The most recognized land-forming structure is the bench terrace that is used to grow crops on very steep slopes in the mountainous regions of the world. Embankments are used to store water to grow crops, in particular rice, and to prevent runoff and soil erosion.
On less steep lands, contour and parallel terraces are constructed to intercept runoff and convey it across the slope through graded channels into an integrated system of grassed waterways, water and sediment control basins, drop structures, subsurface drainage, and/or protected outlets. Contour terraces follow the contour of the land. Parallel terraces are constructed parallel to each other and, where possible, in the direction of field operations, but they do not strictly follow the contour of the land. Parallel terraces require a more complex system ofoutlets as the land undulates along the terrace.
The earthen embankments and channels of contour and parallel terraces are constructed with earth-moving equipment such as bulldozers and scrapers. Lighter equipment such as the moldboard plow can be used to maintain these structures, but they can also be used to establish them. The two-way or rollover moldboard plow can be used to progressively move the topsoil in any desired direction, and can be used to move soil away from the channel and toward the embankment to maintain its form, countering any leveling caused by other tillage practices.
Was this article helpful?