Quantitation of the Concentration of Detritus Associated with Marine Planktonic Communities

无生命颗粒有机物，称为碎屑，在水柱环境中，特别是在海洋中，对碳和宏量营养素的循环起着重要作用。对碎屑颗粒中碳结合的评估通常超过对浮游生物碳的估计，仅次于溶解的有机碳。碎屑是一种高度动态的介质，它为微生物呼吸溶解的有机碳及其转化为特定的有机碳提供了底物，也为细菌和浮游植物分泌的外聚合物的非生物缩合提供了底物。然而，就地量化碎屑的能力仍然是一个未解决的问题。拟议的研究将利用受控实验室实验调查颗粒碎屑碳（和氮）体积比的可变性。定量将使用一种新开发的荧光标记技术，然后是成像细胞术。实验室获得的数据将与大陆架水域天然浮游生物群落的实地数据进行比较。这项工作将允许精确测定颗粒碎屑和浮游生物种群大小，这是解决有机碳和氮在非生物和生物资源之间动态交换的必要前提，特别是这些物质的向下通量和营养转移。* * *

9521086 Verity Non-living particulate organic matter, called detritus, plays an important role in the cycling of carbon and macronutrients in water column environments, especially in the ocean. Assessments of carbon bound in detrital particles typically exceed estimates of carbon from plankton and are second only to dissolved organic carbon. Detritus is a highly dynamic medium which provides a substrate for microbial respiration of dissolved organic carbon and its transformation into particular organic carbon and a substrate for abiotic condensation of exopolymers, secreted from bacteria and phytoplankton. However, the ability to quantify detritus in situ has remained an unresolved problem. The proposed research will investigate variability in particulate detrital carbon (and nitrogen):volume ratios using controlled laboratory experiments. Quantification will be conducted using a newly developed fluorescent labeling technique followed by imaging cytometry. Laboratory-derived data will be compared to field data from natural plankton communities in continental shelf waters. This work will allow accurate determinations of particulate detrital and plankton stock sizes, a necessary prerequisite to resolving the dynamic interchange of organic carbon and nitrogen between non-living and living resources, especially the downward flux and trophic transfer of such materials. ***