Phytoplankton community structure in relation to vertical stratification along a north-south gradient in the Northeast Atlantic Ocean

Abstract. The stratification of the upper oligotrophic ocean has a direct impact on biogeochemistry by regulating the components of the upper-ocean environment that are critical to biological productivity, such as light availability for photosynthesis and nutrient supply from the deep ocean. We investigated the spatial distribution pattern and diversity of phytoplankton communities in the western Pacific Ocean (WPO) in the autumn of 2016, 2017, and 2018. Our results showed the phytoplankton community structure mainly consisted of cyanobacteria, diatoms, and dinoflagellates, while the abundance of Chrysophyceae was negligible. Phytoplankton abundance was high from the equatorial region to 10∘ N and decreased with increasing latitude in spatial distribution. Phytoplankton also showed a strong variation in the vertical distribution. The potential influences of physicochemical parameters on phytoplankton abundance were analyzed by a structural equation model (SEM) to determine nutrient ratios driven by vertical stratification to regulate phytoplankton community structure in the typical oligotrophic ocean. Regions with strong vertical stratification were more favorable for cyanobacteria, whereas weak vertical stratification was more conducive to diatoms and dinoflagellates. Our study shows that stratification is a major determinant of phytoplankton community structure and highlights that physical processes in the ocean control phytoplankton community structure by driving the balance of chemical elements, providing a database to better predict models of changes in phytoplankton community structure under future ocean scenarios.

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Integrating ecophysiology and plankton dynamics into projected maximum fisheries catch potential under climate change in the Northeast Atlantic

ICES Journal of Marine Science ◽

10.1093/icesjms/fsr012 ◽

2011 ◽

Vol 68 (6) ◽

pp. 1008-1018 ◽

Cited By ~ 176

Author(s):

William W. L. Cheung ◽

John Dunne ◽

Jorge L. Sarmiento ◽

Daniel Pauly

Keyword(s):

Climate Change ◽

Community Structure ◽

Phytoplankton Community ◽

Average Rate ◽

Demersal Fish ◽

Range Shift ◽

Geophysical Fluid Dynamics Laboratory ◽

Phytoplankton Community Structure ◽

Plankton Dynamics ◽

Northeast Atlantic

Abstract Cheung, W. W. L., Dunne, J., Sarmiento, J. L., and Pauly, D. 2011. Integrating ecophysiology and plankton dynamics into projected maximum fisheries catch potential under climate change in the Northeast Atlantic. – ICES Journal of Marine Science, 68: 1008–1018. Previous global analyses projected shifts in species distributions and maximum fisheries catch potential across ocean basins by 2050 under the Special Report on Emission Scenarios (SRES) A1B. However, these studies did not account for the effects of changes in ocean biogeochemistry and phytoplankton community structure that affect fish and invertebrate distribution and productivity. This paper uses a dynamic bioclimatic envelope model that incorporates these factors to project distribution and maximum catch potential of 120 species of exploited demersal fish and invertebrates in the Northeast Atlantic. Using projections from the US National Oceanic and Atmospheric Administration's (NOAA) Geophysical Fluid Dynamics Laboratory Earth System Model (ESM2.1) under the SRES A1B, we project an average rate of distribution-centroid shift of 52 km decade−1 northwards and 5.1 m decade−1 deeper from 2005 to 2050. Ocean acidification and reduction in oxygen content reduce growth performance, increase the rate of range shift, and lower the estimated catch potentials (10-year average of 2050 relative to 2005) by 20–30% relative to simulations without considering these factors. Consideration of phytoplankton community structure may further reduce projected catch potentials by ∼10%. These results highlight the sensitivity of marine ecosystems to biogeochemical changes and the need to incorporate likely hypotheses of their biological and ecological effects in assessing climate change impacts.

