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Green plot ratio: An ecological measure for architecture and urban planning
Abstract
Current research on sustainability of cities has favoured the implementation and conservation of greenery in the urban context. The benefits of plants are not just environmental but recreational, aesthetic and emotional. The full benefits of plants and the role they play in the ecology of cities remain to be mapped out but the general significance of plants appears to be uncontested. This paper proposes a new architectural and planning metric for greenery in cities and buildings. This new metric, the green plot ratio (GPR), is based on a common biological parameter called the leaf area index (LAI), which is defined as the single-side leaf area per unit ground area. The green plot ratio is simply the average LAI of the greenery on site and is presented as a ratio that is similar to the building plot ratio (BPR) currently in use in many cities to control maximum allowable built-up floor area in a building development. GPR allows more precise regulation of greenery on site without excluding a corresponding portion of the site from building development. It provides flexibility to the designer while simultaneously protecting the green quota in the design. This concept has been applied in a number of design competitions in which the author has collaborated with colleagues and various architectural practices. It has also been adopted as a planning requirement by the client authority for one of the competitions for which the author has entered. While seen as a fundamental and important metric, GPR is not in itself an indicator for all the ecological relationships between plants and cities. A larger set of related metrics need to be developed.
... A creative combination of building plot ratio and greenery, the concept of green plot ratio (GPR) was proposed by Boon Lay Ong in 2003. It refers to the average leaf area index (LAI) of greenery on a plot of land [13]. ...
... A creative combination of building plot ratio and greenery, the concept of green plot ratio (GPR) was proposed by Boon Lay Ong in 2003. It refers to the average leaf area index (LAI) of greenery on a plot of land [13]. The LAI is an important element to reflect the growth and ecological characteristics of plants, to study the function of the plant canopy, and to quantify the ecological capacity and exchange properties of the Earth [14,15]. ...
Street trees make up an important part of the eco-environment and landscape of urban roads. The species of street trees significantly affect the green volume of urban roads. The leaf area index (LAI) is often adopted to measure the ratio of green volume for urban roads, laying a scientific basis for optimizing street trees. This paper measures and analyses the LAI and green plot ratio (GPR) of 14 common street tree species in Xinxiang, a city in Central China’s Henan Province. The results show that, except for evergreens, the LAI values of deciduous trees varied significantly from month to month, forming a single-peaked curve. The LAI values of street trees have a significant positive correlation with the day of year (DOY) (P<0.01). As for the roads with a single row of street trees, the highest mean annual GPR values were achieved by Juglans regia Linn., followed in turn by Ligustrum lucidum Ait., Sophora japonica L., Populus tomentosa Carrière, Fraxinus chinensis Roxb. and Platanus orientalis Linn. Among the 12 common types of double-row road tree combinations, the GPR values all increased first and then decreased; the largest annual mean value belonged to the combination “Sophora japonica L.+ Sophora japonica L.” In the same section, the annual mean GPR value of double-row road trees was 3-7 times higher than that of single-row road trees. Our research demonstrates that the GPR can quantify the differences between different street tree species and combination types, and help to optimize the greening arrangement and plant configuration.
... According to Su et al. (2022), architectural design development was initiated in the 1960s. In 1920, projects like Le Corbusier's "computer for life" began receiving backing from engineers and architects who saw architecture as an objective definition to demonstrate creative expertise (Ong 2003). To illustrate this point, Stang and Hawthorne (2005) suggested "a conceptual framework for architectural design development. ...
The purpose of the study is to study the role of green financing in developing climate change supportive architectural design development to shift the modern world towards the idea of green architectural designs. Thus, the research estimated the nexus among green financing, green architectural development, and climate change mitigation by using the unit root analysis technique, co-integration analysis technique, bound-test estimates, auto-regressive distributive lag-error correction modeling (ARDL-ECM) technique to predict different short-run and long-run relationships, and robustness analysis technique. Following the previous study, modeling green financing index and green architectural design index are used to measure the variables. The findings of the study confirmed that green financing has significant role in supporting the climate change induction in architectural design development both in short run and long run. Moreover, green financing supports in promoting green architectural designs. By this, the viability of green financing in climate change that induces architecturally designed building is confirmed. Correspondingly, empirical results have shown that green financing contributes in climate change with 0.66, green infrastructure development with 0.72, and economic development with 0.31. While in long-run, green financing role in changing inside of climate of the architectural design is 0.74, supports in green infrastructure development with 0.67, and holds the 0.29 percent potential of contributing in economic development. These findings are robust with the 0.74 value of F-statistics, 1.89 value of t-statistics, and 110 value of Narayan standard estimate. In last, the study suggested way forward for stakeholders to promote green architectural designs to achieve SDG 8, SDG 11, and SDG 13.
