Dissertations / Theses on the topic 'Greenroof'

Throughout history, utopian ideals have existed promoting nature as a necessary affect for better aesthetic and psychological being. Yet, as human populations climb so do stresses upon the natural environment - therefore, bringing "the city in harmony with nature" becomes more challenging. Fortunately, hope exists through the use of greenroof technology. Greenroofs are a green space created by continuous layers of drainage, protection, growing medium, and plants either onto or integral to a roofing system. This paper explores extensive greenroofs, characterized by low-maintenance and shallow growing medium. Greenroof benefits (ecological, economical, aesthetic, psychological) are classified as: Market and Human. Further exploration of human-driven benefits result in the definitions of active and passive sensation (the division of sensation): Active sensation is the immediate, present, unimagined engagement of a specific sense. Passive sensation is the imagined perception (sensing) of an object or element. As defined, Active Sensations are real and, therefore, have limits/defects/boundaries; yet, Passive Sensations are imagined, and therefore, limitless. As alluded by William James, "The philosophy which is so important in each of us is not a technical matter; it is our more or less dumb sense of what life honestly and deeply means. It is only partly got from books; it is our individual way of just seeing and feeling the total push and pressure of the cosmos." The remainder of the document explores human-driven greenroof design; emphasizing design as a form of inquiry.
Master of Landscape Architecture

Greenroof systems have been shown to be an environmentally friendly alternative based on various factors; such as, reduced lifecycle cost, improved air quality, ambient temperature reduction, stormwater management credit, sustainability and preservation of the environment. Recent research studies attempt to determine the construction methods of an ideal greenroof for environmental purposes, yet there is an absence of standards for the best design required to achieve acceptable structural performance and sustainability under wind loads. As a result, there is a need to document the effectiveness of greenroofs under high wind events by addressing the following questions: Do winds have an effect on greenroof material loss? Do greenroof materials modify local pressure conditions that would need a modification to current design codes? Does the level of vegetation establishment affect the material loss and pressure distribution? This thesis first focuses on vegetated greenroof construction techniques and issues along with some of the most recent studies conducted by UCF researchers. Then, the literature focuses on wind uplift of vegetated roofs constructed using different wind erosion control methods with respect to vegetation cover, geosynthetic liners, and wind breaks. As part of this research, two monitoring systems with a grid of very low differential pressure transducers and a high speed anemometer were designed and implemented on the East and West coasts of Florida to collect data for the pressure distribution across the greenroofs in relation to wind direction and speed. In addition to this, the design of this monitoring system with specific information about the sensing and data acquisition systems is presented. Subsequently, the analysis of the monitoring data compares the peak wind gusts for each time interval to their corresponding pressure measurement to obtain pressure coefficients identified at each pressure node on the roof. Based on this analysis, pressure changes for hurricane speed winds are predicted to have an overall average uplift pressure envelope within ASCE Code 7-05 design standards with vegetation cover enhancing sustainability under wind events. For future studies, controlled field investigations to reduce in situ limitations due to natural climatic conditions as well as long term monitoring are discussed as recommended studies for the evaluation of wind effects.
M.S.C.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering MSCE

As the numbers of installed greenroofs continue to grow internationally, designing greenroof growing media to reduce the amount of nutrients in the stormwater runoff is becoming essential. Biochar, a carbon-net-negative soil amendment, has been promoted for its ability to retain nutrients in soils and increase soil fertility. This study evaluated the effect on water quality of greenroof runoff after adding biochar to a typical extensive greenroof soil. Prototype greenroof trays with and without 7% biochar (by weight) were planted with sedum or ryegrass, with barren soil trays for controls. The greenroof trays were subjected to two sequential 2.9 in/hr rainfall events using a rainfall simulator. Runoff from the rainfall events was collected and evaluated for total nitrogen, total phosphorus, nitrate, phosphate, total organic carbon, and inorganic carbon. Greenroof trays containing biochar showed lower quantities of nutrients in the stormwater runoff compared to trays without biochar. Biochar-amended soil with and without plants showed a 3- to 25-fold decrease in release of nitrate and total nitrogen concentrations, as well as a decrease in phosphate and total phosphorus concentrations release into the rainfall runoff. Phosphorus results from trays planted with sedum indicate that sedum interacted with both soils to cause a decrease of phosphorus in the greenroof runoff. In correlation with a visual effect in turbidity, biochar-amended soil showed a reduction of total organic carbon in the runoff by a factor of 3 to 4 for all soil and plant trays. Inorganic carbon was similar for all tests showing that inorganic carbon neither reacted with, nor was retained by, biochar in the soil. The addition of biochar to greenroof soil is an effective way to retain nutrients in a greenroof soil, reduce future fertilizer demands, and improve the water quality of the stormwater runoff by reducing nitrogen, phosphorus, and total organic carbon concentrations in the runoff water.

