Article
Ecology
Benjamin Pontiller, Sandra Martinez-Garcia, Vanessa Joglar, Dennis Amnebrink, Clara Perez-Martinez, Jose M. Gonzalez, Daniel Lundin, Emilio Fernandez, Eva Teira, Jarone Pinhassi
Summary: Coastal upwelling zones are important areas of oceanic productivity. Bacteria play a vital role in the remineralization of dissolved organic matter (DOM) produced by phytoplankton, but the molecular processes involved in the regulation of phytoplankton-derived DOM turnover by bacterial taxa are not well understood. This study used metatranscriptome analysis to compare the gene expression of bacterioplankton in the Northwest Iberian upwelling system. The results showed that different bacterial taxa had specific transcriptional responses during different phases of phytoplankton bloom development, decay, and senescence. The study also highlighted the importance of gene systems involved in the degradation and uptake of carbohydrates and nitrogen-rich compounds in shaping the fate of organic matter in these upwelling-driven ecosystems.
Article
Biochemistry & Molecular Biology
Fiona Chong, Matthew Spencer, Nikolai Maximenko, Jan Hafner, Andrew C. McWhirter, Rebecca R. Helm
Summary: Floating life is a key part of the ocean surface food web, and it is predominantly found in the Sargasso Sea. This study tested the hypothesis that floating life is also concentrated in other gyres with converging surface currents by collecting samples from the North Pacific Garbage Patch. The researchers found higher densities of floating life within the central area of the garbage patch, and a positive relationship between neuston abundance and plastic abundance for certain taxa. This has implications for understanding the ecology of subtropical oceanic gyre ecosystems.
Article
Environmental Sciences
Francois Carlotti, Olivia Gerigny, Dorian Bienvenu, Christophe Ravel, Pamela Fierro-Gonzalez, Loic Guilloux, Nouha Makhlouf, Javier Tesan Onrubia, Marc Pagano
Summary: The aim of this study was to characterize and quantify microplastics at the chlorophyll maximum layer in the western Mediterranean Sea. The study found a high density of fibers in this layer, mainly associated with aggregates, suggesting the importance of marine snow and vertical layering in future microplastic distribution modeling efforts.
MARINE POLLUTION BULLETIN
(2023)
Article
Oceanography
Nikolaos Kokkos, Anastasia Papadopoulou, Konstantinos Zachopoulos, Maria Zoidou, Laurent Beguery, Felix Margirier, Georgios Sylaios
Summary: This study focuses on the dynamics of the deep chlorophyll maximum (DCM) in the North Aegean Sea. By analyzing data on water temperature, conductivity, salinity, chlorophyll-a, CDOM, dissolved oxygen, and particle backscatter collected during a glider mission, a conceptual model on the response of the DCM to water column stratification/mixing was proposed.
CONTINENTAL SHELF RESEARCH
(2023)
Article
Environmental Sciences
Aneesh Anandrao Lotliker, Sanjiba Kumar Baliarsingh, R. Venkat Shesu, Alakes Samanta, R. Chandrasekhar Naik, T. M. Balakrishnan Nair
Summary: This study investigates changes in water quality parameters in the coastal waters off major Indian cities and river basins during lockdown periods, finding a significant decrease in parameter magnitudes, with the coastal waters of the western Bay of Bengal experiencing the most significant reduction.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Sonja M. van Leeuwen, Hermann-J. Lenhart, Theo C. Prins, Anouk Blauw, Xavier Desmit, Liam Fernand, Rene Friedland, Onur Kerimoglu, Genevieve Lacroix, Annelotte van der Linden, Alain Lefebvre, Johan van der Molen, Martin Plus, Itzel Ruvalcaba Baroni, Tiago Silva, Christoph Stegert, Tineke A. Troost, Lauriane Vilmin
Summary: Using a model assessment, we estimated the pre-eutrophic state of North-East Atlantic marine waters, providing accurate estimates for key eutrophication indicators. The results showed lower nutrient concentrations and nitrogen to phosphorus ratios in coastal areas under pre-eutrophic conditions compared to the current state. These findings open the possibility for establishing reference values for eutrophication indicators in marine regions.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Siyu Meng, Xun Gong, Yang Yu, Xiaohong Yao, Xiang Gong, Keyu Lu, Chao Zhang, Jie Shi, Xiaojie Yu, Huiwang Gao
Summary: The study found that the North Pacific ocean desert has experienced oligotrophication and expansion over the past 20 years, which is related to warming upper oceans in most regions, but the Chl-a variations in the southwest area are linked to regional changes in sea surface heights. Additionally, the insignificant shift in the mean position of NPOD is likely controlled by the Pacific decadal oscillation processes.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Qian Liu, Laura F. Robinson, Erica Hendy, Maria G. Prokopenko, Timothy D. J. Knowles, Tao Li, Ana Samperiz
