Effect of Level Terraces on Soil Moisture Content and Utilization by Corn
1973
Miller, E. L. | Shrader, W. D.
Field experiments were conducted to determine the effect of sod-stabilized backslope level terraces on soil moisture content and the utilization of moisture by corn (Zea mays L.). Plots were located in the terrace interval and in terrace channel positions up-slope from 9 different terraces, on a watershed, in the Ida-Monona soil association area of southwestern Iowa. Periodic measurement of soil moisture in the root zone, daily observation of weather variables, and corn development and yield measurements were made for each plot and were used to evaluate soil moisture content and utilization by corn. Soil moisture amounts in the rooting zone were greater in terrace channels than in terrace interval positions on all sample dates, with differences ranging from 1.98 to 6.27 surface cm and averaging 5 cm in the surface 1.83 m of soil. Significant yield differences between positions occurred, and moisture-stress intensity was a significant factor in explaining yield variation. Other factors that were significant in explaining the variation in yield were plant density and plant nitrogen and phosphorus contents. A yield-response curve was developed, which characterized the relationship between corn yield and moisture stress intensity.
显示更多 [+] 显示较少 [-]