Submarine canyons act as hotspots of biodiversity, hosting vulnerable marine ecosystems, and playing a fundamental role in bridging coastal zones with deeper areas. Here, we investigated the suprabenthic and Deep Scattering Layer (DSL) zooplankton fauna, that play a key role in deep-sea food webs, as main resources for both mobile and sessile megafauna, in two submarine canyons (Squillace and Amendolara) of the Ionian Sea (Central Mediterranean Sea). Our results highlighted different taxonomic and functional diversity between the two adjacent canyons: () biomass and abundance of suprabenthos followed an opposite trend in the two canyons, increasing both with depth in Amendolara (higher abundance and biomass in the lower part of the canyon), and decreasing with depth in Squillace (greater in the head of the canyon); () DSL zooplankton abundance and biomass followed a spatial distribution, decreasing with increasing distance from the coast for both canyons (i.e. lower offshore than at the head of the canyon). Food-web structure investigated by means of stable isotope analysis of C and N showed a more diverse trophic niche for suprabenthos than for zooplankton. Furthermore, possible feeding modes of species with unknown feeding behaviour have been proposed. The results of the current article highlight the different ecological processes occurring within each canyon. Understanding the spatial variations of communities inhabiting submarine canyons, especially those at the base of deep-sea food webs which can act as driver of megafaunal communities (both sessile and mobile-commercial species), is essential to focalise future conservation efforts.

中文翻译：

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深海食物网的基础：海底峡谷中底栖动物和浮游动物的聚集和营养结构


海底峡谷是生物多样性的热点，承载着脆弱的海洋生态系统，并在连接沿海地区与更深地区方面发挥着重要作用。在这里，我们研究了爱奥尼亚海两个海底峡谷（斯奎拉斯和阿门多拉拉）的底栖和深层散射层 (DSL) 浮游动物群，它们在深海食物网中发挥着关键作用，是移动和固着巨型动物群的主要资源。海（地中海中部）。我们的结果强调了两个相邻峡谷之间不同的分类和功能多样性：（）两个峡谷的底栖动物生物量和丰度呈现相反的趋势，在阿门多拉拉（峡谷下部丰度和生物量较高），两者都随着深度的增加而增加，斯奎拉斯（Squillace）的深度随着深度而减小（在峡谷的顶部更大）； () DSL 浮游动物丰度和生物量遵循空间分布，随着两个峡谷距海岸距离的增加而减少（即近海位置低于峡谷顶部）。通过碳和氮的稳定同位素分析研究的食物网结构表明，底栖动物比浮游动物具有更加多样化的营养生态位。此外，还提出了具有未知摄食行为的物种的可能摄食模式。本文的结果强调了每个峡谷内发生的不同生态过程。了解栖息在海底峡谷的群落的空间变化，特别是那些位于深海食物网底部的群落，它们可以作为巨型动物群落（固着和移动商业物种）的驱动力，对于集中未来的保护工作至关重要。