1. Civilization depends on soil and water resources for food production.

    • Soil resources were and are an important factor in shaping history and development. Survival of humans and animals is dependent on light, water, air and soil.

    • Cultivation of plants for food allowed humans to convert from a nomadic hunting and gathering lifestyle to a more settled existence.

    • Mesopotamia between the Tigris and Euphrates River in what is now Iraq shows evidence of very early civilization. Writings dating to 2500 B.C. mention fertility of the land. Fertility was due to annual flooding of the land, and a system of canals were built for irrigation of crops.

  2. Soils are a vital resource that are a part of the natural environment.

    1. Necessary for the production of food and fiber

      1. Soil provides water, oxygen, nutrients, and support (anchorage) for plants

        1. Natural ecosystems- Soil affects water, nutrients, gases (carbon dioxide and oxygen), temperature, carbon cycling.

        2. Crops-food, fiber, and fuel

        3. Forestry-trees-fuel, fiber, building materials

        4. Horticulture-landscape, ornamentals, turf

        5. Grazing land- Livestock production

    2. Disposal and treatment of wastes. Provides habitat for decomposer organisms that cycle carbon and mineral nutrients.

      1. Animal wastes from farms

      2. Domestic wastes from homes- soils are important for septic tank drainage fields.

      3. Industrial wastes

    3. Physical support, construction materials, and recreation

      1. Support for building foundations

      2. Construction materials for roads and dams

      3. Parks, natural areas (esthetic value), athletic and recreational fields

    4. Ion exchange properties are important in retaining nutrients and providing a buffer to resist change in pH.

  3. Why Study Soils?

    1. To learn how to conserve and utilize soils properly. Poorly managed soils lose up to 30 tons/acre/year to erosion

    2. To understand how soil chemical and physical properties affect various uses of soils

    3. To understand soil variability

    4. To understand how soil properties can be modified to improve their quality for a particular use

  4. Soil Quality

    1. The capacity of a soil to provide the needed functions for human or natural ecosystems sustained over a long period of time.

    2. Factors resulting in soil degradation

      1. Erosion

      2. Pollution

      3. Desertification

      4. Soil Chemistry

      5. Increased Salinity

      6. Loss of organic matter

    3. Best Management Practices help sustain soil quality.