Abstract

In 2004-2005, a lysimetric experiment was designed to determine whether and how plant diversity and earthworms could influence diversity and densities of collembolan communities. We compared two types of crops: monoculture of Festuca rubra L. and a polyculture, the mixture of grasses commonly used in agriculture. In addition to two plant communities of different diversity, we used in our experiments an engineering species of earthworm – Aporrectodea caliginosa. The experiment was initiated in May 2004, when the lysimeters were sown with F. rubra or with a mixture of grasses. The following year, in May 2005, we introduced 6 individuals of A. caliginosa to half of the lysimeters. Soil samples were taken at the depths of 0-5 cm, 5-10 cm, 10-15 cm and 15-20 cm, before introducing earthworms and after 60, 120 and 180 days from introducing earthworms. We found that soil layer, biodiversity of grass culture and the period of the season had an important effect on densities of collembolan communities independently of earthworms presence. We found 18 species of springtails and the number of species decreased with soil layer. The most abundant were Proisotomodes bipunctatus and Isotomodes productus.