under review:        Langer G., Nehrke G., Keul N., de Nooijer L., Littmann S., Kuypers M., Bijma J., Mg and Sr banding in the                                                             symbiont-barren  foraminifer Ammonmia aomoriensis as revealed by NanoSIMS analyses

2017                       Keul N., Peijnenburg K.T.C.A, Andersen, N., Kitidis V., Goetze, E., Schneider, R., Pteropods are excellent recorders of                                         surface temperature and carbonate ion concentration (accepted at Scientific Reports)

2017                       Manno C., (et al., inkl. Keul N.), Shelled pteropods in peril: Assessing vulnerability in a high CO2 ocean, Ear.-Sci. Rev.,                                      169: 132-145, doi: 10.1016/j.earscirev.2017.04.005.

2016                       Keul N., Langer G., Thoms S., de Nooijer L. J.,  Reichart G.-J, Bijma J., Exploring foraminiferal Sr/Ca as a new                                                        carbonate system proxy, Geochim. Cosmochim. Acta, 202, 374 – 386, doi: 10.1016/j.gca.2016.11.022.

2016                       Langer G., Sadekov A., Thoms S., Keul N., Nehrke G., Mewes A., Greaves M., Misra S., Reichart G.-J., de Nooijer L.,                                 Bijma J., Elderfield H., Sr partitioning in the benthic foraminifera Ammonia aomoriensis and  Amphistegina lessonii,                                         Chemical Geology, 440, 206 – 312, doi:10.1016/j.chemgeo.2016.07.018.

2013                        Nehrke G., Keul N., Langer G., de Nooijer L. J., Bijma J., Meibom A., A new model for biomineralization and                                                        trace-element- signatures of foraminifera tests, Biogeosciences 10, 6759-6767, doi:10.5194/bg-10-6759-2013.

2013                        Keul N., Langer G., de Nooijer L. J., Bijma J., Effect of ocean acidification on the benthic foraminifera Ammonia                                 sp. is caused by a decrease in carbonate ion concentration, Biogeosciences 10, 6185-6198, doi:10.5194/                                                            bg-10-6185-2013.

2013                       Keul N., Langer G., de Nooijer L. J., Nehrke G., Reichart G.-J, Bijma J., Incorporation of uranium in benthic                                                            foraminiferal calcite reflects seawater carbonate ion concentration, Geochem. Geophys. Geosyst., doi:10.1029/                                              2012GC004330.

2012                        Glas, M., Langer, G., Keul, N., Calcification acidifies the microenvironment of a benthic foraminifer (Ammonia sp.),                                 Journal Mar. Biol. Ecol., 424-425, p53-58.

2010                       Keul, N., Morse, J. W., Wanninkhof, R., Gledhill, D. K., Bianchi, T. S., Carbonate Chemistry Dynamics of Surface Waters in                                 the Northern Gulf of Mexico, Aquatic Geochemistry, Vol 16, Nr 3, p337 –351.


2016                        Repschläger J., (et al., inkl. Keul N.), NASGAF: North Atlantic Subtropical Gyre and Azores Front Geometry,                                                        Cruise No. MSM58- September 10 – October 07, 2016 – Reykjavik (Island)- Ponta Delgada (Portugal), Maria S. Merian                                       Berichte, 2016.

2016                        Schneider R., (et al., inkl. Keul N.), LISA: Baltic Sea water budget and sediment transport changes since the                                                        Littorina Transgression and their effects on the ecosystem, Cruise No. MSM51-1 – February 01 – February 09,                                                  2016 – Warnemünde (Germany) – Kiel (Germany), Maria S. Merian Berichte, 2016.

2015                        Schneider R., (et al., inkl. Keul N.), PULSE: Paleoclimate- Understanding Labrador Sea, PULSE, Cruise No. MSM45 –                                          August 02 – August 21, 2015 – Nuuk (Greenlad) – Halifax (Canada), Maria S. Merian Berichte, 2015.

2015                        Keul N., Langer G., de Nooijer L. J., Nehrke G., Reichart G.-J, Bijma J., Schneider R., New Carbonate System Proxies:                                  Foram Culturing and Pteropod Potentials, Nova Acta Leopoldina NF 121 408, 305 – 309.

2007                        Hansen I. S., Keul N., Sørensen J. T., Erichsen A., Andersen J. H., Baltic Sea Oxygen Maps 2000- 2006 Balance Interim                                        Report No. 17.