Soil Organisms (Dec 2015)
Depth distribution and inter-annual fluctuations in density and diversity of Collembola in an Iranian Hyrcanian forest
Abstract
The Hyrcanian forests as an ancient and one of the most unique temperate deciduous broadleaved forests in the world are located partly in the north of Iran near the Caspian Sea. Collembola as a major group of soil animals have never been studied in the Hyrcanian forests. We investigated the Collembola fauna of the Semeskandeh forest as a part of the Hyrcanian forests in northern Iran (Mazandaran province) in different soil horizons as well as in different seasons to gain insight into the diversity and dynamics of the Collembola community. Samples from leaf litter (OL,F,H horizons), 0–3 and 3–6 cm of the mineral soil (Ah horizon) were assessed in two-month intervals during one year (2012–2013). A total of 20 species belonging to 16 genera and 9 families were identified. Heteromurus major (Moniez, 1889) was most abundant and the species Lipothrix lubbocki (Tullberg, 1872), Heteraphorura japonica (Yosii, 1967), Sminthurus cf. ghilarovi Stebaeva, 1966, Paralipothrix cf. natalicius (Ellis, 1974), Dicyrtomacf. ghilarovi Bretfeld, 1996 and two Sphaeridia spp. were recorded for the first time for the Iranian Collembola fauna. Abundance of Collembola was highest in leaf litter in winter (January) and lowest in 3–6 cm soil depth in summer (July). Species diversity was highest in winter in leaf litter and low in summer particularly deeper in soil. Overall, the depth distribution of Collembola resembled that of temperate forests, whereby seasonal dynamics differed with highest densities in winter, indicating that reduced moisture in summer functions as a major determinant factor. The results provide for the first time information on the diversity and dynamics of an important decomposer animal taxon in an endangered forest system of southwest Asia.
