关键词: 科尔沁沙地, 围封草地, 种子库

Abstract: The seed bank of sandy grassland after 7 years enclosure (no grazing) was investigated. The results showed that ①the number of plant species was 25, and that of annuals and biennals was 19 in the seed bank; ②The density of seed bank was 3 314 grains·m^-2, and 95.3% of that was seeds of Artemisia scoparia, Setaria viridis and Aristida adscensinis and other annuals, whilst 4. 7% of that was those of perennials; ③If divided into monotyledoneous and dicotyledonueous, the number of seeds of former accounted for 14% of that of total seeds while that of later constituted 86%,and that of bean family species comprised 2. 4%; ④There exists a significant correspondence between the number of seed bank and the frequency of associated vegetation;⑤The fenced grassland vegetation will be in the stage of mixture of Artemisia scoparia and forbs; ⑥Fenced grasslands provided their surrounding disturbed grassland a seed island. This can reduce the restoration processes of these disturbed habitats effectively. Therefore, the relevant researches on the management and utilization of fenced grasslands should be paid more attention to.

Key words: Horqin Sandy Land, fenced grassland, seed bank