DRIVERS OF MULTIPLE PLANT INVASION

The Ukrainian Carpathian Mountains are home to Europe’s last great wilderness areas and to the greatest remaining old-growth and virgin forests. Pristine habitats at higher elevations, including old-growth forests, are however experiencing increased levels of invasion by alien plant species established for over a century in the adjacent lowlands. Under climate change, flooding is projected to become more frequent in the Carpathians, while increasing pressures from forestry and tourism are altering habitats, including in protected areas. Funded by a BES Large Grant, we have jumpstarted a long-term monitoring project to understand what drives successful multiple invasion, in particular how demographic traits (dispersal, reproduction, growth), and interactions among invaders and native species may affect establishment of invaders under global change. 

Research questions 

• What is the role of flooding in promoting the establishment of stable local populations of multiple invaders? 
• Are interactions among invaders exacerbating the effect of human pressures and natural disturbances on multiple-invasion? 
• What is the relative importance of species demographic traits on successful invasion? 
• How important are interactions of biotic and abiotic effects in future invasion dynamics?

We have established systematic monitoring of local patch dynamics of invaders, where we survey the number of recruits and density (i.e., number and canopy cover) of adults of invaders and native woody and herbaceous plants in 140 plots. The plots are located in sites where high invasion potential (network of rivers and roads, proximity to human settlements, and nearby established population of invaders) meets high biodiversity (a high proportion of old-growth forests and meadows of conservation value; within or in close proximity to protected areas); and invasion is therefore likely to have particularly negative impacts. 

The plots are in two different habitat types, meadow or forest, either along riparian corridors or outside these corridors. We were lucky to secure a PhD student, Matt Clements, in collaboration with the University of Sheffield to lead the analyses for the next 3-4 years.

Engagement with stakeholders and the general public has been at the core of this project. Based on TV presentation, videos and articles in newspapers, the project reached over 700.000 people in Ukraine. A summary of the engagement can be found here.

Outreach was aimed at raising Ukrainians' awareness about the causes and consequences of the spread of invasive species. For two years now, as a result of Russian aggression, Ukrainians are going through a challenging period. Even though the maximum efforts of Ukrainians today are directed toward survival, we want to emphasise that the issue of environmental protection has not lost its relevance even in such a challenging period. Against the background of the terrible destruction of natural values in the combat zone, Ukrainians strive to preserve these natural values, which are relatively safe, far from the combat zone.

UPDATE: Despite the Russian invasion of Ukraine and the ensuing war, we managed to proceed with the monitoring of the 50 % of the plots in summer 2022 and will resume monitoring of all plots in 2023. This has provided an invaluable income opportunity for local researchers who have suffered hardships this past year. And we believe that establishing a long-term conservation-driven collaboration with UA researchers is more important than ever. Our first results are also in, suggesting widespread increase in density of invaders in riparian habitats.

Although the Carpathian Mountains are not direct targets of the invasion of Ukraine by Russian forces, most people there, including my collaborators from Danube Carpathian Programme, are hit by hardship and dedicate substantial time to humanitarian work. 

If you like to support the Danube Carpathian Programme, please consider a donation.