Paxton Avery B, Pickering Emily A, Adler Alyssa M, Taylor J Christopher, Peterson Charles H
Institute of Marine Sciences, University of North Carolina at Chapel Hill, Morehead City, North Carolina, United States of America.
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
PLoS One. 2017 Sep 5;12(9):e0183906. doi: 10.1371/journal.pone.0183906. eCollection 2017.
Structural complexity, a form of habitat heterogeneity, influences the structure and function of ecological communities, generally supporting increased species density, richness, and diversity. Recent research, however, suggests the most complex habitats may not harbor the highest density of individuals and number of species, especially in areas with elevated human influence. Understanding nuances in relationships between habitat heterogeneity and ecological communities is warranted to guide habitat-focused conservation and management efforts. We conducted fish and structural habitat surveys of thirty warm-temperate reefs on the southeastern US continental shelf to quantify how structural complexity influences fish communities. We found that intermediate complexity maximizes fish abundance on natural and artificial reefs, as well as species richness on natural reefs, challenging the current paradigm that abundance and other fish community metrics increase with increasing complexity. Naturally occurring rocky reefs of flat and complex morphologies supported equivalent abundance, biomass, species richness, and community composition of fishes. For flat and complex morphologies of rocky reefs to receive equal consideration as essential fish habitat (EFH), special attention should be given to detecting pavement type rocky reefs because their ephemeral nature makes them difficult to detect with typical seafloor mapping methods. Artificial reefs of intermediate complexity also maximized fish abundance, but human-made structures composed of low-lying concrete and metal ships differed in community types, with less complex, concrete structures supporting lower numbers of fishes classified largely as demersal species and metal ships protruding into the water column harboring higher numbers of fishes, including more pelagic species. Results of this study are essential to the process of evaluating habitat function provided by different types and shapes of reefs on the seafloor so that all EFH across a wide range of habitat complexity may be accurately identified and properly managed.
结构复杂性作为栖息地异质性的一种形式，会影响生态群落的结构和功能，通常能支持物种密度、丰富度和多样性的增加。然而，最近的研究表明，最复杂的栖息地可能并不拥有最高的个体密度和物种数量，尤其是在人类影响较大的地区。有必要了解栖息地异质性与生态群落之间关系的细微差别，以指导以栖息地为重点的保护和管理工作。我们对美国东南大陆架上的30个暖温带珊瑚礁进行了鱼类和结构栖息地调查，以量化结构复杂性如何影响鱼类群落。我们发现，中等复杂性能使天然和人工珊瑚礁上的鱼类丰度最大化，以及天然珊瑚礁上的物种丰富度最大化，这对当前认为丰度和其他鱼类群落指标会随着复杂性增加而增加的范式提出了挑战。形态平坦和复杂的天然岩石礁支持着相等的鱼类丰度、生物量、物种丰富度和群落组成。为了使平坦和复杂形态的岩石礁作为重要鱼类栖息地（EFH）得到同等重视，应特别注意探测铺面型岩石礁，因为它们的短暂性使得用典型的海底测绘方法难以探测到它们。中等复杂性的人工珊瑚礁也能使鱼类丰度最大化，但由低洼混凝土和金属船构成的人造结构在群落类型上有所不同，较不复杂的混凝土结构支持的鱼类数量较少，这些鱼类主要被归类为底栖物种，而伸入水柱的金属船则栖息着更多的鱼类，包括更多的浮游物种。这项研究的结果对于评估海底不同类型和形状的珊瑚礁所提供的栖息地功能的过程至关重要，以便能够准确识别和妥善管理广泛栖息地复杂性范围内的所有重要鱼类栖息地。
