I Soil Conservation and Management Theme Conserving soil productivity Soil is a vital resource for production of food fiber fuel and other necessities of life II Soil conservation and management objectives Using the soil within its capabilities Maintaining the soils productive capabilities Most soil fertility is associated with clay and humus Important to Microbial activity Soil structure Permeability Water holding capacity IV Eroded soil is considered to be degraded Chemically loses chemicals and nutrients Physically lacks aggregation and structure Biologically microbial activity and carbon content decrease 1 V Why is erosion becoming more of a problem The demand for plant and animal products is increasing with time as population increases and the standard of living is raised VI What causes or initiates erosion Any that causes movement can be an initiating causative agent such as Water Wind Glaciers Animals Vehicles and Gravity landslides VII Sheet erosion Most common form of soil loss It can be uniform subtle spotty and intermittent VIII Rill erosion Shallow channel which can be removed by one pass of tillage equipment 2 IX Gully erosion Can not be removed by with one pass of farm tillage equipment X Order of decreasing severity of erosion Sheet rill megarill ephemeral gullies valleys 3 XI Tolerable soil loss In Illinois 11 mt ha 5 tons ac is the maximum acceptable soil loss XII Normal erosion XIII Accelerated erosion Caused by man s activities Removal of vegetation leaves soil less protected from the detaching action of running water Can be 10 to 100 times greater than normal erosion Rate of soil loss under natural vegetation Soil is at equilibrium Rate of soil formation is approximately equal to the rate of soil loss XIV Erosion is a historical problem Since the dawn of civilization erosion has been a problem Cultivated fields overgrazed pastures and cut over forest lands have always suffered from erosion 4 5 XV Eroded soil becomes a sediment that Pollutes streams Covers bottomlands Sometimes becomes so thick that it buries both fields and cities XV Obstacles to conservation Economic Aesthetic and cultural Insecurity and uncertainty Ignorance and apathy 6 XVII Conservation methods Requires the use of the land within its capabilities Assumes that soil and water conservation are interrelated XVIII Choosing conservation practices Soil properties Are basic to conservation Influence the selection of erosion control methods Include soil topography gradient length shape and aspect depth permeability texture structure and fertility 7
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