TY  - JOUR
A1  - Foster, William J.
A1  - Garvie, Christopher L.
A1  - Weiss, Anna M.
A1  - Muscente, A. Drew
A1  - Aberhan, Martin
A1  - Counts, John W.
A1  - Martindale, Rowan C.
T1  - Resilience of marine invertebrate communities during the early Cenozoic hyperthermals
JF  - Scientific Reports
N2  - The hyperthermal events of the Cenozoic, including the Paleocene-Eocene Thermal Maximum, provide an opportunity to investigate the potential effects of climate warming on marine ecosystems. Here, we examine the shallow benthic marine communities preserved in the late Cretaceous to Eocene strata on the Gulf Coastal Plain (United States). In stark contrast to the ecological shifts following the end-Cretaceous mass extinction, our data show that the early Cenozoic hyperthermals did not have a long-term impact on the generic diversity nor composition of the Gulf Coastal Plain molluscan communities. We propose that these communities were resilient to climate change because molluscs are better adapted to high temperatures than other taxa, as demonstrated by their physiology and evolutionary history. In terms of resilience, these communities differ from other shallow-water carbonate ecosystems, such as reef communities, which record significant changes during the early Cenozoic hyperthermals. These data highlight the strikingly different responses of community types, i.e., the almost imperceptible response of molluscs versus the marked turnover of foraminifera and reef faunas. The impact on molluscan communities may have been low because detrimental conditions did not devastate the entire Gulf Coastal Plain, allowing molluscs to rapidly recolonise vacated areas once harsh environmental conditions ameliorated.
KW  - eocene thermal maximum
KW  - gulf coastal plain
KW  - climate-change
KW  - ocean acidification
KW  - extinction event
KW  - carbon-cycle
KW  - heat-stress
KW  - origination
KW  - ecosystems
KW  - diversity
Y1  - 2020
U6  - https://doi.org/10.1038/s41598-020-58986-5
SN  - 2045-2322
VL  - 10
IS  - 1
SP  - 1
EP  - 11
PB  - Springer Nature
CY  - London
ER  - 
TY  - JOUR
A1  - Engel, Anja
A1  - Piontek, Judith
A1  - Grossart, Hans-Peter
A1  - Riebesell, Ulf
A1  - Schulz, Kai Georg
A1  - Sperling, Martin
T1  - Impact of CO2 enrichment on organic matter dynamics during nutrient induced coastal phytoplankton blooms
JF  - Journal of plankton research
N2  - A mesocosm experiment was conducted to investigate the impact of rising fCO(2) on the build-up and decline of organic matter during coastal phytoplankton blooms. Five mesocosms (similar to 38 mA(3) each) were deployed in the Baltic Sea during spring (2009) and enriched with CO2 to yield a gradient of 355-862 A mu atm. Mesocosms were nutrient fertilized initially to induce phytoplankton bloom development. Changes in particulate and dissolved organic matter concentrations, including dissolved high-molecular weight (> 1 kDa) combined carbohydrates, dissolved free and combined amino acids as well as transparent exopolymer particles (TEP), were monitored over 21 days together with bacterial abundance, and hydrolytic extracellular enzyme activities. Overall, organic matter followed well-known bloom dynamics in all CO2 treatments alike. At high fCO(2,) higher Delta POC:Delta PON during bloom rise, and higher TEP concentrations during bloom peak, suggested preferential accumulation of carbon-rich components. TEP concentration at bloom peak was significantly related to subsequent sedimentation of particulate organic matter. Bacterial abundance increased during the bloom and was highest at high fCO(2). We conclude that increasing fCO(2) supports production and exudation of carbon-rich components, enhancing particle aggregation and settling, but also providing substrate and attachment sites for bacteria. More labile organic carbon and higher bacterial abundance can increase rates of oxygen consumption and may intensify the already high risk of oxygen depletion in coastal seas in the future.
KW  - mesocosm
KW  - ocean acidification
KW  - phytoplankton
KW  - organic matter
KW  - TEP
Y1  - 2014
U6  - https://doi.org/10.1093/plankt/fbt125
SN  - 0142-7873
SN  - 1464-3774
VL  - 36
IS  - 3
SP  - 641
EP  - 657
PB  - Oxford Univ. Press
CY  - Oxford
ER  -