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  2. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    The slow cycle operates through rocks, including volcanic and tectonic activity. There are fast and slow biogeochemical cycles. Fast cycle operate in the biosphere and slow cycles operate in rocks. Fast or biological cycles can complete within years, moving substances from atmosphere to biosphere, then back to the atmosphere.

  3. Root pressure - Wikipedia

    en.wikipedia.org/wiki/Root_pressure

    The ions accumulating interior to the endodermis in the xylem create a water potential gradient and by osmosis, water diffuses from the moist soil, across the cortex, through the endodermis and into the xylem. Root pressure can transport water and dissolved mineral nutrients from roots through the xylem to the tops of relatively short plants ...

  4. Soil-plant-atmosphere continuum - Wikipedia

    en.wikipedia.org/wiki/Soil-plant-atmosphere...

    This shows the net movement of water down its potential energy gradient, from highest water potential in the soil to lowest water potential in the air. [1] The soil-plant-atmosphere continuum (SPAC) is the pathway for water moving from soil through plants to the atmosphere. Continuum in the description highlights the continuous nature of water ...

  5. Xylem - Wikipedia

    en.wikipedia.org/wiki/Xylem

    The resulting surface tension causes a negative pressure or tension in the xylem that pulls the water from the roots and soil. [citation needed] Root pressure: If the water potential of the root cells is more negative than that of the soil, usually due to high concentrations of solute, water can move by osmosis into the root from the soil. This ...

  6. 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 ...

  7. Hydraulic redistribution - Wikipedia

    en.wikipedia.org/wiki/Hydraulic_redistribution

    Water is then pulled up from the roots to the leaves moving throughout the plant's vascular system, all facilitated by the differences in water potential in the boundary layers of the soil and the atmosphere. Therefore, the driving force for moving water through a plant is the cohesive strength of water molecules and a pressure gradient from ...

  8. Plant root exudates - Wikipedia

    en.wikipedia.org/wiki/Plant_root_exudates

    The rhizosphere is the thin area of soil immediately surrounding the root system. It is a densely populated area in which the roots compete with invading root systems of neighboring plant species for space, water, and mineral nutrients as well as form positive and negative relationships with soil-borne microorganisms such as bacteria, fungi and insects.

  9. Transpiration - Wikipedia

    en.wikipedia.org/wiki/Transpiration

    Water molecules stick together or exhibit cohesion. As a water molecule evaporates from the leaf's surface it pulls on the adjacent water molecule, creating a continuous water flow through the plant. [6] Two major factors influence the rate of water flow from the soil to the roots: the hydraulic conductivity of the soil and the magnitude of the ...