Landcare Research, Lincoln, 7608, New Zealand.
Centre for Ecosystem Science, University of New South Wales, Kensington, NSW, 2052, Australia.
New Phytol. 2018 Jan;217(1):407-415. doi: 10.1111/nph.14735. Epub 2017 Aug 21.
Tall plant species disperse further distances than do short species, within and across dispersal syndromes, yet the driver underpinning this relationship is unclear. The ability of taller plants to invest more in dispersal structures may explain the positive relationship between plant height and dispersal distance. Here, we quantify the cross-species relationships between presence of dispersal structures, dispersal investment plant height and dispersal distance. Plant height, dispersal syndrome and dispersal investment data were collated for 1613 species from the literature, with dispersal distance data collated for 114 species. We find that species with high dispersal investment disperse further than do species with low dispersal investment. Tall species have a greater probability of having dispersal structures on their seeds compared with short species. For species with dispersal structures on their seeds, plant height is very weakly related to dispersal investment. Our results provide the first global confirmation of the dispersal investment-distance hypothesis, and show dispersal investment can be used for predicting species dispersal distances. However, our results and those of previous studies indicate plant height is still the best proxy for estimating species dispersal distances due to it being such a readily available plant trait.
高的植物物种比矮的植物物种在同一扩散综合特征内或跨扩散综合特征的情况下能传播更远的距离，但支持这种关系的驱动力尚不清楚。较高的植物能够在扩散结构上投入更多的能力可能解释了植物高度与扩散距离之间的正相关关系。在这里，我们定量地研究了不同物种之间存在的扩散结构、扩散投入、植物高度和扩散距离之间的关系。我们从文献中收集了 1613 个物种的植物高度、扩散综合特征和扩散投入数据，以及 114 个物种的扩散距离数据。我们发现，具有高扩散投入的物种比具有低扩散投入的物种传播得更远。与矮物种相比，高物种的种子上更有可能具有扩散结构。对于具有种子扩散结构的物种，植物高度与扩散投入的关系非常微弱。我们的结果首次在全球范围内证实了扩散投入-距离假说，并表明扩散投入可以用于预测物种的扩散距离。然而，我们的结果和以前的研究表明，由于植物高度是一种易于获取的植物特征，因此它仍然是估计物种扩散距离的最佳代理变量。
