EARTH AND SPACE SCIENCE REPORT YENN.pptx

report

1. HYDROLOGIC CYCLE Running Water: Stream Flow, Drainage, Flood

2. HYDROLOGIC CYCLE Water is constantly being cycled between the atmosphere, the ocean and land. This cycling is a very important process that helps sustain life on Earth.

3. Evaporation Condensation Precipitation Transpiration Run-off PROCESSES OF WATER CYCLE

4. STREAMFLOW The ability of a stream to erode and transport materials depends largely on its velocity. RUNNING WATER

5. CHANNEL CHARACTERISTICS - The stream channel is the course the water in a stream follows. Shape, size, and roughness • Discharge of a stream is the volume of water flowing past a certain point in a given unit of time

6. DEPOSITION  A stream’s bedload is solid material too large to carry in suspension. The capacity of a stream is the maximum load it can carry. Deposition occurs as streamflow drops below the critical settling velocity of a certain particle size. The deposits are called alluvium. Deltas are an accumulation of sediment formed where a stream enters a lake or ocean. A natural levee parallels a stream and helps to contain its waters, except during floodstage.

7. STREAM VALLEYS  Narrow Valleys A narrow V-shaped valley shows that the stream’s primary work has been downcutting toward base level.  Wide Valleys • Stream is near base level. - Downward erosion is less dominant. - Stream energy is directed from side to side. • The floodplain is the flat, low-lying portion of a stream valley subject to periodic flooding.

8. FLOOD AND FLOOD CONTROL  flood occurs when the discharge of a stream becomes so great that it exceeds the capacity of its channel and overflows its banks.  Measures to control flooding include artificial levees, flood control dams, and placing limits on floodplain development.

9. DRAINAGE The removal of excess water either from the ground surface or from the rootzone.

10.  TYPES OF DRAINAGE • Surface drainage- removal of excess water from the surface of the land • Subsurface Drainage the removal of water from the rootzone ▪ Deep open drains ▪ Pipe drains

11. ▪ Deep open drains ▪ Pipe drains The excess water from the rootzone flows into the open drains Pipe drains are buried pipes with openings through which the soil water can enter.

12. TEACHING STRATEGIES 1. Visual Presentations 2. Interactive Demonstrations 3. Interactive online games 4. Hands-On Stream Flow Models 5. Project-based learning 6. Group Discussions and debates

13. THANK YOU