Thursday, January 31, 2008
Fun@Work
"Room for Improvement"
Wednesday, January 30, 2008
Tuesday, January 29, 2008
Fun@Work
Being cheeky, I told her it would be coming next week.
Chinese New Year- The Year of the Rat
Monday, January 28, 2008
Natural Vegetation- What is Natural Vegetation?
What is Natural Vegetation?
Natural vegetation refers to plants that grow naturally in a place with little or no human interference.
Why is Natural Vegetation important?
Natural Vegetation plays an important role in a forest ecosystem by providing food and shelter for the animals and native people that live in the forest.
Sunday, January 27, 2008
Fun@Work
When he was asked why, he explained that the time table read "Home Period" so he stayed at home.
Poor boy, since he's in the Normal Academic stream. I believe his friends will remember this for a very long time...
*Home period is time dedicated in the time table for form teachers to interact and perform administrative duties with their class.
Saturday, January 26, 2008
Friday, January 25, 2008
River Features- Ox-bow Lake
The following webpage shows an animation of how an oxbow lake is formed.
http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21606
Thursday, January 24, 2008
River Processes
There are 3 river processes that occur as the river flows along its course.
1) Erosion
occurs when rocks and other materials are broken into smaller pieces and moved downstream by the energy of the river.
The four processes of erosion are:
- Hydraulic action where fast-moving water loosens and dislodges the rocks and soil from river bed and banks.
- Corrasion where rock fragments that are dragged along by the flow of the river, grind against the river bed and banks.
- Attrition where eroded materials in the river constantly collide against each other and break down into smaller pieces.
- Solution where minerals in the rock dissolve in the carbonic acid in the river due to acid rain.
To remember:
" I was a piece of rock by the river bank, broken off by hydraulic action. I was carried by the river causing corrasion as I erode the river bed and banks. I collide against the other rocks, resulting in attrition. I’m going to be dissolved in solution as there’s carbonic acid in the water. "
(By student: Hot Chicks Affect Success)
2) Transportation
occurs when materials are carried downstream by the energy of the river.
The four processes of transportation are:
- Traction where the larger size materials are rolled and slided along the river bed. (e.g boulders and gravel)
- Saltation where materals are transported downstream in a series of bouncing action. (e.g. coarse sand)
- Suspension where fine particles are carried along in the river without touching the river bed. (e.g. silt and clay)
- Solution where the river transport dissolved materials downstream. (e.g. calcium carbonate)
The following webpage shows an animation of how the river transports its load.
http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21393
To remember:
" There was a tractor (traction) bringing soil to the construction site. However the salt (saltation) content of the soil is too high. The driver got a suspension and has to think of a solution as he lost his rice bowl. "
(By student: Think Some Sexy Stuff)
3) Deposition
occurs when the river puts down or deposits its load due to insufficient energy.
Energy of the River
The energy of the river is determined by 2 factors- speed of flow and volume of water. Therefore, when the speed of flow and the volume of water is high, the energy of the river is also high. We say that there is a positive relationship between energy of river and the speed of flow and the volume of water that the river is carrying.
There are 3 factors affecting the speed of the river. (GRoW)
1) Gradient of channel
Rivers flow downhill from a height due to gravity. Therefore, a steep gradient will cause the speed of the river to be fast.
2) Roughness of channel
A smooth channel without obstacles like rocks and boulders will increase the speed of the river.
3) Wetted perimeter
The lesser the water that contact the river channel, the higher the speed of flow due to less friction.
There are 4 factors affecting the volume of water in the river. (SPCPetrol)
1) Size of Drainage Basin
The larger the drainage basin, the higher the volume of water of the river.
2) Presence of Vegetation
More vegetation will result in higher interception and lower runoff, resulting in lower volume of water. Vegetation will also delay the amount of water that reaches the river in a short time, preventing floods.
3) Climate
If the rainfall is high, the river will have a higher volume of water.
Climate will also determine the amount of vegetation in the river vicinity.
4) Permeability of Rocks
High premeability will result in low volume of water due to decrease in runoff.
3 Courses of the River
At the upper course of the river, the gradient is very steep and the river channel is narrow and shallow. The amount of water is low and the speed of the water is very fast. Due to the vertical erosion, the river channel is of a steep V shape.
At the middle course, the gradient of the river is not as steep as the upper course. The speed of the river reduces compared to the upper course. The river channel is wider and deeper as the tributaries join the main river. The river channel is U-shaped.
At the lower course, the gradient of the river is almost flat. The speed of the river is the slowest at this point and the volume of water is the highest of all three courses.The river channel is also the widest and deepest, taking a wide U-shape.
Wednesday, January 23, 2008
Textbook and Objectives of Blog
You may ask why would it be necessary to read this blog if you have the textbook and many other texts. Well, the objectives of this blog are really to simplify the information for easier understanding and provide drawable diagrams for usage during exams so as to promote independent learning. Examples of questions and suggested answers will be provided for self practice and revision. Teachers may find teaching resources while students will be able to find revision notes to prepare for their examination.
I do not deny the possibility of moving this blog to a private site if the response is good. However, it would take time to develop this blog into a comprehensive one.
Welcome
Welcome to my blog on GCE 'O' Level Geography Elective (Syllabus 2190/2).
In this blog, you will find notes, diagrams, pictures, questions, answers and links to relevant websites relating to the preparation for GCE 'O' Level Geography Elective Written Examination.
This blog may comprise of information gathered through various textbooks, students' work and many other contributions. All diagrams and animations found on this blog are the creations of the author.
The 4 main topics covered are:
- Rivers & Coasts
- Natural Vegetation
- Geography of Food
- Development
Tip:
1) Search by the topic and area that you wish to look for. (E.g. river waterfall)