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961.
城市生态规划的理论与方法   总被引:14,自引:0,他引:14  
综述城市土地利用生态规划和城市生态系统对策规划的状况,分析并提出了城市生态规划的两种类型,即生态规划方法和城市生态系统水平上进行的生态对策规划,并对这两种生态规划的发展进行了探讨。  相似文献   
962.
以碱渣(白泥)和生活垃圾按不同比例混合填埋,模拟真实垃圾填埋场的垃圾降解条件,进行垃圾降解实验以探索白泥存在对垃圾填埋场垃圾降解过程的影响。通过21周的室内模拟实验,垃圾填埋时填加白泥可以提高渗滤液出水的pH值和电导率DS值,降低出水的COD值。得出垃圾填埋时加入适量白泥是经济有效的固体废弃物处理处置方法的结论。  相似文献   
963.
城市地下交通联系隧道烟气控制探讨   总被引:1,自引:0,他引:1  
为了给城市地下交通联系隧道(UTLT)防排烟系统设计和人员应急救援提供参考依据,以重庆某UTLT二期工程一段主隧道为例,开展全尺寸火灾试验,探讨了横向排烟方案的烟控效果,并验证了Alpert顶棚最高温升衰减模型。结果表明,UTLT主隧道段采用横向排烟方案,当防烟分区长度为120 m时,采用的排烟量设计方法是合理的。当隧道为上坡时,最有利的烟气控制模式为同时开启着火分区及下游相邻分区的排烟系统和与排烟分区紧邻的上、下游两个分区的补风系统。隧道顶部烟气最高温升衰减规律为:下游距火源无量纲距离r/H0.57及上游部分,呈指数衰减;下游距火源无量纲距离r/H0.57部分,呈幂函数衰减,且衰减程度与排烟方案有关。  相似文献   
964.
Objective: The ability to detect changing visual information is a vital component of safe driving. In addition to detecting changing visual information, drivers must also interpret its relevance to safety. Environmental changes considered to have high safety relevance will likely demand greater attention and more timely responses than those considered to have lower safety relevance. The aim of this study was to explore factors that are likely to influence perceptions of risk and safety regarding changing visual information in the driving environment. Factors explored were the environment in which the change occurs (i.e., urban vs. rural), the type of object that changes, and the driver's age, experience, and risk sensitivity.

Methods: Sixty-three licensed drivers aged 18–70 years completed a hazard rating task, which required them to rate the perceived hazardousness of changing specific elements within urban and rural driving environments. Three attributes of potential hazards were systematically manipulated: the environment (urban, rural); the type of object changed (road sign, car, motorcycle, pedestrian, traffic light, animal, tree); and its inherent safety risk (low risk, high risk). Inherent safety risk was manipulated by either varying the object's placement, on/near or away from the road, or altering an infrastructure element that would require a change to driver behavior. Participants also completed two driving-related risk perception tasks, rating their relative crash risk and perceived risk of aberrant driving behaviors.

Results: Driver age was not significantly associated with hazard ratings, but individual differences in perceived risk of aberrant driving behaviors predicted hazard ratings, suggesting that general driving-related risk sensitivity plays a strong role in safety perception. In both urban and rural scenes, there were significant associations between hazard ratings and inherent safety risk, with low-risk changes perceived as consistently less hazardous than high-risk impact changes; however, the effect was larger for urban environments. There were also effects of object type, with certain objects rated as consistently more safety relevant. In urban scenes, changes involving pedestrians were rated significantly more hazardous than all other objects, and in rural scenes, changes involving animals were rated as significantly more hazardous. Notably, hazard ratings were found to be higher in urban compared with rural driving environments, even when changes were matched between environments.

Conclusion: This study demonstrates that drivers perceive rural roads as less risky than urban roads, even when similar scenarios occur in both environments. Age did not affect hazard ratings. Instead, the findings suggest that the assessment of risk posed by hazards is influenced more by individual differences in risk sensitivity. This highlights the need for driver education to account for appraisal of hazards’ risk and relevance, in addition to hazard detection, when considering factors that promote road safety.  相似文献   

