Subaerial

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The term subaerial (literally "under the air"), first used in 1833,[1] is mainly used in natural science, notably in geology and botany, to describe events or features that are formed, located or taking place immediately on or near the Earth's land surface.[1] They are thus exposed to Earth's atmosphere. This may be contrasted with subaqueous[2] events or features — located below a water surface, submarine events or features — located below a sea surface, or subglacial ones — located below glacial ice such as ice sheets.

Geology[edit]

For example, a subaerial eruption of a volcano is one that ejects material in the open but "under the air" (under the atmosphere). Subaerial weathering is weathering by rain, frost, rivers etc.

The term "subaerial" may exclude processes occurring in caves.[citation needed]

The term is often used in sedimentology.

Botany[edit]

Leaves are subaerial organs of plants.[3]

Some plants may have subaerial roots,[1] either totally (epiphytic plants such as some orchids) or more commonly only partly so. The oil palm tree can grow roots in loose leaves partly decayed on the ground's surface; these roots are said to be subaerial.[4] Epiphyte plants growing above ground that do not feed from their tree support (for example through their haustorium or feeding part having dug into the tree, such as Mistletoe)[5] have subaerial roots (for example some Ficus species).[6]

Subaerial stems are the stems that do not rise up but grow just above the ground. As a type of asexual propagation, these subaerial stolons, also called runners, often develop roots and leaves from their nodes.[7]

Some pond plants have subaerial leaves as well as their submerged ones (water plantain, flowering rush,...).[8]

See also[edit]

References[edit]

  1. ^ a b c Subaerial in the Merriam-Webster dictionary.
  2. ^ Robert L. Bates, Julia A. Jackson, Dictionary of Geological Terms AGI (1984)
  3. ^ Macgregor Skene. Biology of Flowering Plants, page 2. ed. Discovery Publishing House, New Delhi, reprinted in 2006. ISBN 81-7141-205-X.
  4. ^ R.H.V. Corley & P.B.H. Tinker. The Oil Palm, 4th edition, page 37. Blackwell Science, 2003 (three eds. in 1967, 1977 and 1988).
  5. ^ Macgregor Skene, op. cit., p. 229.
  6. ^ Macgregor Skene, op. cit., p. 71.
  7. ^ Subaerial Stem Modifications on tutorvista.com.
  8. ^ Macgregor Skene, op. cit., p. 294.