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Using Yucheng county with soil salinization as a typical area of the north China plain, spatial variability of maize yields was described and influence of the terrain attributes on maize yields were discussed by space interpolation techniques based on measuring maize yields in field and extracting terrain information. The results showed that maize yields gradually increased along the northeast to southwest of the county with increasing the elevation. Although terrain undulated very slightly, the increasing trend of the elevation was agreement with the distribution of yields from low to high. A very significantly positive correlation (R=0.263, p<0.01) existed between maize yields and elevation. Meanwhile, a significantly negative correlation (R=-0.245, p<0.05) existed between maize yields and plane curvature, indicating that the bigger plane curvature, the easier saline accumulation leading to decreased maize yields. The combined effects of elevation and plane curvature explained 12.4% of the observed variability of maize yields.