Application of change detection techniques driven by expert opinions for small-area studies in developing countries

Rapid urbanisation in developing countries, driven by population growth and rural-to-urban migration, challenges service delivery in under-resourced municipalities. Dangamvura Township in Mutare, Zimbabwe, exemplifies this issue, potentially overwhelming the City of Mutare's services. Resource limitations have hindered the quantification of these changes. This study assesses land use and land cover (LULC) changes in Dangamvura Township, Mutare, Zimbabwe, between 2010 and 2022, using stakeholder-driven methods, Google Earth Pro (GEP), and machine-learning in R. A four-tier methodology integrating R and expert validation via GEP was applied to classify and quantify LULC changes. The analysis identified built-up areas, cropland, and bare land as the main classes. Results from R showed that built-up areas expanded from 3.74 km² in 2010 to 8.64 km² in 2022, bare land decreased from 3.10 km² to 1.42 km², and cropland declined from 6.06 km² to 2.84 km². GEP assessments indicated an increase in built-up areas from 5.08 km² to 8.91 km², a reduction in bare land from 3.57 km² to 1.97 km², and a decrease in cropland from 4.25 km² to 2.02 km² over the same period. These findings highlight significant urban expansion and declining agricultural and undeveloped lands. Disparities between R statistical software and GEP results underscore the importance of integrating expert opinions to validate classifications, particularly in small-area studies with spatial heterogeneity. The results provide valuable insights for urban planning and decision-making, emphasising the need for adaptive strategies to manage urban growth and infrastructure development. The tiered methodology demonstrates the potential of combining advanced remote sensing tools with local knowledge to achieve robust LULC assessments in resource-limited settings, guiding sustainable urban planning and informing policy interventions to address challenges associated with rapid urbanisation in resource-limited countries.