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231.
70 beaches in Wales, UK, were investigated with regard to the quality of beach scenery using video panoramas. Beaches were
given a score from zero to 20 by a panel of 24 coastal managers (National Park and Heritage Coast Wardens, etc.) and 42 final
year Degree or Master of Science students specializing in environmental sciences. Mean scores of coastal managers ranged from
16.1 (Broadhaven, S. Pembrokeshire; 80%) to 3.8 (Prestatyn, North Wales; 19%), while scores of students ranged from 16.0 (Barafundle,
S. Pembrokeshire; 80%) to 6.1 (Trecco Bay, Porthcawl; 31%). Wave height, number of people present on the beach and position
on the final videotape did not have significant effects on mean scores generated by either group. With both groups a strong
preference was observed for undeveloped beaches over those where anthropogenic structures were prominent (p=0.00), but beach commercialization level had an independent effect only on scores from the student group (p=0.02). Cloud cover at time of filming had a significant effect (p=0.00) on scoring, so a correction was applied for final score calculation and ranking. The findings contribute to management
of coastal aesthetic resources by providing a quantitative evaluation scheme. It is proposed to use these scores for beach
scenery/aesthetic quality in a novel, comprehensive beach rating system. 相似文献
232.
Habitat loss and increasing landscape fragmentation are known to be key forces driving the ongoing loss of plant species diversity. While the combined effects of increasing isolation and decreasing population size have been studied intensively; it is less understood how plant population performance in heterogeneous landscapes is affected by changes in fragmentation alone. 相似文献
233.
城市景观河流夏季污染状况及营养水平动态分析--以天津市津河为例 总被引:4,自引:0,他引:4
以CODMn、氨氮、总氮、总磷和叶绿素a等为主要指标。对天津市一条典型的景观河流——津河进行了调查分析。结果表明,津河水质介于地表水环境标准(GB3838—2002)的Ⅳ和Ⅴ类之间,营养状态为重富营养。且在多个采样点出现蓝藻水华。水体中的各项指标的变化趋势为,CODMn与叶绿素a都是在7月达到最高,随后逐渐降低。总溶解性氮夏季变化曲线呈倒“S’形。7月最低。8月最高。河道上游总溶解性磷一直比较稳定,而下游在8月上旬急剧升高。藻类演替过程大致为粉末微囊藻-皮状席藻-多种蓝藻。与改造之初相比。水质状况有所改善。 相似文献
234.
235.
人类文明的发展,不断地在改变地球的生态环境,我们赖以生存的环境正在逐渐恶化,在城市中生活的人们远离了自然,生活环境已经不再健康,雾霾、水污染以及绿化的减少,都严重影响着人类自身的发展。在意识到环境对人类社会发展的重要性之后,人们开始重视城市环境的改造,引入原生态环境景观,希望获得人类与自然的和谐与平衡,在这样的背景下城市公园的概念受到了广泛的关注,城市公园的景观设计开始追求原生态,综合考虑了对原生态环境的保护和利用,不断完善城市公园的设计,发挥原有自然环境的作用,让人工设计与自然天成融为一体,打造城市中心的绿肺,改善城市生态环境,维护人类社会生产生活与自然环境的平衡,为人类建设更为宜居的生活环境。 相似文献
236.
Introduction: Fatigue is one of the most crucial factors that contribute to a decrease of the operating performance of aircraft pilots and car drivers and, as such, plays a dangerous role in transport safety. To reduce fatigue-related tragedies and to increase the quality of a healthy life, many studies have focused on exploring effective methods and psychophysiological indicators for detecting and monitoring fatigue. However, those fatigue indicators rose many discrepancies among simulator and field studies, due to the vague conceptualism of fatigue, per se, which hinders the development of fatigue monitoring devices. Method: This paper aims to give psychological insight of the existing non-invasive measures for driver and pilot fatigue by differentiating sleepiness and mental fatigue. Such a study helps to improve research results for a wide range of researchers whose interests lie in the development of in-vehicle fatigue detection devices. First, the nature of fatigue for drivers/pilots is elucidated regarding fatigue types and fatigue responses, which reshapes our understanding of the fatigue issue in the transport industry. Secondly, the widely used objective neurophysiological methods, including electroencephalography (EEG), electrooculography (EOG), and electrocardiography (ECG), physical movement-based methods, vehicle-based methods, fitness-for-duty test as well as subjective methods (self-rating scales) are introduced. On the one hand, considering the difference between mental fatigue and sleepiness effects, the links between the objective and subjective indicators and fatigue are thoroughly investigated and reviewed. On the other hand, to better determine fatigue occurrence, a new combination of measures is recommended, as a single measure is not sufficient to yield a convincing benchmark of fatigue. Finally, since video-based techniques of measuring eye metrics offer a promising and practical method for monitoring operator fatigue, the relationship between fatigue and these eye metrics, that include blink-based, pupil-based, and saccade-based features, are also discussed. To realize a pragmatic fatigue detector for operators in the future, this paper concludes with a discussion on the future directions in terms of methodology of conducting operator fatigue research and fatigue analysis by using eye-related parameters. 相似文献
237.
