竞争与正相互作用对物种间特性差异的反应模式  

Relationship of interspecific facilitation and competition to the attributes of the interacting species

作　　者：陈书燕[1] 徐瑾[1] 王刚[1] 张甲林[1] 肖洒[1] 

机构地区：[1]兰州大学生命科学学院干旱与草地生态教育部重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2009年第2期48-54,共7页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金项目(30770360与20776112);教育部博士点新教师基金项目(20070730047;20070730051)

摘　　要：构建了一个空间明晰的网格模型,旨在探讨物种间竞争和胁迫忍耐能力的权衡对种间相互作用类型与结果的影响及其对于环境胁迫状况的响应.结果表明:忍耐种对竞争种的正作用不但促进了竞争种数量的增加,并且极大扩展了竞争种的空间分布范围,最终导致其实现生态位大于基础生态位;然而忍耐种对竞争种的这种促进作用却使竞争种对忍耐种的竞争排除作用极大地增强,使忍耐种的数量与分布范围均出现了较大的下降与缩减.因此两物种间的相互作用类型为"+,-"型,不同于传统的正相互作用概念中的"+,+"及"+,0"类型,为进一步探讨沿环境梯度的正相互作用和竞争的关系以及该过程对于种群动态及群落构建的影响提供了一条崭新的途径.A spatially explicit model was introduced to evaluates how the trade-offs between the strategies of the interacting species, a competitor and a stress-tolerant affect the outcome of their interaction along environmental severity gradients. The results show that the facilitation that the stress-tolerant imposed on the competitor increased the number of the latter and expanded the realized niche of the latter by promoting its distribution into harsh environments. Due to the differences between the competitive ability and stress tolerance of both species and despite their similar ability to ameliorate environmental harshness, the actual positive effects that the two species received from each other were totally different. The effect of facilitation to ameliorate the abiotic stress was so finite that the stress tolerance would take the place of the competitor and hold dominance when the stress tolerance of competitor was poor. Our model provides a new framework for investigating the interplay of facilitative and competitive interactions and their impacts on processes such as population dynamics and community organization along environmental gradients.

关 键 词：正相互作用 竞争 网格模型 环境胁迫梯度 胁迫忍耐 生态位 

分 类 号：Q141[生物学—生态学]