重工业城市——柳州市热岛效应的空间分布和时间演变

柳州市作为广西最大的工业城市、国家Ⅱ型大城市和中国五大汽车城之一,近年来其城市规模不断扩张,工业化进程不断加速使得城市热岛现象表现得越来越显著,但对柳州市热岛效应研究很少,尤其是多年连续遥感监测研究尚属空白。本文主要研究柳州市区城市热岛效应现状及其影响因素。通过辐射传输方程法反演柳州市近20年地表温度,分析其影响因素,阐明地表温度与城市发展、地形、下垫面、地物光谱的关系。研究结果表明:柳州市热岛效应基本呈"点状→面状→带状"时空演变规律,与城市规模扩大、经济发展加速密切相关;不透水面对热岛效应的促进最强,植被对热岛效应的抑制最有效;对重工业城市热岛效应的研究而言,相较于羟基特征值,铁染特征值可以作为更好的指标。根据柳州市热岛效应的时空演变规律和发展趋势,对城市工业布局和建设规划提出科学合理的建议。     

利用Landsat7反演的亮温与土地覆盖类型相关性分析

随着城市人口的急剧增加,城市建筑规模迅速膨胀,大量热源集中排放,产生了城市内部温度明显高于郊区的特殊城市气候现象,即“热岛效应”.以安徽省芜湖市为研究区域,采用GIS叠加分析方法、缓冲区分析方法进行地表辐射亮温与土地覆盖类型的相关性研究.研究结果表明,辐射亮温与地表类型有明显的相关关系,建筑与辐射亮温的相关系数为0.87,植被、水体与辐射亮温的相关系数分别为0.59、0.78.人工建筑因素是产生热岛效应的主要原因之一,加大植被、水体在城市土地用地中的比重,是控制城市热岛效应行之有效的方法,而且利用辐射亮温图可很好地指示城市土地覆盖类型在时间上和空间上的变化.     

空中花园的作用

正当绿化覆盖率达到40%以上时,热岛面积可减少四分之三,当绿化覆盖率达到60%以上时,热岛效应将基本被控制。近日,"2016昆明·世界生态城市与屋顶绿化大会"在昆明召开,来自法国、德国、美国及中国的500多名专家学者、业界精英和企业家汇聚一堂,剖析了屋顶绿化、墙体绿化、建筑绿化在海绵城市建设中的作用,就立体绿化解决城市中出现的热岛效应、内涝、雾霾等问题进行了深度探讨。具有突出的生态价值在此次大会上,世界屋顶绿化技术联盟主席曼弗雷德·科勒介绍了雨水收集在绿化中所起到的作用;美国屋顶绿化专家埃德蒙·斯诺德格拉斯引用"多肉"     

基于AVHRR的成都平原城市热岛效应演变趋势分析

作为城市气候主要特征之一的热岛效应有日渐明显的趋势，给城市发展和市民生活带来一系列负面影响。对2000～2006年春季下午NOAA气象卫星遥感数据的处理和分析发现，随着城市的扩张，成都平原城市热岛效应的规模呈扩大趋势。成都市区热岛强度一般为5℃-7℃，局部地方极值可达8℃以上；市中心区热岛强度相对减弱，东部工业区热岛高温区面积逐渐缩小，市区西南部热岛明显发展，致使2003年起热岛次高温区在二、三环路附近大致呈环状分布。热岛演变与近几年城市建设和改造活动密切相关。研究成果为政府相关部门缓解热岛效应、改善人居环境提供了参考依据。     

城市化对城市气候影响的实证分析——以济南市为例

近10年来,我国城市化的快速推进不但对区域经济社会发展具有深远意义,而且对城市的小气候也产生了一定影响.以济南市为研究区域,分析了近10年济南市气温和降水的变化态势,考察了城市发展对气候的相关影响,结果发现济南市存在显著的热岛效应、雨岛效应.在此基础上建立了城市发展与城市气候变化之间的回归模型,证明到目前发展阶段,济南市城市发展对气候的影响并不完全符合库兹涅茨曲线特征.     

城市化及其对大气环境的影响

中国城市化的快速发展与能源消耗的迅速增加,给中国城市带来了众多大气环境问题。城市化不仅造成了如热岛效应等城市周边气候的变化,还带来了酸雨频发、空气颗粒物污染加重和汽车尾气污染严重等城市环境问题。对此,应当从科学编制城市发展规划,合理调整经济结构,加强环境管理与污染治理,增加城市绿化面积等方面入手,改善城市大气环境。     

