Projects of the Urban Ecology Research Group
As part of climate adaptation strategies, many cities are developing master plans to cool urban heat islands. The research group Urban Ecology deals with spatial analyses, develops and optimizes measures and processes for effective cooling of urban spaces and buildings.
Contact: Stephan Brenneisen
Publications, student work and further information: Dachgrün im Stadtökosystem (PDF 1,4 MB), Bachelorarbeit Thierry Sebele (PDF 6,7 MB), Masterplan Klima Birsfelden (PDF 2,4 MB), Bachelorarbeit Seraphin Müller (PDF 11,7 MB)
The aim of the project "Citizens - Bees - Biodiversity Vorarlberg" is to valorize and thus further disseminate measures for flower-visiting insects Furthermore, the knowledge about green roofs, their effects and possibilities in the region of Lake Constance shall be strengthened. The potential of biodiversity and retention roofs has so far hardly been seen as a possible climate change adaptation measure or as a possibility for substitute habitats for insects and birds and thus also as a steppingstone for biotope connection in the settlement area.
Contact: Stephan Brenneisen
Since the greening of the roofs of the Seewasserwerk Moos in Wollishofen in 1918, a rich flora has developed and been preserved. The value of the green roofs was recognized and documented by Elias Landolt in 2001. 175 plant species, some of them rare and endangered, including 8 orchid species, were identified. Since 2015, the Urban Ecology Research Group has been accompanying the upcoming renovation work on the buildings, with the aim of securing the valuable green roofs beyond the construction phase.
Publications, student work and further information: Aktueller Zustand der Dachbegrünungen des Seewasserwerks Moos (PDF 3,2 MB), Projektdetails
Within the framework of the action plan for the implementation of the Swiss Biodiversity Strategy, scientific findings on the ecological compensation potential of green roofs measures are being developed for the BAFU. These serve to review and further develop existing instruments for the implementation and promotion of biodiversity in settlement areas.
Publications, student work and further information: Dachbegrünungen und Biodiversität im Siedlungsraum Zwischenbericht (PDF 1,6 MB), Heuschrecken auf Gründächern (PDF 2,4 MB), Bachelorarbeit Jonas Frei (PDF 7,6 MB)
The lapwing, a ground-nesting bird species threatened with extinction in Switzerland, breeds mainly in agricultural areas on fields. However, breeding attempts or broods on greened flat roofs also occur time and again. We investigate in almost traditional roof breeding areas in Emmen, Canton Lucerne and other locations under which conditions greened flat roofs do not become an ecological trap for lapwings, but allow successful breeding. Enhancement measures for the enrichment of the soil fauna are established and their effect is investigated.
Publications, student work and further information: Kiebitzbruten auf Flachdächern in Emmen (PDF 814,9 KB)
Direct revegetation methods (hay transfer) involve the transfer of seed from species-rich donor areas as a valid alternative to seed mixes to increase target area biodiversity or create ecological corridors. The most used methods for transferring and collecting valuable diaspora material are hay threshing (meadow threshing), hay brushing (brush out), hand-collected seed (hand collecting) and hay transfer. We apply several of these methods to green roofs and study vegetation development.
Contact: Stephan Brenneisen
The urban ecology research group supervises topic related student projects and collects long-term data on the distribution of fire salamander populations at various watercourses in the Wädenswil area. The aim of the data collection is to gain knowledge about the population structure of fire salamanders in the settlement area. Among other things, any exchange between spatially separated populations will be documented by means of photo-identification. The students are involved in the data collection and analysis in the context of semester- and bachelor theses.
The in large quantities occurring death of amphibians on roads near spawning grounds can be prevented to a large extent through evidence-based amphibian protection. During spring amphibian migrations, countless volunteers engage in amphibian conservation efforts to help amphibians to cross roads safely. To relieve volunteers, amphibian tunnels are built at particularly busy locations. The research group Urban Ecology accompanies projects on amphibian guidance systems and participates in success controls. For example, on behalf of the Swiss Federal Office for the Environment, it investigated how amphibian populations have developed ten years after the construction of guidance systems and ascertained how well a particular system is working.
