立地条件の異なるススキ型二次草地における埋土種子相と地上植生の比較

Abstract

This study aimed at comparing the seed bank compositions of Miscanthus sinensis grassland established on two different topographical conditions to make clear the appearance of grassland species from the seed source in the soil. We conducted germination tests for soil samples taken from the managed grassland on the flat floor of the Tsukuba-Inashiki Upland and the steep slope adjacent to the 'Yatsu' paddy fields. The buried seed composition was greatly different between them. The grassland on the steep slopes contained more species and seed grains per soil sample than those on the upland. Although more than 20 grassland species appeared in the above ground vegetation, only a few sprouted from the soil seed bank of the grassland along the 'Yatsu' paddy fields, while from the grassland on the flat floor eight grassland species appeared. The results of this study suggests that the soil seed bank of the Miscanthus sinensis grassland on both topographical conditions contribute little as a source of native grassland species.