With growing concerns over human relations with respect to Nature within the Anthropocene increasingly expressed in terms of changing climates, the agentive relations between humans and the world come more sharply into anthropological focus. Cities, often described as devoid of Nature, are currently being recognised as one way to govern the twin problems of managing a changing climate and an increasingly compact city form. There are currently, 700 green (deliberately vegetated) roofs in place in London. This thesis examines the material culture of greenroofs, through a re-evaluation of J.J. Gibson’s Affordance Theory. Materials and plants in combination provide the conditions for agentive action, not only for flora and fauna but for people. I propose that these resulting socio-biological capacities be described as phyto-materiality. This phyto-materiality becomes central to flexible and ongoing classificatory practices which, in turn, enables greenroofs to become incorporated into a palimpsest of policymaking at the local and city levels and facilitates the mainstreaming of greenroofing practice. During a greenroofing project, phyto-materiality becomes central to achieve movement across geographical and organisational boundaries re-shaping the governance of London’s built environment and the working practices of professionals. However the material effects of greenroofing become problematic as imagined future plants become a source of concern for leaseholders or current flora and fauna escape the roof, revealing tensions and fractures in greenroofing practice. The thesis is informed by more than a year’s participant observation within a local authority and a network of greenroof designers, builders, ecologists, policymakers and ecological activists. Greenroofing comes out of an engagement with British environmental discourses and in making greenroofs and greenroof policy-making people remake themselves as greenroofers. For these respondents, phyto-materiality becomes both the ends-in-sight vision of, and the methodology for, ecotopia.

