We examined the biogenic and lithogenic particle composition and radiocarbon content of sinking particulate organic carbon to investigate sediment resuspension and its contribution to sinking particles on the deep abyssal plain of the Eastern Tropical Pacific Ocean. Samples were collected using sediment traps from August 2011 to July 2012 at depths of 4500 and 4950 m (50 m above the seafloor); above and within the benthic nepheloid layer (BNL), respectively. Biogenic particles derived from export production were the major source of sinking particles and their flux showed a unimodal temporal distribution, with larger values between February and April. At a depth of 4500 m, the lithogenic material flux was slightly greater than, or similar to, the flux of atmospheric dust deposition. In comparison, lithogenic material and excess Mn consistently showed a greater contribution to resuspended particles at 4950 m. The lithogenic material flux was proportional to the biogenic flux. These observations imply that resuspended particles exist at a background concentration in the BNL throughout the year, and are scavenged by sinking biogenic particles, especially during the high flux period.

我们检查了下沉颗粒有机碳的生物和成岩颗粒组成以及放射性碳含量，以研究沉积物再悬浮及其对东热带太平洋深海平原上下沉颗粒的贡献。从 2011 年 8 月到 2012 年 7 月，使用沉积物捕集器在 4500 和 4950 m（海底上方 50 m）的深度收集样品；分别位于底栖类星体层 (BNL) 上方和内部。出口生产的生物颗粒是下沉颗粒的主要来源，其通量呈单峰时间分布，2-4 月数值较大。在4 500 m深度，岩性物质通量略大于或接近大气尘埃沉降通量。相比下，成岩物质和过量的 Mn 始终显示出对 4950 m 处的再悬浮颗粒的更大贡献。成岩物质通量与生物成因通量成正比。这些观察结果表明，再悬浮颗粒全年都以背景浓度存在于 BNL，并被下沉的生物颗粒清除，尤其是在高通量时期。