Theoretical Study of Spatio-Temporal Dynamics of Synchronized Flowering and Reproduction of Trees in Forests

森林树木同步开花与繁殖的时空动态理论研究

基本信息

批准号：
12640616
负责人：
IWASA Yoh
金额：
$ 2.3万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

Trees in mature forests often show intermittent reproduction. Intensive flowering and seed production occur only once in several years, often synchronized over a long distance. We study a coupled map model for the dynamics of energy reserve of individuals, and show that trees become synchronized in reproduction when their fruit production is limited by the availability of outcross pollen. Without pollen limitation, the trees show independent chaotic fluctuation. With global pollen coupling, trees show various degree of reproductive synchronization. Lyapunov exponents are calculated analytic ally for perfectly synchronized forests, demonstrating that synchronized reproduction of trees can occur only if trees flower at low (but positive) levels in a significant fraction of years, resulting in small fruit sets due to the shortage of outcross pollen. We then study a coupled map lattice with local pollen exchange. Dynamic spatial covariance shows that a strong synchronization over the whole forest can develop from rather short range pollen exchange. We then examined the synchronization caused by common environmental fluctuation either in the annual productivity or the reproductive threshold level. Without pollen coupling, positive correlation between individuals are difficult to emerge even under environmental fluctuation correlated between individuals. Positive correlation can be maintained at high level only in the presence of both pollen coupling and correlated environmental fluctuation. We also discuss the reproductive synchronization between different species who share common pollinators, which is applicable to the synchronization in the tropical rain forest in Southeast-Asia. The first paper was printed in JTB, the second in now (in press) in Ecology, and another was submitted to J Ecology.

成熟森林中的树木经常显示间歇性繁殖。密集的开花和种子产量仅发生几年，通常在很长的距离内同步。我们研究了个体能量储备动力学的耦合地图模型，并表明当树木产量受到欧面花粉的可用性限制时，树木在繁殖中变得同步。没有花粉限制，树木显示出独立的混沌波动。随着全球花粉耦合，树木显示出不同程度的生殖同步。 lyapunov指数是针对完美同步森林的分析盟友计算的，表明只有在大量年内树木在低（但正）的水平上以低（但正）水平开花的同步树木的同步繁殖才能发生，从而导致小水果套装，因此由于露出粉粉的短缺而导致果实集。然后，我们研究了与局部花粉交换的耦合地图晶格。动态空间协方差表明，整个森林的强同步可以从相当短的花粉交换中发展出来。然后，我们检查了在年度生产力或生殖阈值水平中由常见环境波动引起的同步。没有花粉耦合，即使在个人之间相关的环境波动下，个体之间的正相关也很难出现。仅在花粉耦合和相关的环境波动的情况下，正相关才能保持高水平。我们还讨论了共有共同传粉媒介的不同物种之间的生殖同步，这适用于东南 - 亚洲热带雨林中的同步。第一篇论文是在JTB中印刷的，第二篇论文是在生态学中（印刷中）的第二篇论文，另一篇是j生态学。