Contact: Stephan Brenneisen
Publications, student work and further information: Gastbeitrag Inside - Funktionieren Amphibientunnel? (PDF 764,3 KB), Gastbeitrag Inside - Verkehrsregelung für Amphibien (PDF 1,1 MB), Evidence-Based Amphibian Conservation A Case Study on Toad Tunnels (PDF 1,1 MB), Semesterarbeit Svenja Hirt (PDF 6,2 MB), Semesterarbeit Andreas Seitz (PDF 20,3 MB), Semesterarbeit Eveline Häsli und Andreas Hofstetter (PDF 6,7 MB)
The Urban Ecology Research Group propagates native orchids generatively (from seed) with the aim of establishing them on natural sites, but mainly on natural green roofs (see Establishment of native orchids on extensive green roofs). Propagation takes place in vitro and is always as close to nature as possible. In addition to asymbiotic propagation on standard nutrient media, we focus on basic research in the field of symbiotic propagation. Possible symbiotic partners for orchids are isolated and the interaction of mycorrhizal fungi with different orchid species is investigated. In the process, fungal species that are unexplored and unknown to science keep coming to light.
Publications, student work and further information: Gastbeitrag im Pacific Horticulture Magazine - Orchid Resilience Green Roof Conservation in Switzerland (PDF 675,9 KB)
Field studies by the Urban Ecology Research Group have shown that green roofs are habitats for native orchids. In 2009, eleven orchid species were found to have spontaneously colonized green roofs throughout Switzerland. Orchids are considered to be weak in competition and react strongly to environmental influences such as nitrogen increase, soil compaction or intensive cultivation. Orchids can find a substitute habitat on near-natural designed and extensively maintained green roofs. Success parameters such as substrate type, substrate strength, water availability or maintenance were elicited and specifically applied to newly established green roofs. Since spontaneous establishment can take many years, initial planting with seedlings propagated in vitro (see In Vitro Propagation of Native Orchids) supports orchid establishment. If an orchid population can establish itself on a green roof, an increased ecological value can be determined due to the orchids and their accompanying plants. Orchids are not only seen on roofs as a seal of approval for species-rich and functioning habitats. Orchid meadows also provide an adequate habitat for many other floristic and faunistic groups and thus increase biodiversity in urban areas.
Publications, student work and further information: Gastbeitrag in Gallus-Stadt Orchideen auf den Dächern des Kantonsspitals (PDF 733,4 KB), Projektdetails
On the 1914-18 built and greened water treatment buildings of the Seewasserwerk Moos in Wollishofen a rich flora could develop and maintain itself. In the more than 100 years a species-rich "orchid meadow" with nine orchid species, some of which are rare and all of which are protected throughout Switzerland established. Since 2009, the orchid populations have been monitored by the Urban Ecology Research Group. In this process, all blooming orchids in the always same sub-areas are counted annually with a systematic sampling procedure. In order to estimate the populations of the whole roof area, the data are extrapolated. The long-term monitoring shows that the number of flowering individuals is subject to strong fluctuations. Of the most common orchid on the roofs, the green winged orchid (Anacamptis morio), an average of 15,104 individuals bloomed over the last ten years. The number of individuals recorded can be compared with the first vegetation survey carried out in 1999 by the geobotanist Elias Landolt. Based on the site preferences of the various orchid species and in combination with the indicator values of the 128 other vascular plant species that could be detected on the roofs in 2019 (see Floristic and vegetation ecology analyses of the green roofs of the Seewasserwerk Moos), a trend can be identified: "If we look at the "turnover" species, we see that especially species of wet habitats decreased, while those with medium and low moisture requirements increased." The reason for this is probably the increase in dry and sometimes very dry vegetation periods observed over the last two decades.
Publications, student work and further information: Vierteljahrsschrift NGZH - Ein Refugium für Orchideen (PDF 6,0 MB), Aktueller Zustand der Dachbegrünungen des Seewasserwerks Moos (PDF 3,2 MB)
As a result of intensive human use, light forests rich in structure and species were widespread in Switzerland until the 19th century. The habitat "light forest" is considered to be particularly diverse and offers ideal habitat conditions for many warmth- and light-loving plant and animal species. Successively, light forest sites have developed into dense and dark high forests, which are not only managed differently, but also no longer represent an ideal habitat for many light- and heat-loving species due to the heavy shading. Keeping open light forest sites is extremely time-consuming and cost-intensive, but in view of the threat of habitat loss, there is virtually no alternative.
The research group Urban Ecology is investigating in a field trial the influence of grazing of scrubby sites on the vegetation. Is it possible to restore or maintain the sparse condition of the area and can the orchids defined as target species benefit from the measures? An initial success control has shown that both mechanical management and grazing by goats have a positive effect on the vegetation.
Publications, student work and further information: Bachelorarbeit Selina Sigrist (PDF 6,0 MB)
Beetles are an important group of deadwood recyclers and decomposers, and their occurrence says a lot about the condition of individual trees to entire forest areas. The diversity of the beetles living in and on deadwood seems to be almost infinite. The urban ecology research group is involved in a variety of studies with different project partners. In various research projects these xylobiont beetles are collected, determined and used to assess the quality of the study site. Special mention should be made of the study in the Crap Ses pine forest, in which five first records for Switzerland were obtained.
