Biodiv Sci ›› 2001, Vol. 09 ›› Issue (1): 25-37.DOI: 10.17520/biods.2001004

• 论文 • Previous Articles     Next Articles

Relationship between animals and plant regeneration by seed Ⅱ. Seed predation, dispersal and burial by animals and relationship between animals and seedling establishment

LI Hong-Jun, ZHANG Zhi-Bin   

  1. Institute of Zoology,Chinese Academy of Sciences,Beijing 100080
  • Received:2000-07-20 Revised:2001-02-20 Online:2001-02-20 Published:2001-02-20
  • Contact: ZHANG Zhi-Bin

Abstract: The propagules of plants are exposed to high risk of attack by natural predators, such as insects, vertebrates and fungi. Seed mortality due to predation by animals may affect plant fitness, population dynamics, community structure and maintenance of species diversity. The time and intensity of seed predation can be a major selective force in the evolution of life history traits in plants, such as germination rates and production of a soil seed bank. Seed size and the type and patchiness of habitat affect seed predation by animals. Predator satiation is a highly coevolved behavior interaction of plant with seed predator, and has been proposed as a selective factor limiting the destructive abilities of animals and promoting the survival of dispersed seeds. Several hypotheses have been proposed to explain the spatial relationship between plant regeneration and seed dispersal. Seed dispersal can be regarded as a key process in the survival and distribution of plant species. Seeds are dispersed through a variety of ways. Seed dispersal affects the fitness of parent and offspring plants through its effects on seed density, the distance seeds are moved from the parent tree, and the habitat where seeds arrive. Difference in dispersal may influence early seed and seedling survival by affecting incidence of predation or attack by pathogens, the habitat into which seeds are dispersed, and the types of plants with which the developing plant will compete. Seed distribution generally exhibits a negative exponential function, most seeds are not disperse very far from the parent plant. Predation risk, habitat type and vegetation cover are factors which affect animal dispersal of seeds. The fruiting season and fruit loss process of plants reflects adaptation to dispersal opportunities. A large number of animals hoard plant seeds. This behavior not only adjusts spatio temporal distribution of food and enhances animal survival in times of food shortage, but also promotes plant dispersal. So, there is coevolutionary relationship between plant and animal which cache or hoard seeds. Seed dispersal by animals is one of the most important of mutualistic systems. Many factors affect the survival and establishment of seedling, such as microhabitat, humidity, slope, gradient, cover of the cache. Frugivorous animals usually consume the pulp and regurgitate or defecate the seeds intact. Seed treatment within the guts of seed dispersers is contributive to seed emergence.