http://hdl.handle.net/10174/148 Sat, 04 Apr 2026 00:27:56 GMT 2026-04-04T00:27:56Z http://hdl.handle.net/10174/41020 Title: Fluid Dynamics of the São Jorge Channel, Azores Plateau First results of RV Meteor expedition M186 Authors: Schmidt, C; Zitoun, R.; et al. Abstract: Young oceanic plateaus are important for fluid exchange between the lithosphere and the ocean. Increased heat fluxes can lead to a large-scale upwelling of fluids that play a role in global elemental cycles. In addition, variations in fluid chemistries can potentially influence the biomass and species compositions of microbial and benthic communities in sediments exposed to subsurface fluid flow. Yet, the present understanding of these young oceanic plateaus in terms of their fluid dynamics and their biogeochemical local and global impacts is limited. The goal of RV Meteor Expedition M186 in December 2022 was to investigate how subsurface fluids on the young Azores Plateau, Central North Atlantic, vary with respect to their flow rates, chemical compositions, and the prevalent on microbial and benthic communities at and below the seafloor. First data from the São Jorge Channel (Azores Plateau) show that fluid dynamics here are diffuse rather than focused, and that fluid chemical compositions nonetheless show strong local variations, over a small spatial scale of 65 km2, that could be related to differences in fluid origins and fluid flow paths. However, the connection of fluid conduits, heat flow data and biogeochemical data as well as their relation to faults visible in seismic data are rather complex. Our first results thus indicate that diffuse fluid flow on young oceanic plateaus is highly heterogeneous despite occurring over large sediment-covered areas. Thus, the role of fluids at young oceanic plateaus as an important intermediate between the lithosphere and the ocean cannot be generalized over large spatial and possibly temporal scales. Fri, 31 Mar 2023 23:00:00 GMT http://hdl.handle.net/10174/41020 2023-03-31T23:00:00Z http://hdl.handle.net/10174/40075 Title: Bivalve gut microbiome responses to sediment characteristics and anthropogenic activities in Cerastoderma edule (Linnaeus, 1758) Authors: Neves, Joana; Mil-Homens, Mário; Martins, Marta; Adão, Helena; Arteaga, Jorge Abstract: Estuaries are highly dynamic ecosystems that are influenced by fluctuating environmental conditions and sediment-associated contamination. These factors can significantly affect microbiomes associated with their hosts. In this study, we investigated the gut microbiome of the bivalve Cerastoderma edule by integrating bacteria (16S rRNA) and fungal (ITS) diversity data with sediment physicochemical parameters across three estuarine sites subjected to varying degrees of anthropogenic pressure. Sampling was conducted in the Sado Estuary (Portugal), a warm-temperate, mesotidal system. The selected areas, Tróia (TR), Gâmbia (GAM), and Navigator (NAV), represent contrasting environmental settings, from low-contaminated (TR) to more impacted zones influenced by industrial and aquaculture activities (GAM and NAV). Microbial diversity and composition were assessed on a seasonal basis using next-generation sequencing and multivariate analyses. Alpha diversity metrics revealed differences in bacterial communities between sites and seasons, whereas fungal diversity remained relatively stable across locations. This suggests that gut-associated fungi are more resilient to environmental pressures, although specific compositional shifts were observed in the impacted areas, with some taxa showing correlations with trace metal concentrations. Principal Component Analysis (PCA) indicated strong associations between gut microbial composition and sediment parameters, including organic matter, salinity, and trace metals. In particular, the bacterial communities exhibited strong responses to trace metals, such as Hg, Zn, and Pb. Functional inference (FAPROTAX) highlighted the microbial involvement in nitrogen, sulfur, and carbon cycling, indicating potential adaptive responses to contamination. Together, these findings support the utility of the C. edule gut microbiome as a sensitive indicator of estuarine environmental status and host–environment interactions. Moreover, they underscored the importance of including both bacterial and fungal components to obtain a more holistic understanding of microbiome-mediated ecosystem functions. Wed, 19 Nov 2025 00:00:00 GMT http://hdl.handle.net/10174/40075 2025-11-19T00:00:00Z http://hdl.handle.net/10174/37704 Title: Life Águeda – Restoring River Connectivity For Migratory Fish In The Vouga River Basin Authors: Pedro, S.; Alexandre, CM; Mateus, CS; Quintella, BR; Boavida-Portugal, J; Lança, M.J.; Belo, AF; Pereira, E; Rato, AS; Oliveira, IC; Silva, S; Almeida, P.R. Abstract: Presentation of the results of the work carried out on this subject in the Vouga River basin Sun, 31 Mar 2024 23:00:00 GMT http://hdl.handle.net/10174/37704 2024-03-31T23:00:00Z http://hdl.handle.net/10174/36609 Title: Citizen science results of GTAN-SPEA: censuses of the short-eared owl (Asio flammeus) and barn owl (Tyto alba) and Noctua-Portugal Program Authors: Lourenço, Rui; Roque, Inês; Falé, João; Tomé, Ricardo; GTAN, SPEA Abstract: The Working Group on Nocturnal Birds of SPEA (GTAN-SPEA) promotes since 2010 the monitoring program for nocturnal birds called “Noctua-Portugal”. This citizen-science initiative has allowed population trend estimates to be calculated for the 10 target species. After 13 sampling seasons (2009/10 to 2021/22), the data collected by more than 140 volunteer collaborators in 91 sampling squares points to a strong decline in the Scops Owl (Otus scops) and the Little Owl (Athene noctua), and a moderate decline in Barn Owl (Tyto alba), Long-eared owl (Asio otus) and Eurasian Stone Curlew (Burhinus oedicnemus). On the other hand, the Eagle Owl (Bubo bubo), the Tawny Owl (Strix aluco), and the two nightjars (Caprimulgus europaeus, C. ruficollis) populations seem to be stable. It has not been possible to estimate the population trend for the Short-eared Owl (Asio flammeus) due to the scarcity of data. To overcome this limitation, in the winter of 2021/22, GTAN-SPEA promoted the 1st national census of the wintering population of the Short-eared Owl. Counts were carried out by 178 volunteers in 20 priority areas for the species in mainland Portugal, with the support of regional coordinators. Counts based on 340 listening points and 210 road surveys were carried out over two weekends. During the census, between 91 and 112 Short-eared Owls were counted. Most individuals were detected on the coast, mainly in the Tagus Estuary and Ria de Aveiro. In 2023, GTAN-SPEA promoted the 1st national census of the Barn Owl, thus seeking to better understand the causes behind the declining trend of this nocturnal bird associated with agricultural and urban areas, which often nests in artificial structures. This initiative was open to the entire population, relying on two methodological approaches: a systematic census and a non-systematic census (by completing an online survey). 24 regional coordinators and 268 volunteers participated in the systematic census, who carried out 1129 listening points in mainland Portugal. 340 barn owls were detected, corresponding to a detection frequency of 30%. The detection frequency per district varied between 13% (Castelo Branco) and 61% (Coimbra). In the non-systematic census, 256 surveys and 150 listening points were submitted. In total, 257 barn owls were recorded, 201 in the surveys and 56 in the listening points. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/10174/36609 2023-01-01T00:00:00Z