Green Wedges Research Articles

Ecosystem service multifunctionality and trade-offs in English Green Belt peri-urban planning

Green Belt policies govern peri-urban landscapes globally by restricting built development. Yet, they often have little consideration for the land within them. This is especially the case in England where ecosystem services are poorly accounted for in Green Belt policy, whilst also being viewed as a development obstacle, with few environmental and social benefits; a situation mirrored in peri-urban landscapes globally. Moreover, there is a significant research gap into Green Belts through the socio-ecological lenses of ecosystem services and multifunctionality, which allows populist discourses to go unchallenged. Using modelling and participatory mapping data this paper addresses this gap by quantifying the ecosystem service supply, trade-offs and multifunctionality of the North-East Green Belt, and the wider planning and policy implications. The results show that contrary to claims, Green Belts in England can and do provide multiple benefits to people when studied through these lenses. However, levels of individual ecosystem services and overall multifunctionality differ spatially within Green Belts resulting in opportunity areas as well as potential losses of ecosystem services from development. Areas of deciduous and coniferous woodland as well as key “green wedges” close to urban populations were found to be multifunctionality “hots-spots”, whereas arable and improved grassland provide notable “cold-spots”. Trade-offs were mostly from provisioning services. We argue that Green Belt policies explicitly and holistically accounting for ecosystem services could catalyse a multifunctional opportunity space for climate, nature and people in peri-urban landscapes. Additionally, our study demonstrates the conceptual merits of ecosystem service multifunctionality for planning.

Assessment of land use change of ecological green wedge and cooling island effect: A case study of Wuhan, China.

The construction of urban ecological green wedges, which can mitigate the heat island effect through cooling and ventilation effects, is an important way to enhance the adaptation of cities to climate change. Dynamic monitoring and periodic assessment of both the conservation status and cooling effect of ecological green wedges is a key to ensure the heat mitigation benefits. Based on multi-source remote sensing data, we systematically analyzed the land use changes of six ecological green wedges in Wuhan in 2013 and 2020 using the methods of Markov transfer matrix, land use dynamics, and comprehensive index of land use degree, and evaluated the changes in surface temperature of the ecological green wedges and their cooling island effect. Results showed that the ecological green wedges in Wuhan generally had a large amount of construction land encroaching on ecological land from 2013 to 2020, with the water decreased the most. With the continuous deterioration of ecological green wedges, their land surface temperatures showed rising trends, together with significant weakening trends in cooling island effects. Among all the six wedges, the Dadonghu, Tangxun, and Wuhu exhibited relatively better ecological conservation, slighter land use change and lower overall development degree. Qinglinghu and Houguanhu demonstrated average levels of conservation. Fuhe experienced the most severe change under the significant influence of the westward policy of Wuhan City, with the proportion of water decreasing by 7.1%, warming up by 3.00 ℃, and the largest reduction in cooling distance for the cooling island effect, amounting to about 210 m. The results provided scientific evidence for the urban heat island mitigation-oriented planning and management of ecological green wedges for Wuhan City.

Delineating and Characterizing the Metropolitan Fringe Area of Shanghai—A Spatial Morphology Perspective

The metropolitan fringe area is of great significance to a city’s future growth. However, relatively little attention has been paid to delineating and characterizing the metropolitan fringe area from a spatial morphology perspective, which contributes to the planning and design of metropolitan fringe areas. Therefore, the aim of this study is to develop a morphology–based method to delineate the metropolitan fringe area and investigate the characteristics of its spatial morphology. Drawing upon a large–scale dataset on the spatial morphology of Shanghai, this study finds that the metropolitan fringe area is generally circular in shape and is dominated by residential, industrial, agricultural and forestry land. The metropolitan fringe area accounts for 24.65% of the total area of Shanghai and is mainly located between its outer ring and suburban ring areas. The distributions of spatial characteristics of the metropolitan fringe area suggest that the area has a relatively lower level in terms of building height, building density, and development intensity. Furthermore, the metropolitan fringe area of Shanghai contains five key spatial elements, including residential and industrial clusters, shadow spaces accompanying clusters, corridor lines, green wedges, and surfaces. The interaction of the five spatial elements lays the foundation for the prototype of the spatial structure of the metropolitan fringe area of Shanghai, which is of great significance to understanding the heterogeneity within the metropolitan fringe area in terms of the distribution of spatial morphological characteristics. Such heterogeneity also needs to be considered in the planning and design of the metropolitan fringe area.

