Phytoplankton community disruption caused by latest Cretaceous global warming

Abstract. Phytoplankton responses to a ~ 350 kiloyear long phase of gradual late Maastrichtian (latest-Cretaceous) global warming starting at ~ 66.4 Ma can provide valuable insights into the long-term influences of global change on marine ecosystems. Here we perform micropaleontological analyses on three cores from the New Jersey paleoshelf, to assess the response of phytoplankton using cyst-forming dinoflagellates and benthic ecosystems using benthic foraminifera. Our records show that this Latest Maastrichtian Warming Event (LMWE), characterized by a 4.0 ± 1.3 ⁰C warming of sea-surface waters on the New Jersey paleoshelf, resulted in a succession of nearly monospecific dinoflagellate cyst assemblages, dominated by the species Palynodinium grallator. This response, likely triggered by the combination of warmer and seasonally thermally-stratified seas, appears to have been more intense at offshore sites than at nearshore sites. The LMWE, and related dinoflagellate response, is associated with an impoverished benthic ecosystem. A wider geographic survey of literature data reveals that the dominance of P. grallator is a marker for the LMWE throughout the northern mid-latitudes. While the dinocyst assemblage returned to a stable, normal marine community in the last tens of thousands of years of the Maastrichtian, benthic foraminiferal diversity remained slightly suppressed. Increased ecosystem stress during the latest Maastrichtian potentially primed global ecosystems for the subsequent mass extinction following the K-Pg boundary Chicxulub impact.

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Phytoplankton community disruption caused by latest Cretaceous global warming

Biogeosciences ◽

10.5194/bg-16-4201-2019 ◽

2019 ◽

Vol 16 (21) ◽

pp. 4201-4210 ◽

Cited By ~ 2

Author(s):

Johan Vellekoop ◽

Lineke Woelders ◽

Appy Sluijs ◽

Kenneth G. Miller ◽

Robert P. Speijer

Keyword(s):

Global Warming ◽

New Jersey ◽

Surface Waters ◽

Mass Extinction ◽

Phytoplankton Community ◽

Sea Surface ◽

Benthic Ecosystems ◽

Chicxulub Impact ◽

Marine Community

Abstract. Phytoplankton responses to a ∼350 kyr (kiloyear) long phase of gradual late Maastrichtian (latest Cretaceous) global warming starting at ∼66.4 Ma can provide valuable insights into the long-term influences of global change on marine ecosystems. Here we perform micropaleontological analyses on three cores from the New Jersey paleoshelf to assess the response of phytoplankton using cyst-forming dinoflagellates and benthic ecosystems using benthic foraminifera. Our records show that this latest Maastrichtian warming event (LMWE), characterized by a 4.0±1.3 ∘C warming of sea surface waters on the New Jersey paleoshelf, resulted in a succession of nearly monospecific dinoflagellate-cyst assemblages, dominated by the species Palynodinium grallator. This response, likely triggered by the combination of warmer and seasonally thermally stratified seas, appears to have been more intense at offshore sites than at nearshore sites. The LMWE, and related dinoflagellate response, is associated with an impoverished benthic ecosystem. A wider geographic survey of literature data reveals that the dominance of P. grallator is a marker for the LMWE throughout the northern midlatitudes. While the dinocyst assemblage returned to a stable, normal marine community in the last tens of thousands of years of the Maastrichtian, benthic foraminiferal diversity appears to have remained slightly suppressed. Increased ecosystem stress during the latest Maastrichtian potentially primed global ecosystems for the subsequent mass extinction following the Cretaceous Paleogene (K–Pg) boundary Chicxulub impact.

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Deep marine anoxia of the southern Panthalassa during the Permian-Triassic – global impacts of the Siberian Traps

10.5194/egusphere-egu21-13733 ◽

2021 ◽

Author(s):

Stephen Grasby ◽

David Bond ◽

Paul Wignall ◽

Runsheng Yin ◽

Lorna Strachan ◽

...

