Geophysics for Climate-Smart Agriculture in Africa

Soil physics offers key tools both to understanding climate change impacts on agriculture, and to best design climate-resilient agricultural systems - ensuring food and economic security in regions like sub-Saharan Africa. However, much greater transfer of technology and knowledge is needed to facilitate better adaptation to climate change in those regions. A specific scientific challenge is to evaluate the impact of agricultural interventions such as cover-cropping on water dynamics in soil and the impacts on cropping, groundwater and greenhouse gas budgets. Our project will establish a lasting Africa-UK physics partnership by jointly designing and developing geophysical soil sensing technology and deploying this to monitor agricultural experiments in Ghana. Specifically, UK geophysicists from the British Geological Survey will team up with physicists at Kwame Nkrumah University of Science and Technology to collaboratively build and install low-cost electrical resistivity tomography (ERT) instrumentation from first principles, utilising open-source hardware and software recently made publicly accessible by the OhmPi project. ERT monitoring arrays will facilitate the high-resolution imaging of soil water dynamics within the root zone of crops in both space and time, thus providing 4D models of soil water content in the shallow subsurface in near-real-time. ERT sensor arrays along with a variety of other soil sensors measuring complementary parameters will be deployed at ongoing agricultural experiments at the Council for Scientific and Industrial Research - Crops Research Institute (CSIR-CRI), the leading agricultural research organisation in Ghana. The experiments investigate the value of intervention measures to make agricultural practice more climate-resilient, including inter-cropping, different tillage practices and crop residue management. Monitoring these experiments with state-of-the-art soil physics methodologies will provide crucial information about soil...