Changing approaches to green infrastructure design: from modernism to the future: Warsaw case study

International modernism has brought new solutions to urban greenery, primarily aimed at improving the living conditions of the inhabitants. Currently, much more is expected of green areas, and at the same time, various impacts influence their modifications. The article focusses on changing approaches to the issue of green wedges design resulting from the socio-political transformation and the changes in approaches to city planning priorities. We selected Warsaw for detailed research, where the evolution of this approach can be clearly observed. The study showed the changes in the size, layout and function of one of the most important green areas and residents’ expectations. The formulated conclusions and threads may be helpful in spatial policy, spatial planning and urban design in various cities with an open areas structure similar to Warsaw.

Typologising site-specific features in young industrial landscapes

Young industrial landscapes (YILs), dating roughly from the 1930s to 1970s, are by virtue of their location, size, and partly underused capacity potential new locations for urban redevelopment driven by municipalities and private investors. However, such redevelopment often neglects existing physical characteristics including heritage and ecological potentials. This paper raises awareness and knowledge of these potentials by examining YILs’ spatial characteristics as part of the process of elaborating their future roles as sites for urban transformation. We develop a typo-morphological approach to analyse the physical structure of YILs in the Copenhagen capital area, revealing both general and site-specific qualities relevant for future transformations. We find that YILs’ locations and edge zones hold potential for mediating access between cities and green wedges. Site-specific scenic locations, significant earthworks, plantings, and buildings have potential for reuse and contribute spatial ambience. The paper finally discusses how typo-morphology might be understood from a YIL perspective.

Effects of multi-scale structure of blue-green space on urban forest carbon density: Beijing, China case study

Landscape structure influences the amount of carbon that can be stored in an ecosystem. Currently, majority of research have been focused on the responses of landscape structure and functional relationships to urbanization, and few have specifically focused on blue-green space. In this study, Beijing was used as a case study to explore the relationship among the blue-green spatial planning structure of green belts, green wedges and green ways, the landscape configuration of blue-green element and carbon storage of urban forest. The blue-green elements were classified using high-resolution remote sensing images (0.8 m) and the above-ground carbon storage estimations of urban forest based on 1307 field survey samples. The results show that green belts and green wedges have a higher coverage percentage of blue-green space and big blue-green patches than that of built-up areas. However, they have lower carbon density in urban forests. The shannon's diversity index of blue-green space was found to have a binary relationship with carbon density, in which, urban forests and water bodies were the key combination in increasing carbon density. The presence of water bodies in urban forests increases the carbon density to up to 1000 m. The effect of farmland and grassland on carbon density was found to be uncertain. With this, this study provides basis for sustainable planning and management of blue-green spaces.

Green Infrastructure Development for a Sustainable Urban Environment in Chittagong city, Bangladesh

The urban green belts mechanism was part of the city planning landscape of the 20th century for sustainable urban management. Greenbelt is a land-use policy and designation used in land use/land cover planning. The green belt has long been a design policy that also has a base in London accepted by other renowned cities such as Ottawa, Birmingham, Seoul, Frankfurt, Tehran's, Mashhad, Beijing, Gulbarga, Ontario, etc. Benefits include the value of living close to the green belts, recreational resources, productive farmland, transport connectivity, and a wide range of life support ecosystem services. The study investigated the present green space condition and its infrastructure with other cities around the world and prescribed the other mechanism in reviewing the Master Plan and the Detailed Area Plan of Chittagong city, Bangladesh along with a significant number of journal articles, books, and reports. The study found that the city of Chittagong is facing various problems in the present decades with its various problems like green space, recreational facilities, disaster, public health risk and so many. It also found that the city's geographical condition is suitable for developing an effective green belt in its periphery area. Although green wedges is another park system proposal for the barriers of urban green belt. The importance of land allocation for urban green space is usually neglected or easily reported in the city transition region. Besides, the city of Glasgow, Stockholm, Melbourne, and Copenhagen, etc. are accepted green wedges mechanisms. For some barriers as like as industrial development and some exclusive economic zone, some green wedges are much suitable in the gap of urban green belt in Chittagong city. The concept of green belt and green wedges both supports sustainable urban management in the city of Chittagong. However, these findings and analysis will be of great importance to the urban planners and decision-makers, for making environment-friendly sustainable future planning of modern and the planned Chittagong city.

