7 research outputs found
Report from the Master summer school “Biodiversity Monitoring”, Preda, Parc Ela, Switzerland, 10–20 August 2020
No full textScale-dependent patterns and drivers of vascular plant, bryophyte and lichen diversity in dry grasslands of the Swiss inneralpine valleys
No full textThe inner-alpine dry valleys of the Swiss Alps are characterized by subcontinental climate, leading to many peculiarities in dry grassland species composition. Despite their well-known uniqueness, comprehensive studies on biodiversity patterns of the dry grasslands in these valleys were still missing. To close this gap, we sampled 161 10-m2 vegetation plots in the Rhône, Rhine and Inn valleys, recording vascular plants, terricolous bryophyte and lichen species, as well as environmental data. Additionally, we tested the scale-dependence of environmental drivers using 34 nested-plot series with seven grain sizes (0.0001–100 m2). We analysed the effects of environmental drivers related to productivity/stress, disturbance and within-plot heterogeneity on species richness. Mean species richness ranged from 2.3 species in 0.0001 m2 to 58.8 species in 100 m2. For all taxa combined, the most relevant drivers at the grain size of 10 m2 were southing (negative), litter (negative), mean annual precipitation (unimodal), gravel cover (negative), inclination (unimodal) and mean annual precipitation (unimodal). For vascular plants the pattern was similar, while bryophyte and lichen richness differed by the opposite relationship to mean annual precipitation as well as negative influences of mean herb layer height, grazing and mowing. The explained variance of the multiple regression model increased with grain size, with very low values for the smallest two grain sizes. While southing and litter had high importance for the fiver larger grain sizes, pH and gravel cover were particularly important at the intermediate grain sizes, and inclination and mean annual precipitation for the two largest grain sizes. The findings emphasize the importance of taxonomic group and grain size for patterns and drivers of species richness in vegetation, consistent with ecological theory. Differences in the diversity–environment relationships among the three taxonomic groups can partly be explained by asymmetric competition that leads to low bryophyte and lichen diversity where vascular plants do well and vice versa. The relatively low alpha diversity of vascular plants in dry grasslands in Swiss inner-alpine valleys compared to similar communities in other parts of the Palaearctic remains puzzling, especially because Swiss stands are often large and well-preserved
IUNR Campus-Tag der Biodiversität : erste "Volkszählung der Biodiversität" auf dem Campus Grüental der ZHAW Wädenswil
No full textJagen, fangen, pflücken, bestimmen, auflisten – das war die Devise am IUNR Campus-Tag Biodiversität, der am 6. Juni 2019 erstmals stattfand. Und zwar alles, was auf dem Gelände des Campus Grüental der ZHAW in Wädenswil an Pflanzen und Tieren an diesem Tag zu finden war. Die rund 80 Teilnehmenden, je zur Hälfte UI-Studierende und IUNR-Mitarbeitende, hatten die Qual der Wahl zwischen 11 verschiedenen Artengruppen, bei denen sie mitmachen konnten
Two international postdocs at the IUNR : interview with Iwona Dembicz and Jinghui Zhang
No full textPhD students and Postdocs are generally rather rare at the IUNR compared to full universities where these two groups account for a big fraction of the staff. In the academic year 2019/20 two Postdocs have joined the Vegetation Ecology Research Group, Dr. Iwona Dembicz from Poland for 9 ½ months and Dr. Jinghui Zhang from China for a whole year. We have interviewed them to shed a light on why they specifically selected the IUNR for their research stay and how they experienced the institute, the region and Switzerland in general
Determination of habitat requirements of the glacial relict Nuphar pumila as basis for successful (re-)introductions
