屋顶绿化的生态功能分析

论述了屋顶绿化的生态功能,分析了限制我国屋顶绿化发挥生态功能的因素。在国内外研究基础上归纳了屋顶绿化的7种生态功能,包括:减轻城市排水压力、改善水质、净化空气、节约能源消耗、丰富城市的生物多样性、减少光污染和噪音污染。构建屋顶绿化限制因素的要素层和因素层,通过AHP方法进行分析得出限制我国屋顶绿化生态功能的前三大限制因素分别为:"屋顶绿化相关政策和法律不健全"、"政府对屋顶绿化的发展缺乏政策支持"、"增加了设计和建造费用"。     

绿色屋顶微气候调节作用研究

中国城乡建设为城市带来经济快速增长的同时不可避免地导致一系列城市问题,面对用地紧张与城市环境问题的矛盾,建筑屋顶成为可利用的空间,因此利用大面积的建筑硬质屋顶构建绿色屋顶具有缓解部分环境问题的巨大潜力。屋顶绿化作为一种特殊的绿化形式,经过合理的屋顶界面处理可以具有类似城市绿地的生态调节作用,如改善屋顶微气候,滞纳雨水,降尘减污,缓解城市热岛效应等。主要梳理了屋顶绿化的各项生态功能,重点整理屋顶绿化对微气候的调节功能,并通过对本地区商场顶层屋顶绿化进行温湿度测量试验,探究其不同景观元素对微气候的调节功能。     

浅谈屋顶绿化的功能及应用

探讨屋顶绿化美化环境、遮荫调温、保护生态、环保节能等方面的功能，阐述屋顶绿化设计施工中的技术要点、植物选择原则，以及后期养护管理的注意事项。     

佛甲草屋顶绿化建造技术

全生态屋顶防水隔热绿化技术施工结构层的排列顺序从下至上为:防水层、隔热层、隔根膜、过滤层、营养土层、绿化植物。结构层次科学合理,可以实现防水、隔热节能、绿化、环保四位一体的功能,并能有效延长防水层的寿命,把屋顶建成一个全生态的绿色花园。     

佛甲草屋顶绿化建造技术

全生态屋顶防水隔热绿化技术施工结构层的排列顺序从下至上为:防水层、隔热层、隔根膜、过滤层、营养土层、绿化植物.结构层次科学合理,可以实现防水、隔热节能、绿化、环保四位一体的功能,并能有效延长防水层的寿命,把屋顶建成一个全生态的绿色花园.     

国内外屋顶绿化推广政策探析

在借鉴国外屋顶绿化的政策基础上,梳理与分析了我国国内典型城市现行政策情况,提出了相应政策推广的启示与建议。为不断加大和完善屋顶绿化推广政策,发挥其优越的生态、环保功能提供一定的参考。     

浅谈城市屋顶绿化

<正>1屋顶绿化概述城市屋顶绿化指在屋顶上种上植物。屋顶绿化除了具有一般绿化的生态、景观等效果外,还能有效地防止屋顶温度升高,从而减少温差对屋顶的破坏,其防水隔热和节能效果也很明显。据测试表明,夏季有屋顶绿化的顶层室内温度比未绿化的要低4~6℃左右,而冬季则能有效保温。屋顶绿化能避免屋顶出现极端温度并减少紫外线对屋顶的损害,绿化后的屋顶寿命比未绿化的长约3倍。经绿化的屋顶能够吸收空气中30%     

屋顶绿化的优点及国外政策借鉴

由于屋顶绿化在经济、社会、生态等方面拥有着众多的优势,世界许多国家制订了相应的屋顶绿化政策.现在了解国外屋顶绿化政策的基础上,对国外屋顶绿化政策进行分析,并根据我国屋顶绿化政策的现状及存在的问题,提出我国在屋顶绿化政策方面应该采取的措施,以达到加快我国屋顶绿化事业发展的目标.     

