title: High Stocking Density Controls Phillyrea Angustifolia in Mediterranean Grasslands.
abstract: Extensive grazing applied in the form of low instantaneous pressure over a long period is a widespread management practice in protected areas. However this kind of stocking method does not always achieve the expected results, in particular because it fails to limit colonization by woody plants.This is the case in the relict xero-halophytic grasslands of the northern Mediterranean coastal region, subjected to widespread colonization by the shrub Phillyrea angustifolia despite the presence of extensive grazing. In this study, we investigated, for an equal annual stocking rate, the respective impact of high stocking density applied over a short period (mob grazing) and low stocking density applied over a long period on both P. angustifolia and herbaceous cover, using an in situ experimental design run for 7 years. Only mob grazing was effective both in controlling the establishment and increasing the mortality of P. angustifolia individuals. We did not find any difference after the 7 years of experimentation between the two stocking methods with regard to the herbaceous community parameters tested: species richness, diversity, evenness, contribution of annual characteristic species. By contrast, the exclusion of domestic grazing led to a strong reduction of these values.The use of mob grazing may be well suited for meeting conservation goals such as maintaining open habitats in these grasslands.
authors.affiliation: Institut de recherche de la Tour du Valat, Le Sambuc, Arles, 13200, France. mesleard@tourduvalat.org.|Institut Méditerranéen de Biodiversité et d'Ecologie (IMBE), UMR CNRS IRD, Avignon Université, Aix Marseille Université, 337 chemin des Meinajariés, Site AGROPARC BP 61207, Avignon cedex 09, F-84911, France. mesleard@tourduvalat.org.
authors.forename: François
authors.initials: F
authors.lastname: Mesléard
authors.affiliation: Institut de recherche de la Tour du Valat, Le Sambuc, Arles, 13200, France.
authors.forename: Nicole
authors.initials: N
authors.lastname: Yavercovski
authors.affiliation: Institut de recherche de la Tour du Valat, Le Sambuc, Arles, 13200, France.
authors.forename: Gaétan
authors.initials: G
authors.lastname: Lefebvre
authors.affiliation: Institut de recherche de la Tour du Valat, Le Sambuc, Arles, 13200, France.
authors.forename: Loic
authors.initials: L
authors.lastname: Willm
authors.affiliation: CNRS, UMR6553 Ecosystèmes Biodiversité Evolution, Campus de Beaulieu, Rennes, F-35042, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Bonis
mesh_terms: D000818:Animals; D044822:Biodiversity; D017753:Ecosystem; D065948:Grassland; D060434:Herbivory; D019083:Mediterranean Region; D029592:Oleaceae / Q000254:growth & development*
keywords: Extensive grazing; Mediterranean grassland; Mob stocking; Phillyrea angustifolia; Stocking density; Woody colonization