Brownfields have a long history of neglect – it is after all abandonment that led them to the state they are in now. Characterised as areas where industrial activity has ceased1, brownfield sites have recently stirred a fair bit of controversy in the UK.
Their future is one of the current hot topics in both conservation and urban planning. There is ongoing debate about the proposed redevelopment of brownfield sites into housing. The arguments of conservationists highlight the importance of brownfield sites for biodiversity in an urban setting2. Further insight on the issue was presented by Cameron Campbell at our Conservation Science conference.
When urban sites are abandoned with no further human interference, what was once an ‘ecological desert’ gradually starts to accumulate biodiversity.
Brownfields are often degraded and their soils could have increased toxicity levels. Species which can tolerate this disturbance establish first. These are usually grasses, which then act as facilitators for other plant species. The increased plant abundance attracts invertebrates and birds3.
Urban settlements tend to decrease connectivity between natural habitats. Brownfields have the potential to act as important stepping stones or corridors) that facilitate animal movement. Furthermore, although they are far from pristine, in an increasingly industrially dominated landscape, they may very well be the best we have left. For many species of plants, invertebrates, small mammals and birds, brownfields represent refugia where they can find shelter and food2. Losing these sites will endanger the persistence of urban populations and might lead to the local extinction of species.
On the other hand, people need a place to live and redeveloping brownfield sites as opposed to clearing intact habitat seems like the smaller of two evils. Cameron admitted to the challenge urban planning poses and spoke of the importance of compromise: “Development projects should be concentrated on sites of lesser value for biodiversity. Furthermore, wherever houses are built, green spaces and gardens should be provisioned.”
Brownfield sites do in fact offer a unique opportunity. We have established that they can support high biodiversity, so we can include this knowledge in city planning and design not just houses, but a sustainable community. Ensuring that there are patches of land where plant colonisation can take place, maintaining wildlife meadows as well as fruit and vegetable allotments can all be beneficial for biodiversity4. People living in such places will be in closer contact with nature, which can help increase environmental awareness5. With all the education and conservation possibilities in mind, a brownfield site no longer seems like an unlikely place for a green attitude to sprout.
And indeed it has! Prompted by Cameron’s presentation, I went home wondering if there are any ongoing projects near Edinburgh and was happy to read about a successful initiative by the Edinburgh and Lothians Green Space Trust. A two-acre derelict site in Leith has been transformed into a green space with trees, meadows and paths for the local residents. My mind immediately burst with questions – were those trees native to the UK, what will happen to the site once funding is gone? While not ideal, projects like this are a step forward towards the successful cohabitation of people and urban wildlife. Now it is up to proactive individuals like you, me and Cameron to ask questions, seek solutions and offer support.
By Gergana Daskalova
1Alker, S., Joy, V., Roberts, P., and Smith, N. (2000). The Definition of Brownfield. Journal of Environmental Planning and Management 43: 49-69. (http://www.tandfonline.com/doi/abs/10.1080/09640560010766#.Vj5eoit0kg4)
2Angold, P.G., Sadler, J.P., Hill, M.O., Pullin, A., Rushton, S., Austin, K., Small, E., Wood, B., Wadsworth, R., Sanderson, R., and Thompson, K. (2006). Biodiversity in urban habitat patches. Science of the Total Environment 360: 196-204. (http://www.sciencedirect.com/science/article/pii/S0048969705005772)
3Small, E.C., Sadler, J.P., Telfer, M.G. (2003). Carabid beetle assemblages on urban derelict sites in Birmingham, UK. Journal of Insect Conservation 6: 233-246 (http://link.springer.com/article/10.1023/A:1024491111572)
4Goddard, M.A., Dougill, A.J., and Benton, T.G. (2009). Scaling up from gardens: biodiversity conservation in urban environments. Trends in Ecology & Evolution 25: 90-98. (http://www.sciencedirect.com/science/article/pii/S0169534709002468)
5Lindemann-Matthies, P. (2005). ‘Loveable’ mammals and ‘lifeless’ plants: how children’s interest in common local organisms can be enhanced through observation of nature. International Journal of Science Education 27: 655-677. (http://www.tandfonline.com/doi/abs/10.1080/09500690500038116#.Vj5fLCt0kg4)