The effect of landscape structure and habitat quality on the occurrence of Geranium sylvaticum in fragmented hay meadows

Abstract

In this study, 119 meadows distributed across the Yorkshire Dales National Park were re-surveyed and changes in the overall vegetation and the landscape structure over the last two decades were investigated with a particular emphasis on the influence of management practices. To study the effects of fragmentation on a particular species, this study focused on changes in the occurrence of the perennial herb Geranium sylvaticum as this is accepted as an indicator of the good ecological condition of British upland hay meadows. Results indicated that there has been a general impoverishment in the vegetation with a decrease in diversity, species richness and habitat quality and meadows have become 10 times more isolated than 20 years ago. Habitat quality was positively associated with agri-environment schemes that encourage extensive management practices, low grazing intensity and organic fertiliser application. G. sylvaticum has disappeared from 40% of the fields where it used to be and its occurrence was influenced by habitat quality and the connectivity of the fields in 2003. For perennial plants that do not have specialised reproduction and dispersal mechanisms like G. sylvaticum, changes at the local scale may have stronger effects on survival than changes at the wider landscape scale. It is thus of utmost importance to maintain and encourage traditional management practices in remaining hay meadows, especially hay making practices that would facilitate the exchange of seeds between fields and improve landscape connectivity.