Energy of River

Mere som dette

tropical rainforest

af wei da

Rivers

af Wong Yien

Dynamics

af Nicholas Casson

Chapter 3, Natural vegetation

af Wang ShiMei

Energy of River

Volume of River

Climate

Low rainfall will have lower volume of water.

High rainfall will have higher volume of water.

Permeability of rocks

Low permeabilty decreases infiltration and increases surface runoff, hence volume of water is high.

High permeability increases infiltration and decreases surface runoff, hence volume of water is low.

Presence of vegetation

Sparse vegetation leads to high surface runoff, thus increases the amount of water.

Abundant vegetation leads to low surface runoff, thus reduces the amount of water.

Size of drainage basin

Large drainage basin results in large volume of water.

Small drainage basin results in small volume of water.

Speed of Flow

Wetted Perimeter

Smaller wetted perimeter causes the speed to be high because there is less friction.

Larger wetted perimeter causes the speed to be low because there is a lot of friction.

Roughness of channel

Smooth channel increases the speed because of lower friction.

Rough channel reduces the speed because of higher friction.

Gradient of channel

Steep gredient causes the speed of river to be high.

Gentle gradient causes the speed of river to be low.