People > Gemma Kulk

Gemma Kulk

Phytoplankton physiologist

Contact Details

+44 (0)1752 633100 (switchboard)


Gemma specialises in the photophysiology and primary production of marine phytoplankton. She trained as a marine biologist at the University of Groningen (Netherlands) and Stanford University (USA).

Over the past 10 years, Gemma has combined laboratory experiments with field measurements in the North Atlantic Ocean, Mediterranean Sea, the Arctic Ocean and the western Antarctic Peninsula to study the response of marine phytoplankton to changing environmental conditions. She is especially interested in the role of phytoplankton in the ocean’s carbon cycle. Her work has been published in high impact journals and at international conferences.

Gemma has supervised BSc and MSc students at the University of Groningen and has been involved in outreach activities at secondary schools in the Netherlands.

At PML, Gemma will continue her work on phytoplankton primary production using ocean colour remote sensing. She is currently involved in the ‘Rehabilitation of Vibrio-Infested waters of Lake Vembanad (REVIVAL)’ project, investigating the role of lake ecosystems in Cholera epidemics in the South-West of India.


Biological Pump and Carbon Exchange Processes (BICEP)

Contact: Dr Shubha Sathyendranath

The ocean carbon cycle is a vital part of the global carbon cycle. It has been estimated that around a quarter of anthropogenically-produced...

Rehabilitation of Vibrio-infested waters of Lake Vembanad, funded under the India-UK Water Quality programme (REVIVAL)

Contact: Dr Shubha Sathyendranath

Lake Vembanad is the largest body of water in Kerala, India, stretching almost 100km in length and spanning an area of over 2000km2. Its shores are...

Selected key publications


Kulk, G., Van de Poll, W.H., Buma, A.G.J. (2018). Photophysiology of nitrate limited phytoplankton communities in Kongsfjorden, Spitsbergen. Limnology and Oceanography, doi:10.1002/lno.10963.


Rozema, P.D., Kulk, G., Veldhuis, M.P., Buma, A.G.J., Meredith, M.P., Van de Poll, W.H. (2017). Assessing drivers of coastal primary production in Northern Marguerite Bay, Antarctica. Frontiers in Marine Science, doi: 10.3389/fmars.2017.00184.


Kulk, G., Van de Poll, W.H., Visser, R.J.W., Buma, A.G.J. (2013). Low nutrient availability reduces high irradiance induced viability loss in oceanic phytoplankton. Limnology and Oceanography 58: 1747-1760. doi: 10.4319/lo.2013.58.5.1747


Van de Poll, W.H., Kulk, G., Timmermans, K.R., Brussaard, C.P.D., Van de Woerd, H.J., Kehoe, M.J., Mojica, K.D.A., Visser, R.J.W., Rozema, P.D., Buma, A.G.J. (2013). Phytoplankton chlorophyll-a biomass, composition, and productivity along a temperature and stratification gradient in the northeast Atlantic Ocean. Biogeosciences 10: 4227-4240. doi: 10.5194/bg-10-4227-2013


Kulk, G., De Vries, P., Van de Poll, W.H., Visser, R.J.W., Buma, A.G.J. (2012). Temperature-dependent growth and photophysiology of prokaryotic and eukaryotic oceanic picophytoplankton. Marine Ecology Progress Series 466: 43-55. doi: 10.3354/meps09898


Alderkamp, A.C., Kulk, G., Buma, A.G.J., Visser, R.J.W., Van Dijken, G.L., Mills, M.M., Arrigo, K.R. (2012). The effect of iron limitation on the photophysiology of Phaeocystis antarctica (Prymnesiophyceae) and Fragilariopsis cylindrus (Bacillariophyceae) under dynamic irradiance. Journal of Phycology 47: 45-59. doi: 10.1111/j.1529-8817.2011.01098.x


Kulk, G., Van de Poll, W.H., Visser, R.J.W., Buma, A.G.J. (2011). Distinct differences in photoacclimation potential between prokaryotic and eukaryotic oceanic phytoplankton. Journal of Experimental Marine Biology and Ecology 398: 63-72. doi: 10.1016/j.jembe.2010.12.011