The Ecological Structure Of Oribatid Mites Population (???osnovnoy??? Quarry, Donetsk Region)
A. D. Zhtirts
In the successional recovery processes of quarry-spoiled systems soil-living oribatide mites, who are one of the pioneer groups inhabiting anthropogenically transformed areas, play a significant role. The aim of our study was to research composition and characteristics of oribatide mites ecological community structure of the ‘Osnovnoy’ quarry (PJSC ‘HeidelbergCement Ukraine’) in Amvrosievsky district of Donetsk region. The material was collected in 2012. In total, 37 standard soil samples of 250 cm3 were collected, from which 1086 adult specimen, who belong to 61 species, were extracted in April. The collection of soil samples and forcing of oribatides in thermoelectors was conducted by the conventional method of E. M. Bulanov?-Zahvatkin?. To analyze the communities domination structure the gradations of dominance by the means of G. Engelmann scale was used. The analysis of the oribatides morpho-ecological types distribution was held in accordance to the work of D. A. Krivolutsky. To assess the ecological diversity of oribatides communities the indices of Shannon, Pielou, Simpson and Margalef were used. On the territory of the «Osnovnoy» quarry, a specific complex with a unique oribatid species composition was detected (two new species were found for the fauna of Ukraine noted earlier for the steppes of Mongolia: Ghilarovus khentiicus Bayartogtokh, Smelyansky, 2007 and Hemileius humeralis Perez-Inigo, 1990). During the analysis of the oribatide communities ecological structure low rates of average population density (7280-11410 ind./m2) were observed with high species wealth (61 species found). The maximum figure made up in spring, the minimum – in summer. The ecological diversity indexes are quite high, thus the maximum for Shannon index in spring is 2.89, which is comparable to that of the conserved areas. The quarry dominant species are Multioppia glabra, Protoribates capucinus, Tectocepheus velatus, Scheloribates laevigatus, and Zygoribatula frisiae. A distinctive feature of the oribatid mites’ population structure at the technogenic landscape is the presence of a large number of rare species, especially in spring, which is comparable to that in the undisturbed grassland ecosystems. In the oribatid life forms spectrum the presence of all morpho-ecological types is noted, which is a key feature for intact landscapes. In summer and autumn period a clear predominance of secondary specialized forms, typical for anthropogenic landscapes, was observed; in spring the structure is more aligned, and the residents of small soil wells make up a significant part of the population.