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1.
The objective of this study was to determine whether there was significant change in cognitive performance by prolonged duration of residence in polar environment. We examined volunteers (N = 23, scientific and logistic personnel) who spent fourteen months of continuous stay at ‘Maitri’ – The Indian research base in Antarctica (70 °45′S, 11 °44′E). Cognitive measures (tests of task acquisition, delayed recognition, attention and concentration, and digit symbol substitution) were obtained at the beginning (second month), the middle (seventh month) and the final (twelfth month) phases of prolonged residence in Antarctica. A repeated-measures MANOVA was conducted and the findings indicated a significant increase in percent accuracy in performance of task acquisition, delayed recognition and digit symbol tests that assessed recognition memory and learning. The test of attention and concentration that measured short-term memory for digits showed stable performance over a long-duration of residence in polar environment.  相似文献   

2.
This article describes three applications of the Universal Soil Loss Equation for further defining differences between natural environments in terms of their suitabilities for recreation use. Physical capacity limits based upon vulnerability to erosion and loss of soil productivity are discussed. Examples include: (a) applications to site planning and comparison of existing campsites; (b) use of the methodology for setting limits of acceptable change; and (c) characterization of third-order or larger watersheds that compare ecological land type interpretations with those based upon application of the equation.  相似文献   

3.
The struggle for healthy eating is a nascent social movement that represents active resistance to the hostile food environments created by multinational food and beverage corporations. Using a political economy approach and leveraging Winson's [2013. The industrial diet: the degradation of food and the struggle for healthy eating. Vancouver: UBC Press] concepts of dietary regimes and the industrial diet, this paper will examine the strengths and limitations of Brazil's new dietary guidelines and discuss its role as a precursor to a new dietary regime that incorporates social justice and sustainability.  相似文献   

4.
The objective of this study was to determine the concentrations of trace elements in sediment samples taken from impermeable urban areas of a city with predominantly agroindustrial development characteristics. For this, samples were taken every month from paved streets in the city of Toledo, Paraná State (PR), Brazil. Thus, trace element levels were obtained through analysis performed by optical emission spectrometry with inductively coupled plasma. Levels of total organic carbon were also obtained through the dry combustion method. When compared to local background levels, the trace element levels were shown to be enriched in the following percentage proportions: barium (Ba) (45.4%), copper (Cu) (48.6%), chromium (Cr) (37.2%), manganese (Mn) (81.6%), nickel (Ni) (0%), lead (Pb) (40%), zinc (Zn) (283.7%), magnesium (Mg) (34.3%), and sodium (Na) (250.2%), whereas the carbon (C) percentages were around 1%. The most significant enrichment factors occurred for Ba, Cr, Pb, Zn, Mg, and Na. The highest rates occurred in geoaccumulation where the sediments were enriched by zinc. According to the principal guidelines, the concentrations obtained for cadmium (Cd), Cr, Cu, Ni, and Zn can cause adverse environmental impacts.  相似文献   

5.

The release of carbon dioxide from the burning of fossil fuels is believed to be responsible for climate change. In the UK, road transport emits 22% of the total output of carbon dioxide. This study applies the ecological footprint to Merseyside to ascertain the global environmental impact of passenger transport (expressed in hectares). Results show that car travel has a footprint of 704 000 hectares, which is 87% of the total footprint. It is demonstrated in scenarios that Policy initiatives involving the Local Transport Plan will cause the footprint to increase. It is also shown that individual behaviour could be influenced when highlighting the impacts of different modes of transport along the same route. By using the ecological footprint in educational programmes, the effect can be shown of carbon emissions and land appropriation on the 'school run'; these issues could be promoted alongside others such as health, safety, congestion, global equity and fairness.  相似文献   

6.
At work, people may experience fatigue and a depletion of mental resources. The subsequent need for recovery is generally assessed employing subjective reports on evaluative statements. In this paper, we explore whether it is possible to assess employees’ recovery needs with a systematic inspection of behaviors. The idea is based on Campbell’s paradigm (Kaiser, Byrka, & Hartig, 2010), which holds that individuals will perform more, and more difficult behaviors to recover from fatigue when their need for recovery is higher.  相似文献   

