Impacts of drought stress on water relations and carbon assimilation in grassland species at different altitudes

Grassland is an important ecosystem type which is not only used agriculturally, but also covers sites which cannot be used for other purposes, e.g. in very steep locations or above timberlines. Prolonged summer droughts in the mid-term future, as are predicted for Central Europe, are expected to have a major impact on such ecosystems. To address this topic, rainfall exclusion via shelters was performed on three grassland sites at different altitudes (393, 982 and 1978 m above sea level) in Switzerland. Diurnal drought treatment effects were studied at each study site on a completely sunny day towards the end of an 8–10 week shelter period. Ecophysiological parameters including gas exchange (An, gs and intrinsic WUE) and chlorophyll a fluorescence (Fv/Fm, ΦPSII and NPQ) were considered for several species. The lowland and the Alpine field site were more strongly affected by soil drought than the pre-Alpine site. At all sites, grasses showed different patterns of reductions in stomatal conductance under soil drought compared to legumes and forbs. In addition, grasses were significantly more affected by reductions in assimilation rates at all sites. Time courses of reductions in assimilation rates relative to controls differed between species at the Alpine site, as some species showed reduced assimilation rates at this site in the early morning. Thus, similar rainfall exclusion treatments can trigger different reactions in various species at different sites, which might not become obvious during mere midday measurements. Overall, results suggest strong impacts of prolonged summer drought on grassland net photosynthesis especially at the Alpine site and, within sites, for grasses

Sport as a means of immigrant youth integration: An empirical study of sports, intercultural relations, and immigrant youth integration in Switzerland

Der Beitrag geht der Bedeutung des Sports für die Integration von jugendlichen Einwanderern in die Aufnahmegesellschaft nach. Aufgrund von Daten einer Querschnittstudie bei 454 Jugendlichen der ersten Einwanderergeneration aus Gymnasien, Berufsschulen und Vorlehreeinrichtungen der deutschen Schweiz zeigen unsere Ergebnisse, dass der Sport für die meisten Jugendlichen mit Migrationshintergrund ein wichtiger Teil ihrer Freizeit darstellt, auch wenn der Anteil von Migrantinnen, die Mitglied eines Sportvereins sind, im Vergleich zu Migranten zweimal niedriger ausfällt. Zudem haben sowohl männliche wie weibliche Jugendliche mit Migrationshintergrund, die Sport in einem Sportverein ausüben, deutlich mehr persönliche Kontakte mit Schweizer Peers während ihrer sportlichen Aktivitäten. Jugendliche, die von häufigen persönlichen Kontakt mit Schweizer Peers im Sport berichten, haben auch deutlich mehr interkulturelle Kontakte in ihrer Freizeit generell und innerhalb des Kreises ihren engsten Freunde. Schließlich vermögen häufige Kontakte mit Schweizer Peers im Sport das Gefühl der jugendlichen Einwanderer, in der Schweiz integriert zu sein, zu erhöhen.