Maria Mills

University of Leicester


Understanding carbon fluxes along a logging gradient in Malaysian Borneo


  • Dr Juan Carlos Berrio
  • Dr Joerg Kaduk
  • Prof Susan Page
  • Dr Terhi Riutta

PhD Summary

My PhD focuses on how carbon fluxes vary across a logging gradient from old-growth unlogged to heavily logged forests in Sabah, Malaysian Borneo. Logged forests are increasingly becoming a prevalent part of the tropical forest biome and are more widespread than old-growth forests in most areas. Yet, research into logged tropical forests has been limited, with previous research largely focusing on old-growth forests within the tropics. Given how widespread these logged forests are, it is imperative that we improve our understanding of them so they can be better represented within the global carbon budget.

This research will quantify and compare carbon fluxes along the logging gradient and investigate what similarities or differences there may be between logged and unlogged old-growth forest landscapes. I will use a secondary dataset from long term monitoring plots to quantify the complete carbon budget along this gradient and provide direct measurements of net CO2 exchange over a heavily logged landscape using eddy covariance. I will also investigate the biotic and abiotic drivers of these similarities or differences in carbon fluxes along the logging gradient, with a specific focus on respiration from tree stems. Finally, I will collect a primary dataset to investigate the accuracy of the measurements themselves. I will explore how traditional ways of estimating respiration from tree stems may introduce bias into these measurements and quantify the associated error.

Previous activity

Before starting my PhD, I undertook an undergraduate degree in Physical Geography at the University of Sheffield followed by a Master of Research at Imperial College London in Tropical Forest Ecology. During my undergraduate degree I became interested in forestry landscapes and their global importance. This led me to undertake a summer school at the University of Helsinki in managing suitable forest landscapes. This course was interdisciplinary and provided a global perspective covering topics such as forest-atmosphere interactions, ecosystem services and functions, and risk and vulnerability to climate change. This fuelled my desire to continue studying forest landscapes and continue with research. I then completed a master’s degree where my research focused on the impact of selective logging and forest degradation on carbon fluxes in Malaysian Borneo.

Why did you choose doctoral research?

Between my undergraduate and master’s degree I spent a year working in sales. It was during this time that I realised that wanted to make a contribution to science and that I have a passion for field ecology. I truly enjoyed my master’s research and want to build upon improving the understanding of tropical carbon dynamics.

Why did you choose CENTA?

The CENTA studentship delivers a wide range of training opportunities that will complement my research and will provide me with a variety of transferrable skills necessary for both industry and academic future endeavours. All these training opportunities are necessary to make me into the best possible researcher I can be and with the confidence I need for all aspects of research. The project offered by CENTA suited my research interests perfectly and is supervised by academics who are leading in their fields.

Future plans

Following my PhD I would either like to continue in academic or work in long-term ecosystem monitoring. This DTP will provide me with the training, experience and transferrable skills for either opportunity.