Patterns of seed dispersal and seed mortality inuence the spatial structure of plant communities and the local coexistence of competing species. Most seeds are dispersed in proximity to the parent tree, where mortality is also expected to be the highest, due to competition with siblings or the attraction of natural enemies. Whereas distance-dependent mortality in the seed-to-seedling transition was often observed in tropical forests, few studies have attempted to estimate the shape of the survival-distance curves, which determines whether the peak of seedling establishment occurs away from the parent tree (Janzen-Connell pattern) or if the peak attenuates but remains at the parent location (Hubbell pattern). In this study, we inferred the probability density of seed dispersal and two stages of seedling establishment (new recruits, and seedlings 20 cm or taller) with distance for 24 tree species present in the 50-ha Forest Dynamics Plot of Barro Colorado Island, Panama. Using data from seed traps, seedling survey quadrats and tree census records spanning the 1988-2014 period, we fit hierarchical Bayesian models including parameters for tree fecundity, the shape of the dispersal kernel, and overdispersion of seed or seedling counts. We combined predictions from multiple dispersal kernels to obtain more robust inferences. We find that Hubbell patterns are the most common and Janzen-Connell patterns are very rare among those species; that distance-dependent mortality may be stronger in the seed stage, in the early recruit stage, or comparable in both; and that species with larger seeds experience less overall mortality and less distance-dependent mortality. Finally, we describe how this modelling approach could be extended at a community scale to include less abundant species.

中文翻译：

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在新热带森林中，种子到幼苗的转变表现出依赖于距离的死亡率，但没有强烈的间距效应

种子传播和种子死亡率的模式影响植物群落的空间结构和竞争物种的局部共存。大多数种子分散在亲本树附近，由于与兄弟姐妹的竞争或天敌的吸引，预计这里的死亡率也最高。虽然在热带森林中经常观察到种子到幼苗过渡中的距离依赖性死亡率，但很少有研究试图估计存活距离曲线的形状，这决定了幼苗建立的高峰是否发生在远离母树的地方。 Janzen-Connell 模式）或者如果峰值衰减但保留在父位置（Hubbell 模式）。在这项研究中，我们推断了种子传播的概率密度和幼苗建立的两个阶段（新兵、和 20 厘米或更高的幼苗）与巴拿马巴罗科罗拉多岛 50 公顷森林动态图中存在的 24 种树种的距离。使用来自 1988 年至 2014 年期间的种子陷阱、幼苗调查样方和树木普查记录的数据，我们拟合了分层贝叶斯模型，包括树木繁殖力参数、扩散核的形状以及种子或幼苗计数的过度分散。我们结合了来自多个分散核的预测，以获得更可靠的推论。我们发现在这些物种中，Hubbell 模式是最常见的，而 Janzen-Connell 模式非常罕见；与距离相关的死亡率可能在种子阶段、早期招募阶段或两者相当；并且具有较大种子的物种的总体死亡率和距离依赖性死亡率较低。最后，