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CHAP TER 4.3
The Urban Landscape as a Social-Ecological System for Governance of Ecosystem Services Christine Alfsen, Ashley Duval, and Thomas Elmqvist
4.3.1 Introduction The constantly evolving urban landscape is a complex mosaic of human modifications, metabolic flows, networks, and built structures (e.g. Alberti et al. 2003). As emphasized by, for example, McDonald and Marcotullio (Chapter 4.1) and in many other chapters, the understanding of how urban ecosystems work, how they change, and what limits their performance, can add to the understanding of ecosystem change and governance in general in an ever more human-dominated world (Pickett et al. 1997; Elmqvist et al. 2008). Today, cities are facing enormous challenges, such as climate change and transformation to a future beyond fossil fuels. Ecosystems may play an important role in facilitating this transformation. Ecosystems provide flexibility in urban landscapes and help build adaptive capacity to cope with problems such as increased risk of heat waves and flooding. Urban ecosystems generate ecosystem services, many of which are crucial for the well-being of urban citizens (e.g. Elmqvist et al. 2008). In this context we argue for the necessity to view urban landscapes as truly interconnected social, cultural, and ecological systems and to recognize, map, and sustain ecosystem services within urban regions. There have been various approaches during the last two decades at the global scale, recognizing that ecosystem management and conservation strategies must be connected to human well-being. These include the Ecosystem Approach of the Convention on Biological Diversity (CBD 2000–08), a strategy for
the integrated management of land, water, and living resources that promotes conservation and sustainable use in an equitable way. Further, the UNESCO Seville Strategy (UNESCO 1996) explicitly recognizes connections between cultural and biological diversity and their role in sustainable development. The ecosystem approach, although acknowledging that the cultural diversity of humans comprises an integral component of many ecosystems, was originally meant to enhance communities’ ownership of conservation strategies in areas defined as ‘natural’. Hence, the ecosystem approach, while integrating the sectors/disciplines needed to manage the landscapes, was not intended to be applied to complex and fast transforming urban systems. Conceived as it was before the threats associated with climate change had reached public consciousness; it did not make the link explicit between ecosystem functions and human security and well-being. Today, with increased incidence of natural disasters and the looming threats associated with climate change, we have a much deeper sense of the immediate and inextricable connection between human security, well-being, and functioning ecosystems (MA 2005a). However, our current approaches to governance, resource allocation, and public information have yet to adapt in response to these threats. This chapter focuses on the challenges of combining our theoretical understanding of ecosystems with perspectives on alternative governance systems based on the ecosystem approach in humandominated landscapes. On a human-dominated planet, environmental solutions increasingly have 213
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to rely on innovative applications of science and technology rather than on strict nature preservation methods. We argue that the urban landscape is the right place to begin developing new forms of governance based on integrated and cross-sectoral responses to global challenges. Urban regions have the advantage of having concentrated scientific, technological, and financial resources needed for innovations (Redman, Chapter 4.2) and a potential capacity to mobilize resources, people, and governments at all levels to build social-ecological resilience through adaptive and strategic planning.
4.3.2 Urban ecosystems and ecosystem services A city is, among other things, a physical and social mechanism for acquiring and delivering ecosystem services to a dense human population (Lee 2006). The Millennium Ecosystem Assessment (MA) (2005a) found that 60 per cent of ecosystem services assessed globally are either degraded or being used unsustainably. Seventy per cent of the regulating and cultural services evaluated in the assessment are in decline. However, in MA, urban areas were largely left out even though urban ecosystems contribute to several environmental regulation services and cultural services of importance for human well-being (Bolund & Hunhammar 1999). In general, the urban landscapes present novel ecological conditions, such as rapid rate of change, chronic disturbances, and complex interactions between patterns and processes. Firstly, compared with ecosystems in rural areas, urban systems are highly patchy and the spatial patch structure is characterized by a high degree of isolation. Second, disturbances such as fire and flooding are suppressed in urban areas, and human-induced disturbances are more prevalent as well as intense human management of urban habitats. Third, because of the ‘heat-island’ effect, that is, higher mean temperatures in cities than in the surroundings, cities in temperate climates have significantly longer vegetation growth periods. Fourth, ecological successions are altered, suppressed, or truncated in urban green areas, and the diversity and structure of communities of plants and animals may show fundamental differences from those of non-urban areas.
