Comparing approaches towards spontaneous vegetation in urban green structures

Abstract

Urbanization causes negative environmental effects and leads to pressure on the nature within and surrounding cities. Increasing the levels of wildness in urban areas is a form of nature-based solution that can improve the biodiversity and improve residents’ well-being.

This study aims to find green structure approaches towards urban spontaneous vegetation in today’s Berlin, Germany and Oslo, Norway. This is done through document analysis of the cities’ planning documents.

The overall aim for the Berlin documents can be summarized as a wish to expand nature and wilderness in urban development areas, conserve biodiversity and ensure green access and high-quality environment for the residents. The overall aim of the Oslo documents is to design the urban landscape with local and sustainable measures, make a safe and attractive parks and open spaces.

This study finds that Berlin has a general positivity towards foreign species and monitor invasive species, while Oslo is negative towards foreign species because of the threat they put on Oslo’s indigenous species. Berlin looks at all green structures as part of biodiversity, even spontaneous vegetation, while Oslo wants preserve biodiversity by designing urban green spaces.

The background history and available land may be a factor that decides the acceptance towards urban spontaneous vegetation. Both Oslo and Berlin have a high construction development pressure, while only Berlin has sufficient land available for construction. Small patches of vegetation have a higher amount of invasive or foreign species, and indigenous species has a higher risk at surviving in bigger patches.