View source for Epiphyte

{{Short description|Non-parasitic surface organism that grows upon another plant but is not nourished by it}}
[[File:Tillandsia bourgaei.jpg|thumb|right|''[[Tillandsia bourgaei]]'' growing on an oak tree in Mexico]]
An '''epiphyte''' is a plant or plant-like organism that grows on the surface of another 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 [[Phorophyte|phorophytes]]. Epiphytes take part in [[nutrient cycle]]s and add to both the diversity and biomass of the ecosystem in which they occur, like any other organism. They are an important source of food for many species. Typically, the older parts of a plant will have more epiphytes growing on them. Epiphytes differ from [[Parasitism|parasites]] in that they grow on other plants for physical support and do not necessarily affect the host negatively. An organism that grows on another organism that is not a plant may be called an [[epibiont]].<ref>{{cite book|author1=Hickey, M.|title=The Cambridge Illustrated Glossary of Botanical Terms|author2=King, C.|publisher=Cambridge University Press|year=2001}}</ref> Epiphytes are usually found in the temperate zone (e.g., many [[moss]]es, [[Marchantiophyta|liverworts]], [[lichen]]s, and [[alga]]e) or in the tropics (e.g., many [[fern]]s, [[Cactus|cacti]], [[orchid]]s, and [[bromeliad]]s).<ref>''Webster's Third New International Dictionary of the English Language, Unabridged''. (1976). Vol. I, p. 764. Encyclopædia Britannica, Inc. Chicago.</ref> Epiphyte species make good [[houseplant]]s due to their minimal water and soil requirements.<ref>{{cite news|last1=Dabbs|first1=Amy|date=19 December 2014|title=Epiphytes are easy to grow Houseplants get water from air|work=Post and Courier|url=http://www.postandcourier.com/features/home_and_garden/epiphytes-are-easy-to-grow-houseplants-get-water-from-air/article_3b5b195f-ab48-5b1c-92a7-c3d7cc9de4b8.html|access-date=15 December 2016}}</ref> Epiphytes provide a rich and diverse habitat for other organisms including animals, fungi, bacteria, and [[Mycetozoa|myxomycetes]].<ref>{{cite journal|author1=Sydney E. Everhart|author2=Joseph S. Ely|author3=Harold W. Keller|year=2009|title=Evaluation of tree canopy epiphytes and bark characteristics associated with the presence of corticolous myxomycetes|url=http://people.oregonstate.edu/~everhars/CanopyEpiphytes_Botany2009.pdf|url-status=dead|journal=Botany|volume=87|issue=5|pages=509–517|doi=10.1139/b09-027|archive-url=https://web.archive.org/web/20130926011902/http://people.oregonstate.edu/~everhars/CanopyEpiphytes_Botany2009.pdf|archive-date=2013-09-26}}</ref>
Epiphyte is one of the subdivisions of the [[Raunkiær plant life-form|Raunkiær system]].
The term ''epiphytic'' derives from the Greek {{transliteration|grc|epi-}} (meaning 'upon') and {{transliteration|grc|phyton}} (meaning 'plant'). Epiphytic plants are sometimes called "air plants" because they do not root in soil. However, that term is inaccurate, as there are many aquatic species of [[algae]] that are epiphytes on other aquatic plants (seaweeds or aquatic [[angiosperms]]).
