Framework for urban ecosystem services

As cities expand their boundaries in response to growing populations, trade-offs in land use are inevitable. Very often, forests (natural capital) may need to be cleared to create land for housing and industries (built capital) with the aim of creating wealth for its citizens.

How should cities manage such trade-offs, with the knowledge that the reduction of forested land can alter a city’s hydrology and climate, leading to adverse consequences such as flash floods and the urban heat island effect?

Researchers from the Natural Capital Singapore and Ecosystem Services in Urban Landscape teams have developed a framework that represents a city’s dependence upon both natural and human-derived capital. This framework could guide the production of urban ecosystem services to meet societal goals, such as creating liveable and sustainable societies.

Concepts and frameworks are important in shaping the types of questions that scientists ask. In this context, definition of terms are equally important in scientific investigation—from problem statements to interpretations.

Urban ecosystem service (UES) is becoming an influential concept to guide the planning, design, and management of urban landscapes towards urban sustainability, and is increasing used in research, policy documents and by the media. However, its use is hindered by definitional ambiguity.

UES potentially produce benefits for humans. The implication is that human demand and use of UES eventually dictates societal decision-making via policies, professional practices and societal norms. These in turn, influence the use of natural and human-derived capital to generate UES through a feedback loop.

In the paper external page A conceptual framework to untangle the concept of urban ecosystem services published in Landscape and Urban Planning, researchers at the Natural Capital Singapore project clarified the relationships between different interpretations. This not only promotes consistent use, but importantly, explore how a broader interpretation of UES might advance its applications in areas that have been neglected.

Within the urban ecosystem, human well-being is dependent on a wide range of services; some of these are provided mainly by natural and semi-natural ecosystems, such as recreation in green open spaces and fresh food from urban aquaculture, while others, such as housing, transport, health, education and telecommunication, are created by humans. In the proposed framework, all these services can be defined as “services of urban eco-systems.

The authors, therefore, defined UES as “aspects of ecosystems that are generated from natural capital in combination with human-derived capital, and that contribute, directly or indirectly, to human well-being in urban areas”, which adequately captures both interpretations of UES.

In this definition, they use “ecosystem” rather than “urban ecosystem” to reflect the cross-scale dependence on movement of natural capital, and aspects of human-derived capital to meet human needs in urban areas.

This framework, along with the definition, grounded on the view of cities as urban ecosystems, more recently characterised as a socio-ecological-technological system, may also be valuable in clarifying the relationships between UES and related concepts.