Potential Impact of Agronomic Conditions on the Drainage Ability of a Short-sided Two-way Sloped Field

Abstract

It is well known that surface drainage has effects on sloped farm fields under non-tillage cropping systems; however, previous case studies have not considered the surface drainage effect of these field under tillage cropping systems yet. As for a direction of slope, some studies mainly investigated sloped farm fields which inclined to a drainage canal side (it is called as a sloped farm field inclined along a long-sided). There is a limit to extending the slope’s gradient because the difference in terms of flooding depth is larger when cultivating rice. If sloped farm fields inclined along a short-sided, the slope’s gradient was larger than when the sloped farm field inclined along the long-sided. Therefore, a short-sided two-way sloped field was here constructed using a GNSS-controlled land leveler, and its drainage effect was considered under flat ridge cropping. The result showed that, under this system, there was no effect of surface drainage on sloped field, and the effect on open ditch was larger. Therefore, when considering the introduction of a sloped field, it is essential to select appropriate cultivation methods, such as non-tillage cropping systems or techniques matching the direction of the ridge with the slope.