Transitioning Towards Urban Resilience and Sustainability (TURAS) aims to enable European cities and their rural interfaces to build vitally-needed resilience in the face of significant sustainability challenges through Knowledge Transfer Partnerships. The increasing proportion of people living in urban areas has led to a range of environmental issues and sustainability challenges. In order to ensure that urban living is sustainable and that cities have the resilience to cope with environmental change these challenges must be met.
Restoration and re-creation of green infrastructure in urban areas is a potential solution to many of these challenges and in high density urban areas with little usable space at ground level, roof level green infrastructure has perhaps the greatest potential to contribute to re-greening urban areas. Given the increasing recognition that the natural environment can provide goods and services of benefit to humans and the planet (‘ecosystem services’), and that these services can provide resilience for urban areas, the European Commission is now advocating well-planned green infrastructure that provides opportunities to protect and enhance biodiversity.
In order to maximise biodiversity, and the associated ecosystem services, in urban areas it is necessary to incorporate local and regional environmental context into the design of urban green infrastructure. Unfortunately, the majority of green roof installations in London, across Europe and beyond are ‘off-the-shelf’ industry standard systems predominantly designed for aesthetics and stormwater attenuation and an assumption is made that by installing something green a range of additional ecosystem services will be restored. The resulting lack of plant diversity and habitat structure means that these green roof systems offer restricted biodiversity and associated ecosystem service benefits and mean that opportunities are missed for supporting urban biodiversity and building the associated resilience that biodiversity can provide. In order to ensure that further opportunities are not missed, it is necessary to take a local view of key ecosystems and habitats and incorporate these into green roof design using biomimicry.
A report just launched on the TURAS website comprises a key milestone from the TURAS research programme in relation to green roof design. This report details the findings from a Knowledge Transfer Partnership (KTP) established in Barking Riverside (London, UK) between Barking Riverside Ltd, the London Borough of Barking and Dagenham, Livingroofs.org, the University of East London and the Institute for Sustainability to establish whether there is an ecosystem service ‘cost’ associated with shifting away from industrial standard green roofs designed primarily as Sustainable Urban Drainage System (SuDs) components towards more biodiverse systems designed based on regional habitat characteristics. An investigation was carried out using trial green roof test systems to compare the effect on performance in terms of a number of ecosystem services of moving away from an industrial standard sedum system to a more biodiverse green roof system comprising wildflowers typical of the Barking Riverside area and of value to regional biodiversity of national conservation importance.
Of the ecosystem service performances monitored, summarised results of water attenuation, thermal and biodiversity performance are included in the report. Rather than demonstrating an ecosystem service cost associated with moving away from industrial standard systems, the biodiverse green roof systems performed as well as or superior to the equivalent sedum systems for water attenuation and thermal insulation and far out-performed the sedum systems in terms of supporting a diverse flora.
Results from the investigation are being fed into the design of green roofs throughout the Barking Riverside development and fed into the London Borough of Barking and Dagenham planning process. It is hoped that the results from this KTP will act as a blue print for use throughout the TURAS partnership and beyond to inspire further projects investigating the potential for the use of biomimicry of regional habitat of conservation value in the design of green roofs to maximise urban biodiversity.
For more information on the Knowledge Transfer Partnership, green roof experiment and results see the full report available on the TURAS website:
Connop, S., Nash, C., Gedge, D. Kadas, G, Owczarek, K and Newport, D.. 2013. TURAS Green Roof Design Guidelines: Maximising ecosystem service provision through regional design for biodiversity. London: University of East London.