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Vertical stratification driven nutrient ratios to regulate phytoplankton community structure in the oligotrophic western Pacific Ocean

10.5194/os-2021-67 ◽

2021 ◽

Author(s):

Zhuo Chen ◽

Jun Sun ◽

Ting Gu ◽

Guicheng Zhang ◽

Yuqiu Wei

Keyword(s):

Community Structure ◽

Pacific Ocean ◽

Vertical Distribution ◽

Phytoplankton Community ◽

Western Pacific ◽

Vertical Stratification ◽

Western Pacific Ocean ◽

Phytoplankton Community Structure ◽

Phytoplankton Abundance ◽

The Vertical Distribution

Abstract. Vertical stratification determined the variability of temperature and nutrient distribution in upper seawater, thereby affecting the primary production of the ocean. Nutrients in the oligo-trophic region vary in time and space, and thus phytoplankton vary in their vertical distribution. However, the differences in the vertical distribution of phytoplankton have not been systematically studied. This study investigated the spatial distribution pattern and diversity of phytoplankton communities in the western Pacific Ocean (WPO) in the autumn of 2016, 2017 and 2018, as well as the local hydrological and nutritional status. The Utermöhl method was used to analyze the relevant ecological characteristics of phytoplankton in the surveyed sea area. In the three cruises investigated, we show universal relationships between phytoplankton and (1) vertical stratification, (2) N : P ratio (3) temperature and salinity. The potential influencing factors of physical and chemical parameters on phytoplankton abundance were analyzed by structural equation model (SEM), determining the vertical stratification index was the most important influence factor affecting phytoplankton abundance and indirectly on phytoplankton abundance by dissolved inorganic nitrogen (DIN) and Dissolved inorganic phosphorus (DIP). Vertical stratification determines the vertical distribution of the phytoplankton community structure in the WPO. The areas with strong vertical stratification (Group A and B) are more conducive to the growth of cyanobacteria, and the areas with weak vertical stratification (Group C and D) are more conducive to the bloom of diatoms and dinoflagellates.

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Microbial Functioning and Community Structure Variability in the Mesopelagic and Epipelagic Waters of the Subtropical Northeast Atlantic Ocean

Applied and Environmental Microbiology ◽

10.1128/aem.07962-11 ◽

2012 ◽

Vol 78 (9) ◽

pp. 3309-3316 ◽

Cited By ~ 13

Author(s):

Federico Baltar ◽

Javier Arístegui ◽

Josep M. Gasol ◽

Gerhard J. Herndl

Keyword(s):

Community Structure ◽

Nucleic Acid ◽

Atlantic Ocean ◽

Acid Content ◽

Regional Distribution ◽

Nucleic Acid Content ◽

Leucine Incorporation ◽

Northeast Atlantic ◽

Wide Range ◽

Northeast Atlantic Ocean

ABSTRACTWe analyzed the regional distribution of bulk heterotrophic prokaryotic activity (leucine incorporation) and selected single-cell parameters (cell viability and nucleic acid content) as parameters for microbial functioning, as well as bacterial and archaeal community structure in the epipelagic (0 to 200 m) and mesopelagic (200 to 1,000 m) subtropical Northeast Atlantic Ocean. We selectively sampled three contrasting regions covering a wide range of surface productivity and oceanographic properties within the same basin: (i) the eddy field south of the Canary Islands, (ii) the open-ocean NE Atlantic Subtropical Gyre, and (iii) the upwelling filament off Cape Blanc. In the epipelagic waters, a high regional variation in hydrographic parameters and bacterial community structure was detected, accompanied, however, by a low variability in microbial functioning. In contrast, mesopelagic microbial functioning was highly variable between the studied regions despite the homogeneous abiotic conditions found therein. More microbial functioning parameters indicated differences among the three regions within the mesopelagic (i.e., viability of cells, nucleic acid content, cell-specific heterotrophic activity, nanoflagellate abundance, prokaryote-to-nanoflagellate abundance ratio) than within the epipelagic (i.e., bulk activity, nucleic acid content, and nanoflagellate abundance) waters. Our results show that the mesopelagic realm in the Northeast Atlantic is, in terms of microbial activity, more heterogeneous than its epipelagic counterpart, probably linked to mesoscale hydrographical variations.

