Mapping an ecological network of green habitat patches and their role in maintaining urban biodiversity in and around Debrecen city (Eastern Hungary)

Abstract

Urbanisation is a leading process on the Globe causing a massive loss of natural habitats. In parallel variety of habitats were created in urban environments, which may also support species diversity. Our aim was to identify urban green areas and their connections with the Regional Ecological Network surrounding the city of Debrecen (East-Hungary), and to explore the biodiversity potential of the network of these parks. We found that whilst industrial areas, airport and mixed land covered a relatively large area, parks and other functional green spaces had a relatively small extent. However the green space system of the city is well connected to the Regional Ecological Network. We also surveyed the functional and potential green spaces in the city and in the studied patches of the Regional Ecological Network in and around the city. We found that 65% of the functional green spaces are potentially connected thus there is a possibility for species typical to semi-natural open habitats to disperse between the green spaces of the city. Based on the survey of the spontaneous flora and planted ornamentals we found that the ratio of native species was high in the studied urban parks. We found that native species were the most typical (>50%) in the spontaneous flora of the studied urban parks, although the ratio of archaeophytes and neophytes were also high. Among ornamental plants, both the proportion of native species and neophytes were considerable in each park, and the proportion of archaeophytes was low. Our results suggest that the studied urban habitats have some biodiversity conservation potential; they mostly harbour species which can cope with the local environmental conditions of the city parks, such as increased temperature, drought and nutrient enrichment.