Bloom and bust: seasonal cycles of phytoplankton and carbon flux

繁荣与萧条：浮游植物和碳通量的季节性周期

• 批准号: 2910180
• 金额: --
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2910180
• 关键词: Bloom; bust; seasonal; cycles; phytoplankton

CO2 taken up from the atmosphere by biological processes in the ocean is transferred into the deep ocean mostly in the form of sinking particles. Without this "biological carbon pump", atmospheric CO2 would be 50% higher than it already is. Despite its importance, our understanding is limited by scarce ship-board observations, especially how particulate organic carbon (POC) fluxes vary over days to seasons. However, a growing network of underwater robots are opening the door for high-resolution observations of these sinking particles. Gliders are unmanned autonomous vehicles that make measurements over weeks to months, including optical backscatter data which can be used to estimate POC fluxes. At PAP, one of the UK's long-term observing sites, we have collected data from multiple glider missions, including in collaboration with colleagues at NASA. These data will allow important unresolved questions to be addressed: How do fluxes vary seasonally in relation to phytoplankton blooms? How episodic are the fluxes? What are the implications for characterizing global-scale organic carbon fluxes? (Bol et al., 2018; Henson et al., 2015) Filling this gap will allow better predictions of how this important planetary carbon flux is linked to productivity and how it responds to variability in the environment. The project will initially use data obtained from gliders during past missions at PAP, such as OSMOSIS [1] and EXPORTS to determine the temporal patterns in POC fluxes, their attenuation with depth, and how this relates to phytoplankton blooms. Glider-derived optical backscatter data will be transformed into estimates of POC concentration and flux, using protocols established by co-supervisor Briggs [2]. Different metrics to characterise the fraction of POC flux reaching the mesopelagic zone will be calculated. Your initial analysis will focus on establishing the temporal patterns of phytoplankton blooms, flux and attenuation, before moving on to assessing how interannual variability in physical conditions may alter the relationship between primary production and fluxes. Depending on your interests, subsequent work may include exploiting additional autonomous technologies to study particular processes, e.g. particle fragmentation [2], other locations in more detail, satellite data to broaden the study to larger spatial and temporal scales, or using global biogeochemical models to explore the mechanisms and patterns of variability in POC fluxes. If interested, you may participate in the planning and deployment of more autonomous platforms for 2 upcoming funded projects (Bio-carbon and ReBELS), both aimed at better quantifying the carbon sequestration pathways in subpolar regions.

海洋中的生物过程从大气中取出的二氧化碳被转移到深海中，主要是以下沉的颗粒的形式转移到深海中。没有这种“生物碳泵”，大气二氧化碳将比以前高出50％。尽管它很重要，但我们的理解受到稀缺的船板观察的限制，尤其是颗粒有机碳（POC）通量在几天到季节的变化。但是，不断增长的水下机器人网络正在为这些下沉颗粒的高分辨率观察打开了大门。滑翔机是无人自动驾驶的车辆，可以在数周到几个月内进行测量，包括可用于估算POC通量的光学反向散射数据。在英国长期观察站点之一的PAP上，我们从多个滑翔机任务中收集了数据，包括与NASA的同事合作。这些数据将允许解决重要的未解决的问题：与浮游植物绽放有关的通量如何变化？磁通量如何？表征全球尺度有机碳通量的影响是什么？ （Bol等，2018; Henson等，2015）填补这一空白将可以更好地预测这种重要的行星碳通量与生产力以及它对环境中可变性的反应。该项目最初将使用过去在PAP的任务期间从滑翔机获得的数据，例如渗透[1]和出口来确定POC通量中的时间模式，其深度衰减以及与浮游植物盛开的关系。使用由共同参见Briggs建立的方案[2]，滑翔机衍生的光散射数据将转换为POC浓度和通量的估计值。将计算出不同的指标来表征到达中质区域的POC通量分数。您的初始分析将着重于建立浮游植物盛开，通量和衰减的时间模式，然后继续评估物理条件中的年际变化如何改变初级生产与通量之间的关系。根据您的兴趣，随后的工作可能包括利用其他自主技术来研究特定过程，例如粒子碎片[2]，其他位置，更详细地，卫星数据将研究扩大到更大的空间和时间尺度，或使用全局生物地球化学模型探索POC通量中可变性的机制和模式。如果有兴趣，您可能会为即将到来的两个资助项目（Bio-Coar和Rebels）计划和部署更多的自主平台，均旨在更好地量化子极区域中的碳固存途径。