Advanced practice-aided tile drain configuration: A solution to achieving environmentally sustainable agricultural production

Alternatives to conventional crop production practices are needed to achieve environmental sustainability. Because tile-drained crop production systems in the Midwestern United States are one of the single largest contributors to environmental degradation, we explored alternative tile drain configurations by changing the tile spacing and depth of tile-drained fields in central Illinois and then by evaluating comprehensively the impacts of different tile drain configurations on crop productivity and environmental sustainability using the Root Zone Water Quality Model 2 (RZWQM2). An analytic hierarchy process (AHP), which is a multicriteria decision analysis (MCDA) tool, was used to evaluate the optimum tile spacing and depth scenario. The model simulations and AHP tested three management schemes designated as “agricultural productivity” (AP), “environmental sustainability” (ES), and “advance in technology” (AT). The schemes were designed based on three criteria: operational cost, crop profit, and environmental control. Analysis showed that deeper tiles and narrower tile spacing resulted in decreases in flow and nitrate loss from runoff, seepage (SP), and lateral flow (LF), and increases in tile flow, total nitrate loss, and crop yields. On the basis of MCDA, the AP management scheme resulted in higher CP and total nitrate loss, whereas opposite outcomes were generated by the ES management scheme. Under the AT management scheme, higher ranked scenarios resulted in higher CP and lower total amounts of nitrate entering streams. Our analysis indicates that the AT scheme can simultaneously enhance crop production and ES through advances in tile drainage water treatment.