Keyword(s):

Global Warming ◽

Ocean Circulation ◽

Surface Waters ◽

Mass Extinction ◽

Bottom Water ◽

Deep Ocean ◽

Marine Life ◽

Siberian Traps ◽

Southern Latitude ◽

Global Impacts

<p>The deep-water record of marine anoxia across the Permo-Triassic mass extinction (PTME) is highly controversial; both the length of time and severity of anoxic conditions are uncertain. Panthalassa Ocean circulation models show varying results, ranging from a well-ventilated deep ocean to rapidly developing northern, but not southern, latitude anoxia in response to Siberian Traps driven global warming. To address this uncertainty we examined a southern paleo-latitude pelagic record. Trace metal and pyrite framboid data show bottom water euxinc conditions developed in the southern Panthalassa Ocean at the PTME, coincident with enhanced volcanic activity indicated by Hg geochemistry. While a global deep-ocean euxinic event at the PTME placed extraordinary stress on marine life, southern surface waters appear to have recovered more quickly as radiolarian populations return several million years before they do in northern Panthalassa.</p>

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Recent changes (2013-2017) in scyphomedusan fauna in the Boka Kotorska Bay, Montenegro (Southeast Adriatic)

Acta Adriatica ◽

10.32582/aa.60.1.2 ◽

2019 ◽

Vol 60 (1) ◽

pp. 25-39

Author(s):

Ivana Violić ◽

Davor Lučić ◽

Ivona Milić Beran ◽

Vesna Mačić ◽

Branka Pestorić ◽

...

Keyword(s):

Time Series ◽

Global Warming ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Water Column ◽

Sea Surface ◽

Long Term Trends ◽

Sst Anomalies ◽

Chrysaora Hysoscella

A semi- quantitative time series (2013-2017) was used to present the recent events of scyphomedusae appearance and abundance in the Boka Kotorska Bay, Montenegro, Southeast Adriatic. Six meroplanktonic species were recorded: Aurelia spp, Chrysaora hysoscella, Cotylorhiza tuberculata ̧ Discomedusa lobata, Drymonema dalmatinum and Rhizostoma pulmo. Among them, C. hysoscella and D. lobata dominated in the water column during winter and spring, forming dense aggregations in March and May, and February to May, respectively. Our description of the D. lobata blooms are actually the first known records of blooms for this species. C. tuberculata was observed in the Bay principally in August and September. The bloom was occurred only in 2017, being the first information of C. tuberculata mass appearance in this area. We hypothesized that global warming phenomena could trigger the observed changes, and in this respect, long-term trends of sea surface temperature (SST) fluctuations were analysed. The scyphomedusae blooms coincided with high positive SST anomalies, noted in the last seven years for this area. To better understand the mechanisms underlying changes in their phenology and abundance, detailed studies on benthic stages in the Bay are essential.

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Transient Permian-Triassic euxinia in the southern Panthalassa deep ocean

Geology ◽

10.1130/g48928.1 ◽

2021 ◽

Author(s):

S.E. Grasby ◽

D.P.G. Bond ◽

P.B. Wignall ◽

R. Yin ◽

L.J. Strachan ◽

...

Keyword(s):

Global Warming ◽

Ocean Circulation ◽

Surface Waters ◽

Mass Extinction ◽

Bottom Water ◽

Deep Ocean ◽

Global Ocean ◽

Marine Life ◽

Siberian Traps ◽

Southern Latitude

Both the duration and severity of deep-water anoxic conditions across the Permian-Triassic mass extinction (PTME) are controversial. Panthalassa Ocean circulation models yield varying results, ranging from a well-ventilated deep ocean to rapidly developing northern-latitude, but not southern-latitude, anoxia in response to Siberian Traps–driven global warming. To address this uncertainty, we examined a southern-paleolatitude pelagic record. Trace metal and pyrite framboid data suggest bottom-water euxinic conditions developed in the southern Panthalassa Ocean at the PTME, coincident with enhanced volcanic activity indicated by Hg geochemistry. While a global ocean euxinic event at the PTME placed extraordinary stress on marine life, southern surface waters appear to have recovered more quickly as radiolarian populations returned several million years before they did in northern Panthalassa.

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Faunal changes across the Cretaceous-Tertiary (K-T) boundary in the Atlantic Coastal Plain of New Jersey: Restructuring the marine community after the K-T mass-extinction event

Catastrophic events and mass extinctions: impacts and beyond ◽

10.1130/0-8137-2356-6.291 ◽

2002 ◽

Cited By ~ 6

Author(s):

William B. Gallagher

Keyword(s):

New Jersey ◽

Coastal Plain ◽

Mass Extinction ◽

Atlantic Coastal Plain ◽

Extinction Event ◽

Mass Extinction Event ◽

Atlantic Coastal ◽

Marine Community

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Long-term trends of global marine primary and secondary aerosol production during the recent global warming hiatus (2000–2015)

10.5194/acp-2018-322 ◽

2018 ◽

Author(s):

Sang-Keun Song ◽

Zang-Ho Shon ◽

Yu-Na Choi ◽

Young-Baek Son ◽

Minsung Kang ◽

...

