Uncharted Territory: mapping diverse and dispersed smallholder irrigation in sub-Saharan Africa through Remote Sensing

Samenvatting

There has been a growing interest in irrigation in sub-Saharan Africa to meet the region's rising food demands. Smallholder farmers have long been the driving force behind irrigated agriculture through farmer-led initiatives. Unfortunately, these efforts often go unnoticed due to their fragmented nature and technical biases in defining irrigation. Mapping these systems using remote sensing faces challenges such as spectral signature similarities, mixed signatures within the same class, and subjective irrigation definitions. Despite these challenges, remote sensing offers broad spatial coverage and temporal monitoring advantages. This thesis explores remote sensing's effectiveness in depicting irrigated agriculture, focusing on four diverse locations in Mozambique. It identifies challenges in mapping and highlights the impact of choices in classification processes. The study also assesses the influence of algorithms, composite lengths, training sample size, and geographical transferability, emphasizing the importance of methodological transparency in remote sensing-based classifications. Ultimately, it sheds light on the democratization of remote sensing but stresses the need for careful consideration and reporting of methodological choices in mapping irrigated agriculture.