature and solar radiation perception, while wind velocity and air humidity perception had a negative (and weaker) impact. If a parameter was perceived to be low or weak, then it was usually desired to be higher or stronger. This negative correlation was weakest in the case of humidity. Of the basic meteorological parameters, Hungarians are most sensitive to variations in wind. Above PET?=?29°C, people usually prefer lower air temperature and less solar radiation. The temperature values perceived by the interviewees correlated stronger with PET, but their means were more similar to air temperature. It was also found that the mean thermal sensation of Hungarians in transient seasons depends on PET according to a quadratic function (R 2?=?0.912) and, consequently, the thermal comfort ranges of the locals differ from that usually adopted.  相似文献   

7.
As Myanmar undergoes political and societal transition, observers are asking questions about citizenship and ethnic identity. How does one think about citizenship and people's negotiations with law in political-legal regimes that do not subscribe to liberal democratic norms? This paper investigates how law marginalizes the Burmese Chinese minority in Myanmar and the nature of their legal participation. Since law asserts cultural power impacting the way people think and behave, we engage with the concept of legal consciousness to understand how perceptions of legal vulnerability shape political subjectivity ambivalently. The paper highlights the spatial strategies and everyday practices that the Burmese Chinese deploy to navigate oppressive laws, but signals that internal social divisions and geopolitical considerations deter collective action towards rights assertion. It argues that studying the multiple sites and scales through which law is engaged contributes towards recovering citizenship aspirations where engagement with power and authority are articulated differently from Western norms.  相似文献   

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