MadSci Network: Environment & Ecology |
Dear Nikki, Grass is very important in preventing soil from being washed away. When rain drops hit bare soil they can move down hill quickly. The faster the water is moving, the more soil it can carry away. If there is grass it slows the water down, because the water has to go around grass blades. The roots of grass are also important. The roots are like lots of little nets in the ground helping to hold the soil in place. Soil being held by roots is much harder to wash away than soil with no roots. Grass is not the only thing that prevents erosion. All plants help prevent soil erosion. Next time you're on a long car ride try to look for bare soil next to soil that has things growing on it. You might notice that the bare soil has been washed away. You might see small channels where water runs. A good place to see the differences is a hill. Tarrah
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