Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Effect of Drainage Water Management on Nitrate Nitrogen Loss to Tile Drains in North Carolina  Public Access Limited Time

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan

Citation:  Transactions of the ASABE. 61(1): 233-244. (doi: 10.13031/trans.12296) @2018
Authors:   Chad A. Poole, R. Wayne Skaggs, Mohamed A. Youssef, George M. Chescheir, Carl R. Crozier
Keywords:   Controlled drainage (CD), Corn, Drainage water, Drainage water management (DWM), Nitrate, Nitrogen, Soybean, Water quality, Wheat.

Abstract. Short-term studies have demonstrated that drainage water management (DWM), or controlled drainage (CD), can be used to substantially reduce the loss of nitrogen (N) from drained lands for a wide range of soils, crops, locations, and climates. Long-term studies on the effects of the practice are limited. This article presents results on the effects of CD on nitrate-N (NO3-N) losses for three crops, corn ( L.), wheat ( L.), and soybean ( [L.] Merr.), in a two-year rotation in North Carolina. Nitrate losses were measured on replicated plots under CD and conventional, or free drainage (FD), treatments for nine years between 1992 and 2012 on a tile-drained site near Plymouth, North Carolina. The site is on a Portsmouth sandy loam soil with parallel drains 22.9 m apart and 1.15 m deep. The subsurface drainage characteristics under FD were drainage intensity (DI) = 8 mm d-1, drainage coefficient (DC) = 14 mm d-1, and Kirkham coefficient (KC) = 18 mm d-1. Compared to FD, CD reduced annual drainage outflow by 33% and NO3-N export by 30%, with an average annual reduction of 6.3 kg ha-1 year-1. CD increased average NO3-N concentrations by 0.9 mg L-1, but the difference was not significant. The reduction in NO3-N export observed in the CD treatment was equal to the increase in N removed by the harvested grain. The results document the effects of CD on NO3-N export over a wide range of weather conditions during the nine-year study. While the average 30% reduction in NO3-N losses in drainage water is in the midrange of that reported by previous studies for different soils and climates, this is believed to be the first time such a reduction has been attributed to the effect of CD on increasing yields and N removed in the harvested grain.

(Download PDF)    (Export to EndNotes)