Which combination of slope characteristics enhances erosion potential?

The combination of long and steep slope characteristics significantly enhances erosion potential for several reasons.

First, the steepness of a slope increases gravitational forces acting on soil and sediment. When rainwater falls, it travels more quickly down a steep slope, reducing the time for water to infiltrate the soil. This causes surface runoff to increase, which can lead to erosion as the water dislodges soil particles and carries them away.

Additionally, longer slopes provide a greater distance for water to flow, which can further amplify the intensity of the runoff. As water accumulates and flows down a long steep slope, it gains energy, which increases its ability to erode soil and sediment from the surface.

In contrast, combinations such as short and flat, short and steep, or flat and even do not exhibit the same potential for erosion due to limited gravitational force on gentler grades and reduced runoff dynamics on shorter lengths. Flat surfaces allow water to spread out and infiltrate the soil rather than flowing and eroding it away.