Summary: Deep-sea bamboo corals have been used as archives for reconstructing past ocean changes, but the interpretation of geochemical signals recorded in their organic nodes, particularly regarding water depth, remains uncertain. Through isotopic analysis of bamboo corals collected from the central and eastern tropical Atlantic, contrasting results were found between the two regions. The carbon source for bamboo coral organic nodes may not always reside in the mixed layer, especially in oligotrophic regions, which has implications for age model development.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Environmental Sciences
Aida Alvera-Azcarate, Dimitry Van der Zande, Alexander Barth, Charles Troupin, Samuel Martin, Jean-Marie Beckers
Summary: This study examines the changes in chlorophyll and suspended particulate matter in the North Sea from 1998 to 2020 using satellite data. The results show an earlier and longer duration of the spring bloom each year, but no clear trend in CHL values. The influence of rising water temperature on the timing of the spring bloom appears to be dominant, with sea surface temperature having a greater impact on bloom timing than SPM concentration.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Christoph Stegert, Hermann-Josef Lenhart, Anouk Blauw, Rene Friedland, Wera Leujak, Onur Kerimoglu
Summary: This study systematically quantifies various sources of uncertainties and assesses their importance for the eutrophication issues in the North Sea. Utilizing two coupled physical-biogeochemical model systems, the study evaluates the simulation results of the historical state and reveals differences in confidence levels of the model results.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Geography, Physical
S. Ni, Z. Lu, Q. Zhang, J. Groeneveld, K. L. Knudsen, M. -S. Seidenkrantz, H. L. Filipsson
Summary: This study investigates the effects of solar radiation and greenhouse gas forcing on the hydrography and water-mass exchange in the North Sea and Baltic Sea region during the Last Interglacial (LIG) period. The results show that the Baltic Sea region had more saline and colder bottom waters during the LIG, attributed to lower greenhouse gas levels and enhanced water exchange. The study also reveals a stronger thermocline and higher sea surface temperature during the LIG, with significant correlations between salinity anomalies and the North Atlantic Oscillation (NAO) index.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Marine & Freshwater Biology
Fabio Ricci, Samuela Capellacci, Alessandra Campanelli, Federica Grilli, Mauro Marini, Antonella Penna
Summary: This study analyzed the dynamics of physical and biogeochemical properties in a temperate coastal area in the north-western Adriatic Sea. The results showed that the inputs from minor rivers and ecological processes played a role in the interannual and seasonal biogeochemical dynamics. The study also found a trend towards more oligotrophic conditions, mainly due to reduced phosphate and nitrate loadings from the minor rivers and increased freshwater discharges.
ESTUARINE COASTAL AND SHELF SCIENCE
(2022)
Article
Multidisciplinary Sciences
Li Liu, Mingming Chen, Xianhui S. Wan, Chuanjun Du, Zhiyu Liu, Zhendong Hu, Zong-Pei Jiang, Kuanbo Zhou, Hongyang Lin, Hui Shen, Duo Zhao, Lanying Yuan, Lei Hou, Jin-Yu T. Yang, Xiaolin Li, Shuh-Ji Kao, Emily J. Zakem, Wei Qin, Minhan Dai, Yao Zhang
Summary: This study found that cyclonic eddies in the western North Pacific subtropical gyre enhance nitrite oxidation and reduce nitrite concentrations in the primary nitrite maximum. The results demonstrate a spatial decoupling of the two steps of nitrification in response to mesoscale processes.
Article
Meteorology & Atmospheric Sciences
Guwei Zhang, Gang Zeng, Xiaoye Yang, Vedaste Iyakaremye
Summary: Heatwaves in North China can be categorized into two types based on spatial intensity - the S-type with a center in the south and the N-type with a center in the north. Observational analysis suggests a connection between changes in sea ice concentration in the Barents-Kara Sea and these two types of heatwaves. Decreased sea ice concentration leads to a northward shift in the heatwave center, increased rainfall, and weakened heatwave intensity, resulting in the N-type heatwave. Conversely, increased sea ice concentration leads to a southward shift in the heatwave center and strengthened heatwave intensity, resulting in the S-type heatwave.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2022)
Article
Ecology
Teng Wang, Haofei Zhang, Lei Gao, Lixin Zhu
Summary: The influence of tropical cyclones (TCs) on the low-latitude (LLZ) and middle-latitude zones (MLZ) in the western North Pacific (WNP) varies due to differences in upper ocean conditions. Although TCs in the MLZ have lower intensity and transit time compared to the LLZ, they result in greater deepening of the mixed-layer depth (MLD), more significant cooling of sea surface temperature (SST), and a more pronounced increase in surface chlorophyll-a (Chl-a) concentration. These differences are directly related to the variations in upper ocean physical and biochemical structure between the two regions.
