Effect of Soil Aeration On Runoff Water Quality and Quantity in No-till Wheat Systems.

Each year depending on market conditions, up to 75 percent of wheat planted in Texas may be grazed, and of that, it has been estimated that as much as 95 percent is under conventional tillage. There is a perception among some producers considering no-till production that using no-till in dual-use wheat systems will increase compaction and therefore reduce water infiltration and decrease yields.  One management practice to potentially reduce compaction and/or increase water infiltration is the use of an AerWay aeration system in no-till dual-use systems.   Tillage treatments were applied prior to planting to determine the impact of different tillage operations in dual-use wheat on the quantity of runoff, water quality and nutrient movement.  Treatments included: conventional-till, no-till and no-till with AerWay offsets at 0, 2.5, 5, 7.5 and 10 degrees. Rainfall simulators were used to provide a 7 cm hr^-1 storm event in order to achieve 30 min continuous runoff from small runoff plots (1.5 x 2 m).  Initial results from the first simulation study in December showed that runoff came quickest and in the highest quantity from conventional-till plots. Total amounts of ammonium, phosphorus, and sediment were also highest from conventional-till plots.  There was no statistical difference in runoff volume, soil erosion and nutrient runoff amounts between the no-till plots and the aerated treatments.  These initial results show that the use of an AerWay may not be economical, based solely on soil and water conservation.  Grazing effects and grain yields may indicate otherwise as the study continues.