Lyubechanskii I.I., Azarkina G.N., Dudko R.Yu. 2017. [Soil-dwelling predatory arthropod community (Insecta: Carabidae; Arachnida: Araneae; Opiliones) in the valley ecosystem of the Upper Ob river at the beginning and end of the season activity period] // Euroasian Entomological Journal. Vol.16. No.2: 141–150 [in Russian, with English summary].
Institute of Systematics and Ecology of Animals, Russian Academy of Sciences, Siberian Branch, Frunze Str. 11, Novosibirsk 630091 Russia.
ABSTRACT. Assemblages of predaceous soil-dwelling arthropods (carabid beetles, spiders and harvestmen) in the valley of the Ob river near Novosibirsk (West Siberia, Russia), including forest and bog sites, were studied. Recording was conducted in April, June and September of the extremely long growing period of 2016. In four sites differing in their geomorphological position and humidity, 33 species of ground beetles from 17 genera, 33 species of spiders from 14 families and 1 species of harvestmen (last group only in the autumn period) were found. The same localities turn out to be high (birch forest, floodland) or low (pine and boggy forests) species richness both in carabids and spiders. The highest values of average dynamic density in studied groups were localized in different sites, namely in the floodland for spiders and in the birch forest for ground beetles. The dynamic density of carabids in all sites except the floodland was higher than that of spiders. Carabid and spider communities are grouped into two clusters by similarity of their populations, moist (floodland, boggy forest) and dry (birch and pine forests). From spring to autumn, species richness and density generally decreased both in carabids and spiders. The shift of the warm period to earlier dates causes the beetles and spiders to start their seasonal activity earlier; however, spiders stay active longer in autumn, which may be connected with physiological adaptations to the low temperatures as well as the drop-out of their carabid competitors in hibernation at that time.
KEY WORDS: carabid beetles, spiders, spatial distribution, microclimate, range, nature protected areas, Opiliones.