Haute Ecole pédagogique Fribourg

Entrée dans l’écrit à l’école enfantine fribourgeoise

Ansen Zeder, Elisabeth ; Joye-Wicki, Christiane

Les auteures ont recueilli, en automne 2010, auprès de 20 enseignant-e‐s de l’école enfantine du canton de Fribourg (Suisse), leurs pratiques déclarées sur l’Entrée dans l’Ecrit. Leurs représentations pédagogiques et les théories implicites sous-­jacentes sont examinées. Le rapport s’appuie sur les entretiens semi-directifs de 45 à 60 minutes, réalisés auprès de 20...

Université de Fribourg

Insect and mollusc communities in wildflower strips : effects of plant diversity and surrounding landscape in an agro-ecosystem

Fabian, Yvonne ; Bersier, Louis-Félix (Dir.)

Thèse de doctorat : Université de Fribourg, 2013 ; no. 1780.

Fast 38% der Landfläche unserer Erde wird landwirtschaftlich genutzt. Ihr Beitrag zur Biodiversität ist deshalb wichtig für den Umweltschutz. Wenn landwirtschaftliche Flächen nachhaltig genutzt werden, können sie zu einer hohen Diversität beitragen, was sich positiv auf sogenannte Ökosystemleistungen wie Bestäubung und biologische Schädlingsbekämpfung auswirkt. Die Identifizierung von...

Université de Fribourg

Differential effects of historical migration, glaciations and human impact on the genetic structure and diversity of the mountain pasture weed Veratrum album L.

Treier, Urs A. ; Müller-Schärer, Heinz

In: Journal of Biogeography, 2011, vol. 38, p. 1- 16

Aim Today’s genetic population structure and diversity of species can be understood as the result of range expansion from the area of origin, past climatic oscillations and contemporary processes. We examined the relative importance of these factors in Veratrum album L., a toxic weed of mountain grasslands.Location Continental Europe.Methods Forty...

Université de Fribourg

Sawdust addition reduces the productivity of nitrogen-enriched mountain grasslands

Spiegelberger, Thomas ; Müller-Schärer, Heinz ; Matthies, Diethart ; Schaffner, Urs

In: Restoration Ecology, 2008///10.1111/j.1526-100X.2008.00424.x

Anthropogenic nutrient enrichment of mountain grasslands has boosted grasses and fast-growing unpalatable plants at the expense of slow-growing species, resulting in a significant loss in biodiversity. A potential tool to reduce nutrient availability and aboveground productivity without destroying the perennial vegetation is carbon (C) addition. However, little is known about its suitability...

Université de Fribourg

Seed bank persistence of clonal weeds in contrasting habitats: implications for control

Hesse, Elze ; Rees, Mark ; Müller-Schärer, Heinz

In: Plant Ecology, 2007, vol. 190, no. 2, p. 233-243

The ability of weeds to form a seed bank is important for their population dynamics and management because it provides a refuge enabling reinvasion after established target plants have died. However, knowledge of the differential seed behaviour of individual species over multiple years and varying environmental conditions is surprisingly rare but necessary for effective control of diverse weed...

Université de Fribourg

Land use, soil nutrient availability and conservation of biodiversity on mountain grasslands

Spiegelberger, Thomas ; Müller-Schärer, Heinz (Dir.)

Thèse de doctorat : Université de Fribourg, 2006 ; Nr. 1512.

Weltweit geht der Artenreichtum mit nie zuvor gesehener Geschwindigkeit zurück. In Europa sind viele traditionell bewirtschafteten Berggebiete noch artenreich, aber eine Verschiebung von der traditionellen, extensiven Nutzung zu einer intensiveren Nutzung von gut zugänglichen Gebieten und eine schrittweise Aufgabe von abgelegenen Flächen bedroht diese Habitate. In beiden Fälle könnte sich...

Université de Fribourg

Scale-dependent effects of land use on plant species richness of mountain grassland in the European Alps

Spiegelberger, Thomas ; Matthies, Diethart ; Müller-Schärer, Heinz ; Schaffner, Urs

In: Ecography, 2006, vol. Volume 29, p. 541-548

Traditionally managed mountain grasslands in the Alps are species-rich ecosystems that developed during centuries of livestock grazing. However, changes in land use including fertilisation of well accessible pastures and gradual abandonment of remote sites are increasingly threatening this diversity. In five regions of the Swiss and French Alps we assessed the relationship between land use, soil...

Université de Fribourg

The relation between unpalatable species, nutrients and plant species richness in swiss montane pastures

Kleijn, David ; Müller-Schärer, Heinz

In: Biodiversity and Conservation, 2006, p. online first

In agriculturally marginal areas, the control of unpalatable weeds on species rich pastures may become problematic due to agricultural and socio-economic developments. It is unclear how increased dominance of unpalatable species would affect the botanical diversity of these grasslands. We investigated whether there was any relationship between plant species diversity and the abundance of...