Evaluation of Soil-N Distribution and Corn Yield in Fertigation Systems

Abstract

In Korea, field crop yields are steadily declining due to drought though it can be managed through irrigation. To address this problem, irrigation technology using subsurface drip line (SDL) has only recently been developed and distributed in Korea. In this study, fertilizer was supplied through SDL while growing corn on the arable land where SDL were buried. SDL was installed and a venturi system was connected for fertilizer injection. Irrigation and fertigation were controlled by connecting to the control panel. During corn cultivation, soil moisture levels were maintained at 100% and above 100% of the field capacity by soil moisture sensor. Nitrogen amounts and distributions of nitrate contents were measured by distance from SDL. Corn growth and yield characteristics were also measured. As a result, the total amount of nitrogen by distance released from the SDL was uniform, When evaluating the distributions of nitrate contents in the soil released from the SDL, NO3 was spread first to the upper part of the soil (after 1 day). And, after 9 day NO3 was spread evenly over the upper part of the soil rather than leaking to the lower part. It was determined that nutrients could be stably supplied to crops. There was a tendency that weight and diameter of ear during the growth of corn were greater than those supplied with topsoil, and the corn yield was also increased. Subsurface drip fertigation system is expected to have a positive effect on agricultural automation for better agriculture production.Distributions of nitrate content in the soil released from the subsurface drip over time; red dot: location of subsurface drip line, unit of legend: nitrate concentration (mg kg-1) - Each color represents a certain range of values, nday: n day after fertigation.