The researchers used satellite data to track how often farmers in Guangdong Province grow crops on their fields. They found that most paddy fields in the area are used for growing rice twice a year. Some fields are also used for growing other crops like peanuts, sweet potatoes, and sugarcane alongside rice. The researchers used different methods to analyze the data and found that one method was better at showing the planting patterns in the fields. They also discovered that some fields were left empty, especially near urban areas like the Guangdong-Hong Kong-Macao Greater Bay Area.