Same trend was found from the field experiment, K application increased corn yield by 39. 1% in the aeolian sandy soil, 24. 5% in the light chernozem soil, and 14. 9% in the black soil.

• 田间试验亦有相同趋势，在风砂土、淡黑钙土和黑土试验地上施用钾肥分别使玉米增产39.；1%25、24