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Land abandonment and intensification of management have been suggested as major drivers of biodiversity change in subalpine and alpine grasslands, but the relative importance of these concomitant trends has not been extensively studied. Here, we use plant indicator values to infer patterns of change in the management intensity of summer pastures. Occurrence data of vascular plants from 192 plots surveyed in the Swiss Biodiversity Monitoring BDM programme were used to analyse changes in five species-based indicator values that express the management intensity of sites. Each plot was surveyed twice between 2002 and 2011 with a time span of 5 years between surveys. We looked for an overall trend in management intensity and examined whether a supposed change of management intensity depends on site conditions. In addition, we tested whether a change in indicator values for management intensity accompanies a change in species richness. Over the whole study area, there was no overall change in mean indicator values. However, we found weak but significant relations between changes in mean indicator values and accessibility of the sites. According to plant indicator values, intensification of management takes place at well-accessible and lower-elevation sites, whereas remote sites and sites at higher elevation tend to show a decrease in management intensity. Sites where indicators suggested intensified management showed a decrease of both total species richness and richness of target species relevant for conservation. On the other hand, a supposed decrease in land-use intensity led to an increase in species richness within the surveyed time period. This study confirms that moderate management intensity of summer pastures will best maintain the plant diversity of alpine summer pastures. Because the surveyed plots stem from a rigorously standardized regular-grid sampling, we attribute high reliability and generality to our findings.

Strebel, N., & Bühler, C. (2015). Recent shifts in plant species suggest opposing land-use changes in alpine pastures. Alpine Botany, 125(1), 1–9. https://doi.org/10.1007/s00035-015-0145-3

Genetische Vielfalt als eine der drei Ebenen der biologischen Vielfalt wurde bisher bei der Überwachung der Biodiversität kaum beachtet. Dank sinkender Kosten für genetische Analysen ist die Durchführung eines Monitorings der genetischen Vielfalt natürlicher Populationen erschwinglich geworden. Am Beispiel des Schachbrettfalters wird aufgezeigt, wie die Probenahmen im Feld organisiert werden und welche Erkenntnisse eine gängige genetische Methode erbringen können.

Schmid, M., Birrer, S., Bolliger, S., Csencsics, D., & Gugerli, F. (2015). Monitoring genetischer Vielfalt: Fallbeispiel Schachbrettfalter. N&L Inside 19-24.

Estimating effects of nitrogen (N) deposition is essential for understanding human impacts on biodiversity. However, studies relating atmospheric N deposition to plant diversity are usually restricted to small plots of high conservation value. Here, we used data on 381 randomly selected 1 km² plots covering most habitat types of Central Europe and an elevational range of 2900 m. We found that high atmospheric N deposition was associated with low values of six measures of plant diversity. The weakest negative relation to N deposition was found in the traditionally measured total species richness. The strongest relation to N deposition was in phylogenetic diversity, with an estimated loss of 19% due to atmospheric N deposition as compared with a homogeneously distributed historic N deposition without human influence, or of 11% as compared with a spatially varying N deposition for the year 1880, during industrialization in Europe. Because phylogenetic plant diversity is often related to ecosystem functioning, we suggest that atmospheric N deposition threatens functioning of ecosystems at the landscape scale.

Roth, T., Kohli, L., Rihm, B., Amrhein, V., & Achermann, B. (2015). Nitrogen deposition and multi-dimensional plant diversity at the landscape scale. Royal Society Open Science, 2(4), 150017. https://doi.org/10.1098/rsos.150017

The growing awareness of biodiversity by forest managers has fueled the demand for information on abiotic and biotic factors that determine spatial biodiversity patterns. Detailed and area-wide environmental data on potential predictors and site-specific habitat characteristics, however, are usually not available across large spatial extents. Recent developments in environmental data acquisition such as the advent of Light Detection And Ranging (LiDAR) remote sensing provide opportunities to characterize site-specific habitat conditions at a high level of detail and across large areas. Here, we used a dataset of regularly distributed local-scale records of vascular plant, bryophyte and snail (Gastropoda) species to model richness patterns in forests across an environmentally heterogeneous region in Central Europe (Switzerland). We spatially predicted species richness based on a set of area-wide environmental factors representing climate, topography, soil pH and remotely sensed vegetation structure. Additionally, we investigated the relationship between species richness and field measures of forest stand structure and composition obtained from National Forest Inventory (NFI) data to identify potential target variables for habitat management. The predictions for species richness were most accurate for snails, followed by bryophyte and vascular plants, with R² values ranging from 0.37 to 0.07. Besides climate, site-specific factors such as soil pH, indices of topographic position and wetness as well as canopy structure were important for predicting species richness of all three target groups. Several NFI variables were identified as potential target variables for managing snail species richness. Stands with tree species from the genera Fraxinus, Tilia, Ulmus and Acer, for example, showed a positive relationship with snail species richness, as did an increasing overstory cover or higher volumes of deadwood. However, only weak relationships were found between NFI variables and species richness of vascular plants, and none for bryophytes. Our findings support the assumption that besides climate, site-specific habitat factors are important determinants of spatial variation of species richness at the local scale. The strength and direction of the determinants vary with taxa, thus indicating a functional relationship between site conditions and the respective species community.

Zellweger, F., Braunisch, V., Morsdorf, F., Baltensweiler, A., Abegg, M., Roth, T., Bugmann, H., & Bollmann, K. (2015). Disentangling the effects of climate, topography, soil and vegetation on stand-scale species richness in temperate forests. Forest Ecology and Management, 349, 36–44. https://doi.org/10.1016/j.foreco.2015.04.008