风力驱动的榆树疏林种子扩散模拟

The simulation in wind-driven seed dispersal of Ulmus pumila in sparse woodland steppe

种子扩散是榆树疏林天然更新研究的重要内容,榆树种子扩散主要为风力驱动。为探究风力对种子扩散的影响,本研究建立个体模型,模拟风力驱动的科尔沁沙地疏林榆树种子扩散。研究发现:各风向上种子扩散呈现单峰分布的特征,其峰值在距离种子源3~4个单位处;种子扩散距离与种子累积数量在各风向上差别不大。这一结果与野外观测结果一致。本研究表明,个体模型是研究种子扩散过程及其影响因素的有力工具。研究结果有助于理解科尔沁沙地榆树疏林天然更新过程,为植被恢复提供依据。

Seed dispersal plays an important role in the natural regeneration of elm （Ulmus pumilaL.） in sparse woodlands. To explore the effects of wind on seed dispersal of elm, an individual based model was build to simulate wind-driven seed dispersal. The results showed that in all wind directions, seed number increased along with the increase of distance and reached the peak at the 3-4 steps （cells）, and then seed number decreased. Furthermore, the seed dispersal distance and accumulation in seed number were almost the same in all wind directions. Our results suggest that individual based model is a useful tool to explore seed dispersal process and its influencing factors. Our results are helpful for understanding the regeneration of elm in sparse woodland steppe and thus providing basis for vegetation restoration in the Horqin Sandy Land.