Evaluation der Ökomassnahmen: Bereich Biodiversität

1993 führte der Bund ökologische Direktzahlungen ein; seit 1999 ist die Erbringung des ökologischen Leistungsnachweises (ÖLN) durch die Landwirtschaftsbetriebe die Voraussetzung zum Bezug von Direktzahlungen. Heute werden 97 % der landwirtschaftlichen Nutzfläche nach den Regeln des ÖLN bewirtschaftet. Die wichtigste Massnahme des ÖLN, welche einen Einfluss auf die Biodiversität hat, ist, dass die Betriebe 7 % ihrer landwirtschaftlichen Nutzfläche (LN) als ökologische Ausgleichsflächen (öAF) auszuweisen haben (bei Spezialkulturen 3,5 %). Weitere Anforderungen des ÖLN (ausgeglichene Nährstoffbilanz, geregelte Fruchtfolge, Bodenschutz, gezielter Einsatz von Pflanzenschutzmitteln, tiergerechte Haltung der Nutztiere) können ebenfalls einen Einfluss haben, stehen jedoch weniger im Vordergrund

Efficacy of three strategies based on insecticide, oil and elicitor treatments in controlling aphid populations and potato virus Y epidemics in potato fields

Potato virus Y (PVY), the potato virus with the highest economic impact in Europe, is transmitted by aphids in a non-persistent manner. A two-year field experiment was conducted in Switzerland to evaluate the efficacy of three strategies for controlling aphid populations and the spread of PVY, consisting of treatment with one insecticide (Karate Zeon®), one elicitor (Bion®) and one oil (Telmion®), respectively. The elicitor strategy proved to be ineffective for controlling aphid populations and inadequate for controlling PVY spread. The insecticide strategy gave incomplete protection from aphid infestations, owing to the selection of aphid-resistant clones. The insecticide gave too little protection against PVY spread for it to be considered a suitable candidate for the purpose. The oil strategy had no effect on aphid populations, but was the best option to reduce PVY spread. © 2013 Blackwell Verlag GmbH

Effect of low-input habitats on biodiversity in Swiss agricultural landscapes

Since 1993 Swiss farmers increasingly convert land to low-input habitats, these ecological compensation areas (ECA) making up today 10% of the Utilised Agricultural Area. To assess whether ECA introduction allows enhancing agro-biodiversity, biodiversity indicators are monitored in the Swiss Plateau. ECA had higher diversity of plant, bird, and arthropod species. However, in some ECA meadows and traditional orchards, the composition of the vegetation still reflected their former intensive management. It is concluded that faunistic indicators react more rapidly to the introduction of ECA than the vegetation

Highly energetic rockfalls: back analysis of the 2015 event from the Mel de la Niva, Switzerland

International audienceProcess-based rockfall simulation models attempt to better emulate rockfall dynamics to different degrees. As no model is perfect, their development is often accompanied and validated by the valuable collection of rockfall databases covering a range of site geometries, rock masses, velocities, and related energies that the models are designed for. Additionally, such rockfall data can serve as a base for assessing the model's sensitivity to different parameters, evaluating their predictability and helping calibrate the model's parameters from back calculation and analyses. As the involved rock volumes/masses increase, the complexity of conducting field-test experiments to build up rockfall databases increases to a point where such experiments become impracticable. To the author's knowledge, none have reconstructed rockfall data in 3D from real events involving block fragments of approximately 500 metric tons. A back analysis of the 2015 Mel de la Niva rockfall event is performed in this paper, contributing to a novel documentation in terms of kinetic energy values, bounce heights, velocities, and 3D lateral deviations of these rare events involving block fragments of approximately 200 m 3. Rockfall simulations are then performed on a "per-impact" basis to illustrate how the reconstructed data from the site can be used to validate results from simulation models

Examine (Exploitation of aphid monitoring in Europe) : an E.U. thematic network for the study of global change impacts on aphids

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EXAMINE (EXploitation of Aphid Monitoring In Europe) : an European thematic network for the study of global change impacts on aphids

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Environmental change, life cycle traits and aphid phenology

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