Temporally varying larval settlement, competition, and coexistence in a sessile invertebrate community
Temporally varying larval settlement, competition, and coexistence in a sessile invertebrate community
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固着无脊椎动物群落中幼虫定居、竞争和共存的时间变化
DOI：
10.3354/meps09828
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发表时间：
2012
影响因子：
2.5
通讯作者：
J. Stachowicz
中科院分区：
文献类型：
--
作者：
K. Edwards;J. Stachowicz
储存效应理论描述了补充波动可以促进竞争单一资源的多个物种共存的条件。在底栖海洋动物群落中，幼体沉降往往变化很大，长期以来人们一直怀疑沉降变化通过储存效应促进共存，但没有实证研究为此提供定量支持。在这里，我们使用苔藓动物 Watersipora subtorquata 测试了储存效应的一个必要组成部分，该动物在招募过程中是一个较差的竞争对手。我们发现，从2008年到2009年，W. subtorquata的人均定居量与招募过程中种间竞争的强度不相关；这意味着储存效应有可能促进该物种的持久存在。我们还发现年份之间的波动模式存在差异。 2008年，沉降和竞争不相关，而2009年，沉降和竞争呈强烈正相关，从而最大限度地减少了2009年储存效应的作用。年份之间的差异是由于2009年主要竞争对手的沉降减少，其沉降物候与Watersipora不同。我们的结果为陆地植物和浮游动物的储存效应提供了支持证据，同时表明这种机制的强度本身可能会随时间变化。
Storage effect theory describes conditions under which recruitment fluctuation can promote the coexistence of multiple species competing for a single resource. In communities of benthic marine animals, larval settlement is often highly variable, and it has long been suspected that settlement variability promotes coexistence via the storage effect, but no empirical studies have provided quantitative support for this. Here we tested for a necessary component of the storage effect using the bryozoan Watersipora subtorquata, a poor competitor during recruitment. We found that from 2008 to 2009, per capita settlement of W. subtorquata was uncorrelated with the strength of interspecific competition during recruitment; this implies that the storage effect has the potential to promote the persistence of this species. We also found a difference between years in patterns of within-year fluctuation. In 2008, settlement and competition were uncorrelated, while in 2009, settlement and competition were strongly positively correlated, minimizing any role for the storage effect within 2009. The difference between years is due to reduced settlement, in 2009, of a dominant competitor whose settlement phenology differs from that of Watersipora. Our results add to supporting evidence for the storage effect from terrestrial plants and zooplankton, while suggesting that the strength of this mechanism may itself be temporally variable.