유공암거 배수 구성: 환경지속가능성과 농업생산성 사이의 균형

This study evaluated the impacts of subsurface drainage design, i.e., spacing and depth, on agricultural productivity and environmental sustainability intwo tile-drained fields (Sites A and E) under a corn-soybean rotation in the Midwestern United States. A calibrated and validated Root Zone WaterQuality Model (RZWQM) was used to simulate Nitrate-N (nitrogen) losses to tile drainage and crop yields of 30 tile spacing and depth scenarios over24 years (1992-2015). Our results presented that the narrower and deeper the tile drains are placed, the greater corn yield and Nitrate-N losses,indicating that the subsurface drainage design may cause a trade-off between agricultural productivity and environmental sustainability. The simulationresults also presented that up to about 255.7% and 628.0% increase in Nitrate-N losses in Sites A and E, respectively, far outweigh the rate of increasein corn yield up to about 1.1% and 1.6% from the adjustment of tile spacing and depth. Meanwhile, the crop yield and Nitrate-N losses accordingto the tile configuration differed depending on the field, and the soybean yield presented inconsistent simulation results, unlike the corn yield, whichtogether demonstrate the heterogeneous characteristic of agro-environmental systems to a subsurface drainage practice. This study demonstrates theapplicability of agricultural systems models in exploring agro-environmental responses to subsurface drainage practices, which can help guide theintroduction and installation of tile systems into farmlands, e.g., orchards and paddy fields, in our country.