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Amphipods are key organisms in many freshwater systems and contribute substantially to the diversity and functioning of macroinvertebrate communities. Furthermore, they are commonly used as bioindicators and for ecotoxicological tests. For many areas, however, diversity and distribution of amphipods is inadequately known, which limits their use in ecological and ecotoxicological studies and handicaps conservation initiatives. We studied the diversity and distribution of amphipods in Switzerland (Central Europe), covering four major drainage basins, an altitudinal gradient of >2,500 m, and various habitats (rivers, streams, lakes and groundwater). We provide the first provisional checklist and detailed information on the distribution and diversity of all amphipod species from Switzerland. In total, we found 29 amphipod species. This includes 16 native and 13 non-native species, one of the latter (Orchestia cavimana) reported here for the first time for Switzerland. The diversity is compared to neighboring countries. We specifically discuss species of the genus Niphargus, which are often receiving less attention. We also found evidence of an even higher level of hidden diversity, and the potential occurrence of further cryptic species. This diversity reflects the biogeographic past of Switzerland, and suggests that amphipods are ideally suited to address questions on endemism and adaptive radiations, post-glaciation re-colonization and invasion dynamics as well as biodiversity-ecosystem functioning relationships in aquatic systems.

Altermatt, F., Alther, R., Fišer, C., Jokela, J., Konec, M., Küry, D., Mächler, E., Stucki, P., & Westram, A. M. (2014). Diversity and Distribution of Freshwater Amphipod Species in Switzerland (Crustacea: Amphipoda). PLoS ONE, 9(10), e110328. https://doi.org/10.1371/journal.pone.0110328

Urbanisation has an important impact on biodiversity, mostly driving changes in species assemblages, through the replacement of specialist with generalist species, thus leading to biotic homogenisation. Mobility is also assumed to greatly affect species’ ability to cope in urban environments. Moreover, specialisation, mobility and their interaction are expected to greatly influence ecological processes such as metacommunity dynamics and assembly processes, and consequently the way and the spatial scale at which organisms respond to urbanisation. Here we investigate urbanisation impacts on distinct characteristics of species assemblages – namely specialisation degree in resource use, mobility and number of species, classified according to both characteristics and their combination – for vascular plants, butterflies and birds, across a range of spatial scales (from 1 × 1 km plots to 5 km-radius buffers around them).

We found that the degree of specialisation, mobility and their interaction, greatly influenced species’ responses to urbanisation, with highly mobile specialist species of all taxonomic groups being affected most. Two different patterns were found: for plants, urbanisation induced trait divergence by favouring highly mobile species with narrow habitat ranges. For birds and butterflies, however, it reduced the number of highly mobile specialist species, thus driving trait convergence. Mobile organisms, across and within taxonomic groups, tended to respond at larger spatial scales than those that are poorly mobile. These findings emphasize the need to take into consideration species’ ecological aspects, as well as a wide range of spatial scales when evaluating the impact of urbanisation on biodiversity. Our results also highlight the harmful impact of widespread urban expansion on organisms such as butterflies, especially highly mobile specialists, which were negatively affected by urban areas even at great distances.

Concepción, E. D., Moretti, M., Altermatt, F., Nobis, M. P., & Obrist, M. K. (2015). Impacts of urbanisation on biodiversity: The role of species mobility, degree of specialisation and spatial scale. Oikos, 124(12), 1571–1582. https://doi.org/10.1111/oik.02166

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.