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  2. Soil retrogression and degradation - Wikipedia

    en.wikipedia.org/wiki/Soil_retrogression_and...

    This reduces the food security, which many countries facing soil degradation already do not have. [8] Slight degradation refers to land where yield potential has been reduced by 10%, moderate degradation refers to a yield decrease of 10–50%. Severely degraded soils have lost more than 50% of their potential.

  3. Cell theory - Wikipedia

    en.wikipedia.org/wiki/Cell_theory

    From these conclusions about plants and animals, two of the three tenets of cell theory were postulated. 1. All living organisms are composed of one or more cells 2. The cell is the most basic unit of life. Schleiden's theory of free cell formation through crystallization was refuted in the 1850s by Robert Remak, Rudolf Virchow, and Albert ...

  4. Soil conservation - Wikipedia

    en.wikipedia.org/wiki/Soil_conservation

    The terraces form a series of steps each at a higher level than the previous. Terraces are protected from erosion by other soil barriers. Terraced farming is more common on small farms. This involves creating a series of flat terraced levels on a sloping field.

  5. Land degradation - Wikipedia

    en.wikipedia.org/wiki/Land_degradation

    Overgrazing by livestock can lead to land degradation. Land degradation is a process where land becomes less healthy and productive due to a combination of human activities or natural conditions. The causes for land degradation are numerous and complex. [1] Human activities are often the main cause, such as unsustainable land management practices.

  6. Environmental degradation - Wikipedia

    en.wikipedia.org/wiki/Environmental_degradation

    One major component of environmental degradation is the depletion of the resource of fresh water on Earth. [23] Approximately only 2.5% of all of the water on Earth is fresh water , with the rest being salt water . 69% of fresh water is frozen in ice caps located on Antarctica and Greenland , so only 30% of the 2.5% of fresh water is available ...

  7. Soil erosion - Wikipedia

    en.wikipedia.org/wiki/Soil_erosion

    Wind erosion is a major geomorphological force, especially in arid and semi-arid regions. It is also a major source of land degradation, evaporation, desertification, harmful airborne dust, and crop damage—especially after being increased far above natural rates by human activities such as deforestation, urbanization, and agriculture. [22] [23]

  8. Phytoremediation - Wikipedia

    en.wikipedia.org/wiki/Phytoremediation

    Phytoremediation technologies use living plants to clean up soil, air and water contaminated with hazardous contaminants. [1] It is defined as "the use of green plants and the associated microorganisms, along with proper soil amendments and agronomic techniques to either contain, remove or render toxic environmental contaminants harmless". [2]

  9. Desertification - Wikipedia

    en.wikipedia.org/wiki/Desertification

    Desertification is a gradual process of increased soil aridity.Desertification has been defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities."