Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: November 4, 1999
Publication Date: N/A
Technical Abstract: Water use efficiency represents a measure of the crop growth relative to water extracted from the soil. In this approach it is assumed that primary influence is from the environmental effects on crop growth and not on variations in the soil water availability. Soil management practices have a major impact on crop water use efficiency; however, the magnitude of the response is crop dependent. Crop residue reduces soil water evaporation rates and diverts this water into potential crop water use. Tillage can increase soil water evaporation and increase crop water stress early in the growing season, which can have a lasting impact on crop growth. Increasing soil water holding capacity through increases in soil organic matter has a positive effect on water use efficiency. Interactions of soil water and nutrient management will have major impacts on crop water use patterns. Variations of crop growth and yield across a field demonstrate variations in water use efficiency. Altering soil management practices can lead to improvements in water use efficiency that will have a positive impact on production efficiency.