7.
山地土壤—植物系统中汞污染问题的初步调查   总被引:2,自引:0,他引:2  
调查研究表明:在山地大气、水体质量较好的环境中,柑橘(含汞量)有超标问题,其土壤汞有超背景值现象;而蔬菜土壤则无此问题,其原因可能是由于多年生植物从大气和土壤中富积微量汞的时间较一年生植物长,以及土壤中砂粒结合汞粘粒结合汞具有更高的生物活性  相似文献   

8.
A number of state and federal agencies are presently attempting to develop management strategies for contaminated aquatic sediments. Until now, research and debate on sediment guidelines and regulations has focused almost exclusively on biological and chemical techniques for determining when sediments pose an environmental risk. Hydrologic factors must also be considered, however, if these biochemically based techniques for establishing sediment quality standards are to be feasible. Hydrologic issues that need to be addressed include how to define the boundaries of the aquatic environment, the scope of sediment regulations in ephemeral waters, regulations and sampling procedures in heterogeneous sediments, and timing of samples for monitoring and enforcement purposes  相似文献   

9.
The present paper examines the nature and dimensions of environmental transformation induced by canal irrigation in the arid region of India. The case study pertains to the Indira Gandhi Canal comand area in Rajasthan where the density and area of vegetation cover have increased due to afforestation, and the cultivated area has expanded due to irrigation. Consequently, there has been a perceptible improvement in the structure and fertility of sandy soils, but it would require a herculean effort on the part of the canal authority and local people to reduce soil erosion and siltation in the lower parts of stage I and the entire command area of stage II. Moreover, the water table has been rising rapidly throughout the command area of stage I. About half of the command area and adjoining Ghaggar basin in Ganganagar District will be facing the danger of waterlogging by the turn of the century. The incidence of irrigation-induced alkalization is higher in the lower parts of stage I. Soil alkalinity has appeared within five years of the introduction of irrigation in the interdunal basins and is manifested as a strong salt regime or calcareous pans near surface. This calls for immediate reclamation of the affected area and prevention of its expansion by altering the strategy of irrigation development, by changing cropping patterns, and by providing soil drainage.  相似文献   

10.
Restorative environments are environments that can help restore depleted attention resources or reduce emotional and psychophysiological stress. These effects have been demonstrated not only in real environments, but also in mediated (projected, broadcasted, etc.) environments. However, the importance of simulation qualities to restoration outcomes has not been systematically studied. The present experiment investigates the importance of immersion in a mediated environment in relation to restoration. Is a projected natural environment more restorative when one is more immersed in it, and hence feels more present in it? The hypothesis was that a more immersive projection would show stronger stress-reducing effects of a mediated restorative environment. After performing a stress-inducing task, participants watched a nature film on either a high or low immersive screen. Physiological measurements (heart period and skin conductance level) were taken throughout the experiment. In addition, we measured self-reported affect and presence using the ITC-Sense of Presence Questionnaire. Significant effects of the screen size manipulation appeared on physiological measures, but not on self-reported affect. The data showed an interaction between screen size and restorative phase on heart period and skin conductance level, indicating stronger restoration for the immersive screen condition over time. We therefore conclude that immersion enhances restorative potential of a mediated natural environment. Self-reported affect did correlate significantly with experienced presence, illustrating the relevance of this experiential counterpart of immersion, although a mediating effect of presence has not yet been established.  相似文献   

11.
通过采用相关年份有关城市方面的资料,从城市化水平,城市数量、体系和空间分布,城市社会经济发展状况,城市设施水平和城市经济效益5个方面,比较分析了我国三大地区城市发展现状,总结了我国三大地区的特征和城市发展差异,指出今后要积极缩小三大地区间的城市发展差距,推进区域经济的协调发展和可持续发展.  相似文献   

12.
通过对民族文化生态旅游的内涵分析,研究了民族文化生态旅游的开发模式、文化生态产业与旅游产业对接模式等内容,进一步提出我国西部民族文化生态旅游的开发对策。  相似文献   