Une toiture végétalisée (TV) est un système complexe qui peut être décrit par ses propriétés, en considérant d'une part les propriétés de ses composants abiotiques (substrat et couche de drainage) et d'autre part ses composants biotiques (végétation, faune spontanée et microbiote). Comme dans tous les systèmes biotiques/abiotiques des interactions complexes se produisent. Tout d'abord, le système externe - introduit ici comme étant des facteurs - induit un effet de vieillissement qui se traduit par l'évolution des propriétés. De plus, les interactions entre les composants abiotiques et biotiques peuvent également induire une évolution des propriétés. Ces interrelations et interactions entre tous les facteurs et propriétés peuvent contrôler le niveau des performances qui pourraient être soumit à des changements dans le temps. Notre approche met en lumière la possibilité de simplifier les relations entre les performances de chaque facteur et donc de mieux comprendre l'évolution et les performances d'une TV. Ce besoin de recherche est né du fait que la plupart des études pertinentes menées à ce jour ont négligé cette dynamique temporelle de l'évolution des TV et des propriétés du technosol hautement réactives. Cette thèse vise à atteindre un point de croisement entre le vieillissement des matériaux inertes et la pédogenèse qui décrit l'évolution des milieux vivants puis à évaluer l'évolution des performances des TV au fil du temps. Pour ce faire, une méta-analyse a d'abord été menée, dont les principaux résultats ont mis en évidence que la plupart des facteurs et des propriétés ont une influence positive sur les performances des TV, montrant qu'il existe de nombreux leviers pour améliorer leurs performances et résoudre certains des principaux problèmes environnementaux urbains. Mais, considérant que ce recensement était loin d'être exhaustif, il a été noté qu'un énorme potentiel dans la détermination des performances des TV reste à découvrir. Des expériences ont été conduites afin de reproduire dans des conditions contrôlées certains facteurs considérés comme influents (e.g. pluie, végétation, alternance gel/dégel), sur des mésocosmes de 3 substrats de TV différentes choisis en fonction de leur composition et de leur granulométrie. Les propriétés de leurs substrats ont été suivies en suivant un protocole de vieillissement artificiel sur une période de 2 mois pour simuler l'évolution en temporelle. Nos résultats ont montré des preuves de pédogenèse précoce, en particulier pour le substrat le plus fin. Selon le substrat : i) la végétation stimule ou maintient la microbiologie ii) la pluie modifie la granulométrie par des processus de lessivage iii) le gel modifie la granulométrie par fractionnement. Il y a également un changement dans la structure porale, ce qui modifie les performances de rétention d'eau. De plus, les changements dans les performances des autres propriétés étudiées semblent plus dus à l'évolution temporelle qu'à une influence des facteurs. Le suivi des échantillons de référence ont révélé une diminution ou une augmentation du pH selon le substrat, de petites variations dans la microbiologie et dans les concentrations de carbone organique et d'azote total. Enfin, des prélèvements in situ, nous ont permis de mesurer l'évolution des propriétés vieillies de 7 substrats provenant de deux sites d'âges différents et de 3 végétations différentes. Elles ont révélé que l'évolution est principalement déterminée par l'âge ; les substrats les plus jeunes (3 ans) subissant une pédogenèse rapide par rapport aux substrats plus anciens (10 ans) dont l'évolution semble s'être relativement stabilisée. En considérant l'ensemble des résultats, on peut dire que dans les premières années, les trajectoires de pédogenèse des substrats de TV sont principalement dominées par la nature et la composition de leurs matériaux intrinsèques. Puis, après un certain temps, les facteurs semblent régir les performances
The green roof system is a complex system that could be described by its “properties”, considering on the nature and physical, chemical, and thermal properties of its abiotic components (i.e., substrate and drainage layers) and on the other hand its biotic components (i.e., vegetation, spontaneous fauna, and microbiota). As in all biotic/abiotic systems, complex interactions happen. First, the external system—here described as “factors”—induces an ageing effect that results in the evolution of “properties” over time (e.g., rain may induce leaching of fine particles; cold temperature may alter the vegetation development). Moreover, interactions between abiotic and biotic components may also induce evolution of “properties” (e.g., plant litter may increase the organic matter content in the substrate; decrease of the substrate physico-chemical fertility can decrease the biomass production). Eventually, such inter-relations and interactions between all “factors” and “properties” can control the level of performances that could be submitted to changes over time. Though the system is complex, our approach sheds light on the potential of simplifying each Factor property performance relations and hence understanding the system evolution and performances better. This research need originated from the fact that most of the relevant studies conducted to date have neglected these temporal dynamics of green roof evolution and their high reactive technosol properties. This PhD aimed to reach a crossroad point between ageing -of inert materials and pedogenesis- that describes evolution of living media and to evaluate the performance evolution of green roof over time. To evaluate this, first, a meta-analysis was conducted whose main findings highlighted that most factors and properties have a positive influence on the performances of green roofs, showing there are many existing levers to enhance the green roof performances and tackle some of the main urban environmental issues. But, considering that these lists were far from exhaustive, it was noted that a huge potential in determining green roof performances remains unearthed. Thus, experiments were designed and conducted with the purpose to reproduce certain factors considered as influential (i.e. rain, vegetation and freeze/thaw alternation), under controlled conditions, on mesocosms of 3 different green roof substrates chosen based on composition and granulometry. Their substrate properties were monitored over time through self-designed artificial aging over a period of 2 months to mimic real time evolution. Our results showed evidence of early pedogenesis especially for the finer substrate. Depending on the substrate: i) vegetation stimulates or maintains microbiology; ii) rain modifies granulometry through leaching processes; iii) frost modifies granulometry through fractionation. There was also change in the poral structure thus modifying the water retention performance. Other than that, the changes in the performance of other studied properties seem more due to the temporal evolution rather than factorial based. It was also noted in monitoring of the reference samples which revealed: a decrease or increase in pH depending on the substrate, small variations in microbiology and in organic carbon and total nitrogen concentrations. As a final step, in situ aged property evolution measurements from 7 substrates originating from two different sites of different ages and 3 different vegetation, revealed that the evolution is mainly driven by the age where the younger substrates (3 years) could be seen undergoing a rapid pedogenisis compared to the older substrates (10 years) whose evolution seem to have comparatively settled. Considering the results overall, it can be said that within the first years, the pedogenesis trajectories of green roof substrates are mostly dominated by the nature and composition of their parent materials. Then, after a while, the factors could take the lead

