Limiting resources in sessile systems: food enhances diversity and growth of suspension feeders despite available space.
Limiting resources in sessile systems: food enhances diversity and growth of suspension feeders despite available space.
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限制固着系统中的资源：尽管有可用空间，食物仍会增强悬浮饲养者的多样性和生长。
作者：
Robin Svensson;D. Marshall
我们对竞争的理解大部分来自于对诸如雨林和海洋无脊椎动物群落之类的群落系统的保护。在陆地系统中，固着物种经常竞争多种限制性资源（即，空间、光和营养物），但在海洋系统中，空间被视为主要或唯一的限制性资源。另一方面，竞争理论表明，对单一限制性资源的竞争不太可能维持物种的高度多样性，但对海洋底栖系统中其他资源的竞争进行操纵性测试的情况极为罕见。在这里，我们操纵一个经典的系统，海洋固着无脊椎动物群落的食物的可用性，并调查物种多样性，丰度和组成的影响，在早期的继承以及苔藓虫种群的增长领域。我们发现物种的数量是更大的，可用空间是较低的，和社区组成是不同的组合受到增加的食物供应相比，控制。同样，实验室定居的苔藓虫部署到外地增长更多的存在增强食品。我们的研究结果表明，食物可以作为一种限制性资源，影响多样性和丰富性，即使在裸露的空间仍然可以在硬基层社区。因此，将资源限制的观点扩大到空间之外，可能会增加我们对海洋固着系统的了解和可预测性。
Much of our understanding of competition comes trom onservations in sessue systems, such as rainforests and marine invertebrate communities. In terrestrial systems, sessile species often compete for multiple limiting resources (i.e., space, light, and nutrients), but in marine systems, space is viewed as the primary or sole limiting resource. Competition theory, on the other hand, suggests that competition for a single limiting resource is unlikely to maintain high species diversity, but manipulative tests of competition for other resources in marine benthic systems are exceedingly rare. Here, we manipulate the availability of food for a classic system, marine sessile invertebrate communities, and investigate the effects on species diversity, abundance, and composition during early succession as well as on the growth of bryozoan populations in the field. We found the number of species to be greater, available space to be lower, and the community composition to be different in assemblages subjected to increased food availability compared to controls. Similarly, laboratory-settled bryozoans deployed into the field grew more in the presence of enhanced food. Our results suggest that food can act as a limiting resource, affecting both diversity and abundance, even when bare space is still available in hard-substratum communities. Consequently, broadening the view of resource limitation beyond solely space may increase our understanding and predictability of marine sessile systems.