Research

Current Projects

Phytoplankton trace metal requirements at different environmental conditions

Phytoplankton are organisms positioned at the bottom of the marine food chain and they are the basis of the marine ecosystems. The growth and distribution of marine phytoplankton are controlled by nutrients, including trace metals, present in the environment. These trace metals are co-factors of many enzymes that control carbon fixation, phosphorus uptake, and remineralisation. Therefore, their availability in the marine environment can regulate the growth and functions of phytoplankton, and even dictate the global rate of oceanic carbon export to the deep ocean. Key environmental factors such as temperature and light might influence trace metal requirements of different phytoplankton functional groups in the marine environment. We aim to get a comprehensive understanding of trace metal requirements of representative phytoplankton functional groups under different light intensities and temperatures, which vary across the global ocean, along water columns, and under climate change.

Controlling mechanisms of coccolithophore distribution in the modern ocean

The calcifying marine phytoplankton of the class Prymnesiophyceae, coccolithophores, can contribute to 10% of primary production and 50% CaCO₃ production in the ocean, and therefore, they play an important role in the global carbon cycle. Although different environmental conditions, such as light, phosphorus concentrations, and pH, are shown to have significant impacts on the growth and calcification processes of Emiliania huxleyi, a ubiquitous coccolithophore, the relative importance of different environmental factors that control the distribution of the diverse community of coccolithophores in the modern ocean remains unclear. We evaluate the relative importance of different environmental factors on coccolithophore production in the modern ocean, including light, temperature, macronutrients (N, P, Si), micronutrients (Fe, Mn, Zn, Cu, Cd etc), carbon species (CO_2aqueous, CO₃, HCO₃), pH, abundance of other phytoplankton (e.g. diatom, dinoflagellates, cyanobacteria). We will take advantage of the rapid expansion of global databases available and employ a wide diverse of methods, including data synthesis, diagnostic modelling, empirical culture experiments, and deep learning, to elucidate the driving mechanisms that control coccolithophore production in the ocean.