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Seasonal changes in phytoplankton community structure in a bioluminescent lagoon, St. Croix, US Virgin Islands

Aquatic Microbial Ecology ◽

10.3354/ame01865 ◽

2018 ◽

Vol 81 (2) ◽

pp. 109-124 ◽

Cited By ~ 2

Author(s):

JL Pinckney ◽

C Tomas ◽

DI Greenfield ◽

K Reale-Munroe ◽

B Castillo ◽

...

Keyword(s):

Community Structure ◽

Seasonal Changes ◽

Phytoplankton Community ◽

Virgin Islands ◽

Phytoplankton Community Structure ◽

Us Virgin Islands

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Seasonal and interannual variability of phytoplankton community structure in a Mediterranean coastal site

Marine Ecology Progress Series ◽

10.3354/meps12493 ◽

2018 ◽

Vol 592 ◽

pp. 57-75 ◽

Cited By ~ 12

Author(s):

S Nunes ◽

M Latasa ◽

JM Gasol ◽

M Estrada

Keyword(s):

Community Structure ◽

Interannual Variability ◽

Phytoplankton Community ◽

Phytoplankton Community Structure ◽

Coastal Site ◽

Seasonal And Interannual Variability

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Response of ocean phytoplankton community structure to climate change over the 21st century: partitioning the effects of nutrients, temperature and light

Biogeosciences ◽

10.5194/bg-7-3941-2010 ◽

2010 ◽

Vol 7 (12) ◽

pp. 3941-3959 ◽

Cited By ~ 96

Author(s):

I. Marinov ◽

S. C. Doney ◽

I. D. Lima

Keyword(s):

Climate Change ◽

Community Structure ◽

Sea Ice ◽

Phytoplankton Biomass ◽

Phytoplankton Community ◽

Vertical Mixing ◽

Phytoplankton Community Structure ◽

Marginal Sea ◽

Small Phytoplankton ◽

The Impact

Abstract. The response of ocean phytoplankton community structure to climate change depends, among other factors, upon species competition for nutrients and light, as well as the increase in surface ocean temperature. We propose an analytical framework linking changes in nutrients, temperature and light with changes in phytoplankton growth rates, and we assess our theoretical considerations against model projections (1980–2100) from a global Earth System model. Our proposed "critical nutrient hypothesis" stipulates the existence of a critical nutrient threshold below (above) which a nutrient change will affect small phytoplankton biomass more (less) than diatom biomass, i.e. the phytoplankton with lower half-saturation coefficient K are influenced more strongly in low nutrient environments. This nutrient threshold broadly corresponds to 45° S and 45° N, poleward of which high vertical mixing and inefficient biology maintain higher surface nutrient concentrations and equatorward of which reduced vertical mixing and more efficient biology maintain lower surface nutrients. In the 45° S–45° N low nutrient region, decreases in limiting nutrients – associated with increased stratification under climate change – are predicted analytically to decrease more strongly the specific growth of small phytoplankton than the growth of diatoms. In high latitudes, the impact of nutrient decrease on phytoplankton biomass is more significant for diatoms than small phytoplankton, and contributes to diatom declines in the northern marginal sea ice and subpolar biomes. In the context of our model, climate driven increases in surface temperature and changes in light are predicted to have a stronger impact on small phytoplankton than on diatom biomass in all ocean domains. Our analytical predictions explain reasonably well the shifts in community structure under a modeled climate-warming scenario. Climate driven changes in nutrients, temperature and light have regionally varying and sometimes counterbalancing impacts on phytoplankton biomass and structure, with nutrients and temperature dominant in the 45° S–45° N band and light-temperature effects dominant in the marginal sea-ice and subpolar regions. As predicted, decreases in nutrients inside the 45° S–45° N "critical nutrient" band result in diatom biomass decreasing more than small phytoplankton biomass. Further stratification from global warming could result in geographical shifts in the "critical nutrient" threshold and additional changes in ecology.

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