Department of Biology, The University of North Carolina at Chapel Hill , Chapel Hill, NC , USA.
Department of Biology and Marine Biology, University of North Carolina at Wilmington , Wilmington, NC , USA.
PeerJ. 2014 Mar 18;2:e308. doi: 10.7717/peerj.308. eCollection 2014.
More diverse communities are thought to be more stable-the diversity-stability hypothesis-due to increased resistance to and recovery from disturbances. For example, high diversity can make the presence of resilient or fast growing species and key facilitations among species more likely. How natural, geographic biodiversity patterns and changes in biodiversity due to human activities mediate community-level disturbance dynamics is largely unknown, especially in diverse systems. For example, few studies have explored the role of diversity in tropical marine communities, especially at large scales. We tested the diversity-stability hypothesis by asking whether coral richness is related to resistance to and recovery from disturbances including storms, predator outbreaks, and coral bleaching on tropical coral reefs. We synthesized the results of 41 field studies conducted on 82 reefs, documenting changes in coral cover due to disturbance, across a global gradient of coral richness. Our results indicate that coral reefs in more species-rich regions were marginally less resistant to disturbance and did not recover more quickly. Coral community resistance was also highly dependent on pre-disturbance coral cover, probably due in part to the sensitivity of fast-growing and often dominant plating acroporid corals to disturbance. Our results suggest that coral communities in biodiverse regions, such as the western Pacific, may not be more resistant and resilient to natural and anthropogenic disturbances. Further analyses controlling for disturbance intensity and other drivers of coral loss and recovery could improve our understanding of the influence of diversity on community stability in coral reef ecosystems.
多样性被认为可以使群落更加稳定,这就是多样性-稳定性假说,因为多样性可以增强对干扰的抵抗力和恢复力。例如,高度的多样性可以使具有弹性或快速生长的物种和物种之间的关键促进因素更有可能存在。自然的、地理的生物多样性模式以及人类活动引起的生物多样性变化如何调节群落水平的干扰动态在很大程度上是未知的,特别是在多样性系统中。例如,很少有研究探讨多样性在热带海洋群落中的作用,尤其是在大尺度上。我们通过询问珊瑚丰富度是否与热带珊瑚礁的风暴、捕食者爆发和珊瑚白化等干扰的抵抗力和恢复力有关,来检验多样性-稳定性假说。我们综合了在全球珊瑚丰富度梯度上,对 82 个珊瑚礁进行的 41 项实地研究的结果,记录了由于干扰导致的珊瑚覆盖率的变化。我们的结果表明,物种丰富度较高的地区的珊瑚礁对干扰的抵抗力略有降低,恢复速度也没有更快。珊瑚群落的抵抗力也高度依赖于干扰前的珊瑚覆盖率,这可能部分是由于快速生长且通常占主导地位的平板鹿角珊瑚对干扰的敏感性。我们的结果表明,在生物多样性丰富的地区,如西太平洋,珊瑚群落可能对自然和人为干扰的抵抗力和恢复力并不更强。进一步分析控制干扰强度和其他珊瑚丧失和恢复的驱动因素,可以提高我们对多样性对珊瑚礁生态系统群落稳定性影响的理解。