Final answer:
Contour farming is the practice of plowing and planting across the changing slope of the land to help retain water and reduce soil erosion.
Step-by-step explanation:
The practice of plowing and planting across the changing slope of the land, rather than in straight lines, to help retain water and reduce soil erosion is called contour farming. In contour farming, the crops are planted perpendicular to the slope, following the contour lines of the land. This method helps slow down the flow of water, allowing it to soak into the soil and reduce runoff. It also helps prevent soil erosion by reducing the speed at which water moves across the slope, preventing the washing away of topsoil.
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