Article
Environmental Sciences
Christine Dybwad, Philipp Assmy, Lasse M. Olsen, Ilka Peeken, Anna Nikolopoulos, Thomas Krumpen, Achim Randelhoff, Agnieszka Tatarek, Jozef M. Wiktor, Marit Reigstad
Summary: The study reveals clear seasonal patterns in the development and fate of phytoplankton blooms in the Arctic Ocean's seasonal sea ice zone, with low phytoplankton stocks and carbon fluxes in winter and pre-bloom periods, a short but intense productive season in May and June, and moderate carbon export fluxes in the autumn post-bloom conditions. The taxonomic composition of protist assemblages, large grazers, distance to open water, and Atlantic water advection play crucial roles in determining the fate of the blooms and the magnitude of organic carbon exported out of the surface water column. Intense blooms and high export events were observed in ice-covered waters, challenging previous assumptions about the productivity of the marginal ice zone in the area.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Ecology
Mara Freilich, Alexandre Mignot, Glenn Flierl, Raffaele Ferrari
Summary: Recent observations have shown an increase in phytoplankton biomass in the North Atlantic during winter, attributed to a release from grazing pressure. Mathematical formulations of grazing as a function of phytoplankton concentration that are quadratic or decrease faster than linearly at low concentrations can reproduce the observed fall to spring transition in phytoplankton.
Article
Environmental Sciences
Chi Hung Tang, Edward J. Buskey
Summary: Microzooplankton play a crucial role in connecting primary production and higher trophic levels in marine ecosystems. However, crude oil pollution can disrupt their grazing behavior and the relationship with phytoplankton, potentially leading to phytoplankton blooms.
MARINE POLLUTION BULLETIN
(2022)
Article
Environmental Sciences
Jianwei Wei, Menghua Wang, Karlis Mikelsons, Lide Jiang
Summary: This study explores the variability of chlorophyll-specific absorption coefficient of phytoplankton at 443 nm (aph*(443)) in surface oceans in different seasons and regions. The results show a decreasing gradient of aph*(443) from open oceans to coastal environments, with significant spatial variance. Seasonal variations are prominent and deviate from climatological means. A sinusoidal model characterizes the annual and semiannual features, with latitudinal dependence in amplitudes and phases. Satellite observations confirm a global mean relationship between aph*(443) and Chl-a comparable to in situ measurements, but the seasonal/regional relationships can deviate significantly. The proposed model predicts aph*(443) as a function of geolocation and time, which is validated as a promising alternative to traditional approaches.
Article
Environmental Sciences
Haakon Hop, Anette Wold, Amelie Meyer, Allison Bailey, Maja Hatlebakk, Slawomir Kwasniewski, Peter Leopold, Piotr Kuklinski, Janne E. Soreide
Summary: The impact of the rapidly changing Arctic on zooplankton community structure and seasonal behavior is not yet understood. Zooplankton in the Arctic region is more dependent on surrounding water mass characteristics, such as salinity and depth, rather than geographical location. Seasonal changes in the community are closely linked to algal food availability and seasonal changes from winter to spring.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Lucie Bourreau, Etienne Pauthenet, Loic Le Ster, Baptiste Picard, Esther Portela, Jean-Baptiste Sallee, Clive R. McMahon, Robert Harcourt, Mark Hindell, Christophe Guinet, Sophie Bestley, Jean-Benoit Charrassin, Alice DuVivier, Zephyr Sylvester, Kristen Krumhardt, Stephanie Jenouvrier, Sara Labrousse
Summary: This study investigates the in situ chlorophyll fluorescence signal in Antarctic coastal polynyas during winter and identifies its main oceanographic drivers. The results show a significant fluorescence signal from February to April, with an additional signal in certain locations in August. The fluorescence signal was found to be associated with changes in water depth, mixed layer depth, water temperature, and salinity.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Ji-Hoon Oh, Kyung Min Noh, Hyung-Gyu Lim, Emilia Kyung Jin, Sang-Yoon Jun, Jong-Seong Kug
Summary: This study examines the impacts of Antarctic meltwater on surface phytoplankton biomass in the Southern Ocean. It finds that the enhanced stratification due to the meltwater leads to changes in surface nutrient concentrations, particularly a decrease in nitrate concentration and an increase in dissolved iron concentration. These changes can shift the nutrient availability in the ocean and impact the biomass of phytoplankton.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Biodiversity Conservation
Allison R. Hrycik, Peter D. F. Isles, Rita Adrian, Matthew Albright, Linda C. Bacon, Stella A. Berger, Ruchi Bhattacharya, Hans-Peter Grossart, Josef Hejzlar, Amy Lee Hetherington, Lesley B. Knoll, Alo Laas, Cory P. McDonald, Kellie Merrell, Jens C. Nejstgaard, Kirsten Nelson, Peeter Noges, Andrew M. Paterson, Rachel M. Pilla, Dale M. Robertson, Lars G. Rudstam, James A. Rusak, Steven Sadro, Eugene A. Silow, Jason D. Stockwell, Huaxia Yao, Kiyoko Yokota, Donald C. Pierson
Summary: The study reveals that changes in winter conditions can have significant impacts on summer phytoplankton biomass and production in lakes, with earlier snowmelt in the watershed leading to lower summer chlorophyll-a concentrations. The results suggest a strong negative correlation between runoff timing and summer chlorophyll-a concentrations.
