In natural science, subaerial (literally "under the air"), has been used since 1833,Subaerial
in the Merriam-Webster dictionary. notably in

geology Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Ea ...

and

botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

, to describe features and events occurring or formed on or near the

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

's land surface. They are thus exposed to Earth's atmosphere. This may be contrasted with '' subaqueous'' events or features located below a water surface, '' submarine'' events or features located below a sea surface, '' subterranean'' events or features located below ground, or '' subglacial'' events or features located below

glacial ice A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as ...

such as

ice sheet In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are in Antarctica and Greenland; during the Last Glacial Period at La ...

Geology

For example, a

subaerial eruption A subaerial eruption is any sort of volcanic eruption that occurs on the Earth's surface, or in the open air 'under the air', and not underwater or underground. They generally produce pyroclastic flows, lava fountains, and lava flows, which are com ...

of a

volcano A volcano is a rupture in the Crust (geology), crust of a Planet#Planetary-mass objects, planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and volcanic gas, gases to escape from a magma chamber below the surface. On Ear ...

is one that ejects material in the open but "under the air" (under the atmosphere). Subaerial

weathering Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement) ...

is weathering by rain, frost, rivers etc. The term "subaerial" may exclude processes occurring in caves. The term is often used in sedimentology.

Botany

Leaves are subaerial organs of plants.Macgregor Skene
Biology of Flowering Plants
page 2. ed. Discovery Publishing House, New Delhi, reprinted in 2006. . Some plants may have subaerial roots, either totally (

epiphytic An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

plants such as some

orchids Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

) or more commonly only partly so. The oil palm tree can grow roots into accumulations of decaying leaves on the soil surface; these roots are said to be subaerial. Epiphyte plants growing above ground that do not feed from their tree support (for example through their

haustorium In botany and mycology, a haustorium (plural haustoria) is a rootlike structure that grows into or around another structure to absorb water or nutrients. For example, in mistletoe or members of the broomrape family, the structure penetrates th ...

or feeding part having dug into the tree, such as Mistletoe)Macgregor Skene
''op. cit.''
p. 229. have subaerial roots (for example some

Ficus ''Ficus'' ( or ) is a genus of about 850 species of woody trees, shrubs, vines, epiphytes and hemiepiphytes in the family Moraceae. Collectively known as fig trees or figs, they are native throughout the tropics with a few species extendi ...

species).Macgregor Skene
''op. cit.''
p. 71. Subaerial stems are the stems that do not rise up but grow just above the ground. As a type of asexual

propagation Propagation can refer to: * Chain propagation in a chemical reaction mechanism *Crack propagation, the growth of a crack during the fracture of materials * Propaganda, non-objective information used to further an agenda * Reproduction, and other fo ...

, these subaerial

stolon In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...

s, also called ''runners'', often develop roots and leaves from their nodes."Subaerial Stem Modifications" on ''tutorvista.com''. Some pond plants have subaerial leaves as well as submerged leaves (

water plantain ''Alisma'' is a genus of flowering plants in the family Alismataceae, members of which are commonly known as water-plantains. The genus consists of aquatic plants with leaves either floating or submerged, found in a variety of still water habit ...

flowering rush ''Butomus'' is the only known genus in the plant family Butomaceae, native to Europe and Asia. It is considered invasive in some parts of the United States. Taxonomy The Butomaceae family has been recognized by most taxonomists as a plant ...

).Macgregor Skene, ''op. cit.'', p. 294.

References

{{reflist Geology terminology Botanical nomenclature

Geology

Botany

See also

References