|My research interests focus on the cycling of carbon, nitrogen, and phosphorus in the marine environment. The cycling of these elements is an essential part of the global climate system, and is also critical in supporting healthy marine ecosystems.|
The main focus of my research is to understand how land-derived organic carbon is processed biogeochemically at sea. South-East Asia's coastal peatlands are a globally significant source of dissolved organic matter to the ocean, but we do not understand well what happens to this organic matter at sea, and what the environmental consequences of this input are. Using a combination of in-situ observations, laboratory experiments, and remote sensing, we are trying to understand better how extensively this organic matter is degraded by microbial and photochemical processes, and how its presence influences light availability in coastal waters. We are also developing methods to better quantify land-derived organic matter in the sea both in the present (using optical spectroscopy and stable isotopes), and in the past (using palaeoceanographic reconstructions from coral cores).
Furthermore, I am interested in nutrient cycling processes in tropical coastal waters. Using time-series measurements, we are trying to understand how the rates of coral-associated nitrogen fixation are controlled by environmental conditions, and how the cycling rates and bioavailability of dissolved organic nitrogen and phosphorus on coral reefs are controlled. Nitrogen fixation is a potentially important process that contributes new nitrogen to coral reef environments, while the cycling of organic nitrogen and phosphorus is essential for maintaining productivity in nutrient-poor waters.
- Nikita Kaushal, Liudongqing Yang, Jani T.I. Tanzil, Jen Nie Lee, Nathalie F. Goodkin, Patrick Martin. (2020). Sub-annual fluorescence measurements of coral skeleton: relationship between skeletal luminescence and terrestrial humic-like substances. Coral Reefs, .
- Zhou Y., Martin P., Müller M. (2019). Composition and cycling of dissolved organic matter from tropical peatlands of coastal Sarawak, Borneo, revealed by fluorescence spectroscopy and parallel factor analysis. Biogeosciences, 16, 2733-2749.
- Martin P, Cherukuru N, Tan ASY, Sanwlani N, Mujahid A, Müller M. (2018). Distribution and cycling of terrigenous dissolved organic carbon in peatland-draining rivers and coastal waters of Sarawak, Borneo. Biogeosciences, 15, 6847-6865.
- Martin P, Lauro FM, Sarkar A, Goodkin NF, Prakash S, P. N. Vinayachandran. (2018). Particulate polyphosphate and alkaline phosphatase activity across a latitudinal transect in the tropical Indian Ocean. Limnology and Oceanography, , doi:10.1002/lno.10780.
- Martin P, Goodkin NF, Stewart JA, Foster GL, Sikes EL, White HK, Hennige S, Roberts JM. (2016). Deep-sea coral ∂13C: A tool to reconstruct the difference between seawater pH and ∂11B-derived calcifying fluid pH. Geophysical Research Letters, 43, 299-308.