Evaluating Flow Metric‐Based Stream Classification Systems to Support the Determination of Ecological Flows in North Carolina
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Michele C. Eddy Jennifer Phelan Lauren Patterson Jessie Allen Sam Pearsall 《Journal of the American Water Resources Association》2017,53(1):30-41
Hydroecological classification systems are typically based on an assemblage of streamflow metrics and seek to divide streams into ecologically relevant classes. Assignment of streams to classes is suggested as an initial step in the process of establishing ecological flow standards. We used two distinct hydroecological river classification systems available within North Carolina to evaluate the ability of a hydrologic model to assign the same classes as those determined by observed streamflows and to assess the transferability of such systems to ungaged streams. Class assignments were examined by rate of overall matches, rate of class matches, spatial variability in matches, and time period used in class assignment. The findings of this study indicate assignments of stream class: (1) are inconsistent among different classification systems; (2) differ between observed and modeled data; and (3) are sensitive to the period of record within observed data. One clear source of inconsistency/sensitivity in class assignments lies with the use of threshold values for metrics that distinguish stream classes, such that even small changes in metric values can result in different class assignments. Because these two hydroecological classification systems are representative of other classification systems that rely on quantitative decision thresholds, it can be surmised that the use of such systems based on stream flow metrics is not a reliable approach for guiding ecological flow determinations. 相似文献
238.
Steve Cayzer Percy Griffiths Valentina Beghetto 《International Journal of Sustainable Engineering》2017,10(4-5):289-298
AbstractThis paper explores measurement of product performance with respect to circular economy (CE) principles. Potential indicators are assessed with special attention given to questions such as: the variables that should be measured; how these variables should be assessed; and in which format they should be presented. The resulting considerations are used to develop a prototype whose design is informed through feedback from CE experts. The prototype uses a points-based questionnaire which converges into a simple final result with minimum and maximum limits. The selected approach is critically appraised, and its utility for decision-making discussed. The prototype is tested against a product in the chemical processing industry. The strengths include: ease of use; simplicity; speed; and an effective metaphor for the diffusion of CE principles. The limitations include: the opaque and potentially misleading nature of a single metric; superficial engagement with decision-making; and the reliance on context-specific assumptions. Future developments could include refining the approach to encourage deeper reflection, and generalisation of the approach to different industry sectors or sustainability frameworks. 相似文献
239.
Muschal M 《Journal of environmental management》2006,80(3):266-278
A linear engineering project--i.e. a pipeline--has a potential long- and short-term impact on the environment and on the inhabitants therein. We must find better, less expensive, and less time-consuming ways to obtain information on the environment and on any modifications resulting from anthropic activity. We need scientifically sound, rapid and affordable assessment and monitoring methods. Construction companies, industries and the regulating government organisms lack the resources needed to conduct long-term basic studies of the environment. Thus there is a need to make the necessary adjustments and improvements in the environmental data considered useful for this development project. More effective and less costly methods are generally needed. We characterized the landscape of the study area, situated in the center and north-east of Argentina. Little is known of the ecology of this region and substantial research is required in order to develop sustainable uses and, at the same time, to develop methods for reducing impacts, both primary and secondary, resulting from anthropic activity in this area. Furthermore, we made an assessment of the environmental impact of the planned linear project, applying an ad hoc impact index, and we analyzed the different alternatives for a corridor, each one of these involving different sections of the territory. Among the alternative corridors considered, this study locates the most suitable ones in accordance with a selection criterion based on different environmental and conservation aspects. We selected the corridor that we considered to be the most compatible--i.e. with the least potential environmental impact--for the possible construction and operation of the linear project. This information, along with suitable measures for mitigating possible impacts, should be the basis of an environmental management plan for the design process and location of the project. We pointed out the objectivity and efficiency of this methodological approach, along with the possibility of integrating the information in order to allow for the application thereof in this type of study. 相似文献
240.
A Spatially Explicit Resource-Based Approach for Managing Stream Fishes in Riverscapes 总被引:1,自引:0,他引:1
The article describes a riverscape approach based on landscape ecology concepts, which aims at studying the multiscale relationships
between the spatial pattern of stream fish habitat patches and processes depending on fish movements. A review of the literature
shows that few operational methods are available to study this relationship due to multiple methodological and practical challenges
inherent to underwater environments. We illustrated the approach with literature data on a cyprinid species (Barbus barbus) and an actual riverscape of the Seine River, France. We represented the underwater environment of fishes for different discharges
using two-dimensional geographic information system-based maps of the resource habitat patches, defined according to activities
(feeding, resting, and spawning). To quantify spatial patterns at nested levels (resource habitat patch, daily activities
area, subpopulation area), we calculated their composition, configuration, complementation, and connectivity with multiple
spatial analysis methods: patch metrics, moving-window analysis, and least cost modeling. The proximity index allowed us to
evaluate habitat patches of relatively great value, depending on their spatial context, which contributes to the setting of
preservation policies. The methods presented to delimit potential daily activities areas and subpopulation areas showed the
potential gaps in the biological connectivity of the reach. These methods provided some space for action in restoration schemes. 相似文献