Die Verdunstung ist die Klimaanlage der Erde. Sie verbindet den globalen Wasserkreislauf mit dem Energiekreislauf. Die Komponenten des Wasser- und Energiekreislaufs stehen für jeden Standort in einem dynamischen Gleichgewicht. Mit der Ausführung von Bauvorhaben wird in das Gleichgewicht eingegriffen. Entscheidend für die Beurteilung der Folgen für die Umwelt sind die langfristigen Auswirkungen. Diese können durch den Vergleich langjähriger mittlerer Jahresbilanzen vor und nach der Bebauung aufgezeigt werden. Bei der Genehmigung neuer Baugebiete müssen diese Auswirkungen ein Entscheidungskriterium werden, wenn der Eingriff in den Naturhaushalt so gering wie möglich gehalten werden soll. Nur die Betrachtung von einzelnen Starkregenereignissen ist nicht ausreichen. Von der Versiegelung der Oberflächen ist die Verdunstung in der Jahresbilanz stärker als die anderen Komponenten des Wasserkreislaufs betroffen. Trotzdem werden bisher bei der Planung neuer Baugebiete hauptsächlich der Oberflächenabfluss und in zunehmendem Maße die Versickerung untersucht. Die Reduzierung der Verdunstung wird zumeist vernachlässigt. Ursache für diese Reduzierung ist die fehlende Zwischenspeicherung des Wassers. Das wirkt sich direkt auf den Energiekreislauf aus, da die nicht für den Verdunstungsprozess benötigte Energie in den bodennahen Schichten bleibt. Im ersten Teil werden die Einflussfaktoren auf die Verdunstung erläutert und ein Überblick über die Berechnungsmethoden gegeben. Im zweiten Teil werden die Oberflächen unbebauter und bebauter Gebiete systematisiert und in Landnutzungsarten unterteilt. Für diese werden die hydrologischen und energetischen Eigenschaften und deren Auswirkungen auf den Wasser- und Energiehaushalt erläutert und die mittleren Jahresbilanzen berechnet. Die tatsächliche Verdunstung wird auf der Basis der Gras-Referenzverdunstung und der Landnutzungsart ermittelt. Ausgangswerte sind langjährige meteorologische Jahresmittelwerte. Die Verdunstung von Wasserflächen wird mit dem Temperaturgleichgewichtsverfahren berechnet. Mit den vorgestellten Verfahren können Einzugsgebiete von Bebauungsplangröße untersucht werden. Es werden Lösungen zur Beibehaltung eines möglichst hohen Verdunstungsanteils in bebauten Gebieten vorgeschlagen. Ansatzpunkt ist dabei stets die Zwi-schenspeicherung des Regenwassers. Am wirkungsvollsten sind dabei Dachbegrünungen, Wasserflächen und Bäume. Das Verfahren wird an zwei Beispielen angewandt - die Erschließung eines Industriegebietes auf einer vorher land- und forstwirtschaftlich genutzten Fläche in Treuen im Vogtland und der Neubau einer Untergrundstation im Zentrum der schwedischen Großstadt Malmö
Evapotranspiration could be called the air-conditioner of the earth. It is connecting the water and the energy cycle. The components of the water and energy cycle are related to each other in a dynamic system. Urban development is interfering with this system. Changes of the water and energy balance resulting from construction can be calculated on the basis of long-standing annual average balances and compared with the balance in the catchment area before construction. Before granting building permission, the impacts on the water and energy balance should be evaluated in order to minimize interference with nature. Causing long-term impacts must be considered beforehand in planning. Coping only with design storm events does not suffice. Evaporation is more intensely affected by the paving of streets and squares and by constructing buildings then the other components of the water cycle. However, up to now, in the process of design and planning permission of new development areas, the focus is on runoff and, increasingly, on infiltration of rainwater. The large reduction of evaporation is mostly neglected. The reason for the reduction is the lack of buffer storage for water. Thus directly affects the energy cycle. Energy which is not used for evaporation remains in the near-ground layers. In the first part, the factors influencing evaporation are explained and an overview over the methods of calculation is given. In the second part all surfaces of urban and natural areas are systematized and subdivided into types of land use. The hydrological and energy properties as well as their effects on the water and energy balance are elucidated for this types of land use and their average annual balances are calculated. Solutions are presented for retaining in urban areas an evaporation rate as high as possible. Starting point hereby is always the buffer storage of rainwater. Most effective measures are the installation of rooftop greening, open water surfaces and trees. The calculations are performed on the basis of the FAO reference evaporation and the types of land use. Starting values are long-stand average annual meteorologic values. The evaporation of water surfaces is calculated with the temperature balance model. The method is applied to two examples showing the impacts of land use change on water and energy balance: the development of agricultural and forest land in Saxony into an industrial development site, and the impact of the construction of an underground station in the centre of the City Malmö, Sweden

