Important note for Indonesian teachers: nature disaster= disaster happened in our environment, related with nature activity and + or human/other activity (not only by nature). The means of "nature" just to show that it happened in our environment, but not to strictly limit the cause only by nature / non human factors.
Hello again teachers. This time I try to build a module that fix into nature disaster topics. For the first module I took "flood" topic cos it happened now in my town Bogor. Jakarta, the capital city of Indonesia also strike by the flood in 2006 and it really bad.
To talk about nature disaster: flood and land slide, I made two separate experiments to show kids the process of flood. I believe lecturing is not enough and great discussion only occurred when the participants feel/see/touch what really happened. I suggest that we also can use movie clip as a media when this experiments cannot be done.
1. A model that can describe land, made from sand / soil/other matter. Different type of soil is needed if we want to explain more about relation between soil type and porosity.
2. Water and shower
3. A model like number 1, but this time use and mix the model with cotton or water absorber matter (use tissue paper for instance)
Then start the experiments. You can shower water into the model to see what happened. A "bald" land (made from only sand / soil will be vulnerable for a slide.
For the second model (that also contain water absorber matter in the surface), the water will run more slowly. If we use more cotton and cover it into all surfaces, the matter will absorb most of the water.
A guide for teachers:
1. A flood happened when the water intensity (from the rain) is much bigger than the land capacity to absorb the water. Land always need time to absorb water, regarding its porosity so when there are no tree, humus, or a lake that slow or absorb water, a big part of water will run directly into the river / low land and cause a flood. Sometimes it take not only water but also log, garbage and make it more even dangerous specially in populated /low land area.
2. Land slide is also related with soil porosity and water. Some plants can protect the land by holding soil with their root. Their leaves and branch also protect the land from direct intensity of the sun and rain, and keep the land humidity.
3. Flood and land slide also related with human activity. Mention that landfill, mining, deforestation, and other development can effect land stabilization and capacity
Ask children about the flood:
- According to them, why flood and land slide happened in their first experiment? Is the "disaster" intensity decrease when they use water absorber matter in their second experiments?
- Ask them (or you tell them) if there any place near your environment that have flood and land slide problem. Encourage them to tell the story about what happened and why this was happened?
- In our environment, what kind of water absorber / reservoir is present around us? (hope they can tell us about forest, lake, garden, etc). Don't forget to ask them is the quality and quantity of this place is enough to protect our place from flood and land slide?
- What can we do to protect our area from flood and land slide? Give them clue that a small action is also benefit the environment, while they also can tell about their plan when they already a grown up... ^_^
Picture taken from google images