Department of Zoology, University of Melbourne, Parkville 3010, Australia.
Ecology. 2012 May;93(5):1153-63. doi: 10.1890/11-1390.1.
The species composition, density, and frequency of recruitment into any given habitat are highly variable in most biological systems that rely on dispersive propagules (larvae, seeds, spores, etc.). There are few direct experimental studies of how recruitment variation between single species influences the composition and assembly of whole communities in many of these systems. We manipulated recruitment of a variety of single taxa and followed their effects on the subsequent development of hard-substrate communities of sessile animals living in temperate marine waters. The effects of recruitment on communities were complex. Patterns of recruitment of individual species influenced community structure, but these effects varied greatly depending on the identity of species recruits, the time of community development, and location across three different sites. Variable recruitment of arborescent bryozoans and didemnid ascidians had little effect on community structure. At one site, recruitment of the colonial ascidian Botryllus schlosseri had short-lived effects on community structure, while barnacles had more persistent effects. At another site, recruitment of B. schlosseri and the bryozoan Watersipora subtorquata had strong persistent effects on community structure, dominating space where they recruited and influencing the abundances of a variety of different taxa. Differences in the effects of species recruitment on communities appear to be caused by differences between the ecology and life history of recruiting species as well as differences in background processes between sites. These results demonstrate that discrete recruitment events that vary between single species can be important drivers of community composition but are likely to be heavily influenced by the local environment, even within a single species.
在大多数依赖分散繁殖体（幼虫、种子、孢子等）的生物系统中，任何特定栖息地的物种组成、密度和繁殖频率都高度可变。在这些系统中，很少有直接的实验研究表明，单一物种之间的繁殖变化如何影响整个群落的组成和组装。我们操纵了多种单一分类群的繁殖，并跟踪它们对生活在温带海洋水域的固着动物硬基质群落随后发展的影响。繁殖对群落的影响是复杂的。个别物种的繁殖模式影响着群落结构，但这些影响因物种的身份、群落发展的时间以及三个不同地点的位置而有很大的差异。树状苔藓动物和双壳类动物等有枝状生物的繁殖变化对群落结构几乎没有影响。在一个地点，殖民地海鞘 Botryllus schlosseri 的繁殖对群落结构有短暂的影响，而藤壶的影响则更持久。在另一个地点，B. schlosseri 和苔藓动物 Watersipora subtorquata 的繁殖对群落结构有强烈而持久的影响，它们占据了自己繁殖的空间，并影响了各种不同分类群的丰度。物种繁殖对群落的影响差异似乎是由繁殖物种的生态学和生活史差异以及不同地点之间背景过程的差异引起的。这些结果表明，不同物种之间繁殖的离散事件可能是群落组成的重要驱动因素，但即使在同一物种内，也很可能受到当地环境的严重影响。
