Ground beetle (Coleoptera: Carabidae) communities on green roofs in Switzerland: synthesis and perspectives

Abstract

Green roofs have recently gained recognition for their potential contribution to urban ecosystems by providing, among other services, habitat for plants and animals, and stepping stones for mobile organisms, thereby enhancing permeability among habitat patches across densely built cities. In Switzerland, investigations over the past 20 years on more than one hundred distinct green roofs across six cities have provided an unprecedented dataset on ground beetles, albeit with information that is scattered across unpublished reports and local databases. We present here for the first time a synthesis of the state of knowledge of ground beetle communities from green roofs in Switzerland. We describe 91 ground beetles species (19,428 individuals) and highlight patterns of species occurrence and composition across green roofs and cities. Most of the roofs host ground beetle communities dominated by five common mobile species with quite diversified ecological requirements. In addition, we observed nine species (10% of all species collected) that are conservation concerns in Switzerland and Central Europe as well as numerous stenotopic species (from grasslands and pioneer vegetation). This indicates that, besides sustaining local populations of common species, green roofs can also offer suitable ecological conditions of high conservation interest. We suggest both improving the design of green roofs (composition and configuration of vegetation, as well as soil depth and substrate composition) to increase their ecological value for species with the most different ecological needs, and to integrate green roofs into urban planning to make them more efficient as biodiversity supports.Keywords Biodiversity . Urban ecology . Urban green . Vertical green . Endangered species . Carabid beetles . Green infrastructures . Red list species * Gaël Pétremand

Land snail dispersal, abundance and diversity on green roofs

“…As has been found with several other invertebrate taxa [2,27,32], the species inhabiting green roofs tend to be widespread, generalist and disturbance-adapted species. The same studies also show that just a few species tend to dominate in terms of total abundance and being the most widespread among green roof habitats.…”

“…On the other hand, our findings are similar for non-flying taxa. A review of 102 green roofs in Switzerland found just 91 ground beetle species [32].…”

Green Roofs and Green Walls for Biodiversity Conservation: A Contribution to Urban Connectivity?

“…Studies have also confirmed the presence of arthropods, such as beetles, spiders, true bugs, hymenopterans (ants, bees, wasps), flies [50][51][52], springtails (up to 44 species) [53,54], and mites [55], in addition to fungi [54,55] and bacteria [56]. A recent review conducted in six Swiss cities over the past 20 years showed that 91 out of the 532 species (17%) known in Switzerland are represented on green roofs [57]. Roofs are also habitat for vertebrates.…”

“…With moisture being the limiting factor controlling plant growth, plants and fauna are mainly heliotropic, thermophilic, xerophilic or mesophilic, acidophilic and oligotrophic, and originate from grasslands and pioneer habitats, showing a wide variety of functional traits for pollination, dispersal, and reproduction [49,50,54,57]. …”

The Effect of Landscape on the Diversity in Urban Green Areas

“…According to Tóthmérész et al [38], 50 species were found in forests nearby the city of Sfantu Gheorghe along rural-urban gradient (Romania). Over the past 20 years in six Swiss cities the 91 ground beetles species were recorded on green roofs [39]. In three woodlands in the City of Debrecen (Hungary) 50 species of carabid beetles were registered [40].…”