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Soil Erosion

Soil Erosion. Bird City, Kansas. St. Francis, Kansas . San Luis Valley, Colorado. Al Asad, Iraq. The Dustbowl. How much soil is lost?. 5 Billion Tons, Billion with a “B” lost each year 3.5 Billion tons due to Water 1.5 Billion tons due to Wind. What is average loss?.

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Soil Erosion

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  1. Soil Erosion

  2. Bird City, Kansas

  3. St. Francis, Kansas

  4. San Luis Valley, Colorado

  5. Al Asad, Iraq

  6. The Dustbowl

  7. How much soil is lost? • 5 Billion Tons, Billion with a “B” lost each year • 3.5 Billion tons due to Water • 1.5 Billion tons due to Wind

  8. What is average loss? • Scientists expect to lose 5 tons per acre per year • This much can be re-captured through soil formation • Water makes up 4.8 tons lost • Wind makes up 3.3 tons lost • 8.1 tons is average • THIS IS TOO MUCH!

  9. Lasting effects of erosion • Loss of topsoil-loss of productive organisms • Organic matter gone along with N-P-K • Reduced Root Zone-less water holding capacity • Gullies make farming difficult • Pollutes lakes, streams causing harm to wildlife • Sediment fills up lakes, streams, and waterways • Loss of $$$$ due to un-productive soil Sediment fills and pollutes a lake

  10. What affects erosion • #1 Texture and Structure • The coarser the texture, the higher infiltration rate, the lower amounts of run-off • Fine particles detach easier than large particles • Silt erodes faster than sand • Good structures resist rain splash and wind lift

  11. What affects erosion • #2 Slope • Length and steepness or grade both need considered • Length accounts for volume of erosion • Grade creates water velocity • Long fields have snowball effect with wind • Little loss at the head end, piles of soil at the bottom end

  12. What affects erosion • #3 Surface Roughness • Rough soil slows water and reduces downhill flow • Tillage ridges are helpful • Tillage across slope prevents erosion, tillage with the slope promotes erosion

  13. What affects erosion • #4 Surface Cover • Surface cover reduces impact from falling water and slows down movement of water • Surface crops’ roots hold soil closely • Row crops need a foliage canopy to help protect soil

  14. What affects erosion • #5 Climate • Dry soils and dry climates promote wind erosion • The drier the soil particles the greater risk of being picked up and moved elsewhere • Dry weather promotes wind loss

  15. Types of erosion • #1 Splash Erosion • Water hits the soil and can move particles as much as 5 feet!

  16. Types of erosion • #2 Sheet erosion • A thin layer of soil is removed as a sheet. • Sheet erosion hides until topsoil is lost and subsoil is exposed. Sheet erosion exposes sub-soil in the circles

  17. Types of erosion • #3 Rill erosion • Many small channels on slopes • Running water carves out rills • Still can be filled in by tillage

  18. Types of erosion • #4 Ephemeral (e fem er al) • Large rills • Tillage won’t completely fill them in • The next rain will create gullies if not fixed

  19. Types of erosion • #5 Gully erosion • So large equipment cannot cross • Begin on steep slopes where water creates enough energy to cut large channels in the earth

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