Abstract
The presence of alien plant species in disturbed habitats is a well-studied subject, however, the contribution of wind farm projects to alien plant invasion is often overlooked in environmental impact assessment. The present study tests a survey method for the assessment of plant diversity and the detection of alien plant invasion in two wind farm areas in Romania. Over 5 years, we recorded plant species incidence data in disturbed and undisturbed plots, making one visit per growing season each year. Using several plant community indicators and methods, such as species richness, beta diversity, non-metric multidimensional scaling, and multinomial species classification, we reliably detected plant species assemblage, including 26 alien plant species among the 608 recorded. Disturbed plots harbor a higher number of alien plant species, supporting the hypothesis that disturbances caused by wind farms reduce habitats' resilience to alien plant invasions. Despite the presence of habitat specialist plant species in certain plots, the community of alien plants did not show a clear preference for disturbed or undisturbed plots. The results underscore the importance of surveying the wind farms beyond the disturbed sites through regular monitoring to accurately assess their impact on plant diversity and detect alien plant invasions. The regular monitoring of all plant species during growing seasons will provide useful data for informing conservation strategies for native plants, including the control and eradication of alien species in early invasion stages.