Skip to Main content Skip to Navigation
Theses

Mécanismes de développement de lhétérogénéité du couvert végétal dans une prairie pâturée par des ovins

Florence Garcia
Abstract : Extensive management of grassland is an alternative way of abandoning certain areas, but it leads to a spatio-temporal heterogeneity of sward, both in quality and quantity. Our aim was to determine how animal behaviour and sward dynamic would explain the development of this heterogeneity and its spatial organisation. We analysed this development of heterogeneity in relation with intake and behaviour of animals, by making ewes graze continuously two cocksfoot swards at either a high or a low stoking rate (experiment 1). The ewes modified their behaviour at bite and feeding station scales and adapted their movements between patches so as to maximize their diet quality. From ear emergence grazing paths were not randomly performed and were organized around a specific scale of 5 meters. From flowering, on sward with low stocking rate, this behaviour led to a positive feedback resulting in a more frequent grazing of the best quality patches. Sward variability was organised at a macro and micro-heterogeneity, but no specific scale of spatial organization could be identified. We then analysed the role of grazing severity and frequency on sward differentiation and sheep preferences between swards (experiment 2). Sward differentiation was mainly influenced by the overall grazing pressure. Sheep preferences were explained by the relative abundance of green leaves in swards and by grazing frequency. Results are discussed in both a temporal and spatial perspectives and in relation with theoretical models of sward heterogeneity development.
Document type :
Theses
Complete list of metadatas

https://pastel.archives-ouvertes.fr/tel-00005715
Contributor : Admin Pastel <>
Submitted on : Monday, April 5, 2004 - 5:53:05 PM
Last modification on : Friday, October 23, 2020 - 4:47:51 PM
Long-term archiving on: : Friday, April 2, 2010 - 9:07:03 PM

Identifiers

  • HAL Id : tel-00005715, version 1

Collections

Citation

Florence Garcia. Mécanismes de développement de lhétérogénéité du couvert végétal dans une prairie pâturée par des ovins. Sciences de la Terre. INAPG (AgroParisTech), 2003. Français. ⟨NNT : 2003INAP0012⟩. ⟨tel-00005715⟩

Share

Metrics

Record views

239

Files downloads

667