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Density of microarthropods, Collembola and Acarina were studied in 2000 in soil and litter of 7-years old shelterbelt and in nearby field sown by winter wheat in Turew (Wielkopolska Region, West Poland). Samples were taken in the shelterbelt centre and in the field at a distance of 0.5 m, 10 m and 50 m from the tree line. Collembola were analysed in soil and in litter samples placed in containers and located in different sites, Acarina only in soil samples. Density of Collembola in soil was found to be higher in the shelterbelt than in the adjacent field (P =0.003). Similar relationship was not, however, noted for insects in litter, density in open field was higher than in the shelterbelt. Density of Acarina in soil decreased gradually with the distance from the shelterbelt (P =0.007). Twenty three species of springtails were found; the highest species richness (12) was noted in shelterbelts, but also in the litter in the open field. The dominant species common for soil and litter were Isotoma notabilis in the shelterbelt while Isotomina thermophila and Isotoma viridis in the field. With the increasing distance from shelterbelt Proisotoma minuta increased its contribution to the soil community, Entomobrya multifasciata was the dominant only in litter. In the field soil, 50 m from woods, the highest share of young individuals was noted. The highest species richness of Oribatida was found in the field margin (18). The Tectocepheus velatus was the dominant species both in the shelterbelt and the field, accounted for 30–70% of the total number of individuals.
The communities of soil mesofauna were studied in the year 2004 along three transects crossed shelterbelts of different age (6, 11 and 170 years old) and adjacent wheat fields at a distance of 0.5, 15 and 50 m. Studies were carried out in the Gen. D. Chłapowski Landscape Park near Turew, Western Poland (16°45’E, 52°01’W). The age of shelterbelts vegetation affected soil mesofauna of adjacent fields in a diverse way. The mean density of mites amounts 7.4 × 10³ ind. m⁻² and 2.6 × 10³ ind. m⁻² respectively for the shelterbelts and fields. Densities of Acarina communities were affected not only by the presence of a shelterbelt (P = 0.000) but also its age (P = 0.02) and the distance from it (P = 0.000), and these effects were similar in spring and autumn (P = 0.08). The mean density of springtail noted in shelterbelts of different age was 2.0 × 10³ ind. m⁻² and in the field sites 2.2 × 10³ ind. m⁻². Although the effect of the shelterbelts’ age on the density of Collembola was not found (P = 0.3), the densities were different in shelterbelts and in adjacent fields (P = 0.006) but statistical significance was found only between spring and autumn (P = 0.000). The distance from the shelterbelt influenced (though less intensely) the density of Collembola on adjacent field (P = 0.01). Eighteen species of Collembola were found in studied shelterbelts and fields. Isotoma notabilis Schäff. usually dominated in shelterbelts. Its contribution to abundance of communities varied depending on the age of shelterbelts (in 6 years old shelterbelt it constituted as many as 71% of the whole community). In 11 years old shelterbelt Schoetella ununguiculata (Tullb.), was more common than Isotoma notabilis Schäff. and in the 170 years old shelterbelt the dominant species was Onychiurus armatus (Tullb.). Friesea mirabilis (Tullb.), Proisotoma minuta (Tullb.), Isotoma notabilis or Onychiurus armatus dominated in adjacent fields though their contribution was depended on shelterbelt’s age and on the distance from it.
An experiment was conducted in plastic pots filled with loamy sand and inserted into the soil. Half of the pots were sown with one species, orchard grass, and half with a mixture of six grass species. Every year at the end of May, half of the pots in each variant was enriched with 300 g DM of earthworm casts per pot. To estimate the abundance of Enchytraeidae, Acarina and Collembola, soil samples were taken three times per season. The abundance of enchytraeids was significantly higher in the orchard grass monoculture and in pots enriched with earthworm casts, especially at high population densities. No unequivocal effect of vegetation and earthworm casts on the Acarina and Collembola density was observed.
Natural forest fires are considered as a part of natural ecosystem processes. Short-term effects of prescribed fire on densities and taxonomic diversity of soil Acari were studied in fresh pine mixed forest (“Biala” forest ) in the Mazovia region, Central-Eastern Poland. Three plots (size 1 m²) of similar soil type and vegetation were selected for prescribed burning. Soil samples of an area of 10 cm² and the depth of 5 cm were collected in June 2005 – one day after the burning, 60 days after the burning and 90 days after the burning. Samples were collected from within the border of the burned plots, from the border itself, as well as from the surroundings. Due to the burning, the density of Acari communities decreased from 11.5 × 10³ ind. m⁻² recorded in the surroundings to 3.2 × 10³ ind. m⁻² recorded in the burned plots. Values recorded within the burned plots after the fire differed significantly from those recorded on the border (P = 0.05) and in the surroundings (P = 0.0001). After 60 days, an increase in Acari abundance was observed in the burned plots (P = 0.02), becoming similar to that noted for the border of the plot and for the surroundings. After 90 days, there were no significant differences between the burned parts of the plots, their borders and the surroundings; however, generally decreased densities were observed, possibly due to the seasonal reason. The observed changes suggest the restoration of Acari community after disturbance.
Data on the density and the body mass of a single community of soil fauna were collected and metabolic rates were calculated from the literature data to test some predictions of the metabolic theory of ecology on the local scale. Part of the results are in accordance with the theory: power functions were found between the metabolic rate and the body mass, and between the density and the body mass. These two relationships have opposite exponents inducing that total population energy use is independent of the body mass. However, the exponents of the relationships were significantly different from the predicted values of |3/4|. The metabolic rate - body mass relationships yielded an exponent >0.8, while the density - body mass relationships yielded an exponent <-0.85. Our results indicate that the metabolic theory of ecology does not hold at the local level. Few studies have been carried out on the local scale and further analysis is required to validate this controversial but promising theory.
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