Chin J Plant Ecol ›› 2009, Vol. 33 ›› Issue (1): 161-170.DOI: 10.3773/j.issn.1005-264x.2009.01.018

• Research Articles • Previous Articles     Next Articles

EFFECTS OF BIOLOGICAL CRUSTS ON THE GERMINATION OF FIVE DESERT VASCULAR PLANTS WITH DIFFERENT SEED MORPHOLOGIES

NIE Hua-Li1,2(), ZHANG Yuan-Ming1,*(), WU Nan1,2, ZHANG Jing1,2, ZHANG Bing-Chang1,2   

  1. 1Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
    2Graduate School, Chinese Academy of Sciences, Beijing 100049, China
  • Received:2007-10-09 Accepted:2008-01-08 Online:2007-10-09 Published:2009-01-30
  • Contact: ZHANG Yuan-Ming
  • About author:First author contact:

    E-mail of the first author: niehuali@163.com

Abstract:

Aims As a universal, common feature in arid and semi-arid regions, biological crusts can affect soil surface properties which may relate to seed dispersal, germination and establishment of vascular plants. Numerous studies have addressed aspects of the influence of crusts on vascular plants; however, the interaction between crusts and vascular plants is controversial. Our objective was to examine effects of biological crusts on seed germination of desert vascular plants with different seed morphologies in Gurbantunggut Desert, China.
Methods Gurbantunggut Desert, the largest fixed and semi-fixed desert in China, has well-developed biological crusts. We conducted a series of shadow experiments to examine the effects of biological crusts on seed germination of Haloxylon persicum, Ephedra distachya, Ceratocarpus arenaarius, Malcolmia africana and Lappula semiglabra.
Important findings The effects of biological crusts on germination were variable under both moist and dry conditions. The presence of crusts significantly reduced germination of Ceratocarpus arenaarius and Malcolmia africana compared with surfaces from which the crusts had been removed, but there was no significant effect on germination of the other species under dry conditions. Under moist conditions, seed germination of Haloxylon persicum, Ceratocarpus arenaarius and Lappula semiglabra was significantly lower on crust than on the surface devoided of crust, and there was no significant effect for Ephedra distachya and Malcolmia africana. In general, biological crusts affected the germination of some vascular plants, but whether the effect was negative or positive depended on water condition and biological characteristics of the seeds.

Key words: biological crusts, seed germination, seed morphology, desert vascular plants, Gurbantonggut Desert