Die Verdunstung ist die Klimaanlage der Erde. Sie verbindet den globalen Wasserkreislauf mit dem Energiekreislauf. Die Komponenten des Wasser- und Energiekreislaufs stehen für jeden Standort in einem dynamischen Gleichgewicht. Mit der Ausführung von Bauvorhaben wird in das Gleichgewicht eingegriffen. Entscheidend für die Beurteilung der Folgen für die Umwelt sind die langfristigen Auswirkungen. Diese können durch den Vergleich langjähriger mittlerer Jahresbilanzen vor und nach der Bebauung aufgezeigt werden. Bei der Genehmigung neuer Baugebiete müssen diese Auswirkungen ein Entscheidungskriterium werden, wenn der Eingriff in den Naturhaushalt so gering wie möglich gehalten werden soll. Nur die Betrachtung von einzelnen Starkregenereignissen ist nicht ausreichen. Von der Versiegelung der Oberflächen ist die Verdunstung in der Jahresbilanz stärker als die anderen Komponenten des Wasserkreislaufs betroffen. Trotzdem werden bisher bei der Planung neuer Baugebiete hauptsächlich der Oberflächenabfluss und in zunehmendem Maße die Versickerung untersucht. Die Reduzierung der Verdunstung wird zumeist vernachlässigt. Ursache für diese Reduzierung ist die fehlende Zwischenspeicherung des Wassers. Das wirkt sich direkt auf den Energiekreislauf aus, da die nicht für den Verdunstungsprozess benötigte Energie in den bodennahen Schichten bleibt. Im ersten Teil werden die Einflussfaktoren auf die Verdunstung erläutert und ein Überblick über die Berechnungsmethoden gegeben. Im zweiten Teil werden die Oberflächen unbebauter und bebauter Gebiete systematisiert und in Landnutzungsarten unterteilt. Für diese werden die hydrologischen und energetischen Eigenschaften und deren Auswirkungen auf den Wasser- und Energiehaushalt erläutert und die mittleren Jahresbilanzen berechnet. Die tatsächliche Verdunstung wird auf der Basis der Gras-Referenzverdunstung und der Landnutzungsart ermittelt. Ausgangswerte sind langjährige meteorologische Jahresmittelwerte. Die Verdunstung von Wasserflächen wird mit dem Temperaturgleichgewichtsverfahren berechnet. Mit den vorgestellten Verfahren können Einzugsgebiete von Bebauungsplangröße untersucht werden. Es werden Lösungen zur Beibehaltung eines möglichst hohen Verdunstungsanteils in bebauten Gebieten vorgeschlagen. Ansatzpunkt ist dabei stets die Zwi-schenspeicherung des Regenwassers. Am wirkungsvollsten sind dabei Dachbegrünungen, Wasserflächen und Bäume. Das Verfahren wird an zwei Beispielen angewandt - die Erschließung eines Industriegebietes auf einer vorher land- und forstwirtschaftlich genutzten Fläche in Treuen im Vogtland und der Neubau einer Untergrundstation im Zentrum der schwedischen Großstadt Malmö.
Evapotranspiration could be called the air-conditioner of the earth. It is connecting the water and the energy cycle. The components of the water and energy cycle are related to each other in a dynamic system. Urban development is interfering with this system. Changes of the water and energy balance resulting from construction can be calculated on the basis of long-standing annual average balances and compared with the balance in the catchment area before construction. Before granting building permission, the impacts on the water and energy balance should be evaluated in order to minimize interference with nature. Causing long-term impacts must be considered beforehand in planning. Coping only with design storm events does not suffice. Evaporation is more intensely affected by the paving of streets and squares and by constructing buildings then the other components of the water cycle. However, up to now, in the process of design and planning permission of new development areas, the focus is on runoff and, increasingly, on infiltration of rainwater. The large reduction of evaporation is mostly neglected. The reason for the reduction is the lack of buffer storage for water. Thus directly affects the energy cycle. Energy which is not used for evaporation remains in the near-ground layers. In the first part, the factors influencing evaporation are explained and an overview over the methods of calculation is given. In the second part all surfaces of urban and natural areas are systematized and subdivided into types of land use. The hydrological and energy properties as well as their effects on the water and energy balance are elucidated for this types of land use and their average annual balances are calculated. Solutions are presented for retaining in urban areas an evaporation rate as high as possible. Starting point hereby is always the buffer storage of rainwater. Most effective measures are the installation of rooftop greening, open water surfaces and trees. The calculations are performed on the basis of the FAO reference evaporation and the types of land use. Starting values are long-stand average annual meteorologic values. The evaporation of water surfaces is calculated with the temperature balance model. The method is applied to two examples showing the impacts of land use change on water and energy balance: the development of agricultural and forest land in Saxony into an industrial development site, and the impact of the construction of an underground station in the centre of the City Malmö, Sweden.

Syftet med arbetet är att få en förståelse för moss-sedumtakets bullerdämpande egenskaper. Jag kommer även att försöka förutsäga med hjälp av akustikteori vilken utav de två olika uppbyggnadssystemen av moss-sedumtak som ger den bästa bullerdämpande effekten.