重庆市不同类型屋顶绿化生态效应研究

以重庆市园林事业管理局花园式屋顶绿化和重庆市风景园林规划设计院简单式屋顶绿化为研究对象,以未屋顶绿化为对照,通过分析比较屋顶绿化在降温、增湿和阻滞颗粒物等方面的生态效应.结果表明,屋顶绿化的生态效应明显,花园式屋顶绿化明显优于简单式.降温效应：简单式日均降温2.81℃,花园式日均降温4.54℃,最大降温效应高达9.35％;增湿效应：简单式日均增湿7.97％,花园式日均增湿11.32％,最大增湿效应高达15.09％;阻滞颗粒物效应：简单式阻滞悬浮颗粒物效应平均为5.99％,花园式平均阻滞效应为8.92％,最大阻滞效应高达16.19％.以花园式屋顶绿化综合生态效应为最高.     

北京市绿色屋顶空间发展的困境与对策

北京市的屋顶空间绿化建设在社会、经济和生态方面具有重大意义,经过10余年的建设已经取得了一定程度的发展,但发展速度与建设效果并不尽如人意。根据对北京市屋顶建设现状的调查分析,提出对发展困境与误区的思考,尝试梳理原因,更加精准地解析、依循设计原则,寻找设计对策,通过对屋顶特色的深入挖掘与辨析,寻找更恰当的功能,总结屋顶绿化空间的关键技术点,解析生态设计宣传的助推作用,推动、加速屋顶空间建设的步伐。     

屋顶绿化降温效果研究

随着屋顶绿化的发展,研究屋顶绿化作为改善城市生态环境的策略之一越来越受到人们的重视。为了研究屋顶绿化对建筑内、外表面的降温效果,选取屋顶绿化实地测量,通过对测量数据的量化分析,结合国内外相关的研究方法和长沙市独特的气候背景,论证屋顶绿化后建筑温度的变化及对于城市热环境的改善。     

Assessing the potential of strategic green roof implementation for green infrastructure: Insights from Sumida ward,Tokyo

Urban green spaces, and green infrastructure more generally, provide multiple benefits that can enhance urban livability and sustainability. These range from the mitigation of air pollution and urban heat island (UHI) effect, to multi-dimensional benefits to human wellbeing and biodiversity. However, the expansion of urban green spaces is not always feasible in many cities. In such urban contexts, there have been proposals to utilize rooftops as green roofs in order to gain some of these benefits. This study spatially identifies areas where roofs have the potential to provide different types of benefits associated with urban green spaces if they are retrofitted with green roofs. Through a GIS-based approach we catalogue available roof space in Sumida ward in Tokyo for green roof implementation, and subsequenlty evaluate the potential of each roof patch to offer four types of benefits if retrofitted with a green roof, namely UHI effect mitigation, air pollution mitigation, and benefits to subjective wellbeing and biodiversity. Approximately 25% of the total roof surface in Sumida ward can potentially be used for green roof implementation. Furthermore, about 5.2% and 59% of this area has a respectively high and moderate potential to provide all four benefits if retrofitted with green roofs. This could increase the extent of green spaces by 10% and 120% respectively across the Sumida ward. In this sense, green roofs can become a major element of green infrastructure with ripple positive effects for urban livability and sustainability through the provision of UHI effect and air pollution mitigation, and benefits to subjective wellbeing and biodiversity.     

重庆花园式屋顶绿化生态效益的初步研究

为了探讨屋顶绿化的生态效益,2013年7月选取重庆市园林事业管理局花园式屋顶绿化作为研究对象,以无绿化植物的屋顶水泥地作为对照,进行“乔-灌”、“灌-草”和草坪三种不同植物配置模式的气温、空气相对湿度、地表温度和空气中负氧离子含量测定。研究结果表明,屋顶绿化具有重要的生态效益,且不同植物配置模式的生态效益有较大差异。降温幅度为“乔－灌”（3．60℃）〉“灌～草”（2．68℃）〉草坪（1．43℃）,增湿幅度为草坪（29．42％）〉“乔-灌”（17．68％）〉“灌-草”（9．46％）,对地表温度的降低程度“乔－灌”（25．55℃）〉草坪（20．67℃）;屋顶绿化空气负氧离子含量此对照高33．73ions／m^3。     

Performance of native succulents,forbs, and grasses on an extensive green roof over four years in subtropical Australia

