Multi-year monitoring of Asclepias syriaca L. spread in the Deliblato sands protected reserve in Serbia

Abstract

The invasion of non-native plant species has a detrimental effect on native biodiversity. In a seven-year research project, we investigated the occurrence of the invasive species Asclepias syriaca L.in the Deliblato Sands protected area, located at a south-eastern part of the Pannonian Plain, and identified the factors that contribute significantly to its colonisation. The distribution of this invasive species was monitored on more than 300 km of the accessory, bordering and selected internal roads. A. syriaca occurs within the protected area but is much more widespread on accessory and bordering roads. The number of locations of A. syriaca increased every year of the study, even within the protected area, indicating a further spread of this species. A. syriaca is much more abundant on the north-eastern edge than in the south-west. The reason for this is most likely the much larger area of abandoned agricultural land in the north-east. Roads used for public transport are the main entry points for the further spread of A. syriaca. In contrast, recreational trail use does not enhance the spread in the Deliblato Sands natural reserve. This study can be used to further analyse the ecological dynamics of A. syriaca and to develop timely strategies by which to prevent or slow down its spread.