永定河(山峡段)补水成效分析

为改善永定河(山峡段)常年断流、河床沙化，水生态环境破坏严重等问题，门头沟区政府从2019年起开始对永定河(山峡段)进行生态补水，用来改善、修复、恢复生态系统节后功能和自我调节能力，促进绿色可持续发展，目前已初见成效。为进一步量化补水成效，以便政府部门决策，以生态补水数据、地面气象监测数据、环境数据为基础，综合运用卫星遥感监测数据，通过对2019～2021年间北京市门头沟区永定河(山峡段)补水后的生态变化情况进行分析，结果表明，永定河(山峡段)主河道河面面积约增加了一倍，主要河段河水水质明显改善；主河道周边1km范围植被覆盖率增长了6倍，植被生态质量增长了近4成，地表热环境指数均呈下降趋势，沿河周边村落热岛效应明显改善。本研究量化给出相关政府部门多年来永定河治理的成效，为相关政府行政部门研究和制定永定河生态修复工程等提供科学支持，为永定河后续污染防治提供理论基础。     

绿色校园环境的建设与评价

1．绿色校园环境建设有利于城市生态环境的可持续发展。城市化是社会进步的表现，是现代化的标志。但在城市化的过程中，由于没有协调好人与环境的关系，出现了严重的大气、水、固体废弃物污染、水资源短缺、绿地少、热岛效应等诸多城市环境问题。同时城市发展过程中也存在着自然和历史文化遗产的破坏问题。企事业单位、社区和学校等是构成城市的基本单元，中小学校园由于分布比较分散，就个体来看虽然面积不大，但总的数量不小，消耗着大量资源，同时也排放不少的废弃物。多年来中小学校园环境建设在注重建筑美学、现代化方面下了不少工夫…     

高考,直面环境保护

近年来，各地高考的各科试卷中，越来越多地出现了有关环境保护的试题，尤其在地理和综合考试中，环保更是每次必考的主题。以2002年全国文科综合试卷为例，有两道以环境问题为背景的试题。1．在大城市提倡的营建“绿色屋顶”和“绿色阳台”，其改善环境的重要作用是：（B）A．减少城市的噪音和光污染B．减轻热岛效应和美化环境 C．减轻光化学烟雾的污染 D．降低空气中可吸入颗粒物的数量2．我国在城市绿化中因使用杀虫剂而污染了地下水，下列绿化方式中污染最严重的是：（D）A．落叶阔叶树林 B．常绿针叶树林 C．“绿色屋顶”和“…     

基于国产自主新能源汽车电驱动系统量产关键技术研究

新能源汽车电驱动系统实现了量产,进行了产品深度集成技术研究、物料技术研究、总成验证技术研究、产品量产阶段的质量控制研究以及电装工艺评价技术研究等并实现了低成本与高可靠的总体要求,用户反馈良好。     

Is everyone hot in the city? Spatial pattern of land surface temperatures,land cover and neighborhood socioeconomic characteristics in Baltimore,MD

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.     

城市热岛效应的研究模型

城市热岛不但影响城市气候，而且严重影响城市的大气环境，城市发展的多样性决定了城市热岛的复杂性、研究模型的多样性。本文通过对城市热岛常用的研究模型进行了分析、比较，为城市热岛研究模型的选择和进一步研究城市热岛的机理以及城市热岛对城市环境的影响提供了参考依据。     

Exploring the relationship between residential segregation and thermal inequity in 20 U.S. cities

A combination of the urban heat island effect and a rising temperature baseline resulting from global climate change inequitably impacts socially vulnerable populations residing in urban areas. This article examines racial/ethnic and socioeconomic inequities in the spatial distribution of exposure to urban heat in the context of climate justice and residential segregation in the U.S. An urban heat risk index (UHRI) is calculated from measures of land surface temperature, structural density, and vegetation abundance, acquired from summer 2010 remote sensing imagery. Twenty of the largest metropolitan statistical areas (MSAs) in the U.S. are selected and analysed using census tract-level socio-demographic data from the U.S. Census. Multilevel modelling is utilised to examine the statistical associations between urban heat, minority status, socioeconomic disadvantage, and MSA-level segregation of racial/ethnic minority groups. Variables representing socioeconomic status (i.e. household income, home ownership, and education level) are consistently and significantly associated with greater urban heat exposure. Minority status and measures of segregation have a significant but varied relationship with urban heat exposure, indicating that there are inconsistent associations with urban heat due to differing social geographies. Urban heat and social vulnerability present a varying landscape of thermal inequity in different metropolitan areas, associated in many cases with residential segregation.     

EXTRA URBAN AND INTRA URBAN RAINFALL ENHANCEMENT BY A MEDIUM SIZED CITY1

An experiment on urban effects of warm season rainfall of a moderately sized city and its downwind towns found no evidence of global enhancement. However, there are grounds for believing that the intra urban distribution of precipitation is influenced by urban variables among which air pollution and urban roughness are considered primary. The presence of an urban heat island did not appear to improve rainfall. On the contrary, it appears to be a factor in the relative aridity of the downtown sector of the city.     