Mätningarna kommer att bestå i att registrera ljudtrycksnivån i rummet, vid varje oktavband i frekvensområdet 125-4000 Hz. Först utan moss-sedummattan och sedan med moss-sedum mattan. Storleken på differensen i ljudnivån ger en bild av i vilket frekvensområde som ljudabsorptionen är effektivast. För att ytterliggare öka förståelsen för hur moss-sedum absorberar ljud så kommer även absorptionsfaktorn att beräknas. Utifrån resultaten kan man se en tydlig bild på hur xeroflor moss-sedum mattan absorberar i frekvenserna 125-4000 Hz. Den har sin bästa absorption i området 500-4000 Hz och i detta område så är det runt 1000 Hz som den absorberar effektivast.

 

Om vi tittar på de två olika systemen som Veg Tech använder för att bygga upp ett sedumtak på så sker dämpningen i XMS 0-4 med hjälp av luftspalten och i system XMS 2-27 i VT-filten. Men i detta fall så är luftspalten endast 25 mm så en märkbar ökad dämpning är svårt att föreställa sig. VT-filten som används i XMS 2-27 har öppna celler och kan liknas vid mineralull, som är en bra absorbent. Min slutsats är att 10 mm VT-filt ger bättre dämpning än en luftspalt på 25 mm.

 

The growing industry of Information and Communication Technology requires higher computing capacity of data centers/technical sites. The air conditioning in data centers is the key to assure a sustainable computing environment. However, the traditional cooling systems cost are responsible for large environmental footprints especially on energy consumption and greenhouse gas emissions. As a result, a green innovation of data center cooling solutions is taking place. The telecommunication company Teliasonera is developing a high density data center cooling system - the “Green Room” and has been studying the environmental performance of this system using a Life Cycle approach. As an extension of the previous study, more aspects of the project i.e. the location, life span, alternative cooling solutions, energy recovery possibilities and uncertainty analysis is explored by using Life Cycle Assessment (LCA) methodology. The comparison of the locations of the Green Room indicates that the local temperature and electricity production sources are essential factors for the environmental performance of the Green Room. The analysis of the Green Room’s life span reveals that the utilization phase may not always cause the most significant impact during the whole life cycle of the Green Room. If the life span changes, the manufacture phase may predominate the life cycle of the Green Room. The comparative result of alternative cooling technologies addresses that utilizing “natural coolant” (e.g. geo cooling) is a key for sustainable cooling innovation as it would significantly reduce the environmental footprint of the cooling system. Besides, heating a single building (partly) by the waste heat generated from the Green Room could save 30% of cumulative energy input and could reduce more than half of the total environmental impact. Additionally, results uncertainties caused by the choice of different LCIA methods are discussed in the end of the study.
The Teliasonera Green Room Concept for high and mid density of ICT equipment

Greenroofs are increasingly being recognized as an effective site level best management practice (BMP) to reduce the volume of stormwater runoff in urban environments. For some water quality constituents, greenroofs can improve runoff water quality but recent studies demonstrate greenroofs are sources rather than sinks of phosphorus (P). Accordingly, further research is required to evaluate treatment technologies that improve the performance of these BMPs. This study examined the use of two engineered media types to reduce phosphorus loadings from a greenroof located on the Archetype Sustainable House at Kortright in Vaughan, Ontario. A treatment system was installed to capture and remove P in stormwater runoff using sorptive properties of an engineered media. A mass balance approach was used to evaluate pre and post-treatment water quality. Pre and post-treatment water samples were collected for 25 rainfall events from July 11, 2009 to August 22, 2010 and analyzed for soluble reactive phosphorus (SRP), total phosphorus (TP), suspended solids (SS) and total dissolved solids (TDS). Storm events ranged in return frequencies from < 2 years to 35 year periods. The results show that the greenroof was a consistent source of P. The volume weighted mean concentrations were 0.769 mg/L and 0.630 mg/L for 2009 and 2010 events, respectively. The media used in 2009 reduced SRP loadings by 32.0% and TP loadings by 25.4%. The media evaluated in 2010, reduced SRP loadings by 82.4% and TP loadings by 86.6%. The greater P removal demonstrated by the 2010 media is attributed to a higher specific surface area and increased P sorptive capacity. Results of this study will help inform the use of sorptive materials in greenroof applications and a wider range of best management practices for stormwater quality treatment.