Suitability of Urban Green Belt and Green Wedges in Chittagong City, Bangladesh: An Investigation into the Sustainable Urban Environment

Green belts and green wedges promote ecological balancing and hazard reduction in urban areas. The study attempted to identify suitable locations for urban green belts and green wedges in Chittagong city (CC). The mechanisms of the study were reviewing CC Master Plan, Detailed Area Plan (DAP), field observation, key informant interviews, and small groups discussions. Normalized Difference Vegetation Index was used for the vegetation classification from 1990 to 2021 at a 10-year interval. The urban built-up area of the Chittagong Development Authority (CDA) was 18.64 sq. km in 1990 while it became 139.74 in 2021. In 1990, dense vegetation was 153.21 Sq.km but it decreased to 19.39 Sq.km in 2021, because of rapid population growth and unplanned urbanization. A highly suitable site for the green belt was found in CDA coastal area. Besides, Kalurghat industrial zone, Chittagong Export Processing Zone, Nasirabad, and Baijid area were found appropriate for urban green wedges. Most suitable (83.60 sq. km) and moderately suitable (232.6032 sq. km) areas for the urban green belt were identified and in the coastal zone maximum suitable areas’ length was 57.61 km. The study concluded by urging for land-use zoning and the implementation of the urban green belt and green wedges, and raising voices against hill cutting by urban neighbourhood communities in CC.

Reconsidering green belts, green wedges and greenways

Facing accelerated urbanization and landscape alteration, cities expand on the territory showing better or worse relationships between built environment and green spaces. Based on recent literature review, this article discusses the green wedges, green belts and greenway planning models in order to evaluate their capability in answering contemporary ecological and social issues. The article presents a conceptual overview of the selected planning models through a recent literature review, looking at the fundamental concepts of green infrastructure; then, it enlightens the connections between the spatial forms and the functions derived of these forms. These three models are connected infrastructures, varying between the ring, the star or linear forms. What differs the most is the capacity to encompass existing patches like forests or other valuable areas and the proximity and distribution of green spaces throughout the city. Whilst green belts, for their fringe condition, distance itself from the majority of inner-city dwellers, both green wedges and greenways can cross the urban fabric, and reach a greater number of neighborhoods, although the simple existence of these features does not guarantee their social functions. These findings have significant implications for the design of city expansions and can help to configure better neighborhoods in growing cities.

Historical Development of Urban Green Infrastructure and Possibilities of its Implementation in the Republic of Croatia

Research has been motivated by a wide range of concepts of the term urban green infrastructure. As the aim was to indicate a clear basis for the term, an investigation of its development was a necessity, not only in the European, but also in a broader context. Although green infrastructure is included in the 21st century policies of protection and development of EU landscapes, its foundations can be traced back to the models of ideal Renaissance towns and urbanist concepts mainly from the 19th and 20th century. In these historical periods used concepts meant urban landscapes as systems, a part of the environment, as seen in green corridors, green belts, green wedges, green networks and through the perception of urban green systems. As a modern concept the urban green infrastructure has been upgraded with developed roles, extending functions, scopes and scales from previous historical models. In that sense it maintains its social role of improving the quality of life in towns, while at the same time defining town texture with its urban morphological significance. At the same time it also develops ecological values and extends its scale to nonurban local, regional and international contexts. Despite its benefits, spatial planning documents in the Republic of Croatia still lack measures and actions which would recognise the true benefit of green infrastructure in spatial development.

