Flashcards in Paper 2 Jan 2017 Deck (22):
What is abrasion?
Sand and pebbles are dragged along the riverbed, wearing it away
What is attrition?
Rocks wear each other away as they knock together
What is hydraulic action?
Fast flowing water is forces into cracks, breaking up the bank over time
What is a solution?
Alkali rocks e.g. limestone are dissolved in acid rainwater
What is saltation?
Small stones are picked up and then dropped again along the riverbed
What is a suspension?
Tiny particles of sediment are carried in the river's current
What is traction?
Large stones are dragged along the river bed
What is the Three Gorges Dam?
Mega-dam located on Yangtze River in Central China
How long did the Three Gorges Dam take to build?
Took 15 years to build
Why was the Three Gorges Dam built?
Built in response to seasonal flooding along Yangtze River that has killed hundred of thousands of people
What was the 1998 Flood along the Yangtze River?
- Killed over 3500 people
- Left 13million people homeless
- Billions of dollars damage
How much did the Three Gorges Dam cost to build?
180 billion Chinese yen
How long will it take for the Three Gorges Dam to pay for itself?
It will take a decade to pay for itself by generating electricity
Who was the Three Gorges Dam funded by?
The China Development Bank
How does the Three Gorges Dam aid navigability and increase trade capacity?
The dam aids the navigability of the Yangtze by making it slower and deeper, increasing trade capacity
How has the Three Gorges Dam reduced the money spent on mining and importing coal?
Reducing the dependency on coal
How has the Three Gorges Dam reduced agricultural yield?
Lack of annual flooding reduces fertility of farmland on Yangtze's floodplain, reducing agricultural yield
How many people were required to leave their homes because of the Three Gorges Dam and what was the impact?
1.2 million +
Those who refused were forcibly removed
People relocated to cities where they struggled to find employment
New homes increased living standards
How many cities and villages did the reservoir of the Three Gorges Dam flood?
The reservoir flooded 13 cities and hundreds of villages, which were home to cultural relics and family burial ground
What was the result of sediment being blocked behind the Three Gorges Dam?
Yangtze River transports lots of sediment
Now blocked behind dam
Result in gradual destruction of Yangtze's delta and increased erosion downstream
Why is a reduction in biodiversity a consequence of blocked sediment behind the Three Gorges Dam?
Blocked sediment alters the chemical composition of water upstream from dam.
Leading to a reduction in biodiversity and the potential extinctions of some species