碩士
國立臺灣大學
園藝暨景觀學系
101
In response to the impact of global warming in twenty-first century, a roof cooling technique of building energy saving, which is the green roof. As the roof membrane structure, green roof can effectively reduce stormwater runoff, saving energy from air condition and provide basic ecological function. Either as a means of building energy saving or as a part of park and green space system, green roof plays a decisive role. Green roof develops for decades in the whole world, and now the industry of green roof in Taiwan is now began to sprout. But Taiwan is still in lack of study to investigate how to implement green roof in a systematic way. Therefore is the motivation of this study. Setting of green roofs involving land use zones and building types, consider the larger roof area and unified building type will be better condition for case study. The study chosen the industrial zone as the objective discussed, and Southern Taiwan Science Park(STSP) is the case study objective. Through the analysis of factory buildings, green roof whole-life cost analysis, and case analysis of green roof policy experiment of Berlin and Tokyo to propose the implementation strategies of green roof in STSP. The study use qualitative method, included interview, literature analysis and Case analysis. Research results have three, first, indicate that industrial plant comply the requirements of setting of green roof, but the roof space is limited. Second, current stage of the implementation of green roofs in STSP will influenced by the impact of extreme stormwater and has the problem in choosing plant materials. Third, implementing green roof policies in STSP should combine the green roof technical specifications into the land use regulation, and through the minimum greening rate, grants, tax reduction, and maintenance management examine as the main policy tool. Case of STSP provide us a positive imagination of green roof policy, and these technical specifications and incentives measures can be the frame of green roof design for those government agencies, experts and scholars. The Science Park is under the jurisdiction of the National Science Council, it’s the perfect objective to be the model case of implementation of green roof policy of central government. Suggested future research can move on to focus on local plant material research and environmental benefits.

博士
國立臺灣海洋大學
河海工程學系
104
In recent years, rapid urbanization has worsened the urban water environment with problems of urban flooding, drought, water pollution, exhaustion of groundwater, disappearance of biodiversity and landscape amenity, the health of living environment, and so forth. A lot of cities worldwide are seeking the solutions to encounter the negative impacts brought by urbanization. To ensure a better quality of life and achieve sustainable development, Low Impact Development (LID), Best Management Practice (BMP), Water Sensitivity Urban Design (WSUD), Sustainable Urban Drainage System (SUDS), and so forth have been widely implemented in most developed counties to address the issues mentioned above. These systems can be provided as a stand-alone system or in combination with centralized water systems. Elements in those systems normally have multiple-functional objects which include storm water mitigation, water retention, water quality improvement and landscape amenity. Many previous research results have pointed out that green roof can significantly improve the urban water environment. However, limited research in the areas of the hydrological performance, rainfall runoff relationship and combination of rainwater harvesting system with green roof, has been found locally. The results and approaches obtained by foreign research are not adaptable locally due to different climate and hydrological conditions. Therefore, the hydrological performance of green roof should be studied locally. Therefore, the purposes of this study focused on the following three topics: 1) analysis the hydrological characteristics of extensive green roof; 2) establish the hydrological model descripting the relationship between rainfall and runoff of extensive green roof; and 3) set up the methodology for determining the capacity of storage volume for rainwater harvesting system if designed with green roof for irrigation. The methodologies and findings for each topic will be descripted and explained in the followings sections. 1. For studying the hydrological characteristics of green roof, a physical model of extensive green roof had been set up at indoor with size of 100cm (L)*100cm (W)*40cm (H). Artificial rainfall simulator was set up having the rainfall intensity between 20-80mm/hr. Slope was adjustable ranging from 0 to 30 degree. Medium was made from peat soil, pearl stone and vermiculite with ratio of 2:1:1, respectively. Eremochloa ophiuroides was selected as the plant for the study. In the study, three variables were considered: rainfall intensity, medium thickness and slope of green roof. The results showed that green roof can effectively increase the time of beginning of runoff and time to peak flow, and reduce the volume of total runoff and peak flow. The runoff coefficient (Cpeak) for peak flow in the rational formula was reduced by 8.9 to 29.3% compared to that of non-green roof. Results also showed that green roof can increase the water retention capacity by 14.7 to 36.9%. The total runoff volume coefficient (Cvolume) varied between 0.66 and 0.85. In the study, the regression equation for predicting the total runoff volume was established based on rainfall and thickness of medium using statistical package of SPSS ver. 22. 2. To establish the hydrological rainfall-runoff model of green roof, a physical model of extensive green roof had been set up at outdoor with size of 200cm (L)*160cm (W)*40cm (H) and 20cm thickness of pottery stone as medium. The meteorological station had been set up with rainfall gage, thermometer, hygrometer, anemometer and solar radiation meter. Rainfall and runoff data from June 2013 to July 2014 were recorded and measured. Total number of rainfall reached 84. Based on the principle that rainfall depth exceeded 30mm and runoff duration less than 12hrs of rainfall selection, 10 rainfall events were selected for model calibration and verification. In the model, interception, initial moisture content, infiltration and drainage layer storage capacity were considered. The Green-Ampt equation was used for estimating the infiltration rate by using the Newton iterative method to solve nonlinear equation. The interception capacity and drainage layer storage capacity were measured on-site separately. From the sensitivity analysis, we found that initial moisture content was the most sensitive variable. Therefore, five rainfall events were used for the variable calibration. Through calibration, initial moisture content of 0.25 was found with minimum error. From the results of verification, average error reached 9.1% and peak flow reduced 26.4%, respectively. 3. For setting up the methodology for determining the capacity of storage volume for rainwater harvesting system designed with green roof for irrigation, a experimental set of green roof with size of 50cm (L)*50cm (W)*40cm (H) was placed at outdoor to measure the actual evapotranspiration by measuring the daily weight change. The evapotranspiration coefficient (K) of green roof could be estimated by comparing the actual measurement data and value obtained by the Penman-Monteith formula with data from the meteorological station. The inflow for the rainwater harvesting system was estimated by data obtained from the above sections. The storage capacity was determined by simulation model based on the mass balance. The optimal storage volume of rainwater harvesting system was then obtained by the theory of marginal physical product of potable-water replacement rate. Since green roof and rainwater harvesting systems were important elements in green building rating system. Hence, we tried to assess the impact of installing both elements to credit-earning in both rating systems of EEWH (Ecology, Energy, Waste, and Health) and LEED (Leadership in Energy and Environment Design) in Taiwan and US, respectively. From the viewpoint of the marginal credit cost, 50 to 75% of green roof coverage in the EEWH system was recommended and 100% for the LEED system.

