What is the relationship between distance and slope in a terrain? Distancia Reducida is the projection of any of the previous distances on a horiz...

What is the relationship between distance and slope in a terrain?

Distancia Reducida is the projection of any of the previous distances on a horizontal plane.
Vertical Distance is defined as the difference in elevation between two points.
Geometric Distance is the distance in a straight line between two points.
Natural Distance is the distance between two points following the terrain's orography.
The slope of a terrain between two points located on two consecutive contour lines is equal to the ratio between equidistance and the longitudinal distance that separates them.
The slope of the terrain is calculated by the formula P = e/D * 100, where P is the slope in %, e is the equidistance between contour lines, and D is the horizontal distance between the points considered.
To calculate the elevation of a point, it is necessary to measure the horizontal distances B-P (xp) and B-A (D) and use the formula P = e/D = yP/xP, where yP = e * xP/D. Then, the elevation of point P is determined by adding yP to the elevation of point B.
A watershed is the entire area of land that contributes to the flow of water in a river or stream.
To delimit a watershed, it is necessary to interpret the morphology or shape of the relief, identify the main river of the area and the direction of flow, and sum the tributaries or small rivers/streams that flow into that river, generating the drainage network.
The high points that are defined, generally by closed contour lines, are located, and the dividing line that must pass through them cutting orthogonally the contour lines is traced. The dividing line should never cut a river, stream, or creek.
Contour lines are separated by equal distances in the case of terrains with equal slopes. When the slope is pronounced, the separation between them is very small. In very flat terrains, the separation is wide. When the surface is rugged and irregular, the contour lines are irregular. They are perpendicular to the direction of the terrain slope, and the flow of water will be perpendicular to them. They connect points of equal elevation, so they cannot cross each other, except in caves. The tops of the mountains or the depressions of the terrain look the same, so it is convenient to record the elevation of the highest or lowest point and number the additional contour lines. They intersect at the edges of the buildings.