River Course Characteristics and Water Movement

This page delves deeper into the characteristics of different river courses and the movement of water within a drainage basin. It highlights the differences between upper and lower river courses and explains various water transfer processes.

The upper course of a river is described as relatively straight with bends around obstacles. The middle course becomes more winding, while the lower course features large bends. These differences reflect changes in the river's energy and erosional processes along its length.

Water transfer processes within the drainage basin system are explained in detail:

1. Surface runoff: Water movement across the Earth's surface, forming streams and rivers.
2. Infiltration: Water soaking into the soil.
3. Percolation: Water movement from soil into underlying rock.
4. Groundwater flow: Slow water movement through soil and rocks, eventually returning to the sea.
5. Throughflow: Downhill water movement through soil.

Highlight: The shape and characteristics of a river channel change significantly from the upper to the lower course, reflecting changes in water volume, velocity, and erosional power.

Vocabulary: Percolation - The downward movement of water through soil and rock layers.

The page also introduces the concept of river discharge, which is the amount of water passing a certain point at a given time, measured in cubic meters per second (cumecs).

Comparing River Courses: Upper, Middle, and Lower

This final page focuses on comparing the characteristics of upper, middle, and lower river courses, emphasizing the differences between upper and lower river courses. It provides a more detailed look at how river channels change along their length.

Key comparisons include:

1. Channel shape: Upper courses are relatively straight with bends around obstacles, middle courses become more winding, and lower courses feature large meanders.
2. Width: Generally increases from upper to lower course as more tributaries join the main river.
3. Depth: Typically increases downstream as the river carries more water.
4. Gradient: Steeper in the upper course, becoming gradually less steep in the middle and lower courses.
5. Discharge: Increases downstream as more water enters the river system.
6. Energy: Generally decreases from upper to lower course, affecting erosional and depositional processes.

Highlight: The changes in river characteristics from upper to lower courses reflect the river's changing ability to erode, transport, and deposit sediment along its journey.

Vocabulary: Gradient - The slope or steepness of a river's course.

The page also mentions that the load (sediment) carried by the river changes along its course, reflecting changes in the river's energy and capacity to transport material.

This comparison helps to consolidate understanding of how rivers change from source to mouth, tying together the concepts of drainage basins, the water cycle, and river geomorphology.