Issues associated with urban development such as the urban heat island effect, loss of habitat, increased areas of impervious surfaces leading to storm water management concerns are well known. Many designers, engineers and policy creators are sensitive to these issues creating positive change by implementing alternatives to traditional development. Although, the concept of green roofs is not new to the prairies, modern development of this technology has not been fully embraced. Surrounded by concerns of efficacy and longevity here in the harsh northern prairie climate, green roof development and implementation has been slow. The objective of this practicum is to determine what green roof system and what vegetation of the short grass / fescue prairie and mix grass prairie would succeed in a green roof setting. Determining the appropriate planting palette and growth medium depth for the Canadian Prairies is essential for the development of the green roof industry locally.

Thesis (M.S.)--University of Georgia, 2005.
Directed by William Tollner. Includes articles submitted to The journal of hydrology, The international journal of heat and mass transfer, and Building and environment. Includes bibliographical references (leaves 79-82).

碩士
國立臺灣大學
園藝學研究所
92
Urbanization changes the water content balance in an urban area. The increasing number of impervious surfaces intercepts rain to infiltrate to soil. Therefore urban storm runoff occurs frequently and causes flash floods. In order to remedy the situation, many on-site storm water management methods received international attention. The so-called extensive greenroof is one of these storm water control technique. Extensive greenroof can assist in retaining rain on roof without occupying space on the ground, reducing runoff volume. The extensive greenroof is becoming more common in many parts of Europe and North America because of the high cost of land and high density of population in cities. In Taipei, land use is also dense and expensive. The use of this kind of eco-engineering is an economical way to improve the hydrology in the urban environment. This report further evaluates extensive greenroof. This study presents the storm water management of extensive greenroof with the Field Experiment method. First, according to literature review this study integrates hydrological theory, urban hydrology and storm water management theory, extensive greenroof reports, and relative experimentations for reference. The setup consists of 24 m2 of extensive greenroof samples on the roof. These extensive greenroof samples consist of two types of structure with three kinds of plants: The conventional type and G.R type of structure, and three kinds of plants called Callisia repens, Kalanchoe tubiflora, and Portulaca oleracea. Using the irrigation system, the plants are watered for 1 hour by a predetermined amount to simulate heavy rainfall in Taipei over a five-year period. Then by monitoring the hydrological performance on these samples, we can see that extensive greenroof affect runoff in three ways: 1.Delays runoff: runoff appeared after 20 to 25 minutes from the start of the simulated rain event; 2.Reduces peak runoff: the peak runoff from the samples was reduced from 10.3％ to 34.7％; 3.Reduces runoff volume: About 40 to 50 L/㎡ of storm water was retained in the greening system In addition, this study assesses the potential benefits of extensive greenroofs as a non-structural storm water management technique in Taipei. Results from analysis based on Taipei city records and roof configurations show that extensive greenroof strategy is most optimally applied to roofs in Taipei’s commercial areas where there exists 439ha of total roof area. If all the roofs are to use extensive greenroof, surface runoff will diminish by 13% when Taipei suffers five consecutive years of heavy rain.