... Green spaces in the urban environment reduce the temperature amplitudes, which improves the thermal comfort; take large amounts of rainwater, reducing the risk of flooding; reduce air pollution levels and increase the amount of oxygen; and have a beneficial effect on the psycho-physical condition of the people, and hence the disease is reduced. (Ong, 2002). ...
... However, it does not reflect the quality of the green structure, nor does it represent the variety of ecosystem services of the green space. In addition, the indicator of the green plot ratio can provide an effective method so as to assess the quality of greening in urban planning [14]. Both indicators can help urban planning policies to achieve more sustainable development [15]. ...
Digital technologies and public policies are fundamental for cities in defining their urban greening strategies, and the main goal of this research is to identify the applied digital technologies and the public policy dimensions implemented at the national level by the member states to promote urban greening in the literature and official documents. The methodology used is a systematic literature review (based on international studies), a Delphi study with experts, and a policy analysis, aiming to understand how the Portuguese government has implemented policies and identify the main technologies applied to urban greening. The main findings regard (i) the focus on the interaction between actors in policymaking; (ii) interpretive approaches used to examine the application of technologies in urban greening problems; and (iii) how policies reflect the social construction of ‘problems’. The research focuses on how policy analysis provides a powerful tool that can be used to understand the technologies, actions, interests, and political contexts underpinning policy decisions. The main lessons learned from this research are that urban greening can benefit urban centers together with the non-urban environment on which they have a functional impact, such as agricultural hinterland areas, forest spaces around the cities, and the rural–urban interfaces. Initiatives for urban greening are designed to enhance cross-border coordination, complementarities, flexibility, productivity, and access to the main international markets and territories.
The alarming rate of urban migration with ever-increasing demand for space has put tremendous strain on resources and has led to the exponential horizontal sprawl and the emergence of polycentric and vertical expansion of cities. Cities have sought to intensify urban centers with the high-density vertical city model, particularly in Asia. It is argued that segregation of pedestrian and vehicular traffic, and connectivity with transit hubs has led to the adoption of multilevel pedestrian networks and the more recent vertical stratification of urban streets and squares. Large-scale hybrid transit-oriented developments (TODs) concentrated around multimodal transit nodes are frequently characterized by sprinkling of familiar grade level elements (streets, squares, and green areas) throughout the project’s verticality. Complementing public spaces on ground, they take the form of roof top sky-gardens/sky-terraces/sky-bridges, to intermediate sky courts and sky bridges and underground public spaces. Such spaces have reinstated walking in cities such as Hong Kong, Singapore, and Bangkok. Drawing upon relevant literature and three specific case studies in Singapore, this chapter focusses on the critical role transit-led, stratified public spaces may play in shaping vertical urbanism going forwards. The case study findings are in part based on research undertaken by students at the Department of Architecture at the National University of Singapore (NUS).
Centra handlowe stanowią stosunkowo nowy element przestrzeni polskich miast, który wpływa na kształtowanie tkanki urbanistycznej. Problemem badawczym niniejszego artykułu jest ustalenie, w jaki sposób są zagospodarowywane tereny krakowskich centrów handlowych i jakie przyjmuje się w dokumentach planistycznych wartości podstawowych wskaźników urbanistycznych dla tych terenów. Przedmiot badań stanowią obszary wszystkich centrów handlowych zlokalizowanych w Krakowie. Celem jest określenie tendencji w sposobie ich zagospodarowania na tle obowiązujących dokumentów planistycznych. W pierwszej kolejności w oparciu o analizy GIS obliczono wartości 3 parametrów: wskaźnika powierzchni zabudowy, wskaźnika intensywności zabudowy i wskaźnika terenu biologicznie czynnego. Następnie zestawiono je z wartościami przyjmowanymi w miejscowych planach zagospodarowania przestrzennego. Z przeprowadzonych badań wynika, że budynki centrów handlowych w Krakowie zajmują średnio mniej niż 50% powierzchni terenu inwestycji. Tylko niewielka część działki jest zagospodarowana w formie zieleni (średnio 14,92%). W dokumentach planistycznych wartości wskaźnika intensywności zabudowy często dopuszczają powstanie inwestycji o bardzo zróżnicowanej kubaturze.
Die Bau- und Stadtplanungsbranche spielt eine wichtige Rolle für die nachhaltige Entwicklung der Gesellschaft. Unter dem Druck des globalen Klimawandels muss sich die Stadtplanung auf klimaneutrale Abläufe einstellen. Insbesondere für Regionen, die sich im Übergang befinden, sind Klimaneutralität und Strukturwandel Prozesse, die sich gegenseitig verstärken.
