Submarine canyons are often morphologically complex features in the deep sea contributing to habitat heterogeneity. In addition, they act as major conduits of organic matter from the shallow productive shelf to the food deprived deep-sea, promoting gradients in food resources and areas of sediment resuspension and deposition. This study focuses on the Baltimore and Norfolk canyons, in the western North Atlantic Ocean, and investigates how different biogeochemical drivers influence canyon and slope macrofaunal communities. Replicated sediment cores were collected along the main axes (~180–1200 m) of Baltimore and Norfolk canyons and at comparable depths on the adjacent slopes. Cores were sorted, assessing whole community macrofaunal (>300 μm) abundance, diversity and standing stocks. Canyon communities were significantly different from slope communities in terms of diversity, abundance patterns and community assemblages, which were attributed to high levels of organic matter enrichment within canyons. There was a significant departure from the expected density-depth relationship in both canyons, driven by enhanced abundances between 800 and 900 m canyon depths, which was characterised as a deposition zone for organic matter. Bathymetric zonation, sediment dynamics, organic enrichment, and disturbance events were clear factors that structured the benthic communities in both Baltimore and Norfolk canyons. Coupling family-level community data, with sediment grain-size and biogeochemistry data explained community dynamics across depth and biogeochemical gradients, providing further evidence that canyons disrupt macrofaunal diversity and density patterns in the deep-sea benthos.

海底峡谷在深海中通常是形态复杂的特征，导致栖息地异质性。此外，它们是有机物从浅层生产陆架到深海被剥夺食物的主要渠道，促进了食物资源和沉积物重悬和沉积区域的梯度。这项研究的重点是北大西洋西部的巴尔的摩和诺福克峡谷，并研究了不同的生物地球化学驱动因素如何影响峡谷和斜坡大型动物群落。沿巴尔的摩和诺福克峡谷的主轴线（约180-1200 m）以及邻近斜坡上可比较的深度收集了重复的沉积物核。对核心进行了分类，评估了整个社区的大型动物（> 300μm）的丰度，多样性和常规种群。峡谷群落在多样性，丰度模式和群落集合方面与斜坡群落有显着差异，这归因于峡谷内高水平的有机物富集。在两个峡谷中，预期的密度-深度关系有很大的偏离，这是由于峡谷深度在800至900 m之间的丰度增加而引起的，该深度被认为是有机质的沉积区。水深区划，沉积物动力学，有机质富集和扰动事件是构成巴尔的摩和诺福克峡谷底栖生物群落的明显因素。结合家庭水平的社区数据，沉积物粒度和生物地球化学数据，可以解释深度和生物地球化学梯度范围内的社区动态，