1. In plants, long-distance dispersal (LDD) is a widespread phenomenon of great importance, especially in spatial dynamics such as in metapopulations, invasions and migration. Much has become known about the mechanisms underlying LDD by wind, but selective release mechanisms have received little attention. Recent papers call for particular effort in clarification of the seed release stage of the dispersal process, which is our aim here.\ud\ud2. We studied non-random seed release at a range of spatial scales, from the individual plant to species' spatial dynamics. We did this by combining wind tunnel experiments, field trap data and simulation and analytical models, using two common wind-dispersed heathland plants (Calluna vulgaris and Erica cinerea) as study species.\ud\ud3. In both species, seed release from the plant increases with increasing wind velocity. There is a minimum release threshold, above which the probability of seed release increases with increasing wind velocity. The drag caused by the wind is the motive force for seed release.\ud\ud4. Simulations of seed dispersal with non-random seed release match measured dispersal kernels better, especially in the tails, than 'conventional' simulations with random seed release. Seed release during gusts gives the most realistic kernel. This result matches previous findings that seeds are released primarily at the start of gusts and during turbulent wind flow.\ud\ud5. Dispersal kernels assuming non-random seed release had large impacts on analytically modelled population migration rates. Wavespeeds assuming seed release during gusts were, on average, more than double those assuming random seed release. Increases in wavespeeds under different seed release assumptions were due mostly to increases in the tail of the dispersal kernel.\ud\ud6. Synthesis. This study shows how the small-scale process of a seed being released from the plant could affect the large-scale spatial dynamics of plant species in landscapes. The mechanism of non-random seed release, i.e., seed release during gusts, is an important mechanism for attaining LDD by wind. As such, non-random seed release influences landscape-scale species dynamics such as invasions and migration\ud
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机译：1.在植物中，长距离扩散（LDD）是一种非常重要的普遍现象，特别是在空间动力学中，例如在种群，入侵和迁移中。关于风驱散LDD的机制已广为人知，但选择性释放机制却鲜有关注。最近的论文呼吁为澄清分散过程的种子释放阶段做出特别的努力，这是我们的目标。\ ud \ ud2。我们研究了从单个植物到物种空间动态的一系列空间尺度上的非随机种子释放。我们通过结合风洞实验，野外圈闭数据以及模拟和分析模型，使用两种常见的分散在风中的欧石南丛生植物（Calluna vulgaris和Erica cinerea）作为研究物种来做到这一点。在这两个物种中，植物的种子释放随风速的增加而增加。有一个最小释放阈值，高于该阈值时，种子释放的可能性会随风速的增加而增加。风引起的阻力是种子释放的动力。与使用随机种子释放的“常规”模拟相比，使用非随机种子释放的种子传播模拟可以更好地匹配分散核，尤其是在尾部。阵风期间的种子释放提供了最真实的内核。此结果与以前的发现相符，即种子主要在阵风开始时和在湍流中释放。\ ud \ ud5。假设非随机种子释放的散粒对分析模型化的人口迁移率有很大影响。平均而言，假定阵风期间种子释放的波速是假定随机种子释放的波速的两倍以上。在不同的种子释放假设下，波速的增加主要归因于分散核尾部的增加。合成。这项研究表明，从植物中释放种子的小规模过程如何影响景观中植物物种的大规模空间动态。非随机种子释放的机制，即阵风期间的种子释放，是通过风获得LDD的重要机制。因此，非随机种子释放会影响景观规模的物种动态，例如入侵和迁移\ ud
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