Es gibt bereits zahlreiche Forschungsarbeiten zum Thema Klimaneutralität, die sich mit Trends in der Stadtentwicklung, quantitativen parametrischen Analysen sowie der Entwicklung und Anwendung von Technologien und Strategien befassen. Aber wird jedoch noch kein klares und vollständiges System entwickelt, das die theoretische Ermittlung mit den Entwurfsmethoden verbindet. In dieser Masterarbeit wird durch umfangreiche Literaturrecherche ein theoretischer Rahmen geschaffen, der die bestehende einschlägige quantitative Forschung, Strategieforschung und Stadtentwicklungstrends integriert. Auf dieser Grundlage wird ein neues Städtebaus Modell entwickelt.
Im aktuellen Kontext der Klimaneutralität muss den Städtebau ein Gleichgewicht zwischen Umweltfreundlichkeit und Raumkomfort herstellen. Klima-adaptives Design ist dabei der wichtigste Ansatzpunkt. Es ist ein zusammengesetztes Konzept, das Klimaforschung und Entwurf integriert. Sie ist ein weitverbreitetes Phänomen in der Entwicklung der menschlichen Gesellschaft. Auf der Grundlage des Konzepts des klima-adaptiven Designs befasst sich diese Masterarbeit mit den nachhaltigen Anforderungen an den Städtebau im Zusammenhang mit der Klimaneutralität.
Die Studie besteht aus fünf Teilen.
- Überprüfung klima-adaptive Designansätze und der Notwendigkeit von Klimaneutralität.
- Einrichtung eines quantitativen Bewertungssystems durch die Untersuchung relevanter
Indikatoren.
- Überprüfung der Zugänglichkeit von Technologiestrategien.
- Bewertung der typischen Stadtraumtypen und Entwickelung der Strategien.
- Anpassung des Städtebaus basierend auf Bewertungen.
Die qualitativen und quantitativen Ergebnisse der Arbeit sind in die Optimierung städtebaulicher Lösungen für das Projekt Innovationsquartier Düren eingeflossen.
It is well known that urbanisation has many deleterious ecological effects. These may be mitigated by good urban design but the first step in doing this is to quantify them. This paper describes four simple ecological performance indicators which quantify the effects of urbanisation on surface temperature, hydrology, carbon storage and sequestration, and biodiversity. They have been developed and customised from recent studies, are simple to use, and require a minimum of input information; the only major inputs needed are the percentages of the different surface covers.The indicators were tested by applying them to four urban areas of Merseyside, UK, of contrasting affluence. The results showed that the greatest influence on ecological performance was the percentage of greenspace, particularly of trees. The affluent areas had lower temperatures, less run-off, more stored carbon, and higher diversity, largely because they had more open area and woodland cover. These results suggest that the indicators could be a useful planning tool, facilitating the comparison of existing urban areas, and helping to predict the ecological impact of new developments. However, the indicators also suggest that compact cities with good regional performance will inevitably have poorer performance locally, because of a lack of greenspace. The performance indicators could determine the potential of possible means of amelioration such as the use of roof gardens or permeable paving.
A primary objective of the Earth Observing System (EOS) is to develop and validate algorithms to estimate leaf area index (L), fraction of absorbed photosynthetically active radiation (fAPAR), and net primary production (NPP) from remotely sensed products. These three products are important because they relate to or are components of the metabolism of the biosphere and can be determined for terrestrial ecosystems from satellite-borne sensors. The importance of these products in the EOS program necessitates the need to use standard methods to obtain accurate ground truth estimates of L, fAPAR, and NPP that are correlated to satellite-derived estimates. The objective of this article is to review direct and indirect methods used to estimate L, fAPAR, and NPP in terrestrial ecosystems. Direct estimates of L, biomass, and NPP can be obtained by harvesting individual plants, developing allometric equations, and applying these equations to all individuals in the stand. Using non-site-specific allometric equations to estimate L and foliage production can cause large errors because carbon allocation to foliage is influenced by numerous environmental and ecological factors. All of the optical instruments that indirectly estimate L actually estimate “effective” leaf area index (LE) and underestimate L when foliage in the canopy is nonrandomly distributed (i.e., clumped). We discuss several methods, ranging from simple to complex in terms of data needs, that can be used to correct estimates of L when foliage is clumped. Direct estimates of above-ground and below-ground net primary production (NPPA and NPPB, respectively) are laborious, expensive and can only be carried out for small plots, yet there is a great need to obtain global estimates of NPP. Process models, driven by remotely sensed input parameters, are useful tools to examine the influence of global change on the metabolism of terrestrial ecosystems, but an incomplete understanding of carbon allocation continues to hamper development of more accurate NPP models. We summarize carbon allocation patterns for major terrestrial biomes and discuss emerging allocation patterns that can be incorporated into global NPP models. One common process model, light use efficiency or epsilon model, uses remotely sensed fAPAR, light use efficiency (LUE) and carbon allocation coefficients, and other meteorological data to estimates NPP. Such models require reliable estimates of LUE. We summarize the literature and provide LUE coefficients for the major biomes, being careful to correct for inconsistencies in radiation, dry matter and carbon allocation units.
