Physical and biological dynamic coastal processes and their role in coastal recovery (BLUE-coast)

蓝色海岸联盟解决了国家海岸研究中心的重点议题B--海岸形态：海岸沉积物收支及其在沿海恢复中的作用。该项目将采取全面和多学科的方法，将生物学家、沿海工程师、地质学家、地貌学家和海洋学家的专门知识结合起来，并补充实验(实地和实验室)和数值技能，以了解哪些过程控制沿海系统动力学，并回答相关的科学问题。蓝色海岸将明确解决中期(年)和长期(十年及更长)区域泥沙预算的预测中的不确定性，并通过以下方式更好地了解地形变化和海岸在风暴等一系列事件后如何恢复：(I)在模型中改善海岸带内可运输物质和来源物质的表示；(Ii)利用代表英国沿海地区的示范生境确定生态系统如何调节可运输物质；(3)评估这一混合泥沙物理和生物系统对外部强迫的可能变化的敏感性，包括多个变量和事件序列的综合影响，目的是在评估行为不确定性的同时了解系统的内部动力学(例如，非线性、临界阈值、临界点、前体和前兆条件)，以及(4)减少区域泥沙收支和形态变化中长期预测中的不确定性。为了采取综合、全面和具有成本效益的应对措施，我们的主要活动将结合：(1)对典型的大陆架海洋地貌进行详细研究，包括通常在温带海岸观察到的各种生物-沉积物条件；(2)关键过程的现场验证研究；(3)旨在明确确定因果关系和确定一般性的操纵性实验室和实地实验；(4)整合对区域尺度和环境胁迫下的沿海地貌动力学的控制和影响的新认识。通过进行大量的现场观测和过程研究，我们将直接量化先前条件对海岸侵蚀和恢复的影响，生物群对调节沉积物通量和路径的影响，以及事件排序对一系列具有重要地理意义的沉积物生境的海岸侵蚀和恢复的影响。这些数据将作为现有和创新数值模型的校准和验证数据集，这些模型将能够单独或组合模拟关键生物和物理驱动因素的沿海形态后果。我们将通过进行仔细控制的实验，使用水槽产生不同的流态，使用最先进的现场测量技术跟踪自然事件期间的变化，以及在实验室使用完整的沉积物和暴露在预期未来条件(变暖、海洋酸化、营养物质负载)下的沉积物群落，从机理上了解并实现一般性。由于以高空间分辨率量化整个英国海岸的所有相关地貌动力学过程是不可行的，我们的方法是通过遵循科学主题的逻辑发展的4个跨学科工作包来解决主要目标。

The BLUE-coast consortium addresses NERC highlight topic B, Coastal morphology: coastal sediment budgets and their role in coastal recovery. This project will adopt a holistic and multidisciplinary approach, combining the expertise of biologists, coastal engineers, geologists, geomorphologists and oceanographers with complementary experimental (field and laboratory) and numerical skills, to understand what processes control the coastal system dynamics and answer the relevant scientific questions. BLUE-coast will explicitly address uncertainties in the prediction of medium-term (years) and long -term (decadal and longer) regional sediment budgets and better understand morphological change and how the coast recovers after sequences of events, such as storms by: (i) improving representation of both transportable and source material within the coastal zone within models; (ii) establishing how transportable material is mediated by the ecological system using exemplar habitats representative of the UK coastal zone; (iii) assessing sensitivities of this mixed-sediment physical and biological system to possible changes in external forcing, including the combined impact of multiple variables and sequences of events, with the goal of understanding the internal dynamics of the system (e.g. nonlinearities, critical thresholds, tipping points, precursors and antecedent conditions) in parallel with assessments of behavioural uncertainties, and (iv) reduce uncertainties in medium to long -term prediction of regional sediment budgets and morphological change.Project Overview: the scope of the Highlight Topic sets a requirement for quantitative knowledge on both physical and biological dynamic coastal processes in order to improve hydrodynamic model predictions of regional sediment budgets and morphological change. To deliver an integrated, holistic and cost effective response, our main activities will combine (i) a detailed study of representative shelf sea landscapes that spans the full variety of organism-sediment conditions typically observed in temperate coasts, with (ii) in situ validation studies of key processes, and (iii) manipulative laboratory and field experiments aimed at unambiguously identifying causal relationships and establishing generality, and (iv) integration of new understanding of controls and effects on coastal morphodynamics at regional scales and under environmental forcing. By undertaking a substantial element of in situ observation and process studies, we will directly quantify the effect of antecedent conditions on coastal erosion and recovery, the effect of biota on mediating sediment fluxes and pathways and the effect of event sequencing on coastal erosion and recovery, across a range of geographically significant sediment habitats. These data will act as calibration and validation datasets for existing and innovative numerical models that will be able to simulate the coastal morphological consequences of key biological and physical drivers, alone and in combination. We will gain mechanistic understanding and achieve generality by performing carefully controlled experiments, generating different flow regimes using flumes, tracking changes during natural events using state-of-the-art field measurement technology and, in the laboratory, using intact sediments and sediment communities exposed to anticipated future conditions (warming, ocean acidification, nutrient loading). As it is not feasible to quantify all the relevant morphodynamic processes at high spatial resolution across the entire UK coast, our approach is to address the principal objectives through 4 interdisciplinary workpackages that follow a logical progression of scientific themes.