Influence of Landscape and Climate on the Abundance of Earthworms in Forest Ecosystems of the Southeast of Western Siberia

The taiga and forest-steppe ecosystems of Western Siberia are subject to significant climatic and anthropogenic transformations. Understanding the relationship between the abundance of earthworms, which play an important role in forest communities, and environmental conditions can be used in monitoring the state of ecosystems. The aim of the work was to identify the relationship between the abundance of earthworms in communities of the forest-steppe and taiga zones in the southeast of Western Siberia with landscape features, climatic parameters of the environment, and the timing of material collection during the warm season. The analysis included data on earthworm abundance from 62 habitats. The modeling was carried out by factor analysis of mixed data (FAMD). To identify the relationship with the abundance of earthworms, quantitative data on soil types and vegetation, physical and chemical soil characteristics, climatic parameters and categorical data on orographic and hydrothermal zoning, geobotanical zoning on soil types and vegetation, and collection dates were considered. In all cases, the observed dispersion is better explained by the hydrothermal zoning of the territory, climatic and soil conditions, and the obtained patterns are more indicative of the number of morpho-ecological groups, rather than individual species of earthworms. The assumption is confirmed that the dependence on parameters affecting soil moisture is observed in the anecic group of worms, while in other cases there is no strong connection. It follows that in the south of the taiga zone and in the forest-steppe in the southeast of Western Siberia, the observed abundance in communities will depend to a lesser extent on months of collecting material than is generally accepted for temperate zone ecosystems.