RAPID: Collaborative Research: Deepwater Horizon Oil Spill, Marine Snow and Sedimentation

2010年4月，英国石油公司在墨西哥湾的油井发生事故，导致了规模和后果空前的石油泄漏。5月初在事故现场收集的初步数据显示，水中的海洋雪浓度非常高，特别是在靠近石油/分散剂的地方。该项目的目标是评估这些巨大的海洋雪状颗粒在接下来的几周到几个月内在生态系统中所起的作用。形成机制和聚集体组成都不为人所知。这些研究人员将监测海洋雪的分布，描述这些颗粒的特征，并测量沉积速率，以试图了解雪的形成和沉积在生态系统响应中的作用。这些海洋雪状聚集体的特征和潜在命运是未知的，它们可能会下沉或漂浮，被放牧，退化或长时间悬浮在水中。这次事故是一个评估和扩展我们对海洋生态系统对这种大扰动的反应的知识的机会，更具体地说，是研究聚集和沉积在这一过程中的作用的机会。海洋雪的形成及其沉积是元素循环的重要组成部分。据推测，物质的沉降会“清除”水柱中的颗粒。海洋雪也被认为是微生物活动的热点。这种含油的海洋雪不仅可能代表石油降解生物的活动热点，而且还可能起到将石油分离成小体积的作用。然而，这种油聚集体的快速沉积可能导致深海缺氧。从科学上讲，我们不了解海洋雪、海洋颗粒、石油和分散剂之间可能的相互作用。更广泛的影响了解这次迄今为止最大的石油泄漏对生态系统和生物化学循环的影响是不言而喻的。需要评估灾难的后果和附带的清理措施（例如分发分散剂），以指导进一步的调解措施，并制定和改进今后对类似灾害的反应。如果这些石油聚集物下沉，还是应该保持悬浮状态，是有利的呢？一旦我们了解了它们目前的形成和命运，可能就可以制定措施来增强下沉或悬浮（例如，添加压载矿物）。了解大量石油和分散剂进入水中后的颗粒动力学是制定当前和未来应对策略的先决条件。

The accident at the BP oil well in the Gulf of Mexico in April 2010 resulted in an oil spill of unprecedented magnitude and consequences. Preliminary data collected in the beginning of May at the site of the accident show very high concentrations of marine snow in the water, especially in close proximity to the oil/ dispersants. The goal of this project is to evaluate the role these large marine snow-like particles play in the ecosystem during the following weeks to months. Neither the formation mechanisms nor the aggregate composition are known. These investigators will monitor the distribution of marine snow, characterize these particles and measure sedimentation rates to try to understand the role of snow formation and sedimentation in the ecosystem response.Intellectual MeritThe characteristics and the potential fate of these marine snow like aggregates, which may potentially sink or float, be grazed, degraded or remain suspended in the water for a long period of time, is unknown. This accident is an opportunity to evaluate and expand our knowledge on reactions of marine ecosystems to such large disturbances in general and more specifically to study the role of aggregation and sedimentation in the process. Marine snow formation and its sedimentation are an essential component of elemental cycling. It has been postulated that sedimentation of material "cleans" the water column from particles. Marine snow is also thought to be hotspots of microbial activity. Potentially this oily marine snow could not only represent hotspots of activity for oil degrading organisms, but may also function to isolate oil into small volumes. However, rapid sedimentation of such oil aggregates may lead to anoxia at depths. Scientifically we do not understand the possible interactions between marine snow, marine particles, oil and dispersant.Broader ImpactsThe need to understand the impact of this largest oil spill to date on ecosystems and biochemical cycling is self evident. The consequences of the disaster and accompanying clean up measures (e.g. the distribution of dispersants) need to be evaluated to guide further mediating measures and to develop and improve responses to similar disasters in the future. Would it be advantageous if such oil aggregates sink, or should it rather remain suspended? Possibly measures can be developed to enhance sinking or suspension (e.g. addition of ballast minerals) once we understand their current formation and fate. Understanding the particle dynamics following the input of large amounts of oil and dispersants into the water is a prerequisite to develop response strategies for now and in the future.