About the Partnership
This project is one of a number that are in competition for funding from the NERC Great Western Four+ Doctoral Training Partnership (GW4+ DTP). The GW4+ DTP consists of the Great Western Four alliance of the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus five Research Organisation partners: British Antarctic Survey, British Geological Survey, Centre for Ecology and Hydrology, the Natural History Museum and Plymouth Marine Laboratory. The partnership aims to provide a broad training in earth and environmental sciences, designed to train tomorrow’s leaders in earth and environmental science.
Project Background Lowland1 and montane2,3 tropical forests are recognised as large carbon stores with Andean tropical montane forest identified as a ‘biodiversity hotspot’ where exceptional amounts of endemic species are undergoing loss of habitat. However due to their thermal specialisation, they may be highly vulnerability to future climate warming4. Data from adult and juvenile trees in the tropical Andean forest show a change in composition in these forests, suggesting an increase in warm-affiliated species across elevations -thermophilisation- and mortality of cold-affiliated species in the hotter portion of their thermal ranges6,7.
Thus, current climate warming is already affecting the function of these critically important forests and the biodiversity they contain, but we have limited understanding of what will happen in the future. Increased warming will affect plant survival which strongly depends on the balance of photosynthesis and plant respiration, with consequences for the carbon balance of these ecosystems and the global carbon balance. However, most of the focus in the recent literature has been on warming responses of photosynthesis but relatively little is known about warming responses of plant respiration and specifically in the tropics. Night-time warming which affects both plant respiration and growth has been proposed as key factor influencing tropical forest productivity5.
This PhD project is focused on plant respiration in the tropical montane Andes of Colombia where in 2019 the supervisory team set up in 2019 experimental plantations of juvenile trees of dominant species across an elevation/thermal gradient to investigate warming responses of warm and cold-affiliated species in this biodiversity hotspot (part of a larger NERC funded project). Tree growth responses to warming have been monitored during 3 years in this experiment, and agree with observations from natural forest, but cannot fully be explained by carbon uptake through photosynthesis. We hypothesise plant respiration responses to warming in the experiments will contribute to explaining the observed tree growth responses in both the experiment and the natural forest. It is therefore critical that we better understand C release from the plants through respiration.
Project Aims and Methods The overall aim of the project is to understand and quantify plant respiration responses to warming across our experimental site, and test whether these responses can explain the observed growth responses to warming. The project offers an incredible opportunity to do research in an experimental facility in the Colombian Andes within two existing NERC projects in which observations of growth, photosynthesis and thermal traits have been taken during the last three years and heat stress responses will be measured in 2024. The project will answer key scientific questions of tropical forest function and will generate high-quality outputs. The student would use state-of-the-art equipment to measure plant respiration, and be involved in the development of stem respiration chambers for the requirements of the project. Collected data sets are of immense use for development and evaluation of plant respiration modelling. A modelling component can be incorporated based on student skill and interest. There is scope for flexibility within the project, allowing the student to bring their own ideas to project design.
Candidate requirements We look for a strongly motivated and independent candidate with understanding of plant carbon-climate interactions preferably with field and or lab experience. The student should be able to work in the field under challenging tropical climate conditions including taking nocturnal measurements under very safe conditions. A practical person in the field and lab to design stem respiration chambers is highly desirable. The candidate should be numerically skilled with experience with data analysis and coding in either R, python or similar programming languages.
Project partners The teams from Exeter, Edinburgh, UKCEH and Denmark will provide expertise in plant physiology, measuring and data analysis methods, vegetation modelling and tropical forest ecophysiology. Project collaborators in Colombia and UK team members from the Montane-Acclim and Trop-Heat NERC funded projects will provide expertise in Andean forest ecology and plant physiology. The link to UKCEH and UoE offers the opportunity to incorporate findings into the UK land surface model (JULES).
Training In addition to generic skills training, the student will receive specific training on i) methods needed for data collection and designing an experimental protocol and stem chambers for fieldwork, ii) Python or R coding and data (statistical) analysis required for data collected. Training in vegetation modelling (JULES model) also available based on student interest with expertise in UoE and UKCEH.
For further information and to submit an application please visit - https://www.exeter.ac.uk/study/funding/award/?id=4600