Publications, student work and further information: Vielfalt der Totholzkäferfauna im Waldföhrenwald Crap Ses, Surses (Graubünden) (PDF 879,9 KB), «Primeval forest relict beetles» of Central Europe: a set of 168 umbrella species for the protection of primeval forest remnants (PDF 1,6 MB)
Switzerland has a special responsibility for the beetles of the alpine sites, especially the high mountain species, many of which are endemic or relict. They are the oldest species of the native beetle fauna. Their study can tell us a lot about the evolution and also the genesis of the landscape. The work of the Urban Ecology Research Group has already led to the description of several new species of the Alpine region, also for Switzerland.
Publications, student work and further information: Oreonebria (Marggia) bluemlisalpicola sp. nov., eine neue hochalpine Laufkäferart der nordwestlichen Schweizer Alpen (PDF 787,9 KB), Neubewertung von Nebria (Nebriola) heeri, Untersuchung über das Vorkommen des Schnellkäfers Berninelsonius hyperboreus (GYLL.) in Nidwalden (PDF 840,3 KB), Schlussbericht Projekt Reliktpopulationen von endemischen Prioritätsarten aus den Schweizer Nordalpen (PDF 1,4 MB)
Green roofs are important ecological compensation areas in urban areas. Depending on substrate thickness and composition, a different habitat is created and thus different beetle species settle. A wide range of more or less heat- and light- preferring species, reminiscent of those of dry and semi-dry grasslands, find a secondary habitat on green roofs. The Urban Ecology Research Group has been studying the occurrence of beetles on green roofs for over a decade. To date, around 54,355 beetle individuals have been counted and identified. Thus, 543 beetle species could be detected on green roofs.
Publications, student work and further information: A Global Comparison of Beetle Community Composition on Green Roofs and the Potential for Homogenization (PDF 861,2 KB), Carabiden communities on green roofs in Switzerland - synthesis and perspectives (PDF 2,0 MB)
In recent years, a conflict of goals has arisen in the use of building roofs. After the catastrophe of Fukushima and the subsequently elaborated energy strategy of the federal government 2050, roof areas are increasingly used for the installation of photovoltaic systems. In practice, unfortunately, such green roof areas often have to give way when solar energy use is subsequently installed on a roof.
We develop and investigate installation methods and technologies how the combined solution of green roofs and solar energy use works and represents a gain for the climate adaptation of cities through precipitation retention, biodiversity as well as energy production.
Publications, student work and further information: Vertikal aufgeständerte, bifaciale Solarmodule zur PV-Nutzung begrünter Dächer (PDF 5,3 MB), Semesterarbeit David Hauswirth (PDF 3,2 MB)
Eco-faunistic and vegetation assessment and optimisation of green roof areas
Within the framework of the action plan for the implementation of the Swiss Biodiversity Strategy, scientific principles and findings on the ecological compensation potential of greening buildings are to be developed. On this basis, existing instruments for the implementation and promotion of biodiversity in urban ...
Citizens, bees, biodiversity
Bürger - Bienen -Biodiversität Vorarlberg (BBB-V) is part of the Interreg project ABH83 Bürger - Bienen - Biodiversität with the project partners Bodenseestiftung (Leadpartner), BUND Naturschutz Ökostation Schwaben e.V. and Umwelt- und Klimaschutzabteilung im Amt der Vlbg Landesregierung. The project Bürger - Bienen ...
Biochar in greenroof substrates
Floristic and vegetation-ecological analyses of the green roofs of the lake water plant
The water supply system of the city of Zurich is planning major construction works at the Moos plant. The green roofs with nature conservation value (> 100 years old, with botanical values of cantonal importance (Landolt 2001)) are to be preserved wherever possible. The Urban Ecology Research Group has developed a ...
More than hay
The general aim of this and future projects is to consolidate the knowledge on the application of direct greening methods on green roofs namely to adapt typical ecological restoration procedures to urban ecological design and praxis. Specific aims of this project are: 1) to set up of a first inventory with the old, ...
orchid green roof Natur- und Tierpark Goldau
Analysis and Evaluation of the garden design of the housing development Glancenberg no.12 and 26-28 in Dietikon belonging to the housing association Eigengrund
The outdoor spaces of the housing estate Glanzenberg 12 and 26-28 were re-designed according to the outcomes of qualitative interviews with inhabitants and other stakeholders and taking aethetic, ecological and economic aspects into consideration. The goal was to enhance the possibilities for appropiation of the ...
Green roof concept urban development Zurich railway station