Quinn James F
Department of Zoology, University of Washington, 98195, Seattle, Washington, USA.
Oecologia. 1982 Jan;54(1):129-135. doi: 10.1007/BF00541119.
Patterns of competitive displacement by over-growth were examined in communities of sessile organisms in the low intertidal zone at three sites in Washington state and Alaska. Cruotose invertebrates and algae can be arranged into a hierarchy such that species of lower competitive rank rarely overgrow any higher ranking species. Erect and solitary species show a wide range of competitive abilities, but whether they fall into a strict hierarchy is unknown. Few of the solitary or erect species occupy substantial amounts of space in the communities examined.An approximate competitive hierarchy is well established in middle to high intertidal areas dominated by mussels, fleshy algae, and barncles, and has been an important concept in developing both an intuitive understanding and specific mathematical models of the dynamics of benthic marine communities. In particular, lower ranking species in such communities are thought to depend upon predation or chronic disturbance to the dominants to avoid competitive displacement. An alternative viewpoint, proposed on the basis of "nonstransitive" competitive relationships observed in cryptic encrusting communities on the undersides of coral plates, is that specific competitive "loops" or "networks" allow the coexistence of a number of competitors. Although the growth forms and higher taxa represented in the low intertidal bear some similarity to those in the cryptic coral reef community, there is little evidence of ecologically important competitive loops in the intertidal. A reanalysis of data from cryptic reef communities suggests that they also do not depart substantially from a competitive hierarchy, although there appear to be many more cases of local reversals in the outcome of competition. It is suggested that the ecological importance of departures from a strict hierarchy depends upon the competitive rankings of the participants, with departures involving competitively dominant species likely to contribute much more to community structure than those involving opportunistic species.
在华盛顿州和阿拉斯加的三个地点，对低潮间带固着生物群落中因过度生长导致的竞争取代模式进行了研究。壳状无脊椎动物和藻类可以排列成一个等级体系，使得竞争等级较低的物种很少能覆盖任何竞争等级较高的物种。直立和单独生长的物种表现出广泛的竞争能力，但它们是否形成严格的等级体系尚不清楚。在所研究的群落中，很少有单独或直立生长的物种占据大量空间。
在以贻贝、肉质藻类和藤壶为主的中高潮间带区域，一个大致的竞争等级体系已得到充分确立，并且在形成对底栖海洋群落动态的直观理解和特定数学模型方面一直是一个重要概念。特别是，这类群落中竞争等级较低的物种被认为依赖于捕食或对优势物种的长期干扰来避免竞争取代。基于在珊瑚板底面隐蔽的覆盖群落中观察到的“非传递性”竞争关系提出的另一种观点是，特定的竞争“环”或“网络”允许许多竞争者共存。尽管低潮间带的生长形式和较高分类单元与隐蔽的珊瑚礁群落中的有些相似，但在潮间带几乎没有生态上重要的竞争环的证据。对隐蔽珊瑚礁群落数据的重新分析表明，尽管竞争结果似乎有更多局部逆转的情况，但它们也没有明显偏离竞争等级体系。有人提出，偏离严格等级体系的生态重要性取决于参与者的竞争等级，涉及竞争优势物种的偏离可能比涉及机会主义物种的偏离对群落结构的贡献大得多。
