Rivers Flashcards
(14 cards)
What is the source of a river, and how does it influence the river’s characteristics?
The source is where a river begins, usually in highland areas. It determines the river’s initial speed and direction.
Define the term “tributary” and explain its role in a river system.
A tributary is a smaller river or stream that flows into a larger river, increasing its water volume.
What are the three main stages of a river, and how do they differ?
Upper course (steep, fast-flowing, erosion dominates), middle course (meanders, balanced erosion and deposition), lower course (wide, slow, deposition dominates).
Describe how a meander forms and why rivers develop them over time.
Meanders form due to erosion on the outer bend and deposition on the inner bend, causing the river to curve over time.
What is the difference between erosion and deposition in a river system?
Erosion wears away land and carries sediment; deposition drops sediment, forming new land features like deltas.
What is a river delta, and how does it form?
A delta is a landform at a river’s mouth, formed by sediment deposition as the river slows down when entering a larger body of water.
What is the difference between a river’s bedload and suspended load?
Bedload consists of larger particles that roll or bounce along the riverbed, while suspended load includes smaller particles carried within the water.
What is the role of vegetation in preventing riverbank erosion?
Vegetation stabilizes riverbanks by holding soil together with roots, reducing the impact of flowing water.
What is a watershed, and why is it important?
A watershed is an area of land where all the water drains into a specific river or stream. It helps manage water flow and ecosystems
How does hydraulic action contribute to river erosion?
Hydraulic action occurs when water forces air into cracks in rocks, breaking them apart over time.
What is a river’s load, and how is it transported?
A river’s load consists of materials it carries, transported by traction (rolling), saltation (bouncing), suspension, and solution.
How do waterfalls develop in a river’s upper course?
Waterfalls form where hard rock overlays soft rock, with erosion creating a steep drop.
What is a flood hydrograph, and what does it show?
A flood hydrograph is a graph showing changes in river discharge over time, helping predict flooding risks.
How does river rejuvenation occur?
Rejuvenation happens when a river’s energy increases due to changes in sea level or land uplift, causing deeper erosion.