To achieve enduring low-maintenance green roofs that provide maximum benefit in the subtropics, plants need to be well adapted to the local climate with extensive green coverage. The use of native plants contributes to ecological restoration, yet there is very limited information available on their performance in the subtropics. This study aimed to determine the performance of nine species of Australian native forbs, succulents, and grasses in monofunctional and functionally-mixed plant communities on an extensive green roof in Brisbane over four years. Green coverage and survival were monitored via image analysis and observational visits. Forbs established slowly, but successfully (82 % green coverage, 67 % survival after four years) with species Hibbertia scandens (100 % survival) and Dianella brevipedunculata (58 % survival and extensive recruitment) performing the best. Grasses, including Themeda triandra, Poa labillardieri and Cymbopogon refractus, achieved a fast initial green coverage (47 % after 10 months), but showed high seasonal variability and declined to 2 %. Contrary to expectations, succulents performed poorly (<5 % green coverage, 14 % survival). Green coverage had an inverse trend to plant survival in successful plots (forbs, functionally-mixed) indicating a gap-filling effect by high performing species. Survival was more strongly linked to individual species than to functional type or plant community arrangement. Based on the results of this study, we recommend consideration of functionally-mixed green roof plantings with a variety of indigenous plants including forbs for low maintenance and resilient green coverage in the subtropics. Habitats that provided suitable plant species for this study were coastal headlands, dunes, montane areas, and open eucalypt forests. Analogous habitats in other regions can be explored to find new native plant species to increase the plant palette of potentially suitable species. It would be beneficial to trial more plants from these habitats over multiple years to increase the knowledge of suitable species available to green roof designers.     

Can green roofs help with stormwater floods? A geospatial planning approach

Increasing urbanization, impervious space, and the impact of climate change are threatening the future of cities. Nature-based solutions, specifically urban green infrastructures, are seen as a sustainable strategy to increase resilience against extreme weather events, including the escalating occurrence of stormwater runoff flooding. Consequently, urban planners and decision-makers have pushed their efforts toward implementing green infrastructure solutions to reduce the impact of stormwater floods. Among others, green roofs help store water and decrease stormwater runoff impacts on a local scale. This research aims to investigate the effect of surface permeability and green roof implementation on reducing stormwater flooding and subsequently provide urban planners with evidence-based geospatial planning recommendations to improve urban resilience in Helsinki. First, we modeled the current impact of stormwater flooding using the Arc-Malstrom model in Helsinki. The model was used to identify districts under high stormwater flood risk. Then, we zoomed in to a focus area and tested a combination of scenarios representing four levels of green roof implementation, two levels of green roof infiltration rates under 40-, 60-, 80-, 100 mm precipitation events on the available rooftops. We utilized open geographic data and geospatial data science principles implemented in the GIS environment to conduct this study. Our results showed that low-level implementation of green roofs with low retention rates reduces the average flood depth by only 1 %. In contrast, the maximum green roof scenario decreased most of the average flood depth (13 %) and reduced the number of vulnerable sites. The proposed methodology can be used for other cities to develop evidence-based plans for green roof implementations.     

Weather effect on thermal and energy performance of an extensive tropical green roof

This study investigated the weather effect on thermal performance of a retrofitted extensive green roof on a railway station in humid-subtropical Hong Kong. Absolute and relative (reduction magnitude) ambient and surface temperatures recorded for two years were compared amongst antecedent bare roof, green roof, and control bare roof. The impacts of solar radiation, relative humidity, soil moisture and wind speed were explored. The holistic green-roof effect reduced daily maximum tile surface temperature by 5.2 °C and air temperature at 10 cm height by 0.7 °C, with no significant effect at 160 cm. Green-roof passive cooling was enhanced by high solar radiation and low relative humidity typical of sunny summer days. High soil moisture supplemented by irrigation lowered air and vegetation surface temperature, and dampened diurnal temperature fluctuations. High wind speed increased evapotranspiration cooling of green roof, but concurrently cooled bare roof. Heat flux through green roof was also weather-dependent, with less heat gain and more heat loss on sunny days, but notable decline in both attributes on cloudy days. On rainy days, green roof assumed the energy conservation role with slight increase instead of reduction in cooling load. Daily cooling load was 0.9 kWh m^?2 and 0.57 kWh m^?2, respectively for sunny and cloudy summer days, with negligible effect on rainy days. The 484 m² green roof brought potential air-conditioning energy saving of 2.80 × 10⁴ kWh each summer, equivalent to electricity tariff saving of HK$2.56 × 10⁴ and upstream avoidance of CO₂ emission of 27.02 t at the power plant. The long-term environmental and energy benefits could justify the cost of green roof installation on public buildings.     

