Ecosystem services and the contributions of nature in the city

 

By Joshua Aldridge and Sergio Andres Velez Triana

Ecosystems services have hit the spotlight since the early 2000s when they were first addressed academically. However, knowledge of them amongst the general public is still sparse, with some ecosystem services being acknowledged far more than others. This short blog post will briefly explain what ecosystem services are before discussing some of the lesser-known benefits of having nature in the city.

So what are ecosystem services? Simply speaking, they are the benefits that we derive from nature, both directly and indirectly. They can be split into four main categories. These are: supporting, regulating, provisioning and cultural. Supporting services are considered ecological functions, and therefore, they are processes that allow for regulating, provisioning, and cultural ecosystem services. The regulating ecosystem services (RES) protect the environment through climate regulation, erosion control, and pollination. Provisioning services refers to the benefits that we can directly receive from natural ecosystems and ecological processes, including food, biomass and medicines. Finally, we have cultural services which are more intangible and provide things such as recreation, psychological, and spiritual values, or cultural and social cohesion (CICES, 2023).

 

Figure 1. A visualisation of the ecosystem service categories (Earthwise Aware, 2021).

Often, nature, be it in urban or rural areas is viewed from a regulating ecosystem services perspective. That is to say that when we think of the benefits of trees and green areas, we first consider them as the providers of oxygen and clean air. Whilst oxygen is of course vital for humans, these types of services cover a small extent of the total ecosystem services that nature offers to us as humans.

One interesting outcome of having urban green in the city was acknowledged by Roger Ulrich in a study completed in 1984. Hospitals are a sterile environment, often devoid of colour. Those that have had a prolonged stay in a hospital will recall the white walls, grey floors and bleak view out the window of their ward. One might consider that a more colourful and vibrant environment would bring to the fore more positive emotions and perhaps elicit a better response in health. This is exactly what Ulrich found. Simply by having nature of some form visible from a patient’s hospital room, their speed of recovery was increased (Ulrich, 1984). This an example of a cultural ecosystem service, where nature improves someone’s physical or mental health. It is precisely this type of ecosystem service that is so difficult to measure because everyone is affected differently by nature.

These psychological benefits of green spaces extend beyond the hospital ward. Mental well-being has been noted to improve simply by owning indoor house plants, whilst the act of gardening or walking through parks has been shown to reduce symptoms of depression in adults. Beyond this, actively accessing green spaces can have the indirect benefit of increasing social interactions (Tran, Sabol, & Mote, 2022).

Trees and other vegetation can also reduce the temperature of the city, combatting the urban heat island effect. This is a phenomenon that occurs in urban areas where heat is trapped by buildings, roads and pavements before being slowly emitted, resulting in increased temperatures compared to surrounding rural areas. Trees combat this effect as they provide shade and block sunlight from reaching paved surfaces.

Another, lesser known benefit of having nature in the city is the potential of preserving and promoting traditional cultural heritage. Green areas in cities may offer the perfect space for diverse traditional practices in which social cohesion among different people is strengthened. Among these practices, we can highlight urban agriculture, which can be considered as the recreation of the rurality in the cities. Through urban agriculture not only the rural traditional knowledge can be transferred to people that live in cities, but at the same time, can help to preserve the cultural heritage of people that have moved from rural contexts.

 

Figure 2. Urban agriculture processes in Bogota, Colombia. Map based on data layers obtained from the Botanical Garden of Bogota.

In Bogotá, Colombia, for example, urban agriculture is mainly led by women peasant farmers that have moved to the city in recent years. These women have important traditional ecological knowledge (TEK) that can be preserved through the implementation of green areas that incentivize the implementation of urban agriculture (Colibris, 2019). Moreover, social cohesion in cities can significantly increase through the collective scenarios that green areas and urban agriculture offer. Ultimately, traditional ecological knowledge and ecosystem services support each other in a mutual relationship, since TEK also help to preserve certain plant species, many of them medicinal.

 

Figure 3. Photographs of an urban agriculture process in Bogota, Colombia (Colibris, 2019).

It must also be noted, as we are discussing ecosystem services, that ecosystem disservices exist. Though we will not delve into these in any detail, these are ecological processes that can generate nuisances and have indirect or direct impacts on people. Some of the different impacts that can be detailed are pests, animal attacks, allergies, and natural hazards (Von Dohren & Haase, 2015). There has been a significant increase in academic production regarding this topic as can be seen in the next figure.

 

Figure 4. Number of papers addressing ecosystem disservices (Von Dohren & Hasse, 2015).

Finally, much of the research completed on the benefits of urban green has focussed on cities located in the ‘western’ world, with white participants seriously overrepresented (Gallegos-Riofrio, et al., 2022).

Conclusion

It is clear that nature both within and outside of urban areas has a range of benefits, with many of these unknown to, or rarely acknowledged by the general public. We hope that this blog has been informative in explaining the basics of ecosystem services as well as highlighting the disservices and bias within current academic research. This was only a brief overview of some of the ecosystem services that we can identify in cities. We must note that all the benefits derived from ecosystems depend not only on ecological processes but are at the same time dependent on how people interact with them and use those benefits.

 

 

References

 

CICES. (2023). Towards a common classification of ecosystem services. European Environment Agency. .

Colibris, 3. (2019). De ladrillera a huerta urbana en Bogotá. [Fotoreportaje]. Retrieved from 3 Colibris: https://3colibris.com/2019/09/22/de-ladrillera-a-huerta-urbana-en-bogota-fotoreportaje/comment-page-1/.

Earthwise Aware. (2021). What are Ecosystem Services. Retrieved from Earthwise Aware: https://www.earthwiseaware.org/what-are-ecosystem-services/

Gallegos-Riofrio, C. A., Arab, H., Carrasco-Torrontegui, A., & Gould, R. (2022). Chronic deficiency of diversity and pluralism in research on nature's mental health effects: A planetary health problem. Current Research in Environmental Sustainability, 1-11.

Tran, I., Sabol, O., & Mote, J. (2022). The Relationship Between Greenspace Exposure and Psychopathology Symptoms: A Systematic Review. Biological Psychiatry Global Open Science, 206-222.

Ulrich, R. (1984). View Through a Window May Influence Recovery from Surgery. Science, 420-421.

Von Dohren, P., & Haase, D. (2015). Ecosystem disservices research: A review of the state of the art with a focus on cities. Ecological Indicators, 490-497.