GLOBAL CHANGE BIOLOGY
(2021)
Review
Oceanography
Dong Yan, Jun Nishioka, Takenobu Toyota, Koji Suzuki
Summary: The Sea of Okhotsk plays a key role in the seawater circulation of the North Pacific Ocean. During winter, sea ice forms in the northern shelf and is transported to the southern part of the sea by the East Sakhalin Current. Diatoms are the dominant microalgae in the sea ice ecosystem, with Thalassiosira spp., Porosira glacialis, and Fragilariopsis cylindrus being the major species. The presence of the East Sakhalin Current influences the composition and abundance of microalgae in the seawater stations, with higher concentrations of dissolved Fe and ammonia. The study suggests that the winter phytoplanktonic communities in the southern Sea of Okhotsk are largely dependent on the presence of the East Sakhalin Current.
PROGRESS IN OCEANOGRAPHY
(2022)
Article
Biodiversity Conservation
Takuhei Shiozaki, Amane Fujiwara, Koji Sugie, Shigeto Nishino, Akiko Makabe, Naomi Harada
Summary: This study reveals that diatom blooms can occur near the seafloor rather than at the surface in the shallow Arctic shelf region. The increase in phytoplankton production in the Arctic Ocean due to sea ice loss is often underestimated by satellite observations, as they fail to account for the bottom-associated blooms that occur occasionally. The results highlight the importance of considering these hidden blooms in assessing primary production in the Arctic Ocean.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Tatenda Dalu, Ross N. Cuthbert, Ryan J. Wasserman
Summary: This study assessed plankton diversity patterns in three temporary wetland systems during winter inundation periods. The results showed that plankton community structure did not significantly differ over time or among wetlands, and hydroperiod phases did not have any significant influence on plankton taxa richness. The study highlights the seasonally distinct community succession dynamics in temporary wetlands characterized by both summer and winter inundation events.
CHEMISTRY AND ECOLOGY
(2022)
Review
Oceanography
Jan-Erik Tesdal, Hugh W. Ducklow, Joaquim I. Goes, Igor Yashayaev
Summary: The Labrador Sea is becoming more productive with more intense and widespread phytoplankton blooms. Nutrient concentrations in the upper Labrador Sea are positively correlated with chlorophyll-a concentrations and strongly correlated with winter convection depth.
PROGRESS IN OCEANOGRAPHY
(2022)
Article
Marine & Freshwater Biology
J. Wu, J. N. Negishi, H. Izumi, T. Kanbe, H. Mizumoto, H. Araki
Summary: Freshwater mussels play crucial ecological roles but are endangered due to extirpation and reproductive failure. In this study, a species-specific eDNA assay was developed to monitor the abundance and winter reproduction of Buldowskia iwakawai. The correlation between eDNA concentration and mussel abundance was observed, and the eDNA concentration differed between gravid and non-gravid mussels. However, the increase in eDNA concentration was not detected during the glochidia release period.
Article
Limnology
Andreas Neumann, Justus E. E. van Beusekom, Annika Eisele, Kay-Christian Emeis, Jana Friedrich, Ingrid Kroencke, Ella Lu Logemann, Julia Meyer, Celine Naderipour, Ulrike Schueckel, Alexa Wrede, Michael L. Zettler
Summary: The research indicates that in the German Bight, pore-water advection and macrofaunal activity contribute equally to benthic oxygen uptake, and are influenced by factors such as physical parameters and biotransport.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Ecology
Krystyna Kalinowska, Agnieszka Napiorkowska-Krzebietke, El zbieta Bogacka-Kapusta, Konrad Stawecki, Dariusz Ulikowski
Summary: Winter conditions in lakes of temperate climatic zones are influenced by climate changes. This study tracked the dynamics of abiotic and biotic parameters in three eutrophic lakes during two consecutive winters and found that the phytoplankton and zooplankton communities changed from one winter to the next despite similar environmental conditions.
ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY
(2023)