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  2. Hydroponics - Wikipedia

    en.wikipedia.org/wiki/Hydroponics

    He found that plants in less-pure water sources grew better than plants in distilled water. By 1842, a list of nine elements believed to be essential for plant growth had been compiled, and the discoveries of German botanists Julius von Sachs and Wilhelm Knop , in the years 1859–1875, resulted in a development of the technique of soilless ...

  3. Soil acidification - Wikipedia

    en.wikipedia.org/wiki/Soil_acidification

    Impacts of acidic water and Soil acidification on plants could be minor or in most cases major. In minor cases which do not result in fatality of plant life include; less-sensitive plants to acidic conditions and or less potent acid rain. Also in minor cases the plant will eventually die due to the acidic water lowering the plants natural pH.

  4. Plant nutrients in soil - Wikipedia

    en.wikipedia.org/wiki/Plant_nutrients_in_soil

    Nutrients in the soil are taken up by the plant through its roots, and in particular its root hairs.To be taken up by a plant, a nutrient element must be located near the root surface; however, the supply of nutrients in contact with the root is rapidly depleted within a distance of ca. 2 mm. [14] There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought ...

  5. Aquaponics - Wikipedia

    en.wikipedia.org/wiki/Aquaponics

    Some authors have reported 90% less water usage through aquaponics compared to conventional commercial fish and crop production systems. [6] Water is added to the system only to replace losses due to plant absorption and transpiration, evaporation, overflow from rainfall, and removal of solid wastes. Consequently, aquaponics uses about 2% of ...

  6. Waterlogging (agriculture) - Wikipedia

    en.wikipedia.org/wiki/Waterlogging_(agriculture)

    All plants, including crop, require air (specifically, oxygen) to respire, produce energy, and keep their cells alive. In agriculture, waterlogging typically blocks air from getting to the roots. [3] With the exception of rice (Oryza sativa), [4] [5] most crops like maize and potato, [6] [7] [8] are therefore

  7. Soil pH - Wikipedia

    en.wikipedia.org/wiki/Soil_pH

    In soils, it is measured in a slurry of soil mixed with water (or a salt solution, such as 0.01 M CaCl 2), and normally falls between 3 and 10, with 7 being neutral. Acid soils have a pH below 7 and alkaline soils have a pH above 7. Ultra-acidic soils (pH < 3.5) and very strongly alkaline soils (pH > 9) are rare. [2] [3]

  8. Photosynthetic efficiency - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_efficiency

    The following is a breakdown of the energetics of the photosynthesis process from Photosynthesis by Hall and Rao: [6]. Starting with the solar spectrum falling on a leaf, 47% lost due to photons outside the 400–700 nm active range (chlorophyll uses photons between 400 and 700 nm, extracting the energy of one 700 nm photon from each one)

  9. Liebig's law of the minimum - Wikipedia

    en.wikipedia.org/wiki/Liebig's_law_of_the_minimum

    A market-based theory depends on proper pricing. Where resources such as clean air and water are not accounted for, there will be a "market failure". These failures may be addressed with Pigovian taxes and subsidies, such as a carbon tax. While the theory of the law of substitutability is a useful rule of thumb, some resources may be so ...