Secondary Successional Stages of Soil Nematodes in Cambisols of South Bohemia

Abstract

The secondary succession of soil nematode communities from cultivated field to oak subclimax forest on cambisols was studied in South Bohemia in the course of 1986-1987. The successional stages studied were a cultivated field, fallow, meadow and oak forest. A total of 150 species of nematodes was found, 71 in the field, 69 in the fallow, 109 in the meadow, and 104 in the forest. The most diverse nematode community was found in the meadow, diversity and abundance of nematodes were positively and significantly correlated in the successional sequence studied. The genera Rhabditis, Filenchus, Plectus, Acrobeloides, Aporcelaimellus, Panagrolaimus, Eudorylaimus, Mesodorylaimus, Aphelenchoides, Ditylenchus, Bursilla, Cephalobus and Eumonhystera were common in all successional stages. Specialized genera (and species) were found in the meadow and the forest stands. The highest abundance of nematodes (1.52 x 10 6 ind. m- 2 ) was found in the forest, the lowest one (0.54 x 10 6 ind.m- 2 ) was in the field. A similar trend was found for nematode biomass. The seasonal changes of abundance were marked by two peaks in the field, the forest, and in the one-year-old fallow, while in the two-year-old fallow the abundance had one peak, and in the meadow no distinct maxima or minima of abundance were found. Bacteriophagous and mycophagous nematodes dominated in early successional stages, the importance of omniphagous and predaceous nematodes increased as the succession progressed. The highest abundance of phytophagous nematodes was found in the meadow, while in the forest they were practically absent.