Importance of different components of green roof substrate on plant growth and physiological performance

Green roof substrate is arguably the most important element of a green roof, providing water, nutrients and physical support to plants. Despite this there has been a lack of research into the role that different substrate components have on green roof plant growth and physiological performance.To address this, we assessed the importance of three green roof substrate components (organic matter type, brick particle size and water absorbent additive) for plant growth and plant physiological performance. Lolium perenne (Ryegrass) was grown in eight substrates in a controlled greenhouse environment with a factorial design in composition of (i) small or large brick, (ii) conifer bark or green waste compost organic matter, and (iii) presence/absence of polyacrylamide water absorbent gel (‘SwellGel?’).We found that large brick substrates had a lower water holding capacity than small brick (?35%), which led to decreased shoot growth (?17%) and increased root:shoot ratio (+16%). Green waste compost increased shoot and root growth (+32% and +13%) shoot nitrogen concentration and chlorophyll content (20% and 57%), and decreased root:shoot ratio (?15%) compared to bark. The addition of swell gel increased substrate water holding capacity (+24%), which increased shoot growth (+8%). Total evapotranspiration (a proxy for potential cooling) was increased by greater shoot biomass and substrate water holding capacity. Overall, this study provides one of the first quantitative assessments of the relative importance of commonly used green roof substrate components. It is clear that substrate composition should be considered carefully when designing green roofs, and substrate composition can be tailored for green roof service provision.     

杭州市屋顶绿化现状调查研究

杭州市用于屋顶绿化的植物种类共计63科111属145种;从植物的观赏特性方面对应用状况进行分析,并依据园林布局形式和屋顶的开敞程度对杭州市屋顶绿化进行分类。结合实地调查,通过自身对比及与国外先进国家的屋顶绿化对比,发现杭州市屋顶绿化目前存在的问题并提出改进意见。     

An initial experimental assessment of the influence of substrate depth on floral assemblage for extensive green roofs

Extensive green roofs have the potential to be used as mitigation tools to compensate for urban habitat loss, but there is little information about how closely these systems emulate ground-based habitats. This study investigated the effect of limited substrate depth on plant assemblages in the initial phase of growth in extensive green roof substrates. Five replicate mesocosms (1 m²) for each of three design treatments: (A) 10 cm aggregate depth with green roof drainage and solid floor, (B) 15 cm aggregate depth with green roof drainage and solid floor, and (C) 15 cm aggregate depth on top of bare earth; were positioned at ground level. Each mesocosm had an identical growth substrate and was seeded with the same seed mix. Plant assemblages were analysed using point-quadrat methods. Significant differences in species composition were observed between treatments that seemed to be related to water availability. Even the deep (15 cm) solid floor green roof treatment showed many significant differences in floral assemblage compared to the identical treatment (C) where plants had access to water in the soil profile. Therefore, it is not possible to exactly recreate most ground-based urban habitats on roofs by simply copying the soil characteristics and floral composition found on the ground. Like for mitigation for habitat loss using extensive green roofs requires the careful manipulation of design elements in order to counteract the limited water availability on green roofs.     

“森林城市”模式与城市绿地园林景观及功能的弱化

“森林城市”的提法导致城市园林绿化建设模式产生一定的偏差,“森林城市”忽视了城市内绿地与城市外绿地功能的诸多差异,甚至导致城市园林绿地丧失其应该体现的园林艺术特征和休闲、游憩、娱乐、健身等综合功能。除生态效益之外,只有强调城市绿地的园林艺术特征和多功能性才能防止城市绿化中过密、过滥的“森林式”的种植模式。正确定位城市中心和城市外围两种不同地域绿地的功能和结构,并以生态的楔形绿地为桥梁是实现城内外绿地相互联系、功能互补的一个有效途径。