This research looked at how cities growing and saving farmlands relate. Cities growing can have good and bad effects on saving farmland, depending on when and how big a city becomes. The study focused on Hebei province from 1985 to 2008. They studied how urban areas grew and what happened to farmlands in that time to see how cities affected saving farmland. The researchers found that the relationship between urban growth and farmland protection changes over time and with city size. They suggest ideas for cities to develop and save farmlands together.