Abstract:
In this paper, the soil seed bank in the water-level-fluctuating zone of Aha Lake reservoir of plateau seasonal wetland was selected as the research object to investigate the germination ability of 4 typical types of unflooded soil seed banks including arbor forest, shrub land, grass land and abandoned farmland in Aha Lake reservoir area, and 9 treatments were set for 0, 2, 5, 10, 20, 30, 40, 60 and 90 days of waterlogging respectively. The results of this study were expected to provide a basis for the construction of artificial seed banks for ecological restoration in water-level-fluctuating zones. The results showed the density of the 4 soil seed banks ranged from 1 651 to 3 730 seeds·m
-2, which showed as grass field > abandoned farmland>shrub land>arbor land. The number of soil seed banks was concentrated in the 0-5 cm soil layer, accounting for 70%-75% of the total number. In addition, a total of 71 species belonging to 31 families germinated from 4 types of unflooded soil seed banks, and the most germinated species belonged to Compositae, followed by Gramineae. After 2, 5, 10, 20, 30, 40, 60 and 90 days of water flooding in 4 types of unflooded soil seed banks, the number of germination accounted for 99.50%, 97.53%, 93.33%, 86.66%, 78.02%, 66.42%, 54.57%, 42.22% of the total germination, respectively, while the number of germination species accounted for 100%, 98.59%, 95.77%, 88.72%, 77.46%, 67.61%, 57.75% and 47.89% of the total germination number respectively, which implied the short-term flooding had little effect on the soil seed bank, while the long-term flooding could seriously inhibit the germination of seeds. After 90 d of water flooding, the species with an excellent budding potential were Galinsoga parviflora Cav., Rumex acetosa L., Oenanthe javanica(Bl.) Dc., Bidens pilosa L. and Conyza canadensis(L.) Cronq., which indicated that the seeds of these plants had strong waterlogging tolerance and could be used in artificial vegetation restoration measures in the water-level-fluctuating zone of wetlands.