No full textNuphar pumila is a glacial relict, which is nowadays rare throughout Europe and red-listed in most European regions. In Switzerland only three autochthonous populations and one population of the hybrid with N. lutea (N. ×spenneriana) have survived to date, one of them in the canton of Zurich. To protect this species regionally, the canton of Zurich has commissioned the ex situ propagation of speci-mens, which then had been introduced to 37 water bodies in protected areas, including one known former site. Since only about 10% of these introductions had been successful, there was a wish to identify causes of this lack of success. To this end, we compared the vegetation and physical-chemical parameters of the four natural sites in Switzerland with the successful and unsuccessful introduction sites. Additionally, for a subset of sites, we assessed diatom genus composition as a proxy of water quality. Moreover, we derived vegetation plots of N. pumila and N. lutea from across Europe from the European Vegetation Archive (EVA) to compare their site conditions, using mean ecological indicator values and bioclimatic variables of the localities. We found that inside Switzerland the main differences were between the natural sites and all introduction sites, while successful and unsuccessful introduction sites hardly differed in the determined parameters. Natural sites had cooler water with lower magnesi-um content, and according to mean ecological indicator values, also lower nutrient status. The diatom data, though limited in amount, point into the same direction. The EVA data demonstrate that stands of N. pumila are mainly more oligotrophic, but also cooler and more acidic than those of N. lutea. We could not find any factor that explains the success vs. lack of success of plantations of N. pumila in multiple sites in the canton of Zurich, but our results rather indicate that due to the relatively warm climate, the high atmogenic nitrogen input and the predominantly base-rich bedrock, the sites in the canton are generally not particularly well suited for N. pumila. We consider it therefore more promising to protect and possibly (re-)introduce N. pumila in other cantons with higher elevation, base-poor bedrock and lower atmogenic nitrogen input
Dry grasslands of the central valleys of the Alps from a European perspective : the example of Ausserberg (Valais, Switzerland)
No full textThe upper Rhone valley in the Swiss canton of Valais is one of the driest and most continental of the inner-alpine valleys and harbours a rich xerothermic flora. We studied syntaxonomy and ecology of dry grasslands and their species richness patterns. In 2018 we recorded 28 vegetation plots (10 m²) and three nested-plot series of 0.0001 to 100 m² on the south-facing slopes above the village of Ausserberg. Mean richness of all species ranged from 1.7 on 1 cm² to 47.3 on 100 m², with little contribution of bryophytes and lichens. The species-area relationship for total richness closely followed a power function. Modified TWINSPAN yielded a three-cluster solution, which could easily be matched with three orders of the class Festuco- Brometea: Stipo pulcherrimae-Festucetalia pallentis (xeric, rocky), Festucetalia valesiacae (xeric, non-rocky) and Brachypodietalia pinnati (meso-xeric). The subdivision of the xeric types into two orders is new for Swiss dry grasslands, where these types up to now had been joined in a single alliance Stipo-Poion within the Festucetalia valesiacae
On the trails of Josias Braun-Blanquet II : first results from the 12th EDGG Field Workshop studying the dry grasslands of the inneralpine dry valleys of Switzerland
No full textThe 12th EDGG Field Workshop took place from 11 to 19 May 2019, organised by the Vegetation Ecology Group of the Institute of Natural Resource Sciences (IUNR) of the Zurich University of Applied Sciences (ZHAW). Like in the 11th Field Workshop in Austria, the main target was the "Inneralpine Trockenvegetation" (Festuco-Brometea and Sedo-Scleranthetea), which was first extensively sampled by Josias Braun-Blanquet and collaborators during the 1950s. We visited the Rhône valley in the cantons of Vaud and Valais, one of the most ex-treme xerothermic islands of the Alps and the Rhine and Inn valleys in the canton of Grison. In total, 30 nested-plot series (EDGG biodi-versity plots) of 0.0001 to 100 m² and 82 plots of 10 m² were sampled in meso-xeric, xeric and rocky grasslands of 25 different sites, rang-ing from 500 to 1,656 m a.s.l., under different topographic, bedrock and landuse conditions. All vascular plants, bryophytes and lichens were recorded in each plot, along with their cover values. We found on average 28.9 vascular plants on 10 m²; which was the lowest mean species richness of any previous EDGG Field Workshop. These values are comparable to the average species richness values of dry grasslands of the Aosta valley in Italy. The data sampled will be used to understand the biodiversity patterns regionally and in the Palae-arctic context as well as to place the Swiss dry grasslands in the modern European syntaxonomic system
