What factor primarily dictates the steepness of a slope?

The steepness of a slope is fundamentally determined by the slope gradient, which is a measure of the angle of the slope relative to the horizontal ground. It is often expressed as a percentage or a ratio, indicating how much vertical rise occurs for a certain horizontal distance. A higher gradient means a steeper slope, while a lower gradient corresponds to a more gentle slope.

Understanding slope gradient is crucial in fields such as civil engineering, environmental science, and geography, as it directly influences various factors including erosion rates, water runoff, and land-use planning. For example, steeper slopes are generally more susceptible to erosion and landslides, whereas flatter slopes may retain water better and support different types of vegetation.

While other factors like rainfall, vegetation, and temperature can influence slope stability and soil condition, the intrinsic characteristic that defines how steep a slope is remains the slope gradient itself.