965.
The provision of green and open space in the face of wider development pressure is a key urban challenge. Despite this, few studies have critically investigated the quality of life implications of such provision. This paper focuses on perceptions of built environment factors and their influence on neighbourhood quality of life. Data are drawn from a household survey questionnaire completed by 483 residents living in three neighbourhoods in Dublin, Ireland – an inner city neighbourhood, a suburb and a peri-urban settlement. Positive perceptions of green and open space were identified as important predictors of high levels of neighbourhood satisfaction, surpassed only by dwelling characteristics. This suggests that development strategies which fail to provide for properly planned green and open spaces may be detrimental to neighbourhood quality of life. Furthermore, the results suggest a need for design solutions which consider neighbourhood typology in achieving improved neighbourhood quality of life.  相似文献   
966.
Water is a salient issue in the Intermountain West of the United States (U.S.), with concerns ranging from water scarcity and drought to intermittent flooding and water quality risks. This paper investigates coverage of water issues across seven newspapers in the core of the U.S. Intermountain West region. Newspapers have the potential to set agendas and influence perceived salience of issues among consumers. The Intermountain West region shares common concerns about water supply and demand, climate change, and water quality. We investigate whether or not local daily newspaper coverage of water issues provides a more local or regional sensitivity. Findings from this exploratory study reveal differences in water coverage across local daily newspapers. The overall volume of water‐related articles differed across newspapers as did proportion of articles on specific water topics and connecting issues. Coverage of local issues was more dominant than might be expected given mass media trends, but water geography in articles extended across the U.S. and the world in every newspaper studied. Variations in newspaper coverage of water issues suggests more local nuance persists despite the experience of common water issues across the region.  相似文献   
967.
国家公园建设背景下的公益型保护地研究进展   总被引:1,自引:1,他引:0       下载免费PDF全文
当前我国自然保护地体系改革正处于关键时期,公益型保护地是一种利用社会公益力量,由政府监督、民间管理并协调保护与发展的新型保护地模式。该模式注重社会公益力量在自然保护地建设中的作用,能够补充已有保护地资金、技术和人力的不足,填补了我国目前保护地体系的空缺。本文论述了国家公园建设背景下的公益保护地的内涵,分析了当前公益保护地的特征,讨论了国内外公益型保护地的运营管理机制,包括土地权利的获得、基于协议保护机制的保护地运营、特许经营在保护地的实施和社区保护模式的成功经验。今后我国公益型保护地的建设应鼓励公益组织与民间力量参与,在管理理念上应坚持保护第一和公益性,促进管理体制转变和科学划定界限,并完善公益组织参与保护地建设的激励和监督机制。  相似文献   
968.
薛海  张帆 《自然资源学报》2020,35(4):937-949
为研究降水量与大气污染物之间的关系,依据2017年全国113个环保重点城市大气质量数据,得出城市聚类空间分布规律及两者之间线性拟合方程。基于南北降水量分布特性与城市空气污染指数,采用模糊聚类法对具有不同亲疏程度的城市进行类别划分,运用Spearman相关性与拟合方程对大气污染特征值与降水量进行分析。结果表明:随着聚类种数增多,城市聚集在空间分布上由“环环相套”发展为“依流域分布”,降水量与大气污染物浓度呈现负向关联性,晋冀鲁豫陕省份污染最严重。采用Kolmogorov-Smirnov检验法,得出NO2、O3、PM2.5总体分布符合正态分布,SO2、PM10、CO既不符合正态分布,也不符合均匀、指数分布,它们与降水量的相关系数为:-0.316、-0.238、-0.332、-0.617、-0.574、-0.695;线性拟合方程系数处于 [-0.031, -0.008] 之间,降水量与大气污染物浓度之间负相关性明显。研究结果有助于了解和认识降水量对城市大气环境变化的影响。  相似文献   
969.
城市生态空间冲突分析与系统优化方法   总被引:2,自引:2,他引:0  
为适应国土空间整合理论方法的迫切需求,建立由冲突源、冲突区、冲突影响组成的城市生态空间冲突分析框架,其案例应用表明:城市生态空间的社会经济第一冲突源并不突出,政策驱动力构成首要冲突源;城市汇水区渗透性能下降,产流增加,汇流速度加快,形成上游高地型、中下游沿岸型、下游低洼型及沿山型等4种冲突类型,采用城市雨洪模型(SWMM)辨识出4种内涝区及分布类型;针对冲突源、空间优化核心和末端排水建立城市生态空间系统优化目标体系,重点提出“点线面”结合的空间优化核心路径。研究为国土空间整合提供理论与方法支撑,并涵盖国际雨洪管理演替过程,有助于对当前大规模土地开发转型及海绵城市建设理念的本土认识。  相似文献   
970.
基于广州市2009,2000和1990年工业、交通、生活能源统计数据,通过能源清单法估算出广州市对应年份的人为热排放量,再通过在WRF模式中引入2009,2000和1990年的下垫面数据和人为热排放方案,对2005,2012和2017年广州市的3次持续高温过程进行模拟,从而评估不同年代人为热排放水平对广州市极端高温天气的影响.结果表明,模拟的2m气温较为准确,能合理模拟出城市地区的热岛效应,但对极端高温的模拟略有偏低,而引入人为热有助于改善模拟结果.在case2012中,2009,2000和1990年3种人为热排放水平使广州城市下垫面的平均气温分别上升0.53,0.44和0.13℃,热岛强度增强0.43,0.38和0.13℃.3个模拟个例的结果均表明,日间的人为热排放比夜间大,但夜间气温及热岛强度的变化比日间要明显.  相似文献   
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