Chin J Plant Ecol ›› 2011, Vol. 35 ›› Issue (3): 247-255.DOI: 10.3724/SP.J.1258.2011.00247

• Research Articles • Previous Articles     Next Articles

Comparison of the established vegetation and soil seed bank of tidal flat versus tributary habitats of China’s Danjiangkou Reservoir: the potential of hydrochory

XIAO Chan1,2, LIU Wen-Zhi1, LIU Gui-Hua1,*()   

  1. 1Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China
    2Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2010-10-11 Accepted:2010-12-01 Online:2011-10-11 Published:2011-03-02
  • Contact: LIU Gui-Hua

Abstract:

Aims Our objectives were to compare the established vegetation and soil seed bank of tidal flat and tributary habitats of the Danjiangkou Reservoir of China’s Han River and to identify the contribution of hydrochory (dispersal of seeds by water) from the tributaries to the reservoir tidal flats.
Methods We sampled the vegetation and soil seed banks of four tributaries and the reservoir tidal flats of their estuaries. Using data from 91 sample plots, we compared the species composition of the established vegetation and soil seed banks of the tributaries and their tidal flats using Sørensen’s coefficient of similarity, detrended correspondence analysis (DCA) and two way indicator species analysis (TWINSPAN).
Important findings Species richness of the established vegetation and seed bank along the tributaries was considerably higher than in the reservoir tidal flats, but the density of seedlings germinated from the soil seed bank was not significantly different between the two habitats. TWINSPAN and DCA showed a separation of sites from the tributary and tidal flat zones. In the DCA ordination diagram, however, most species were grouped between the tributaries and tidal flats, indicating a close relationship of species composition between the two habitats. Sørensen’s coefficient of similarity also revealed a high similarity of the established vegetation and seed bank between the tributaries and the tidal flats. Seeds were germinated from all three layers of the top soil (0-15 cm) in the Han reservoir tidal flats, while only one species, Cynodon dactylon, was found in the top soil of 0-5 cm in the Dan Reservoir tidal flats. Our results indicate a potential contribution of hydrochory from the tributaries to the vegetation of the reservoir tidal flats.

Key words: dam, hydrochory, vegetation restoration, water-level-fluctuation zone