Grazing practices shape the plant populations and communities of semi-natural grasslands, and the conservation of these ecosystems depends on maintaining traditional extensive grazing systems that have been in place for centuries, even millennia.
However, changes in practices linked to climate and socio-economic factors can lead to a loss of biodiversity, changes in vegetation, soil degradation and a reduction in ecosystem services.
This study published by Christel Vidaller and Thierry Dutoit in Agriculture, Ecosystems & Environment analysed the medium-term effects (3 to 16 years) of two methods of sheep grazing in southern France: traditional grazing over thousands of years with shepherds and dogs, and recent paddock grazing, which appeared at the beginning of the XXIᵉ century. Over six paired sites and three years of observations, vegetation, mesological data and plant traits were studied.
Although the five vegetation zones created by traditional grazing are still visible, paddock grazing has led to a medium-term homogenisation of the plant communities, marked by the expansion of xero-mesophilous species and the disappearance of the historical gradient of grazing intensity.
These results show the ecological impacts of grazing changes on biodiversity, ecosystem functioning and the long-term preservation of heritage grasslands, and provide indications for restoration strategies.
sustainable and adaptive in the face of environmental and socio-economic change.