How effective would agroforestry be in the UK and where and when should we deploy it?

Background

Agroforestry is the practice of planting both trees and crops (or grazing livestock) in the same fields at the same time. Whilst, perhaps in present UK climates, it might be argued that the shading provided by trees would lead to a reduction in yields, that same shading may lead to resilience of crops and livestock in a warming climate. The trees also provide carbon sequestration, contributing to Net Zero, and may lead to enhanced biodiversity and water quality. However, agroforestry models require a lot of data to calibrate and UK field trials are limited and do not cover the possible combinations of crop rotation and tree species. Further, the UK climate is changing, so we really need to know how agroforestry would perform in the future and whether its benefits outweigh the risks to traditional farming in a warming world.

PhD Opportunity

Government can invest in a lot of agroforestry now or in a careful rollout designed to resolve critical uncertainties ready for wider deployment. Can we quantify the current benefits and risks to mass rollout now? What sort of payment incentives would be required to deliver mass uptake and what is the opportunity cost of backing agroforestry vs other options (e.g. forestry)? How does data from a staged rollout inform the next level of rollout and what is the value of information from existing and pioneering trials as we move through the next decade? Such questions can only be answered by combining decision theory, agroforestry modelling and uncertainty quantification. We would start by using the agroforestry models developed within LEEP recently and using Bayesian calibration techniques (taught as part of the standard training in the CDT) to understand how data from agroforestry field trials would resolve uncertainty in model projections of yields and carbon sequestration over this century. Armed with these tools, we can then address key questions for policymakers and individual farmers. What is the best way to trial or roll out agroforestry, at farm or national scale, in order to resolve enough uncertainty to discover whether it is cost effective or whether other land use options are more effective or profitable. Designing a national scheme of field trials to eliminate the resolvable uncertainty as quickly as possible to enable UK agriculture to adapt is of significant interest to policymakers. This PhD would seek to deliver a credible policy solution.

Applicant Profile

Students who have a strong numerical background in economics, econometrics, statistics or machine learning and with an ability to code and who want to apply their skills to real policy questions would be well suited to this PhD.

Other information

https://experts.exeter.ac.uk/24757-brett-day
https://www.exeter.ac.uk/research/leep/