Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 88. (Budapest 1996)

Madari, B., Kiss, I. ; Korsós, Z.: Community-structure parameters of millipedes (Diplopoda) in five different habitats

MATERIAL AND METHODS Description of the sample areas. Sampling has been carried out in five selected areas around Gödöllő. Sampling areas were determined in a way that potentially all characteristic associations be examined in the region. The first area is situated near Valkói Road. The dominant species of the vegetation in this area is robur (Quercus robur), the surface is plain, the soil is dry since the canopy of trees holds the precipitation up from the ground and as a result the soil can not soak wetness further down than 10 cm. The dominant species in the second area is Scotch fir (Pinus sylvestris). Its topography is also plain and the soil also tends to dry. The third sampling plot is an island-like area surrounded by arable land. The place is mainly covered by trees but thorn-bush (Crataegus monogyna), maple (Acer tataricum) and wild rose (Rosa sp.) can also be found. The area is on a higher elevation than its surroundings, its soil also tends to be dry. The fourth area is inside the borders of the Gödöllő Hills Landscape Protection Area. It is a clear cut where acacia (Robinia pseudoacacia) was the previous dominant species in the vegetation. Now there is a 40-50 cm high Austrian oak (Quercus cerris) planting. This is a slightly sloping area and the soil is able to soak noticable amount of water. The fifth area is also situated in the Protected Area, acacia (Robinia pseudoacacia) predominates the vegetation. Bedstraw (Galium molluga) creates rich underwood. The area is slightly sloping and its water keeping ability is similar to the previous one. Method of sampling. Altogether 19 pitfall traps were used in the five sampling areas. The number of traps per sampling area was proportional to the size of the plots (4, 2, 3, 5, 5). The traps were positioned in a line, approximately 20 m away from each other, and were filled with a 2:1 mixture of water and ethylene-glycol. Ethylene-glycol kills the arthropods rapidly, it also preserves them for a shorter period. Repellent and attracting effect for the animals is not known (see e. g. HOFFMAN 1990). The traps were emptied in every three week. Since pitfall traps are only effective in collecting animals moving and searching for food on the soil surface or in the upper layer, we also examined samples from the litter material and from the upper layer of the soil with Tullgren-funnel in each study area. Data obtained with these methods were supplemented by singling for species by hand. Sampling was carried out over two years and the traps were emptied 19 times during that period. Since millipedes, like many other soil dwelling arthropod species, hibernate in the deeper horizons of soils, and do not or only move a very little, we began sampling early in the spring and the traps were out till late autumn each year. Dates of pitfall trap c m p t y i n g : 1: 25 June 1992, 2: 10 April 1992, 3: 7 May 1992, 4: 3 June 1992, 5: 22 June 1992, 6: 15 July 1992, 7: 1 August 1992, 8: 29 October 1992, 9: 19 November 1992, 10: 30 April 1993, 11: 17 May 1993, 12: 15 June 1993, 13: 2 July 1993, 14: 21 July 1993, 15: 11 August 1993, 16: 8 September 1993, 17: 29 September 1993, 18: 20 October 1993, 19: 10 November 1993. Preparation of the material. Collected millipedes are stored in isopropylealcohol with 5 volume per cent glycerine (see e. g. BLOWER 1985), and deposited in the soil zoological collection of the Department of Zoology and Ecology, Gödöllő University of Agricultural Sciences. The material was identified under a stereo microscope with the help of the literature by BLOWER (1985), HOFFMAN (1990), and LOKSA (1984). In order to obtain correct result in the analysis of relative abundance, the number of millipedes in each sampling area was devided by the number of traps on each area, and these data have been used in the estimation.