Human activity is affecting and transforming the natural environment, changing the ecosystem mosaic and natural biogeochemical processes in urban-industrial landscapes. Among the anthropogenic ecosystems, there are many present features of Novel Ecosystems (NE), e.g., the de novo created habitats on post-mineral excavation sites. The biological nature of the functional mechanisms of Novel Ecosystems is mostly unknown. In natural and semi-natural ecosystems, biodiversity is considered as the primary element influencing ecosystem processes and functioning. The preliminary studies conducted on post-mineral excavation sites have shown that, in poor oligotrophic habitats, the species composition of the assembled vascular plants is non-analogous, distinctive, and not found in natural and semi-natural habitats. This paper aims to present the gaps between scientific identification of the biological mechanisms driving ecosystem processes and functioning (including the expanding areas of Novel Ecosystems created de novo). Among the identified gaps, the following issues should be listed. The detailed identification and understanding of the processes and biodiversity-dependent functioning of Novel Ecosystems is crucial for proper environmental management, particularly when facing the challenges of ecological constraints and of global change. The ecology of Novel Ecosystems is a social and economic issue because of the relationships with densely populated urban-industrial areas.

The primary producers and processes of matter and energy flow, reflected by the soil enzyme activity, are the basics of all ecosystem functioning processes. This paper reviews the relationships between the plant diversity, the physicochemical substrate parameters, and the soil enzymatic activity in novel ecosystems of the urban–industrial landscape, where the factors driving soil enzyme activity are not fully understood and still need to be studied. The relationship between the biotic and abiotic factors in the development of novel ecosystems on de novo established habitats, e.g., sites of post-mineral excavation, are shaped in ways unknown from the natural and the semi-natural habitats. The main criteria of de novo established ecosystems are the vegetation patches of the non-analogous species composition created as a result of human impact. The non-analogous species assemblages are associated with different microorganism communities because the biomass and the biochemistry of soil organic matter influence the enzyme activity of soil substrates. Moreover, the soil enzyme activity is an indicator that can dynamically reflect the changes in the microbial community structure dependent on the best-adapted plant species, thanks to the particular traits and individual adaptive adjustments of all the plant species present. This way, soil enzyme activity reflects the sum and the interactions of the elements of the ecosystem structure, irrespective of the vegetation history and the habitat origin.

Wetlands represent a small proportion of all habitats. Still, they are very important features within the landscape, particularly in the ecosystem mosaic. They are composed of many specifically adapted organisms. Wetlands spontaneously establish and provide a significant source of heterogeneity...

(1): The Upper Silesia region of Poland is one of the most extensively altered regions of Europe due to human activity, especially coal mining. (2): We used cluster analysis to examine the floristic composition of three classified forest communities: forests developed on post-coal mine mineral heaps (HF), mixed deciduous forests (DECI), and managed secondary coniferous forests (CON). Vegetation data were collected from 44 randomly selected plots, and plant traits connected with persistence, dispersal, and regeneration were taken from commonly used plant trait databases. (3): Higher species richness, species diversity, and evenness (36, 2.7, and 0.76, respectively) were calculated for HF plots compared with those plots from DECI (22, 1.9, and 0.62) and CON (18, 2.0, and 0.71) plots. Higher functional richness (0.173, 0.76) and functional divergence were determined for HF compared with those calculated for DECI (FRic 0.090, FDiv 0.71) and CON (FRic 0.026, FDiv 0.69). In contrast, the substrate from HF forests had significantly lower soil respiration (0.76 mg-CO₂ h/m²) compared with substrates from both CON and DECI forests (0.90 and 0.96 mg-CO₂ h/m², respectively); (4): A set of complex abiotic stresses which plants suffer from on coal mine spoil heaps shaped different patterns of taxonomic and functional diversity. These findings demonstrate the importance of investigating successional aspects and carbon dynamics of de novo forests which have developed on post-coal mine spoil heaps in urban industrial areas.

Long-term exploitation of mineral resources has significantly changed the natural environment in urban-industrial landscapes. The changes on the surface of the extraction sites as a consequence of excavation of mineral resources provide specific mineral oligotrophic habitats on which plant species and thus vegetation can establish spontaneously. Some of these sites fulfill the prerequisites of novel ecosystems. This study was conducted on the spontaneous vegetation of post-extraction sites. Lists of species spontaneously covering these sites were prepared based on published data and our own records. This research revealed that species composition and vegetation types vary in time. These post-extraction novel ecosystems are also important for the presence of rare, endangered, and protected species noted in patches of different vegetation types. The variety of habitat conditions provided by these sites facilitates the occurrence of a wide spectrum of plants (both in terms of their socio-ecological origin and their ecological spectrum). This research proves how important these post-extraction novel ecosystems are for supporting plant and vegetation diversity in urban-industrial landscapes. Enhancing the biodiversity significantly increases the ecosystem services delivered by these sites and also the functioning of entire ecosystems. These natural processes on human habitats are essential in urban-industrial ecosystem landscape mosaics.

Abandoned railway areas are places for the spontaneous spread of plants and the formation of specific plant communities. However, only limited information on this subject is available in the literature. The study aimed to determine the direction and the rate of forest formation, taking into account selected environmental factors. A floristic, phytosociological, and soil survey was carried out on a set of abandoned railway lines in the Silesia Province (southern Poland). For this purpose, 30 plots of vegetation were selected: 15 located in the vicinity of forests (F) and 15 surrounded by ruderal or segetal communities (NF). As a result, a total of 132 species (121 vascular plants and 11 mosses) were recorded, including 83 species at F plots and 78 species at NF plots. During the research, 13 syntaxa were distinguished. It was found that silt content, nitrate nitrogen (N-NO₃), pH, and phosphorous have a significant impact upon which species dominated in the surveyed areas. It was found that the proximity of the forest was a crucial factor in determining the development of forest communities on abandoned railway areas. These results can be helpful for understanding how environmental conditions shape the forest structure on these types of habitats.