Chin J Plant Ecol ›› 2008, Vol. 32 ›› Issue (1): 133-142.DOI: 10.3773/j.issn.1005-264x.2008.01.015

• Research Articles • Previous Articles     Next Articles

SEED DISPERSAL AND SPATIAL-TEMPORAL VARIATION OF SEED PREDATION OF MUSA ACUMINATA IN XISHUANGBANNA, SOUTHWEST CHINA

MENG Ling-Zeng, GAO Xiu-Xia, CHEN Jin*()   

  1. Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
  • Received:2006-11-03 Accepted:2007-10-09 Online:2008-11-03 Published:2008-01-30
  • Contact: CHEN Jin

Abstract:

Aims Seed dispersal and seed predation are important on mechanisms of forest maintenance and degeneration. Understanding them can enable effective conservation measures, especially in Xishuangbanna tropical rainforest in China which is suffering severe pressures.
Methods Musa acuminata is a large herbaceous plant in Xishuangbanna, Yunnan Province. We investigated seed dispersal and spatial-temporal variation of seed predation in three habitats (wild banana communities, virgin rainforest and open habitat) in three different sites of Xishuangbanna (XTBG, Xinshan and Bubeng). We used two treatments excluding ants and rodents and surveyed community structure of ants and rodents to explore the relationship between abundance of predators and intensity of seed predation.
Important findings Bats were the most important, effective seed disperser, and birds also played an important role in seed dispersal, with approximately 75% of the mature fruits of M. acuminata dispersed at night and about 25% during daytime. After primary dispersal, seeds of M. acuminata were mainly removed by small rodents and ants. This seed predation was significantly influenced by season, site and habitat. Seed predation was significantly stronger in rainy than dry seasons (p<0.001). Seed predation in M. acuminata communities was the highest among the three habitats (p<0.001), and seed predation in Bubeng Nature Reserve, which had the least disturbance, was significantly lower than the other two sites (which were not significantly different at p>0.05). Seed removal was generally consistent with the abundance of rodents and ants in different seasons, habitats and sites. The interaction between sites and habitats and the interaction among seasons, sites and habitats had significant effects on seed predation. Compared to nearby forest and open habitats, Musa communities had the most abundant rodents and the highest seed predation and the lowest proportion of secondary seed dispersal by ants. In contrast, seed predation by rodents in forest and open habitat was relatively weak and a large proportion of post dispersal seed was removed by ants. Therefore, primary seed dispersal mostly by bats and birds is essential for M. acuminata seeds to escape seed predation.

Key words: Musa acuminata, spatial-temporal variation, seed dispersal, seed removal, Xishuangbanna