The biodiversity and community structure of soil ciliates of Talish forests in south-eastern Azerbaijan

Abstract

New information on the fauna of the soil ciliates of south-eastern Azerbaijan is presented in this article. As a result of surveys conducted in 2017–2019, 65 species of soil ciliates assigned to 33 families were recorded. The highest diversity of pedobiont ciliates was observed in Masalli and Lankaran forest soils. On the other hand, the lowest species diversity was recorded in the Astara region. The highest species diversity was found for the family Colpodidae, of which 7 species were found. Four of them belong to the pedobiont genus Colpoda. Almost all representatives of this genus are typically soil species and euribionts with wide ecological plasticity. In addition, two species that are the representatives of the genus Tillina were found in soil, but they can be occasionally found in freshwater bodies. It should be noted that the special climatic conditions of south-eastern Azerbaijan impact on the distribution regularity of ciliates in the mountain-forest soils. The accumulation of ciliates in forest soils in spring was observed in the upper horizon of the 5 cm soil litter layer in summer. Due to the decrease in humidity in upper layers, pedobiont ciliate migrates to deeper layers (10–15 cm), and in autumn with the increase in precipitation and humidity in the upper soil horizons, the mass of soil ciliates is again localized in the forest litter and in the upper soil layer. It is also worth noting another specific complex of ciliates in the forest soils of south-eastern Azerbaijan. In early spring and autumn, with the maximum moisture content in the forest soil, we often observed ciliates, which usually dwell in fresh waters. Among them are representatives of such genera as Zosterodasys, Nassula, Aspidisca, Blepharisma, Frontonia, Urotricha etc. The species diversity and community similarity index of soil ciliates in Talish forests of Lankaran natural area were also calculated. The study attempts to compare the difference in ciliates community among five different regions of south-eastern Azerbaijan. The analysis showed that there are 3 clusters of the similarity of species diversity of ciliate communities. The similarity between the ciliate fauna of the high mountainous regions and fauna of the plain regions was 52.15–69.00 %.