Urban green space optimization based on a climate health risk appraisal – A case study of Beijing city, China

Urban heat islands (UHI) and global climate change pose serious threats to human health, making health risk appraisal of urban space as well as the planning and improvement of green space important research projrcts. Meteorological sites, satellite images, electronic maps, questionnaire survey data, statistical yearbooks, ArcGIS spatial analysis technology, MATLAB matrix analysis technology, remote sensing inversion, and ground-object extraction technology were used in this study to evaluate how changes in Beijing’s urban thermal environment influence the health of residents. A genetic algorithm was used to optimize the simulation of green space, based on which, different measures were proposed to improve planning. The results show that areas of greater UHI impact on respiratory diseases, cardiovascular diseases and emotional health are mainly concentrated south of the North Second Ring Road in central Beijing. Furthermore, low-level influence areas are highly connected and clustered, while the high-level influence areas are distributed in clusters. The intelligent optimization and simulation of green space show that it exhibits a spatial distribution potentially with building green wedges and cooling corridors. Based on apprasial on health risk impact, analysis on health and climate zone, as well as optimization and simulation of green space, measures such as cooling nodes, urban blue axes, green rings, pergolas, and ventilation corridors are proposed to improve the comfort of urban living environments as well as reduce risks associated with health and environment.

Urban Green Space: Comparing the EU and Ukrainian Practice

The goal of the paper is to compare the urban green space practice in the EU and Ukraine to find the advantages and drawbacks of both approaches. In order to reach the goal, following tasks has been raised: (1) to reveal the most common patterns of green space allocation in European cities; (2) to consider the urban green landscape in Ukrainian first-tier and second-tier cities; (3) to compare the trends and challenges of urban green space allocation in the EU and Ukraine. In Europe, a typical pattern of green space is a combination of greenbelts, regional green areas, green wedges, green middles, green infrastructure, etc. The main significant feature and advantage of green areas in European cities is the connectivity of the larger objects (parks and woods) and smaller ones (squares, boulevards, inter-quarter plantings, etc.). Urban territories in Ukraine involves quite large green areas (mostly by combining "communal parks" and "green infrastructure"). Transformation crisis leads to the vast decline of industrial zones, which were spontaneously transformed into de-facto green or brown spaces. After economic recovery green space is shrinking dramatically under the pressure of commercial and residential zones. For Ukraine, the challenge is the creation of small urban landscaping facilities and increasing functional content and quality of the existing green spaces.

Flexible land-use and undefined governance: From threats to potentials in peri-urban landscape planning

Densification of cities is presently one of the dominating strategies for urbanization globally. However, how densification of cities is linked to processes in the peri-urban landscapes is rather unknown. The aim of this paper is to highlight the potentials in of peri-urban landscapes to be recognized as complementary providers of urban ecosystem services when green areas in cities are reduced by densification. We suggest that the way forward is to change the perceptions of peri-urban areas from being defined as located between cities and rural areas with a specific population density or a geographical distance, to become recognized as a landscape defined by its functionality. By identifying and describing the functionality in peri-urban landscapes the existing governance gaps can be recognized and thus dealt with through adaptation of existing planning tools. Although not yet articulated, peri-urban areas should be used to facilitate integration of top down and bottom up approaches and thereby closing the governance gaps. We illustrate this reasoning by two examples; one of the establishment of green wedges in Stockholm, Sweden, and the other with the establishments of international Model forests. We conclude that further densification of cities will create a lack of ecosystem services in cities by putting an even higher pressure on the peri-urban landscape and not as suggested today that densification lower pressure on peri-urban landscapes. Rethinking and reframing the peri-urban areas by adapting existing platforms will potentially contribute to a more nuanced discussion on strategies for urban development generally.

