Soil nematode communities in the subcrown space of Siberian larch Larix sibirica Ledeb., both cultivated in botanical gardens and growing in natural forests were studied and compared between each other. The results exhibited significant variations in total nematode abundance at all locations, with both extremely low and high values. The taxonomic diversity of nematodes was higher in the soil under larch in natural forests compared to that in botanical gardens. The larch forest within its range (Altai Republic) distinguished by the high taxonomic diversity of nematodes and highest number of specific taxa (nine genera vs. one to three at other points) among all locations. An increase in the relative abundance of plant parasites in the soil under trees cultivated in botanical gardens, as well as nematodes associated with plants under naturally growing larch, were observed in the ecotrophic structure of nematode communities. The evaluation of ecological indices (SI and EI) revealed the presence of transformed soil ecosystems in the subcrown space of larch trees cultivated in botanical gardens. Also, a statistically significant relationship between soil pH and the nematode community maturity index was found. Thus, the patterns obtained can be explained by both the anthropogenic impact on ecosystems associated with tree cultivation activities in botanical gardens and a complex of natural factors (climatic, edaphic, phytocenotic) operating at the investigated sites.
Kalinkina et al. (Sun,) studied this question.