Fig. 4

Sketch map of location changes in the centre of gravity after cultivated land converted to other land use types. (a: the position of the centre of gravity of cultivated land during the period from 2010 to 2015; b: land use conversion of cultivated land during the period of 2015 to 2020; c: the position of the centre of gravity of unchanged cultivated land; d: the centre of gravity position after converting cultivated land into building land; e: the position of the centre of gravity after converting cultivated land into forest land; f: the position of the centre of gravity after converting grass land into grass land; g: the position of the centre of gravity after converting grass land into water; h: the position of the centre of gravity after converting cultivated land into unused land).