Trees benefit urban communities environmentally, esthetically and recreationally. This raises the question of whether Denmark’s towns have enough space for more trees. A research project investigated this by examining in detail the potential for more sustainable planning and management of urban green space in towns with 10,000–40,000 inhabitants and was completed in 1999. The paper describes the vegetation cover in selected urban areas, including the cover of woody vegetation (trees and shrubs) and discusses the land area potentially available for supplementary planting in urban zones. The method used to map urban vegetation is discussed and related to Denmark’s administrative practice and planning system. Case studies are presented for various categories of urban land use to highlight the variation in vegetation cover and to identify the land area available for increasing tree cover. Apart from undeveloped urban land, the largest areas potentially available for planting included industrial zones, institutional zones and apartment complexes. Other types of residential district lacked the coherent space normally required for sustainable planting. The cover of trees and shrubs in the case study towns is very limited, but large areas of non-functional lawn could be available for planting. Lawn comprised the largest proportion of the urban surface cover in the case studies. The findings of the case studies were assembled into data sets relating to each type of urban zone and summed up in green structure maps based on geographical information systems. This approach can provide an overview of best practices to allow areas lacking vegetation cover to be identified. This assessment method can usefully be applied to incorporate issues related to the urban natural environment and urban greening potential into conventional planning practice in Denmark’s municipalities.
The light attenuation characteristics of tree crowns in leaf were independently measured by a photographic and a photometric method. Based on data collected from trees in full leaf, no significant difference was found between the two methods. This suggests that (contrary to the assumptions of some previous workers) photographic methods of measuring light attenuation can be applied to tree crowns in leaf. This is important as photographic methods allow much larger sample sizes than photometric methods.
Using examples from tropical systems, the author describes the ecology of natural systems in the first part of the book and human ecology in the second. Part I examines energy flows; atmospheric and edaphic nutrient cycling; population ecology of single species; interactions between populations of different species; ecology and evolution (including examination of coevolution, herbivory, pollination, mutualisms and mimicry); community ecology (emphasising various aspects of diversity, island biogeography theory, and stabilitiy); and patterns in time and space within tropical terrestrial biomes (forest, savanna, desert). Part II includes comment on human food systems; population structure and growth; human diseases; conservation of genetic resources; deforestation; desertification; and selection, conservation and management of nature reserves. Appendices are on: calculation of the intrinsic rate of natural increase (r) from life table data; introduction to mathematical models of interspecific interactions; indices of species diversity; and computation of doubling time from exponential growth rates. -P.J.Jarvis
We compared the accuracy of five methods used to estimate leaf area index (LAI) of eight open-grown deciduous trees, including six white mulberries (Moms alba) and two black cherries (Prunus serotina var. rufula). The methods included the use of four instruments (AccuPAR Ceptometer, CI-100 Plant Canopy Analyzer, image processing with the AgVision System, LI-COR LAI-2000 Plant Canopy Analyzer) and the application of a logarithmic regression equation. The image processing method demonstrated the highest probability of accurately estimating LAI (P = 0.99). However, all methods showed bias toward returning LAI estimates that did not increase as actual LAI increased when the mulberry tree data were examined separately from the cherry data. Additional research is necessary to determine whether this bias is real or merely a function of the limited sample size.
Vegetation in the Phoenix, Arizona, metropolitan area was surveyed using a modified stratified random sampling design to identify plant species and to measure foliar volumes for species-specific calculation of leaf mass. We identified the genus and species and measured the crown dimensions of plants located in a park and parking lot, and in three types of urban landscapes: flood-irrigated, mesic and xeric. Species compositions of these landscape types were compared quantitatively using a Sorenson index of similarity and the landscape types were found to be dissimilar. The three landscape types varied in calculated leaf masses and the respective identities of the dominant species, and relatively few plant species accounted for the majority of the leaf mass. Plant species and leaf mass data were used to estimate relative contributions from each landscape type of the biogenic volatile organic compounds isoprene and monoterpenes. Results from this study have implications for future plant surveys taken for biogenic emissions inventory development, and for plant species selection for urban landscapes, especially large-scale tree planting programs.