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331.
The positive effect of natural compared to urban environment on human restoration and well-being has been proved in various studies. To go one step further in analyzing the influence of physical environments, we question if this positive effect is consistent in different natural conditions namely wild and tended urban forests. In an experimental field setting, participants were randomly assigned to either a walk through wild or tended forests for 30 min. Multidimensional scales in a pre-post-treatment-setting measured well-being. Results indicate a stronger change in “positive affect” and “negative affect” in the tended forest condition. Well-being factors “activation” and “arousal” changed after solitary walks, too. However, there were no differences between the treatment conditions, indicating a stronger influence of physical activity than the forest condition wild and tended on these well-being factors. Perceived attractiveness of the natural area did not effect the change in well-being, thus questioning the close relation between perceived attractiveness and the effect on well-being suggested in prior research. Furthermore, more and less fatigued persons did not profit differently concerning well-being changes. The results give important advice to design natural areas serving restoration and public health, especially for people living in urban environments.  相似文献   
332.
Twelve sediment cores were collected in July 2007 in open waters of western Bohai Bay, the Port of Tianjin, and the adjacent estuaries of the Haihe and Yongding Rivers. While overall concentrations of trace metals at incremental depths in these cores met the Marine Sediment Quality (GB18668-2002) criteria of China, the magnitude of both metal enrichment factors (EF) and geoaccumulation indices (I(geo)) suggested that pollution with Ag, Cd, Cr, Cu and Zn was occurring in the estuaries and Port. Risk analysis also suggested that Ag and Ni concentrations were sufficiently elevated as to cause adverse biological effects in the study area. Although metal concentrations in western Bohai Bay were of less concern, a positive relationship between EF values and excess (210)Pb activity for several metals suggested that their concentrations were increasing over time.  相似文献   
333.
Urban heat island effect refers to the phenomenon that ambient air and surface temperatures in urban areas are several degrees higher than surrounding rural areas. Higher temperatures not only impact the comfort of urban dwellers, but also increase energy use, ozone production, and the risk of death for humans in a heat wave. Our research focuses on the variation in land surface temperature in the Gywnns Fall Watershed, Maryland. We found that land surface temperature is highly variable spatially, resulting in "hotspots" within the heat island. We further explore how this temperature variation relates to social factors on the scale of the census-based block group. We show that land surface temperature is statistically higher in block groups that are characterized by low income, high poverty, less education, more ethnic minorities, more elderly people and greater risk of crime. These variables were mapped to evaluate the spatial relationship of land surface temperatures to social factors. This spatially explicit approach facilitates identification of specific areas to prioritize for heat prevention and intervention efforts. We demonstrate, through an exercise, how incorporating data on land surface temperature and social factors into heat intervention strategies could contribute to efficient allocation of limited resources and services. The exercise also indicates where heat prevention efforts, such as tree-planting programs, are most needed to help reduce heat exposure and moderate the urban heat island effect.  相似文献   
334.
简要介绍了城市热环境的形成因素、机理和危害;基于《成都市城市热岛效应的遥感研究》成果,分析了成都城市热环境所具有的环型特征及其成因;探讨了改善热环境的方法和对策措施。这对于环境保护、城市的可持续发展,建设"世界现代田园城市"等具有现实意义。  相似文献   
335.
基于中巴CBERS-2B卫星影像,分析环境监测对影像地图的需求,探讨制作《桂林城区环境监测影像地图》的方法。在影像地图制作中,以GPS的SBAS信号定位,采用WGS84坐标系统,对道路河流等矢量层和监测专题要素层作了专门处理,还讨论了卫星影像在城区环境监测中的应用,探索环境监测遥感影像专题地图的特点、方法、技术难点和需注意的一些问题。  相似文献   
336.
Sustainable development or sustainability has been highlighted as an essential principle in urban master planning, with increasing recognition that uncontrollable urbanization may well give rise to various issues such as overexploitation of natural resources, ecosystem destruction, environmental pollution and large-scale climate change. Thus, it is deemed necessary to modify the existing urban and regional administrative system so as to cope with the challenges urban planning is being confronted with and realize the purpose of urban sustainability. This paper contributed to proposing a mechanism which helps to make urban planning with full consideration of issues with respect to sustainable development. We suggested that the integration of urban planning, SEA and ecological planning be a multi-win strategy to offset deficiency of each mentioned political tool being individually applied. We also proposed a framework where SEA and ecological planning are fully incorporated into urban planning, which forms a two-way constraint mechanism to ascertain environmental quality of urban planning, although in practice, planning and SEA processes may conditionally be unified. Moreover, as shown in the case study, the integration of the three political tools may be constrained due to slow changes in the contextual factors, in particular the political and cultural dimensions. Currently within the context of China, there may be three major elements which facilitate integration of the three political tools, which are (1) regulatory requirement of PEIA on urban planning, (2) the promotion or strong administrative support from government on eco-district building, and (3) the willingness of urban planners to collaborate with SEA experts or ecologists.  相似文献   
337.
王健  李双革 《火灾科学》2013,22(4):181-187
根据2003年-2006年浙江、武汉两地火灾事件发生情况,应用变异系数、法诺因子、阿伦因子的统计分析方法,对城市火灾事件的时间标度行为进行了分析。结果显示,城市火灾序列具有一定的时间丛集性特征,且在达到一定的时间尺度后呈现出较为明显的分形特征,该分形自相似性特征具有普适性和稳定性。同时发现,一定时间尺度范围内城市火灾时间序列的分形特征与时间窗口的取值无关。  相似文献   
338.
垫江县次级河流部分水质指标不容乐观,以种植污染、养殖污染和生活污染为代表的农村面源污染日渐成为垫江河流污染的主要因素。改变垫江河流水质现状,必须尽量减少化肥农药施用,改变传统养殖模式,完善农村垃圾收运系统,加快建设农村废水治理设施。  相似文献   
339.
贵阳市生活垃圾处理存在公众环保意识不强、垃圾处理方式单一、设施落后和资金不足等问题,可从加强宣传与垃圾处理技术研究、推进管理体制建设和制定法律法规等方面改善贵阳市生活垃圾处理现状,以全面落实各项政策,推进城市生活垃圾处理工作,促进城市可持续发展。  相似文献   
340.
以深圳市荔枝湖为例,通过枯水期历时8个月的水质连续监测,分析臭氧技术在修复城市湖泊水质中的作用及效果。结果表明,监测期间湖水CODMn≤10mg/L,氨氮<0.6mg/L,总磷<0.08mg/L,透明度在60~120cm间,水质满足景观水体要求,表明应用该技术可以取得较好的修复效果。  相似文献   
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