GREEN ROOFS AS URBAN ECOSYSTEMS FOR POST-INDUSTRIAL NOVEL ECOSYSTEMS' VEGETATION

Abstract

We present a study on the responses of plants from three functional groups: grasses, forbs, and legumes, deriving from a coal mining waste heap, to changes in environmental stress factors. The aim of this work is to identify plant responses to environmental stress resulting from the transfer of plants from the waste heap to the waste substrate and an extensive green roof with a thickness of 15 cm. After one year of growth, selected functional traits were analysed: including height, specific leaf area (SLA), and chlorophyll a content. The research aimed to understand the potential use of plants from the mine spoil heap - novel ecosystem, in creating green roofs by integrating them into the city's green infrastructure. The results showed that representatives of all studied plant groups responded to transplantation by changing their chlorophyll a content. Legumes additionally showed a change in SLA values. Therefore, grasses, when introduced to substrates with limited thickness compared to the waste heap substrate, exhibited the highest level of activation of processes that enhance green roof colonization by increasing chlorophyll a content, leading to growth. This intensification of photosynthetic processes serves as the basis and outcome of enhancing the colonization process of green roofs. The article concludes that plants growing on post-mining waste heaps show adaptations to the conditions of urban infrastructure and green roofs can constitute new ecosystems in the city.