Skip to main content
ARS Home » Midwest Area » Ames, Iowa » National Laboratory for Agriculture and The Environment » Agroecosystems Management Research » Research » Publications at this Location » Publication #409782
Research Project: Sustainable Intensification in Agricultural Watersheds through Optimized Management and Technology

Location: Agroecosystems Management Research

Title: Nutrient leaching from an artificially drained Midwestern Mollisol across various conservation practices

Author
item Rogovska, Natalia
item Kovar, John
item Malone, Robert - Rob
item O'Brien, Peter
item Emmett, Bryan
item Ruis, Sabrina

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/23/2023
Publication Date: 11/2/2023
Citation: Rogovska, N.P., Kovar, J.L., Malone, R.W., O'Brien, P.L., Emmett, B.D., Ruis, S.J. 2023. Nutrient leaching from an artificially drained Midwestern Mollisol across various conservation practices [abstract]. ASA-CSSA-SSSA Annual Meeting.

Interpretive Summary:

Technical Abstract: Leaching of soil nutrients largely depends on inherent soil properties, fertilizer nutrient management, and adoption of conservation practices. While the effect of different conservation practices on nitrate leaching has been widely documented, their effect on leaching of other essential soil nutrients is less well known. A replicated plot experiment was initiated to quantify the effectiveness of various conservation practices on losses of N, P, K, and S via subsurface tile drains. Maize (Zea mays L.) and soybean (Glycine max L. Merr.) were grown in alternate years with four different treatments: 1) Basic management with spring application of 196 kg N ha-1 in maize years and fall chisel plow tillage (Basic); 2) No-till management (NT), 2) No-till with a winter rye (Secale cereale L.) cover crop (RC), and 4) No-till with an in-situ woodchip denitrification wall (DW) where trenches were excavated parallel to the tile on both sides and filled with woodchips. The three conservation treatments (NT, RC and DW) received 155 to 213 kg N ha-1 depending on pre-sidedress soil nitrate test. All four treatment received the same rates of P and K in either maize or soybean years. Annual drainage flow varied among years and depended on annual precipitation but was not affected by treatments. Averaged across seven years (2016-2022), the DW and RC treatments had the lowest NO3--N leaching losses: 8.2 kg N was lost from DW plots, 5.8 kg N from RC; 18 kg N from NT; and 15.5 kg N was leached from the Basic plots. The DW treatment resulted in a 50% increase in K leaching compared to Basic treatment, while adoption of conservation practices did not have an effect on leaching of P and S. We hypothesize that K release during decomposition of woodchips in the denitrification walls contributed to increased values of K in drainage waters. The Basic treatment consistently produced the highest maize yields, while no yield differences were observed among treatments in soybean years. Overall, treatment and annual drainage flow had the greatest effects on annual nutrient loss in drainage.