13.
Jatropha has gained interest as a potential biodiesel feedstock. Nevertheless, its oil production decreases significantly in frost- and drought-prone regions. In this study, we characterized the flowering pattern of Jatropha in Botswana in the 2014/2015 season. Extensive springtime pruning synchronized Jatropha regrowth in summer and effectively stimulated growth after frost damage. Flowering started in February 2015 and peaked in April and May. Wide variations in flowering frequency were observed among different Jatropha accessions. Trees flowering in February and March produced fruit in May, but most trees only flowered in April and May and did not yield fruit because of cold snaps. These observations suggested that harvesting seed before wintertime is the key to improve Jatropha production in the Botswana climate. This study highlighted the importance of inducing early flowering by developing new agricultural managements. These may include frost cover and sun shades to prevent stress-induced damage, canopy control by pruning, optimization of fertilization practice, and/or introduction of superior Jatropha varieties.  相似文献   

14.
本文以山东省两个经济开发区区域环评为例,分析了各开发区在资源和环境方面的优劣势条件,论证了各开发区规划产业定位的合理性,探讨了开发区产业定位合理性评价的指标体系、调整原则、思路、方法,提出了各开发区产业定位的调整建议,并论证了调整后产业定位的合理性,促进了开发区的可持续发展。  相似文献   

15.
从环境污染应急预案编制、演练、实施以及应急保障等方面分析了水乡油田环境污染应急体系建立过程中需要注意的事项,并针对该企业环境污染应急体系建立过程中出现的问题,从应急预案编制、演练与实施以及应急保障方面提出了建议及初步解决措施。  相似文献   

16.
Land classification systems can be useful for assessing aquatic ecosystems if relationships among them exist. Because the character of an aquatic ecosystem depends to a large extent upon the character of the landscape it drains, spatial patterns in aquatic ecosystems should correspond to patterns in the landscape. To test this hypothesis, the US state of Ohio was divided into four aquatic ecoregions based on an analysis of spatial patterns in the combination of land-surface form, land use, potential natural vegetation, and soil parent material. During the period July–October 1983, fish assemblages were sampled in 46 streams that were representative of the ecoregions, and that had watersheds relatively undisturbed by human activities. Spatial patterns of the fish assemblages were examined relative to the ecoregions; distinct regional differences were identified. The assemblages differed most between the Huron/Erie Lake Plain region and the Western Allegheny Plateau region; assemblages in the Eastern Corn Belt Plains and the Erie/Ontario Lake Plain-Interior Plateau regions were intermediate. This pattern also reflects the gradient in landscape character as one moves from the northwest to the southeast of Ohio.  相似文献   

17.
网络团购已经逐渐发展成为一种新兴的电子商务模式,团购产品的覆盖范围也已非常广泛.揭示了民族地区旅行社电子商务发展与网络团购的内在相关性和作用机理,并探讨了适合民族地区旅行社电子商务发展的网络团购模式,提出了发展民族地区旅行社电子商务的思路与对策.  相似文献   

18.
Outdoor school environments are sites for play and physical activity for many children, and shortcomings within these environments are considered significant factors that contribute to children's inactive lifestyles and high levels of childhood obesity. This study explores the associations between the physical characteristics of schoolyards and the physical activity of third and fourth year students in five Turkish primary schools. Data were collected through multiple methods, including behavior mapping of student activities during recess, physical assessments of schoolyards, and interviews with students, teachers and administrations. The findings show similarities in the landscape features and physical qualities of schoolyards, particularly in the types of play and activities in which students engage. Results indicated that active students who walk to and from schools have lower body mass index (BMI) values than passive students, and students in schools with larger yards have lower BMI values. Most of the students prefer spacious and vegetated yards. A major concern is the crowdedness of the yards during recess that limit children's activity. Schoolyards with advanced landscape features are preferred more, and this in turn affects students’ positive satisfaction. Outdoor school environments have a correlation to health outcomes and should be designed to promote more activity. Improving the physical and landscape qualities of the public schoolyards should be the primary concern of the designers in order to increase awareness of natural environment and more important, increase the health of children.  相似文献   

19.
20.
This paper computes and analyses, for the first time, environmental efficiencies in waste generation of 116 European regions in NUTS 2 level in five European countries over the period of 2008–2010. For this reason, different data envelopment analysis (DEA) model formulations are used for modeling the pollutant in the form of waste generation as a regular output and as a regular input. In the latter case, we also use the notion of eco-efficiency. The empirical findings reveal environmental inefficiencies among the regions, indicating the lack of a uniform regional environmental policy among the European countries. This finding is observed not only for regions between different countries but also among the regions within countries, implying the need for implementation of unified appropriate municipal environmental policies in waste management.  相似文献   

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