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Vertical gradient observation is one of the most prominent characteristics for automatic farmland microclimate observation. There are different vertical gradient design schemes, which result in the observed data comparability and value reduced in the agrometeorological operational observation, because of the wide variety of farmland microclimate and complex surface vegetation conditions in the theoretical and applied research fields. Based on the observed data of microclimate stations during the whole winter wheat and maize growth periods in 2012 in Tyan and Zhengzhou, the vertical gradient variation characteristics of temperature and bare temperature and vertical gradient design standards for farmland microclimate are studied. The results indicate that the vertical gradient characteristics of temperature have a good consistency with bare temperature in time and space. According to the bare temperature vertical gradient variation in the wheat and maize fields, taking into account the restrictions of radiation shield heights, the observation heights should be set at 25 cm, 50 cm and 150 cm above the ground for wheat fields, respectively, while the observation heights should be set at 25 cm, 50 cm ,150 cm and 300 cm above the ground for maize fields.