Tuesday, November 6, 2007
231-47

Developing Environmentally Sound Corn Production System Based on Evaluation of N Movement in the Soil across Different Soil Zones and Tillage Systems.

Pawel Wiatrak, Ahmad Khalilian, Brad Hammes, Will Henderson, and Richard Hallmen. Clemson University, Edisto REC, 64 Research Road, Blackville, SC 29817

Soil nitrate and other nutrient leaching is the reason for environmental and health concerns due to soil and groundwater pollution. Nitrogen added to the soil is converted to the nitrate-nitrogen (NO3-N) in the presence of moisture. The movement of nitrates in the soil needs to be tracked in order to evaluate the nitrate pollution of underground water. Nitrogen applied at once may be a great source of nitrate leaching, because plants may not be able to utilize all of applied N. Splitting fertilizer application may help to better utilize nitrogen by plants. Therefore the component of splitting N in this study will help to determine the most efficient nitrogen application method and better utilize N by corn, and therefore reduce nitrate movement into the underground water. A commercially available soil electrical conductivity (EC) measurement system (Veris Technologies 3100) will be used to identify variations in soil texture across the field and create soil zone maps using GPS and geographic information systems. Within each soil zone, there will be three tillage systems (conventional, strip-till, and no-till) with two N application methods (all at once and as split) and five different application rates (0, 45, 90, 134, and 179 kg N ha-1). Generally, soil sampling at different levels will help to quantify nutrient movement, especially nitrate leaching under different soil zones and tillage systems. This information will help to develop environmentally sound production systems.