Stream Gradient
A stream is any flow of water, and water flows from higher
elevation to lower elevation on the earth's surface. As it makes
its way across the land surface back to the ocean, it may
considerably alter the surface over which it flows. RUNNING
WATER, a stream, is one of the AGENTS of erosion. The processes
associated with running water are referred to as FLUVIAL. In
previous activities, we looked at stream systems and their
drainage basins, divides, and the tributaries. We examined the
relationship between discharge, velocity, and depth.
Another relationship to consider is that of gradient. Gradient is
the slope of the stream and is measured by the difference in
elevation between two points on a stream divided by the distance
between the two points that the water actually flows. Gradient is
usually expressed in feet per mile of meters per kilometer. The
phrase RISE OVER THE RUN is the "shorthand" of the
formula. See the illustration below. Gradient looks at how far
the water drops over the distance the water actually flows. The
gradient influences the velocity of the stream. The steeper the
gradient, the higher will be the velocity if all other factors
are held constant.
Continue with the
lesson