Coastal seagrass ecosystems provide important services to nature and mankind in form of coastal protection, nursery grounds and carbon sequestration. However, seagrass meadows are affected by global climate change and anthropogenic stressors. Yet, the mechanistic interactions between these ecosystems and environmental change remain unclear due to the complexity of studying the seagrass habitat, which exhibit a multitude of chemical gradients and dynamics. The requirement for high-resolution measurement techniques for resolving the biogeochemical dynamics and microenvironments surronding seagrasses in their natural habitat has led to the development of a variety of chemical techniques typically quantifying a single analyte at a time, which give limited insight to the true dynamics of the seagrass-sediment interaction which is central for seagrass fitness and survival under environmental change. The NISYEBIO project will develop new multi-parameter chemical imaging techniques by combining luminescence-based optical sensor foils (planar optodes) with diffusional equilibrium in thin-film (DET) enabling simultaneous sensing of pO2, iron, phosphate, nitrite/nitrate, ammonium, manganese, pCO2 and pH. The novel technology will investigate the dynamic chemical microenvironment in the seagrass rhizosphere and how this is modulated by environmental change and plant stress in Zostera marina and Zostera noltei located in different human impacted sites in Cotentin. A pluridisciplinary approach based on biogeochemical total fluxes, ecology and sedimentology will complete these results to better understand two-dimensional mechanisms and seagrass functioning.