539e82b5-ce58-4a49-abf5-f858ba29fc34 Monitoring of the northern coast of Portugal 2024-06-01 This research site is located along the northern coast of Portugal and includes 14 sampling stations distributed across four ecosystems. Monitoring activities are conducted on a seasonal basis (starting in summer 2024) across intertidal, subtidal, pelagic, rocky, and sedimentary environments (0-35m depth). The monitoring programme targets multiple biological components, including nekton, zooplankton, phytoplankton, benthos, infauna, megafauna (&gt;20 cm), macrofauna, meiofauna, and microbiota (bacteria, protists, and similarly sized eukaryotes), together with physical, chemical, acoustic, and molecular observations. Sampling methods varied across environments but followed standardized procedures. Plankton was collected using 200 µm mesh nets equipped with flowmeters; fish larvae were sampled with 500 µm plankton nets. Sediment and infauna were obtained using Van Veen grabs and sieved through 1 mm mesh. Intertidal surveys used photo-quadrats (50×50 cm) placed across tidal zones, while subtidal communities were recorded through scuba diving using transects and photo-quadrats. Water samples were taken for nutrients, contaminants, eDNA and microbial analyses, and CTD profiles were performed for physical and chemical variables. Acoustic data were collected using calibrated hydrophones. Samples were processed using standardized laboratory protocols across different components (chemical, microbial, benthic communities, zooplankton/fish larvae, microplastics, etc.). Macrobenthos from sediment grabs was sieved (1 mm), sorted, and taxonomically identified under stereomicroscopes. Zooplankton and ichthyoplankton were preserved and identified using stereomicroscopy. Water samples for nutrients, metals and organic contaminants were filtered, digested when required, and analysed via spectrophotometry or chromatography. Microplastics were pre-treated, filtered, and examined under stereomicroscopy for quantification and classification. eDNA samples were filtered, DNA extracted and prepared for metabarcoding. Acoustic, photographic and video datasets were processed with dedicated software for quality control, annotation, and species identification. Images and video are archived digitally with associated metadata. eDNA samples obtained from filtered water are stored frozen until extraction. Microbial cultures, when applicable, are maintained under controlled laboratory conditions. Benthic samples collected with sediment grabs are frozen prior to processing and retained after identification. Pelagic organisms, including zooplankton and fish larvae, are preserved in ethanol for long-term storage and future analyses. <div><br></div> coastal monitoring eDNA benthos microbiota acoustic monitoring plankton Catarina Magalhães CIIMAR - Interdisciplinary Centre of Marine and Environmental Research CIIMARWATCH@ciimar.up.pt Oscar Babé CIIMAR - Interdisciplinary Centre of Marine and Environmental Research CIIMARWATCH@ciimar.up.pt Northern coast of Portugal -9.50 -8.00 41.19 41.68