Morphodynamics, subsurface flow and transport

DynaDeep将揭示高能海滩下海洋-陆地相互作用的功能和相关性，在那里，我们建议深层地下作为一个动态的生物反应器和独特的微生物栖息地，影响元素净通量到海洋。为实现这一目标，六个分项目将在联合实地活动、共享取样方法以及实验工作方面进行合作，并以综合方法使用数学模型。分项目P1将研究地下水流动和迁移模式作为水文和地貌动力学的函数。我们假设，国家的最先进的概念，地下水流量和盐度分布在地下河口潮汐影响下不适用于高能量的海滩。相反，我们预期高度瞬态流动条件，盐度、流动方向和停留时间的变化频率和幅度很高。P1将使用相机成像、激光扫描和无人机调查海滩和前滨形态。实地观测将与数值模型相结合，得出典型的适应时间和长度尺度的海滩形态。地球物理方法将能够以快速和非侵入性的方式确定地下盐度模式及其随时间的变化。环境示踪剂数据将用于估计地下停留时间。将利用STE在线观测站的形态、水文（地质）和地球物理数据进行地下水流和运输数值模拟，以全面了解STE内的瞬时水流和运输模式。关于水体分布、流速、停留时间和混合程度的知识将为在子项目P2-P6中进行的地球化学调查提供基础。

DynaDeep will unravel the functionality and relevance of marine-terrestrial interactions below high-energy beaches, where we propose the deep subsurface to act as a dynamic bioreactor and unique microbial habitat affecting elemental net fluxes to the sea. To reach this goal, six subprojects will cooperate in joint field campaigns, shared sampling approaches as well as experimental work and use mathematical models in an integrative approach. Subproject P1 will study groundwater flow and transport patterns as a function of hydro- and morphodynamics. We hypothesize that the state-of-the-art concept of groundwater flow and salinity distribution in subterranean estuaries under tidal influence does not hold for high-energy beaches. Instead, we expect highly transient flow conditions, with high frequencies and amplitudes of change in salinities, flow directions and residence times. P1 will survey beach and foreshore morphology using camera imaging, laser-scanning and drones. Field observations will be combined with numerical models to derive typical adaptation time- and length scales of the beach morphology. Geophysical methods will enable a fast and non-invasive way of identifying subsurface salinity patterns and their change over time. Environmental tracer data will be used to estimate subsurface residence times. Morphological, hydro(geo)logical and geophysical data from the STE Online Observatory will be utilized in numerical groundwater flow and transport modelling to provide a comprehensive picture of transient flow and transport patterns within the STE. This knowledge on the distribution of water bodies, flow velocities, residence times and extent of mixing will provide the basis for biogeochemical investigations carried out in subprojects P2-P6.