Furthermore, cities are the most important points of introduction of exotic species. Although cities may sometimes be species rich, having higher species diversity than surrounding natural habitats, this is often due to a high influx of non-native species and formation of new communities of plants and animals. To what extent exotic species contribute to reduced or enhanced flow of ecosystem services is virtually unknown for any urban area, but since introduced species make up a large proportion of the urban biota, it is important to know not only to what extent introduced species are detrimental, but also to what degree some of the introduced species may enhance local diversity and maintain important functional roles. The potential for generation of ecosystem services in urban areas is often substantial (e.g. Pickett et al. 2008), albeit not very often realized. For example, urban parks and vegetation reduce the urban heat island effect and there is an important potential for lowering urban temperatures when the building envelope is covered with vegetation, such as green roofs and green walls, with the largest effect in a hot and dry climate (Alexandri & Jones 2008). In relation to overall climate change mitigation, urban ecosystems may assimilate large quantities of carbon, for example, in Stockholm County, ecosystems assimilate about 41 per cent of the CO2 generated by traffic and about 17 per cent of total anthropogenic CO2 (Jansson & Nohrstedt 2001), and residential trees in the continental United States could sequester 20 to 40 teragrams of carbon per year (Jenkins & Riemann 2003). Vegetation may reduce noise levels, and dense shrubs (at least 5 m) wide can reduce noise levels by 2 dB(A), while a 50-metre wide plantation can lower noise levels by 3–6 dB(A) (Bolund & Hunhammar 1999). Evergreen trees are preferred because they contribute to noise reduction year round (Ozer et al. 2008). There are also direct health benefits of green areas, vegetation and trees, for example, in a study from New York, presence of street trees was associated with a significantly lower prevalence of early childhood asthma (Lovasi et al. 2008). Green area accessibility has also been strongly linked to reduced obesity (e.g. Ellaway et al. 2007). In a review by Bird (2007), links were noted between access to greenspaces and a large number of health indicators, such
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as coping with anxiety and stress, treatment for children with poor self-discipline, hyperactivity and Attention Deficit Hyperactivity Disorder (ADHD), benefitting elderly care and treatment for dementia, concentration ability in children and office workers, healthy cognitive development of children, strategies to reduce crime and aggression, strengthened communities, and increased sense of well-being and mental health (see also Tzoulas and Greening, Chapter 5.2). The distribution and accessibility of greenspace for different socio-economic groups, however, often reveals large inequities in cities (e.g. Pickett et al. 2008), contributing to inequity in health among socio-economic groups, although confounding effects are not always possible to separate (Bird 2007). To what extent biodiversity and variation in species composition plays a role in the generation of environmental quality services is still poorly investigated (Elmqvist et al. 2008). For air quality, filtering capacity increases with leaf area, and is thus higher for trees than for bushes or grassland (Givoni 1991). Coniferous trees have a larger filtering capacity than trees with deciduous leaves (Givoni 1991). In the urban core there are probably fewer species and often very different species involved in the generation of ecosystem services than in more rural areas. Interestingly, the number of plant species in urban areas often correlates with human population size, and diversity may correlate with measures of economic wealth as shown, for example, in Phoenix, USA (Kinzig et al. 2005). Cultural ecosystem services refer to the aesthetic, spiritual, psychological, and other benefits that humans obtain from contact with ecosystems. Such contact need not be direct, as illustrated by the popularity of the virtual experience of distant ecosystems. Nor need such contact be with wild or exotic nature, as shown by the ubiquity of urban gardens, for example (Butler & Oluoch-Kosura 2006). Many cultural services are associated with urban areas and there is good evidence that biodiversity in urban areas plays a positive role in enhancing human well-being. For example, Fuller et al. (2007) have shown that the psychological benefits of greenspace increase with biodiversity, whereas a green view from a window increases job satisfaction and reduces job stress (Lee et al. 2009). This may have a strongly positive effect on economic productivity
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and hence regional prosperity. Several studies have shown an increased value of properties (as measured by hedonic pricing) with proximity to green areas (Tyrväinen 1997; Cho et al. 2008). As the urban landscape grows in both area and population, it is increasingly becoming the landscape of greatest familiarity to current and future generations. It will likely become a landscape of increasing interest and investigation amongst scientists, academics, citizens, and governments. Urban nature is often the most visible and easily accessible component of this landscape and may reflect city planning, as in the case of metropolitan parks, greenways, wildlife corridors, and botanical gardens. However, just as often, urban nature represents the practical and spiritual needs of urban residents wherever it occurs in the cramped home and rooftop gardens, community gardens, and unchecked regeneration in abandoned lots. In both a historic and contemporary sense, the urban landscape exists as an open book, subject to the contributions and modifications imposed by all generations and demographic groups of different ethnic, cultural, and socio-economic origins. As such, manifestations of the natural landscape within cities are subject to constant change, as are the narratives and values affixed to them.
