Vittoz Pascal

Favourable wetlands for re-introduction of Saxifraga hirculus in Jura Mountains
Etude de marais favorables et défavorables à la réintroduction de Saxifraga hirculus dans le Jura


Project Number: CH-4953
Project Type: Master
Project Duration: 07/01/2010 - 05/31/2012 project completed
Funding Source: other ,
Leading Institution: Université de Lausanne
Project Leader: Dr. Pascal Vittoz
Maître d'enseignement et de recherche
Institut des dynamiques de la surface terrestre, IDYST
Université de Lausanne
Géopolis
1015 Lausanne
Phone: +41 (0) 24 692 43 67 ; +41 (0) 21 692 35 30
FAX: +41 (0) 21 692 35 05
e-Mail: pascal.vittoz(at)unil.ch
http://www.unil.ch/idyst

related to this project.
for which the project has a relevance.


Research Areas:
Biodiversity

Disciplines:
environmental sciences
soil sciences

Keywords:
Saxifraga hirculus, Jura Mountains, wetlands, phytosociology, bioindication, HISTOSOL, vascular plants, testate amoebae, bryophytes, paléoécology

Abstract:
In Switzerland as everywhere in Europe, the pressure on the land is extremely intense. Agricultural practices as well as other human activities disturb delicate zones such as fens, peat bogs poor grasslands or other rare and endangered ecosystems. These ecosystems often disappeared as a consequence of the disturbance they endured. Along with the rarefaction of this habitat the associated fauna and flora became rare or extinct. Saxifraga hirculus also known as Golden saxifrage is one of this species (vascular species) that live in fens, one of these rare endangered ecosystems.
S.hirculus is considered as a threatened species in Switzerland and in entire Europe. However, in the past this plant was more abundant. At the beginning of the 20th century, the species was found in more than twenty sites, located along the Jura and Prealp Mountains. Today, this plant is present only in a single fen located near the col du Marchairuz: le marais des Amburnex.
S. hiruclus is a species that lives in fens, ideally in spring fens. This species needs an environment with a high percentage of humidity, but it does not bear to be totally immerged. For this reason, this plant needs a high water table, and an important bryophytic carpet that preserves humidity. In addition, contrary to other species that live in the fen, S.hirculus roots in the lower level of the stratum of the bryophytic carpet, which makes it particularly vulnerable to high fluctuations in the water table.
The objectives of this work are divided into three parts: 1) the identification of favourable sites for the reintroduction of S. hirculus in the Jura, 2) the detailed definition of the ecology of this rare species with the use of different types of bioindicators and the comparison of their precision, 3) the paleoecological study using testate amoebae of sites where S. hirculus was present in the past. Three types of bioindicators were used to characterize and identify the fens that are most suitable for the development of S. hirculus: the vascular plants, bryophytes and testate amoebae.
The results suggest there are still favourable fens for the reintroduction of S. hirculus in the Jura Mountains. The number of favourable sites varies as a factor of the applied bioindicators. The community of testate amoebae reflect the environmental conditions more precisely than vascular plants. Based on the testate amoeba community, there are four fens that could be suitable for the reintroduction of S. hirculus.
On the basis of the paleoecological study of the fens, it was not possible to explain entirely the disappearance of S. hirculus. However, this study gave an insight into the past ecological conditions and the general evolution of the different fens. It laid a ground work for using testate amoeba to identify suitable fens for a future reintroduction of S. hirculus.

Leading questions:
Is it possible to find wetlands in Jura Mountains with favourable ecological conditions for the re-introduction of the endangered Saxifraga hirculus?

Publications:
Arnet T. (2012). Etude de marais favorables et défavorables la réintroduction de Saxifraga hirculus dans le Jura. Travail de master, Universités de Neuchâtel et Lausanne, 84 p. + annexes.
pdf Master


Last update: 5/18/18
Source of data: ProClim- Research InfoSystem (1993-2024)
Update the data of project: CH-4953

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