Measuring the climate-smart practices using crop modelling, machine learning and remote sensing

There is an urgent need for food production systems to become more resilient to climate change, whilst also increasing productivity and reducing agricultural greenhouse gas emissions. Climate-smartness is a term that refers to simultaneously achieving these three objectives. Measuring progress towards climate-smartness is a critical challenge (Challinor et al., 2022) and forms the focus on this studentship.

Remote sensing (RS), crop modelling and machine learning (ML) have significant potential to improve regional-scale measurements of climate-smartness.

The work will focus initially on crop productivity modelling in Kenya where models are proving highly promising - using the very latest developments in using ML with RS, as part of the EU Horizon 2020 project CONFER. Work so far has begun to form a new hybrid process-based and ML crop model with three core elements: i. crop phenological stage (pre anthesis - post anthesis - maturity); ii.

Radiation Use Efficiency (RUE); and iii. daily change in harvest index (dHI/dt). NDVI data from MODIS (years 2010 - 2021) has been downloaded and partially analysed. The project will start with maize in Kenya, where significant advances have already been made, leaving a clear plan for the new crop productivity model:

Develop a parameterisation to estimate the crop rate of change of harvest index (dHI/dt) using NDVI for each pixel in Kenya. Calculate RUE from end-of-season yield and biomass, using the method of Droutsas et al. (2022).

Simulate maize using remotely-sensed NDVI in Kenya as inputs, via the dHI/dt, RUE and phenological stage parameterisations.

The project can then turn to the second objective of climate-smartness, that of reducing greenhouse emissions. Here, a range of options will be scoped before deciding which method(s) to develop. Options include the agricultural environmental impact calculator, Cool Farm Tool, which estimates greenhouse gas emissions, water use, and biodiversity; and climate-smart indicators, which combine assessments of the three objectives of climate-smart agriculture into a single metric.