Medeiros Aline P M, Ferreira Beatrice P, Alvarado Fredy, Betancur-R Ricardo, Soares Marcelo O, Santos Bráulio A
Programa de Pós-Graduação em Ciências Biológicas Universidade Federal da Paraíba João Pessoa PB Brazil.
Departamento de Oceanografia Centro de Tecnologia Universidade Federal de Pernambuco Recife Brazil.
Ecol Evol. 2021 Mar 18;11(9):4413-4427. doi: 10.1002/ece3.7336. eCollection 2021 May.
The deep reef refugia hypothesis (DRRH) predicts that deep reef ecosystems may act as refugium for the biota of disturbed shallow waters. Because deep reefs are among the most understudied habitats on Earth, formal tests of the DRRH remain scarce. If the DRRH is valid at the community level, the diversity of species, functions, and lineages of fish communities of shallow reefs should be encapsulated in deep reefs.We tested the DRRH by assessing the taxonomic, functional, and phylogenetic diversity of 22 Brazilian fish communities between 2 and 62 m depth. We partitioned the gamma diversity of shallow (<30 m) and deep reefs (>30 m) into independent alpha and beta components, accounted for species' abundance, and assessed whether beta patterns were mostly driven by spatial turnover or nestedness.We recorded 3,821 fishes belonging to 85 species and 36 families. Contrary to DRRH expectations, only 48% of the species occurred in both shallow and deep reefs. Alpha diversity of rare species was higher in deep reefs as expected, but alpha diversity of typical and dominant species did not vary with depth. Alpha functional diversity was higher in deep reefs only for rare and typical species, but not for dominant species. Alpha phylogenetic diversity was consistently higher in deep reefs, supporting DRRH expectations.Profiles of taxonomic, functional, and phylogenetic beta diversity indicated that deep reefs were not more heterogeneous than shallow reefs, contradicting expectations of biotic homogenization near sea surface. Furthermore, pairwise beta-diversity analyses revealed that the patterns were mostly driven by spatial turnover rather than nestedness at any depth. . Although some results support the DRRH, most indicate that the shallow-water reef fish diversity is not fully encapsulated in deep reefs. Every reef contributes significantly to the regional diversity and must be managed and protected accordingly.
深海珊瑚礁避难所假说（DRRH）预测，深海珊瑚礁生态系统可能成为受干扰浅水区生物群的避难所。由于深海珊瑚礁是地球上研究最少的栖息地之一，对DRRH的正式检验仍然很少。如果DRRH在群落水平上是有效的，那么浅海珊瑚礁鱼类群落的物种、功能和谱系多样性应该在深海珊瑚礁中得到体现。我们通过评估巴西22个深度在2至62米之间的鱼类群落的分类、功能和系统发育多样性来检验DRRH。我们将浅海（<30米）和深海珊瑚礁（>30米）的伽马多样性划分为独立的阿尔法和贝塔成分，考虑了物种的丰度，并评估了贝塔模式是否主要由空间周转率或嵌套性驱动。我们记录了3821条鱼，分属85个物种和36个科。与DRRH的预期相反，只有48%的物种同时出现在浅海和深海珊瑚礁中。正如预期的那样，深海珊瑚礁中稀有物种的阿尔法多样性更高，但典型和优势物种的阿尔法多样性并不随深度变化。仅对于稀有和典型物种，深海珊瑚礁中的阿尔法功能多样性更高，而优势物种并非如此。深海珊瑚礁中的阿尔法系统发育多样性一直更高，支持了DRRH的预期。分类、功能和系统发育贝塔多样性的概况表明，深海珊瑚礁并不比浅海珊瑚礁更具异质性，这与海面附近生物同质化的预期相矛盾。此外，成对的贝塔多样性分析表明，这些模式在任何深度下主要由空间周转率而非嵌套性驱动。虽然一些结果支持DRRH，但大多数结果表明，浅水区珊瑚礁鱼类多样性并未完全体现在深海珊瑚礁中。每个珊瑚礁对区域多样性都有重要贡献，因此必须进行相应的管理和保护。
