Lipids and their degradation products were investigated in samples of suspended particulate matter (SPM) collected in summer 2015 from surface waters of a South-North transect (ca. 65–81°N) of the Chukchi Sea. This material appeared to be composed mainly of diatoms (dominated by Thalassiosirales) and copepod faecal pellet debris. The high solar irradiances measured in the surface waters (up to 500 W m⁻²) favour chlorophyll (sensitizer) photobleaching at the expense of Type II photosensitized oxidation of unsaturated lipid components of phyto- and zooplankton (photodynamic effect). The weak photoreactivity of wax esters of herbivorous zooplankton in these SPM samples contrasts with previous observations of strong photooxidation of these compounds in sinking particles, which suggests that the photodynamic effect should be favoured in large faecal pellets of herbivorous copepods sinking quickly in weakly irradiated zones. Autoxidation (free radical induced oxidation) processes operating in all oxic environments appeared to be particularly efficient in faecal pellets of omnivorous and carnivorous zooplankton and limited in those of herbivorous origin. These differences were attributed to the consumption of algal antioxidants (such as mycosporine-like amino acids and carotenoids) during the diet of omnivorous and carnivorous copepods, favouring the involvement of free radical oxidation processes.

在 2015 年夏季从楚科奇海南北横断面（约 65-81°N）的地表水中采集的悬浮颗粒物 (SPM) 样品中研究了脂质及其降解产物。这种材料似乎主要由硅藻（以海藻目为主）和桡足类粪便颗粒碎片组成。在地表水中测得的高太阳辐照度（高达 500 W m ^-2) 有利于叶绿素（敏化剂）光漂白，而牺牲了对浮游植物和浮游动物的不饱和脂质成分的 II 型光敏氧化（光动力效应）。这些 SPM 样品中草食性浮游动物蜡酯的弱光反应性与之前观察到的这些化合物在下沉颗粒中的强光氧化形成对比，这表明光动力效应应该有利于草食性桡足类的大粪便颗粒在弱辐照区域快速下沉。在所有有氧环境中进行的自氧化（自由基诱导的氧化）过程似乎对杂食性和肉食性浮游动物的粪便颗粒特别有效，而在草食性动物的粪便颗粒中则受到限制。