The researchers used remote sensing and GIS technology to study land use changes in Guangzhou. They analyzed satellite images from 1997 and 2003 to classify different land types and track changes over time. The study found that orchards, forests, and rural areas were more prevalent in 2003, while the areas of disk-ponds and unused land decreased. Urban and rural areas and newly developed zones increased. The rate of change was highest in newly developed zones and urban and rural areas. Regional differences in land use changes were also observed, showing varying transformations in different areas.