The structure of earthworm communities in urbanised biotopes of the Central Polissia

The article describes the results of the impact of urbanisation on the quantitative and qualitative structure of earthworm communities, since urbanisation is currently one of the main threats to biodiversity. Earthworms, as the most common representatives of the edaphic mesofauna, react sensitively to the level of environmental pollution. On the example of the city of Cherniakhiv, it has been established that the lumbricide fauna of the studied area includes eight species: Aporrectodea caliginosa (Savigny, 1826), A. rosea (Savigny, 1826), A. trapezoides (Dugesi, 1828), Lumbricus terrestris (Linnaeus, 1758), L. castaneus (Savigny, 1826), Octolasion lacteum (Örley, 1885), Eisenia fetida (Savigny, 1826), and Dendrobaena octaedra (Savigny, 1826). All detected worms are rather unevenly represented in the analysed samples. Background species in the study area are A. caliginosa, A. rosea, and L. terrestris. According to the analysis of the relative abundance in the samples, A. caliginosa is dominant, whereas A. rosea and O. lacteum are less common. According to the results of the spatial distribution of earthworms, a clear dominance of one species was noted in agrocoenoses and in areas with a significant recreational load, whereas in a less anthropogenically transformed zone a higher number and species diversity of lumbricides was noted. Using cluster analysis of k-means according to biodiversity estimates, two clusters of samples were selected. At the same time, such parameters as the number of species, the number of individuals in the sample, and the Brillouin index make the greatest contribution to the differentiation of clusters. A reliable correlation was found between the number of individuals in the sample and the reflectivity in the B8 band range, as well as between the indicator of the evenness of the grouping structure and the reflectivity in the B4, B5, B11, and B12 bands of the Sentinel-2 space image and the value of the NDVI vegetation index. These spectral characteristics were used to model the spatial distribution of the absolute number of lumbricides and the evenness of their groups. The model of the spatial distribution of the number of earthworms has a mosaic character: individual cells with a high number of lumbricides are replaced by areas where they are less abundant. There is a certain relationship between individual estimates of earthworm biodiversity and land cover spectral characteristics.