Bellringer: How is ROCK broken up and changed? By Weathering at earth’s surface How is SOIL moved? By Erosion: the physical removal and transport of rock material by water, wind or ice.
How soil is eroded? Rain loosens soil Flowing water across the surface carries away the dislodged soil particles (sheet erosion)
Rates of erosion depend on Soil characteristics Climate: wet, dry windy Slope: steep Type and amount of vegetation / trees Human activity: farming, logging, construction
Transporting loose soil by WIND What would have prevented this??
North American Prairie Deep roots held the soil
What are some measures that can be done to prevent or slow the rate of erosion? Plant ‘cover crops’ (hay) Plant trees as windbreak and roots hold soil . Contour plowing for crops
How can we slow the rate of erosion? Terrace planting of crops Stone walls
How can we slow the rate of erosion? Rip rap bioswale
Methods to prevent mass wasting erosion Examples of erosion control methods include: buffer strip crop rotation conservation tillage contour plowing cover crops fiber rolls gabions level spreaders mulching perennial crops reforestation riprap strip farming sand fence waterway (bioswale) terracing wattle (construction) windbreaks