Managing the adverse thermal effects of urban development in a densely populated Chinese city

Guangzhou city in South China has experienced an accelerated urban development since the 1980s. This paper examines the impact of the urban development on urban heat islands through a historical analysis of urban-rural air temperature differences. Remote sensing techniques were applied to derive information on land use/cover and land surface temperatures and to assess the thermal response patterns of land cover types. The results revealed an overriding importance of urban land cover expansion in the changes in heat island intensity and surface temperature patterns. Urban development was also related to a continual air temperature increase in the 1980s and 1990s. The combined use of satellite-derived vegetation and land cover distributions with land surface temperature maps provides a potential useful tool for many planning applications. The city's greening campaigns and landscaping designs should consider the different cooling effects of forest, shrubs and grassy lawns for temperature control and should plant more tall trees.     

Long-term coal gasification-based power plants with near-zero emissions. Part A: Zecomix cycle

These two part papers analyse three plant configurations for high efficiency, near-zero emissions power generation from coal, suitable for long-term installations. In the first part the Zecomix cycle, a novel power plant based on various innovative processes, is presented. Zecomix plant is based on a coal hydrogasification process, using recycled steam and hydrogen as gasifying agents, to produce a CH₄ rich syngas. Methane is then converted to an H₂/H₂O based syngas and CO₂ is captured, by reacting in two carbonator reactors with CaO-based solid sorbent. CaCO₃ produced in carbonators is thermally regenerated in a calciner. The synthetic fuel is burned with oxygen in a semi-closed high temperature steam cycle, with a supercritical heat recovery.The paper presents a detailed analysis of the thermodynamic aspects of the process, with the scope of assessing its potential performance in terms of efficiency and emissions. Main operating parameters of the chemical island (e.g. hydrogasifier and calciner pressure, steam flow rates to carbonators, syngas recycle fraction) and of the power island (e.g. pressure ratio, turbine inlet temperature and reheat pressure) were varied in order to evaluate their effect on plant performance and to optimize the process. Critical issues are specifically discussed: the calcination process, the calcium oxide utilization in carbonators, the cooling requirement of the high temperature turbine, the presence of incondensable species in the steam cycle. An accurate performance estimation is therefore developed by considering advanced components, as an evolution of today's technology, excluding unproven devices whose feasibility cannot be anticipated.Depending on sorbent utilization, a net plant efficiency of 44–47% with a virtually complete carbon capture was obtained, a very interesting result with respect to other proposed coal-fired power plants with carbon capture. The high complexity of the chemical island and the importance of a good sorbent performance should be however taken into account for a fair comparison with other plant concepts. Further experimental investigations are mandatory to demonstrate the technical and economical feasibility of the Zecomix plant.     

能值理论在海岛生态旅游中的应用研究

21世纪是海洋的世纪,大力发展海洋经济成为全世界的共同目标。海岛作为“人类开发海洋的远涉基地和前进支点”被大规模开发,其主要开发利用方式——海岛生态旅游也蓬勃发展。在此背景下,如何协调海岛生态环境与旅游经济的关系成为人们关注的焦点,也是海岛生态旅游可持续发展亟待解决的问题。运用能值理论对海岛生态旅游系统进行研究,构建海岛生态旅游系统能值指标体系,定量分析整个系统的结构、功能、旅游经济效益、生态效率和综合状况,为海岛生态环境资源和旅游经济活动的评估提供客观标准,并为海岛生态旅游可持续发展研究提供科学的依据。     

Integration of technologies and alternative sources of water and energy to promote the sustainability of urban landscapes

Recent research has highlighted the positive role of green areas in urban environments, providing numerous social, environmental and economic services, such as mitigation of the urban heat island effect, storm attenuation, increased water infiltration into the soil, reduction of noise and air pollution, among others. However, the maintenance of green areas may result in high consumption of water, reaching 50% of the total consumption in some municipalities, and energy, becoming a reason of concern. The present study aimed to integrate techniques and technologies that promote the automatic and efficient irrigation of urban landscapes, using alternative sources of energy and water, toward its sustainability. The conceptual unit was able to reduce in 64% the water consumed in irrigation. Rainwater met 69% of the demand and the photovoltaic system supplied all the energy required. The economic feasibility analysis showed that the conceptual unit is financially unfeasible, under the conditions of this study. However, with some interventions for reusing the surplus energy and water, and considering the higher fees charged by other cities, the investment became attractive. In this new scenario, the internal rate of return (15 years) was 27.3% and the discounted payback period was 4.9 years.     

Impact of land use and land cover changes on the ambient temperature in a middle scale city, Takamatsu, in Southwest Japan

There is a lack of information on urban heat island impact on the thermal environment due to low populated urban sprawl, although densely populated urban sprawl impact has been identified by several researchers. The Takamatsu area has recently developed in a low populated urban sprawl style without any increase in population. This paper examined the impact of a low populated urban sprawl on the thermal environment through an analysis of the last 30 years data set and investigated the contribution of vegetation fraction and population density to the temperature trend. As a consequence, it was shown that one of the most significant causative factors of temperature increase is an expansion of non-vegetated area even without population growth. This result implied that vegetated zones should be maintained in urban areas in order to realize sustainable urbanization.