An Alternative Framework to Assess Marine Ecosystem Functioning in Shelf Seas (AlterEco)

评估陆架海海洋生态系统功能的替代框架 (AlterEco)

• 批准号: NE/P013910/1
• 负责人: Timothy Smyth
• 金额: $ 12.94万
• 依托单位: Plymouth Marine Laboratory
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FP013910%2F1
• 关键词: Alternative; Framework; Assess; Marine; Ecosystem; Alternative; Framework; Assess; Marine; Ecosystem

Continental shelf seas are typically less than 200m deep and can be described by the shallow ocean surrounding continental land masses. Due to their accessibility, shelf seas are commercially and economically important, with oil and gas extraction alone in UK shelf seas valued at £37B pa. Despite occupying only 7% of the surface ocean, shelf seas also play a major role in the global carbon cycle and marine ecosystem. Shelf seas are 3-4 times more productive than open-ocean, are estimated to support more than 40% of carbon sequestration and support 90% of global fish catches providing a critical food source for growing coastal populations. However, shelf seas are also exposed to climate driven and anthropogenic stress that could have a profound impact on their biological productivity, oxygen dynamics and ecosystem function. Many processes contributing to this threat are related to regions that undergo vertical stratification. This process occurs when the bottom layer of shelf seas becomes detached from the atmospherically ventilated near surface layer. In temperate shelf seas stratification predominantly occurs as solar heating outcompetes the tide and wind-driven mixing to produce a warm surface layer, resulting in seasonal stratification over large areas of the NW European shelf seas. A combination of physical detachment from the surface and increased biological oxygen consumption in the bottom layer, accentuated by the enhanced productivity that stratification also supports in the upper ocean, can result in a drastically reduced bottom layer oxygen concentration. When oxygen levels get so low, they are classified as being oxygen deficient and this can be problematic for benthic and pelagic marine organisms and have a detrimental effect on ecosystem function. Evidence of increasing seasonal oxygen deficiency in the regions of North Sea by members of the AlterEco team and a recognised global increase in the extent of shelf sea and coastal oxygen deficiency calls for an urgent need to increase the spatial and temporal measurement of oxygen and a better understanding of the processes that lead to oxygen deficiency in shelf sea bottom waters. This need is severely impeded by the natural complexity of ecosystem functioning, the impact of a changing climate, connectivity between different regions of our shelf seas and large-scale external forcing from ocean and atmosphere. Current methods are severely restricted in resolving this complexity, due to the poor resolution in observational coverage, which calls for a new strategy for observing and monitoring marine ecosystem and environmental status.AlterEco seeks to address this challenge within the framework of the given call by the development of a novel monitoring framework to deliver improved understanding of key shelf sea ecosystem drivers. We will capitalise on recent UK investments in marine autonomous vehicles and planning capability to investigate an area of the North Sea known to undergo variable physical, chemical and biological conditions throughout an entire seasonal cycle, including areas identified to experience low bottom layer oxygen levels during summer months. Ocean gliders will be used to undertake repeat transects over a distance of ~150km, sufficient to capture important shelf sea features; such as fronts and eddies. The AlterEco strategy will employ small fleets of vehicles to capture these meso-scale features (typically ~100km in scale) but will also resolve sub-mesoscale variability (~100m). We will benefit from successes and lessons learnt from recent, pioneering deployments of underwater gliders and use a suite of sensors that permit high-resolution coincident measurements of key ecosystem indicators. Combining the expertise within the AlterEco team we will not only provide a new framework for marine observations that has global transferability, but also the diagnostic capability to improve understanding of shelf sea ecosystem health and function.

大陆架海洋通常不到200m深度，可以用连续土地的浅海来描述。由于它们的可及性，货架海在商业和经济上都很重要，仅英国货架海洋的石油和天然气提取价值为37B英镑。尽管仅占据地表海的7％，但货架海在全球碳循环和海洋生态系统中也起着重要作用。货架海的生产力是开放式海洋的3-4倍，据估计可以支持40％以上的碳固存，并支持90％的全球鱼类捕获，为沿海人群增长的关键食物来源。然而，货架海也暴露于气候驱动和人为应力，可能会对其生物生产力，氧动力学和生态系统功能产生深远影响。导致这种威胁的许多过程与经历垂直分层的地区有关。当架子海洋的底层从地面层附近的大气通风中脱离时，就会发生这种过程。在温度架子的海洋中，主要是由于太阳能加热胜过潮汐和风驱动的混合以产生温暖的表面层，从而在西北欧洲陆架海洋的大面积上产生季节性分层。从表面上的物理脱离与底层中生物氧的消耗增加的结合，这是由于分层也支持上海的生产力增强，可能会导致底层氧浓度大大降低。当氧气水平如此之低时，它们被归类为缺氧缺乏，这对于底栖和骨髓海洋生物可能是有问题的，并且对生态系统功能产生不利影响。 Altereco团队成员在北海地区增加季节性缺乏症的证据，以及公认的货架海和沿海氧不足程度的全球增加，需要迫切需要增加氧气的空间和临时测量，并更好地理解该过程，从而导致Shelf Sea Bouts Waters的氧气缺乏症。生态系统功能的自然复杂性，气候变化的影响，架子海洋不同地区之间的连通性以及从海洋和大气中的大规模外部强迫的影响，严重阻碍了这种需求。由于观察覆盖率的分辨率不佳，目前的方法在解决这种复杂性方面受到严格限制，该方法要求采取新的策略，以进行观察和监测海洋生态系统和环境状况。Altereco试图通过新的监测框架开发给定的挑战，以在给定呼叫的框架内解决这个新颖的监测框架，以提供对钥匙架海洋生态系统驱动器的改进的了解。我们将利用最近对海洋自动驾驶汽车的投资，并计划在整个季节性周期中调查北海地区经历可变的物理，化学和生物学状况的区域，包括在夏季经历低底层氧气水平的区域。海洋滑翔机将用于在约150公里的距离内进行重复样品，足以捕获重要的架子海特征；例如前部和涡流。 Altereco策略将雇用小型车辆捕获这些中尺度的特征（通常规模〜100公里），但也将解决子尺度尺度尺度的可变性（约100m）。我们将从最新的，开创性的水下滑翔机部署中学到的成功和教训中受益，并使用一套传感器，这些传感器可以允许对关键生态系统指标进行高分辨率重合测量。结合了Altereco团队中的专业知识，我们不仅将为具有全球可转移性的海洋观察提供一个新的框架，而且还将为提高对货架海生态系统健康和功能的了解的诊断能力。