A socio-ecological perspective of urban green networks: the Stockholm case

Landscape fragmentation threatens habitats, biodiversity and other ecosystem services. In tackling this threat, the dynamic processes of social-ecological systems should be recognised and understood. Although network analysis based on graph theory has been recognised as an efficient way of spatially understanding landscape or habitat connectivity, only few studies have offered specific approaches or suggestions for integrating detailed social-ecological values into geographical distributions. As a contribution to bridging this gap, this paper introduces a social-ecological network model for the issue of landscape or habitat fragmentation applied to the case of Stockholm, Sweden. Graph theory was used in combination with sociotope and biotope maps for simple visualisation of network situations in two-dimensional maps. The European crested tit (Lophophanes cristatus), European common toad (Bufo bufo) and human beings were selected as indicator species, based on a landscape ecology analysis in Stockholm Municipality in 2009. Slope, land use and human disturbance maps were assessed in order to decide cost values of travelling from node to node. Lease-cost-path accumulation was used to create ideal reference maps of green networks. Three separate maps were then developed for suggesting efficient routes for three indicators in city scale that mainly connect from the Royal National City Park to the other parts of the city. The model in Hjorthagen neighbourhood to highlight two practical paths that link this fragmented community to its neighbouring park areas. Findings make it possible to address two scales of network improvement strategies, namely first for the city-scale green network that connects geographical habitats (nodes) and the regional green wedges of the city, and the second that of neighbourhood links between habitats in detailed layers of green networks. Strategic improvement potentials are presented based on ideal reference maps of green networks correspondingly.

Miradas innovadoras sobre la interfaz urbano-rural: el plan de Extensión de Ámsterdam, los planes del Condado de Londres y del Gran Londres, y el plan Dedos de Copenhague

The urban expansion develops in a rhythm and scale without precedents, becoming a topic of world scope with social, environmental and economic consequences. Currently it is difficult to establish a clear limit between urban and rural. The territories of urban rural interface (I-UR) have the value of being able to act as articulators between the rural and the urban system. As a result of this phenomenon, this article tries to establish a strategy to see how the I-UR space is planned. This is organized through the study of urban plans that raise an innovative urban - rural relation: The plan of expansion of Amsterdam, the County of London plan and the Greater London plan, and the Copenhagen plan. The work presents a topological look on these emblematic documents. In these plans, there are three types of solutions: The establishment of a space of I-UR framework where the rural soil is designed by the same precision as the urban one, a green belt that sets a limit to what is urban and a system of green wedges which penetrate into the city.

Accessibility and use of peri-urban green space for inner-city dwellers: A comparative study

Peri-urban landscape, space between the rural and urban setting, has generally been seen in planning practice as space in a transient state, likely to be developed in the future. However, research has shown that peri-urban green spaces have increasingly been used for recreational and leisure purposes by urban and rural dwellers.This study aims to explore whether, if urban dwellers' preferred green spaces are large peri-urban semi-natural areas, they will nonetheless be used only infrequently if the accessibility of these spaces is not swift.A questionnaire-based survey and focus groups were conducted to collect data from around 380 urban dwellers in two European cities of similar size but contrasting green space strategies, Ljubljana (green wedges strategy) and Edinburgh (green belt strategy). The results showed expected, strong cross-cultural preference for semi-natural landscapes (as opposed to formal parks and playing fields), such as woodlands, fields, waterways, etc. High appreciation and high use of green corridors was a more unexpected result. In addition, coastal landscapes appeared to be popular in Edinburgh and larger, peri-urban open spaces in Ljubljana. The frequency of visits to peri-urban spaces was considerably higher in Ljubljana, due to swift accessibility of the city's green wedges. In both cities, perceptions of distance to travel were the major barrier to frequent use of peri-urban green spaces. The findings suggest that green corridors enable enjoyable and easy access to semi-natural spaces in and around the city. This should be taken into account in future planning, as part of any wider green space strategies.

Abercrombie’s green-wedge vision for London: the County of London Plan 1943 and the Greater London Plan 1944

This paper analyses the role that the green wedges idea played in the main official reconstruction plans for London, the County of London Plan 1943 and the Greater London Plan 1944.1 Green wedges were theorised in the first decade of the twentieth century and discussed in multi-faceted ways up to the end of the Second World War. Despite having been prominent in many plans for London, they have been largely overlooked in planning history. This paper argues that green wedges were instrumental in these plans in the formulation of a more modern, sociable, healthier and greener peacetime London.