4.3.3 Governance of urban ecosystems While different cities in different regions of the world face many of the same environmental challenges in light of growing populations (McDonald and Marcotullio, Chapter 4.1), the capacity to govern and respond to challenges attached to such fast transformations varies drastically. In trying to understand these differences, some classifications have been attempted, such as the one conceived by the United Nations University which conceptualizes world cities as belonging to three different groups; least developed, rapidly developing, and developed (UNU-IAS 2003). Least developed cities have been defined as those which have experienced few benefits from globalization flows, although they are rapidly urbanizing. The ability to expand and modernize their infrastructure is impaired by socio-economic inequalities, often accompanied by severe environmental degradation (UNU-IAS 2003). Rapid
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urbanization has proceeded in the absence of accompanying economic growth, resulting in widespread poverty. Lagos, Nigeria is one of the emerging global mega-cities of the South, with a population expecting to reach 17 million by the year 2015 (UN Department of Economic and Social Affairs 2004). Rapidly developing cities have often had growth facilitated by investment from public and private sources as well as far-sighted policies from their national government. Often, successes in these cities have come with heavy environmental repercussions. Technical and socio-economic changes occur so rapidly that these cities are ill-equipped to address the simultaneous issues of public health, equity, and environmental burdens that arise. This can be illustrated with the example of the increasing health and environmental costs of transportation in Asia, where now substantially more new cars are sold than in North America and Western Europe combined (UNU/IAS 2003). Developed cities in rich countries deal with a specific set of environmental issues, often related to urban encroachment upon rural areas of agricultural and forest land. The sprawling growth at the margins of urban centres is a major contributor to greenhouse gas emissions as household numbers increase despite decreasing household size, and cars are increasingly relied upon to connect people to the city centres where they often work. While such typologies have helped in differentiating between cities, and have helped caution against generalization of management models, they still do not reflect the degree of complexity required to manage linked social cultural and ecological systems at a variety of scales. It could be argued that some cities in rich countries, such as New Orleans and even New York City, still exhibit in some neighbourhoods, deep socio-economic inequities which are an obstacle to sustainable urban planning. Some rapidly developing cities, such as Shanghai, while being major contributors to greenhouse gas emissions, also are pioneering urban designs for carbon neutral development and energy saving measures at the frontier of science and technology. Some rich countries also have to contend with failed urban settlements and the
problems associated with depopulation, as witnessed in some parts of the United States in the wake of the financial crisis. These cases illuminate the necessity to address the needs of the population within urban areas through environmental services. Cities are at different stages in this process depending on their conceptual foundations and development status. In Chicago, for example, the origin of such an approach can be traced to far-sighted planners who at, the turn of the twentieth century, established a system of forest preserves in and around the Chicago Metropolitan regions. This greatly facilitated the establishment of Chicago Wilderness, which now includes Chicago metropolitan region and captures an array of rare ecosystems including tall grasses prairies, oak woodlands, oak savannahs, sedge meadows, marshes, bogs, fens, and other prairie wetlands. Through the dedication of an informed critical mass of people, the use of efficient science in policy bridging tools such as the Chicago Atlas of Biodiversity, and massive communication efforts, Chicago Wilderness succeeded in having citizens, policy-makers, and private land owners realize the existence and value of such ecosystems and having the Chicago Wilderness Biodiversity Recovery Plan integrated into regional development plans (Moskovits et al. 2004). Urban nature has different meanings for different people, a central consideration in the implementation of an urban planning approach based on connected social and ecological systems. In cities of the developing world, urban nature is particularly valued as a source of food, livelihood, fuel, medicine, and spiritual fulfilment. Thus, in dealing with the urban landscape, there may be important factors that are not traditionally regarded as scientific in nature and yet need to be recognized, valued, and incorporated in urban planning. For example, in the city of Salvador, in North-eastern Brazil, contemporary cultural practices with strong roots in African tradition have led to the development of a pharmacoepia of herbs that have been documented to treat a total of 156 diseases (Voeks 1997), and are not only accessible remedies for the urban poor, but are also now being sold as teas in upscale Brazilian supermarkets (Kanth 1999). If we are serious about adopting an approach that combines urban planning with healthy ecosystems,
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it is therefore necessary to start a conversation about urban ecosystem governance with all this diversity among cities in mind.
