Skip to Main content Skip to Navigation
Theses

Etude des mares du parc Naturel Régional des Causses du Quercy : fonctionnement, biodiversité et connectivité inter-mares. Propositions pour l'entretien et la sauvegarde.

Abstract : In the arid karstic region of the “Causses du Quercy” (SW France), ponds constitute the only available surface water resource on this limestone plateau.
As the natural evolution of ponds leads to the filling up of these ecosystems, a comparative study of three ponds at various stages of succession showed the evolution of abiotics parameters (temperature, oxygen concentration...) as a function of stages of succession. Concurrently, ponds varied in terms of plant and animal species richness. Each pond supported a distinctive fauna and took part in the global biodiversity of these ecosystems.
At a larger scale, thirty ponds where studied to investigate factors affecting the distribution of fauna in a pond network. We identified 230 species of invertebrates and 6 species of vertebrates. Results do not permit to draw up a typology of ponds or to highlight characteristics communities of these ponds. As ponds surrounded by terrestrial landscape constitute “islands” for the aquatic fauna, five taxonomic groups were chosen based on their
different capabilities of dispersion to study the species distribution: Odonata, Coleoptera, Amphibia, Mollusca and Oligochaeta. For Odonata, pond area influence species distribution. For amphibia, forested ponds are more likely to include all the species. For both Mollusca and Oligochaeta, the passive dispersers, the results indicate that the species distribution is a randomised distribution. For Coleoptera, the distribution is not a randomised distribution but we do not find the factors which could explain this distribution.
Then, we used the capture-mark-recapture technique in order to estimate the degree of linkage in three patchy populations of odonate localised on three ponds. We demonstrated that three factors influence the dispersal ability of these odonates: abiotic factors (especially weather conditions), interspecific differences (sensitivity to weather conditions, species size and behaviour), intraspecific characteristics (sex and age).
This study underlines the role of ponds in the biodiversity of the study area and the role of pond network and of the temporal evolution of these ponds in the maintenance of this biodiversity. Results are discussed in order to propose management plans to maintain the biodiversity of these ecosystems.
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00259814
Contributor : Sandrine Angélibert <>
Submitted on : Friday, February 29, 2008 - 2:20:04 PM
Last modification on : Friday, January 10, 2020 - 9:08:37 PM
Long-term archiving on: : Friday, November 25, 2016 - 9:29:02 PM

Identifiers

  • HAL Id : tel-00259814, version 1

Collections

Citation

Sandrine Angélibert. Etude des mares du parc Naturel Régional des Causses du Quercy : fonctionnement, biodiversité et connectivité inter-mares. Propositions pour l'entretien et la sauvegarde.. Ecologie, Environnement. Université Paul Sabatier - Toulouse III, 2004. Français. ⟨tel-00259814⟩

Share

Metrics

Record views

1379

Files downloads

1854