Keyword(s):

Global Warming ◽

Pacific Ocean ◽

Southern Ocean ◽

Atmospheric Aerosol ◽

Sea Surface ◽

Aerosol Loading ◽

Global Warming Hiatus ◽

Long Term Trends ◽

Warming Hiatus

Abstract. Long-term trends in global sea spray aerosol (SSA) emissions and dimethyl sulfide (DMS) fluxes from sea to air during the recent global warming hiatus (2000–2015) were analyzed using satellite observations and modelling data. The SSA emissions were estimated using a widely used whitecap method with sea surface temperature (SST) dependence. In addition, sea-to-air DMS fluxes were also used to quantify the secondary contributions of DMS through its sequential oxidation and gas-to-particle conversion. Aerosol optical depth (AOD) was estimated by an aerosol optical model using the number concentration of SSA and non-sea-salt sulfate from DMS. The estimated AOD, which was derived from the SSA and DMS emitted from the sea surface, was compared with satellite-derived AOD to quantify its (primary and secondary) contribution to atmospheric aerosol loading (i.e., observed AOD). Yearly global mean anomalies in DMS fluxes and AOD derived from SSA showed statistically significant downward trends during the recent global warming hiatus, whereas SSA emissions and AOD derived from DMS oxidation did not. In terms of regional trends, the decreases in SSA emissions during 2000–2015 occurred over the central Pacific Ocean, the Indian Ocean, and the Caribbean Sea, whereas upward trends in SSA emissions occurred over the tropical southeastern Pacific Ocean, the Southern Ocean, and the North Atlantic Ocean. DMS fluxes during the study period showed a clear downward trend over most regions of the global ocean. The estimates of the contributions of SSA (primary) and DMS (secondary) to atmospheric aerosol loading were 23–62% and 26–38%, respectively, with the largest primary contribution (~90%) over the Southern Ocean.

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Ecological response to collapse of the biological pump following the mass extinction at the Cretaceous–Paleogene boundary

Biogeosciences ◽

10.5194/bg-14-885-2017 ◽

2017 ◽

Vol 14 (4) ◽

pp. 885-900 ◽

Cited By ~ 15

Author(s):

Johan Vellekoop ◽

Lineke Woelders ◽

Sanem Açikalin ◽

Jan Smit ◽

Bas van de Schootbrugge ◽

...

Keyword(s):

Mass Extinction ◽

Benthic Communities ◽

Ocean Model ◽

Early Paleocene ◽

Post Impact ◽

Impact Phase ◽

Benthic Ecosystems ◽

Planktonic Community ◽

Export Productivity

Abstract. It is commonly accepted that the mass extinction associated with the Cretaceous–Paleogene (K–Pg) boundary (∼ 66 Ma) is related to the environmental effects of a large extraterrestrial impact. The biological and oceanographic consequences of the mass extinction are, however, still poorly understood. According to the Living Ocean model, the biological crisis at the K–Pg boundary resulted in a long-term reduction of export productivity in the early Paleocene. Here, we combine organic-walled dinoflagellate cyst (dinocyst) and benthic foraminiferal analyses to provide new insights into changes in the coupling of pelagic and benthic ecosystems. To this end, we perform dinocyst and benthic foraminiferal analyses on the recently discovered Tethyan K–Pg boundary section at Okçular, Turkey, and compare the results with other K–Pg boundary sites in the Tethys. The post-impact dominance of epibenthic morphotypes and an increase of inferred heterotrophic dinocysts in the early Paleocene at Okçular are consistent with published records from other western Tethyan sites. Together, these records indicate that during the early Paleocene more nutrients remained available for the Tethyan planktonic community, whereas benthic communities were deprived of food. Hence, in the post-impact phase the reduction of export productivity likely resulted in enhanced recycling of nutrients in the upper part of the water column, all along the western Tethyan margins.

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