Abstract: The possible difference of temporal-spatial variation characteristics of soil moisture conditions caused by calculating with different meteorological data sets was explored in this study, to identify the effect of two type of data sets, one from all of the meteorological stations and another only the standard stations, on the calculation results of temporal and spatial rainfall amount, crop evapotranspiration and crop water deficit during growth periods of winter wheat in the North China Plain. The results showed that, (1) annual average precipitation in growth period of winter wheat in North China Plain showed an unobvious trend from 1960s to 2010s, and reference crop evapotranspiration showed a trend of decrease, while the crop water deficit rate declined and had a larger difference in inter-decadal variation; (2)The precipitation, reference crop evapotranspiration and crop water deficit rate were in obviously latitudinal distribution. The precipitation decreased with the increase in latitude, accordingly, the referencecrop evapotranspiration increased as well as the crop water deficit rate due to low precipitation. Compared with the results based on data from the standard stations, in terms of time variation, the change trend is relatively consistent. However, from the point of value, the average precipitation and reference crop evapotranspiration of standard stations were higher than all stations. Generally speaking, the spatial distributions based on both are consistent, but there is large difference in some terrain areas, which have bigger variability.

Key words: Winter wheat, Crop water deficit index, Benchmark stations, North China Plain