Planning green infrastructure using habitat modelling : a case study of the common toad in Lomma Municipality

Abstract: For an ecosystem to be able to continue to provide important services to society, it must be able to adapt to change. As part of an ecosystem, the ability of a species to migrate in the landscape is vital for the adaption to change. A green infrastructure allows the movement of species in a landscape fragmented by human influenced land use. The importance of a green infrastructure is twofold in a changing climate. An increased frequency of extreme weather events will create changes in food availability, competition and the physical components of an ecosystem. A green infrastructure also provides services which are important for society’s adaption to climate change such as water retention and shade. This thesis looks at the composition of green infrastructure in Lomma municipality and the opportunities it provides for the common toad (Bufo bufo) to be able to migrate in the landscape. A habitat model was created for the common toad which was used to evaluate Lomma municipality’s plan for extending existing green infrastructure. Lomma is located in a low lying landscape on the Öresund coast. In a changing climate the risk for flooding in Lomma is predicted to increase. Flooding was used as an example of a disturbance on the municipality’s green infrastructure and the common toad’s habitat with the aim of facilitating planning of green infrastructure in the future. The result of the evaluation of Lomma municipality’s green infrastructure was that, in general, the common toad’s habitat followed the infrastructure. A number of locations in the landscape that lacked connectivity had been identified for new green corridors. The common toad is not representative of all species and so there were migration paths that did not conform to the green infrastructure plan. Using flooding as a disturbance resulted in a reduction in the toad’s habitat area and also caused a break in migration connectivity in the landscape.