4.3.3.1 Global initiatives for improving urban ecosystem governance Spurred into action by local movements, a number of global and international initiatives are starting to merge, linking municipalities around nature conservation goals. Reports increasingly illustrate efforts, investments, and challenges of local authorities in assuming a more proactive role to ensure a safe, prosperous, and healthy future for their citizens and natural resources. The ICLEI LAB initiative, begun in 2006, gathers 21 cities that have, at different scales and in different ways, operationalized nature conservation into municipal programmes. Some have taken steps to conserve biodiversity at the municipal level, such as Curitiba, and have in the process acquired the status of ‘model cities’. Others have acknowledged that biological diversity conservation must take place at the regional level (e.g. Ile de France) and have strived to bring together the many jurisdictions and stakeholders concerned in regional development. Another global initiative, the UNESCO URBIS Initiative promotes science and knowledge for sustainability and resilience, education for empowerment and change, and land-use planning for mediation and conflict resolution in the urban landscape. The UNESCO URBIS Initiative draws upon the pioneering ‘Biosphere Reserve concept’ defined in the 1995 Seville Strategy, and the ecosystem approach defined by the CBD, to promote the interdependent goals of biodiversity conservation, sustainable use, and equitable access. The UNESCO URBIS seeks to contribute to an increased understanding, valuing, and reconnection of people and ecosystems in the urban landscape to: 1) Increase the resilience of urban socialecological systems. Ecosystems such as wetlands and coastal areas may provide a buffer against natural disasters such as floods and hurricanes. But for this to be effective, the
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population must be made aware of these natural functions and learn to incorporate nature in their daily life, even in heavily urbanized areas. In New Orleans, it is now quite widely recognized that the human tragedies caused by Hurricane Katrina constituted a manmade rather than natural disaster. Social and economic fragmentation and lack of preparedness played a key role in the lack of initial reaction by some of the inhabitants, which led to the human debacle witnessed by all. To this day, less than half the population has returned and the public services, public health, and educational systems have barely been re-established, thus threatening the long-term viability of the city. Solutions thus lie not only in rebuilding the levees but more importantly in rebuilding the social fabric and cultural heritage so badly battered by the storm. The approach selected by Tulane University in a project conceived and implemented in collaboration with UNESCO and the Stockholm Resilience Center aims at creating a democratic and informed public forum to foster the dialogue on recovery through research, public debate, grassroots exchange, and policy formulation concerning social, urban, and ecological resilience. The River Sphere, a riverside campus of Tulane University dedicated to researching and understanding the Mississippi and the other great rivers of the world, provides such a platform. There it is proposed that teams of scientists, engineers, educators, industrialists, and residents will convene and conduct research to increase understanding of coastal ecosystems and communities. (Meffert et al. 2004). 2) Improve equitable terms of access to resources. In Cape Town, South Africa, the Cape Flats Nature project implemented by the South Africa National Botanical Institute builds good practice in sustainable management of nature sites in the City’s Biodiversity Network. This is done in a people-centred way that develops local leadership for conservation action and benefits the surrounding communities, particularly townships
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where incomes are low and living conditions poor (Stanvliet et al. 2004). 3) Promote adaptive governance of urban landscapes at the relevant spatial and temporal scales by bringing all stakeholders together around a neutral space for learning and creation of public wealth. By applying the URBIS methodology, the public and private sectors will be able to share findings and make joint decisions about urban planning and development. Intercity agencies will be able to collaborate and contribute to an improved social, cultural, and ecological management platform. Furthermore, cities and urban regions around the world will be able to learn from each other and instigate better resilient design and planning for urban sustainability. There is hope that the ICLEI LAB and UNESCO URBIS initiatives will help to bridge science, planning, policy, and practice and reinvent a more holistic and symbiotic mode of urban development and resource use. This will not just require integration of
disciplines and sectors. The emerging paradigm should be built on the principles that saliency, legitimacy, and accountability are integral part of everything we do as public and private actors in the landscape. That applies to science, education, and governments, but also to those in the corporate sector that shape our cities through infrastructure and networks. In summary, in the urban landscape we propose to translate the general principles of the ecosystem approach and adaptive governance (Folke et al. 2005) into a set of methodologies, discourses, and planning tools ranging from global to local scales, recognizing that: (1) in an urbanizing planet cultural and biological diversity is key to resilience of social, economic, and ecological systems, (2) knowledge, either scientific or local, is key to management, (3) education is the main conduit for mainstreaming and empowering communities, and (4) adaptive management is not only a matter of building flexible institutions and governance systems at the relevant scale, it is also dependent on equity and particularly equitable access to land and resources.