REGIONAL STUDIES IN MARINE SCIENCE
(2022)
Article
Ecology
Robert Fischer, Helge-Ansgar Giebel, Helmut Hillebrand, Robert Ptacnik
Article
Microbiology
Franziska Klotz, Thorsten Brinkhoff, Heike M. Freese, Matthias Wietz, Andreas Teske, Meinhard Simon, Helge-Ansgar Giebel
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY
(2018)
Article
Microbiology
Insa Bakenhus, Leon Dlugosch, Helge-Ansgar Giebel, Christine Beardsley, Meinhard Simon, Matthias Wietz
ENVIRONMENTAL MICROBIOLOGY
(2018)
Article
Microbiology
Helge-Ansgar Giebel, Mathias Wolterink, Thorsten Brinkhoff, Meinhard Simon
FEMS MICROBIOLOGY ECOLOGY
(2019)
Article
Biotechnology & Applied Microbiology
Insa Bakenhus, Bernd Wemheuer, Pinar Akyol, Helge-Ansgar Giebel, Leon Dlugosch, Rolf Daniel, Meinhard Simon
SYSTEMATIC AND APPLIED MICROBIOLOGY
(2019)
Article
Environmental Sciences
Tiera-Brandy Robinson, Helge-Ansgar Giebel, Oliver Wurl
Article
Chemistry, Multidisciplinary
Christian T. Hansen, Jutta Niggemann, Helge-Ansgar Giebel, Meinhard Simon, Wolfgang Bach, Thorsten Dittmar
Article
Spectroscopy
Mario L. Miranda, H. Osterholz, H. -A. Giebel, P. Bruhnke, T. Dittmar, O. Zielinski
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2020)
Article
Microbiology
Janina Rahlff, Christian Stolle, Helge-Ansgar Giebel, Nur Ili Hamizah Mustaffa, Oliver Wurl, Daniel P. R. Herlemann
Summary: The study found that marine foams have a high abundance of phototrophic and prokaryotic cells, as well as a high concentration of surface-active substances. The bacterial communities in foams differ significantly from the sea-surface microlayer and underlying water, characterized by a high abundance of Gammaproteobacteria. Despite differences in overall bacterial composition, the presence of SML bacteria in foams suggests that foams are strongly influenced by the SML.
FEMS MICROBIOLOGY ECOLOGY
(2021)
Article
Plant Sciences
Tran Quoc Den, Thomas R. Neu, Sabiha Sultana, Helge-A. Giebel, Meinhard Simon, Sara Billerbeck
Summary: Interactions between marine diatoms and bacteria were investigated using scanning electron microscopy and confocal laser scanning microscopy. A new isolate of Thalassiosira rotula was characterized, and fluorescently labeled lectins were used to stain specific glycoconjugates. Different interactions with bacteria were observed in axenic cultures and consortia. Fucose-containing threads were found to be the dominant glycoconjugates secreted by T. rotula, and bacteria attached mainly to these glycoconjugates. Colonization patterns differed between single bacteria and bacterial co-cultures, indicating the impact of bacterial interactions on diatom colonization.
JOURNAL OF PHYCOLOGY
(2023)
Article
Multidisciplinary Sciences
Janina Rahlff, Sarah P. Esser, Julia Plewka, Mara Elena Heinrichs, Andre Soares, Claudio Scarchilli, Paolo Grigioni, Heike Wex, Helge-Ansgar Giebel, Alexander J. Probst
Summary: Marine viruses can be dispersed into the atmosphere through the air-sea interface and detected in rainwater. Virus enrichment in the surface microlayer and sea foams, as well as higher G/C base content in viruses from rain and aerosols, were observed. These findings support the transmission of viruses along the water cycle.
NATURE COMMUNICATIONS
(2023)
Article
Ecology
Janina Rahlff, Matthias Wietz, Helge-Ansgar Giebel, Oliver Bayfield, Emelie Nilsson, Kristofer Bergstrom, Kristopher Kieft, Karthik Anantharaman, Mariana Ribas-Ribas, Hannah D. Schweitzer, Oliver Wurl, Matthias Hoetzinger, Alfred Antson, Karin Holmfeldt
Summary: This study characterizes viruses and bacteria in a brackish slick surface microlayer (SML), comparing them to non-slick SML and subsurface water. The slick SML contains higher abundances of virus-like particles, prokaryotic cells, and dissolved organic carbon. The community of viral operational taxonomic units (vOTUs) in slick SML is distinct and shows specific metabolic profiles of bacteria. The study also isolates previously unknown lytic phages that contribute to biogeochemical cycling in coastal ecosystems.
ISME COMMUNICATIONS
(2023)
Article
Environmental Sciences
Janina Rahlff, Christian Stolle, Helge-Ansgar Giebel, Mariana Ribas-Ribas, Lars Riis Damgaard, Oliver Wurl
FRONTIERS IN MARINE SCIENCE
(2019)
Article
Microbiology
Bernd Wemheuer, Franziska Wemheuer, Dimitri Meier, Sara Billerbeck, Helge-Ansgar Giebel, Meinhard Simon, Christoph Scherber, Rolf Daniel
Article
Microbiology
Janina Rahlff, Christian Stolle, Helge-Ansgar Giebel, Thorsten Brinkhoff, Mariana Ribas-Ribas, Dorothee Hodapp, Oliver Wurl
FEMS MICROBIOLOGY ECOLOGY
(2017)