The upper reaches of the Weihe River and adjacent areas of the Xihanshui River is a part of the Loess Plateau west to Longshan Mountain and the northern Qinling Mountain,which is made up of the Valley Plain,the Loess hills and earth-rock mountains.In primitive society,Cultural methods changes from ash-pit-dibbling cultivation to fire-farming cultivation,then to bush-fallow cultivation.With cultivating methods evolution,the agricultural land-use pattern changes from scattered point to point-shaft,to point-shaft and shape-like strip.This process is essentially a land-use space by the river valley expanding to the loess hills,then to earth-rock mountain,the use of agricultural land in primitive society lays a future land-use pattern.
