The EU Green Infrastructure Strategy aims to help stop biodiversity loss and enable ecosystems to deliver their services to people. Natural and semi-natural areas of Chernihiv (Ukraine) represents the green infrastructure of an average-sized Eastern European city in the continental biogeographical region. In total, 93 decorative species and forms of tree and shrub plants are used for the city landscaping, and 18 of them are invasive. As such, there is a need to develop sustainable approaches to control the spread of alien plants. For this purpose, the invasive plant species' ecological strategies were investigated.
According to the classification of J.P. Grime (1988, 2006), the decorative cultivated plants of invasive species belong to three categories: сompetitors (C-strategists: Robinia pseudoacacia), stress tolerators (S-strategists: Acer saccharinum, Caragana arborescens, Cotinus coggygria, Gleditsia triacanthos, Fraxinus pennsylvanica, Juglans mandshurica, Physocarpus opulifolius, Ptelea trifoliate, Quercus rubra, Rhus typhina, Sorbaria sorbifolia) and ruderal plants (R-strategists: Acer negundo, Amorpha fruticosa, Prunus virginiana, Prunus serotina, Robinia viscosa, Ulmus pumila).
Robinia pseudoacacia causes the greatest danger to the phytodiversity of green infrastructure. Black locust–pine and black locust–birch phytocenoses are formed as a result of black locust's invasion in anthropogenically disturbed forests. They differ in structure and species composition. S-strategists do not pose a threat to the city’s green infrastructure biodiversity. They play an important role in preventing erosion processes in sloping areas. R-strategists are pioneer species in anthropogenic areas (e.g., wastelands, roadsides and railroad tracks) and recreationally disturbed forest and grassland ecosystems. They are characterized by rapid growth, high generative and vegetative productivity, and the ability to spread over long distances.
Our research confirmed the results of previous studies that demonstrated that significant tolerance to the environmental gradients (temperature, soil moisture and salinity, light availability, resistance to pests), high reproductive ability, growth rate and native latitudinal range determine the ecological strategy of invasive plants.