Role of green areas for space integration of Kraków’s Metropolitan Area

Abstract The Kraków Metropolitan Area (KOM) is a specific functional region comprising a big city that is the Kraków metropolis, together with its neighbouring complex of settlements with a variety of mutual interactions. The social and economic space requires multi-dimensional enhancement of its interrelations and partial rehabilitation of its developed areas; it constitutes, at the same time, a potential which strengthens the position of Kraków as a European city. A clear structure of the metropolitan area and its internal links through green seams provide the basis for functional and spatial integration of the metropolis. The greenery, comprised in larger natural structures such as river parks and green wedges, enhances the area’s polycentric concept. The shaping of the urban tissue of Kraków and its suburban zone by composing and building a network of open spaces is the basic criterion for developing a coherent metropolitan area with a sustainable structure. Many problems of the urban environment and its surroundings can be fully understood through their analyses in various scales. In order to better illustrate this complex system of interrelations, reference should be made in analyses to the macroregional scale then narrowing them to the regional scale, to ultimately go down to the metropolis. The issues covered in the paper concern open areas which should not be discussed without a broader spectrum because the notion of green areas is understood to mean primarily spaces which are networked and intertwined with the settlement structure. Some of them are clear, for instance the greenery which accompanies water courses, and easy to identify. Marshlands are mostly linearly continuous and this makes them coherent in their nature. Other green areas (apart from larger forest complexes) are not of essential significance for the integration of the metropolis. The example of Kraków shows that the KOM (1) has a big potential expressed through its natural environment in the form of green areas. The anthropopressure, however, is so high that open spaces are being absorbed by developments. It is riverside areas which have retained a clear structure of interrelations and they should be perceived as the future for the links in the metropolitan area.

Perception-Based Valuation of Landscape in the Area Around Lake Rusałka in Poznań, Poland

The paper presents studies concerning perception-based analysis of landscape by means of the valuation method developed by Kazimierz Wejchert. This method consists in the scoring of landscape interiors of a given space. Evaluation concerned a recreation area located in the city centre around one of the best known water reservoirs in the city of Poznań. The experiment comprised investigations conducted by students of 6 specialisation groups, the field of study Horticulture, and lasted for 6 months. In that period students evaluated individual interiors of the study area. The aim of the analyses was to indicate differences in the perception of recreational landscape depending on different factors (specialisation within the field of study, gender, weather) as well as to potentially develop design guidelines for the management of recreational areas within the green wedges in the city of Poznań. Statistical analysis of the collected data facilitated formulation of more specific conclusions. Marked differences were found in the perception of landscape, depending on gender of respondents. The most attractive site was the area located immediately at the lake, while the ecotone zone, transition zone between ecosystems, proved to be least attractive. Slight differences were also found in the perception of landscape within the investigated specialisations within the field of study.

Understanding Beijing’s Moving Urban Fringe through a Spatial Equilibrium Model

The growth of the main built-up area of Beijing is characterised by a pancake like expansion, from 100 km2 in 1950 to 1210 km in 2005 in successive waves. The approach to future urban expansion will require careful consideration, as economic, environmental and social conflicts at the urban fringe have intensified. Two successive greenbelts have been designated to contain expansion and engender more compact growth. However, the first greenbelt has not been achieved successfully and many areas designated as the second greenbelt is facing implementation challenges. This paper builds on existing research into greenbelt policy implementation and investigates the impacts of alternative urban growth boundary proposals under a systematic modelling framework. It reviews the theoretical insights into growth at the urban fringe, and puts forward a methodology that links development at the urban fringe to the functioning of the entire metropolitan area. It outlines six alternative development scenarios that encompass the existing planning proposals for the urban fringe: trend growth, densification, stringent greenbelt, loose greenbelt, hybrid controls, and green wedges. We use a prototypical spatial equilibrium model to quantify the performance of the development scenarios in terms of production costs, consumer welfare, wages, floorspace rents, and commuting times. The analyses suggest that the physical forms of fringe area development do significantly affect the economic performance of the whole municipality. Alternative proposals, including those that have rarely considered in the past, should be investigated carefully in this light, in conjunction with related studies on social and environmental impacts of urban fringe development. 2