==Terrestrial epiphytes==
The best-known epiphytic plants include [[moss]]es, [[orchid]]s, and [[bromeliad]]s such as [[Spanish moss]] (of the genus ''[[Tillandsia]]''), but epiphytes may be found in every major group of the plant kingdom. Eighty-nine percent of (or about 24,000) terrestrial epiphyte species are [[flowering plant]]s. The second largest group are the [[leptosporangiate fern]]s, with about 2,800 species (10% of epiphytes). About one-third of all fern species are epiphytes.<ref>Hogan, C Michael, 2010. [http://www.eoearth.org/article/Fern ''Fern''. Encyclopedia of Earth. National council for Science and the Environment] {{webarchive |url=https://web.archive.org/web/20111109071540/http://www.eoearth.org/article/Fern |date=November 9, 2011 }}. Washington, DC</ref> The third largest group is [[clubmoss]]es, with 190 species, followed by a handful of species in each of the [[spikemoss]]es, other ferns, [[Gnetophyta|Gnetales]], and [[cycad]]s.<ref>{{citation | url = http://dukespace.lib.duke.edu/dspace/bitstream/10161/181/1/D_Schuettpelz_Eric_a_052007.pdf | title = The evolution and diversification of epiphytic ferns | author = Schuettpelz, Eric | year = 2007 | publisher = Duke University PhD thesis | access-date = 2009-12-11 | archive-date = 2010-06-20 | archive-url = https://web.archive.org/web/20100620022844/http://dukespace.lib.duke.edu/dspace/bitstream/10161/181/1/D_Schuettpelz_Eric_a_052007.pdf | url-status = dead }}</ref>
The first important monograph on epiphytic [[plant ecology]] was written by [[Andreas Franz Wilhelm Schimper|A. F. W. Schimper]] ({{lang|de|Die epiphytische Vegetation Amerikas}}, 1888). Assemblages of large epiphytes occur most abundantly in moist [[Tropical rainforest|tropical forests]], but mosses and lichens occur as epiphytes in almost all biomes. In Europe there are no dedicated epiphytic plants using roots, but rich assemblages of mosses and lichens grow on trees in damp areas (mainly the western coastal fringe), and the common [[Polypodium|polypody fern]] grows epiphytically along branches. Rarely, grass, small bushes or small trees may grow in [[Canopy soils|suspended soils]] up trees (typically in a rot-hole).
{{Gallery
|title=Terrestrial epiphytes
|width=180
|align=center
|File:Epiphytes (Dominica).jpg
|{{center|Epiphytes can grow on the trunks of trees or sometimes in the canopy of a tree}}
|File:Epiphytic orchid.jpg
|{{center|An epiphytic orchid on a tree in a Brazilian cloud forest}}
|File:Clinging root of epiphyte.jpg
|{{center|Clinging root of an [[orchid]]}}
}}
=== Holo-epiphyte or hemi-epiphyte ===
Epiphytes however, can generally be categorized into holo-epiphytes or hemi-epiphytes. A holo-epiphyte is a plant that spends its whole life cycle without contact with the ground and a hemi-epiphyte is a plant that spends only half of its life without the ground before the roots can reach or make contact with the ground.<ref>{{Cite journal|last1=Nieder|first1=Jürgen|last2=Prosper´ı|first2=Juliana|date=2001|title=Epiphytes and their contribution to canopy diversity|url=https://journals.ohiolink.edu/pg_99?106706970338822::NO::P99_ENTITY_ID,P99_ENTITY_TYPE:27304615,MAIN_FILE&cs=3qQvpBlUcKYGOcd_hN-qdwSXVcYkST9-7VRlGkwQDz68JuTJ_hoy9DUjfU-zwDhoDlbkjhZpoG7YFvPkDAHZkhw|journal=Plant Ecology|volume=153|pages=51–63|doi=10.1023/A:1017517119305|s2cid=37082364}}{{Dead link|date=January 2022 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> [[Orchidaceae|Orchids]] are a common example of holo-epiphytes and [[Strangler fig|Strangler Figs]] are an example of hemi-epiphytes.
=== Plant nutrient relations ===
Epiphytes are not connected to the soil, and consequently must get nutrients from other sources, such as fog, dew, rain and mist,<ref name="Zotz-2001">{{Cite journal|last1=Zotz|first1=Gerhard|last2=Hietz|first2=Peter|s2cid=22635086|date=November 2001|title=The physiological ecology of vascular epiphytes: current knowledge, open questions|journal=Journal of Experimental Botany|volume=52|issue=364|pages=2067–2078|doi=10.1093/jexbot/52.364.2067|pmid=11604445|doi-access=free}}</ref> or from nutrients being released from the ground rooted plants by decomposition or leaching, and dinitrogen fixation.<ref name="Zotz-2001" /> Epiphytic plants attached to their hosts high in the [[Canopy (forest)|canopy]] have an advantage over herbs restricted to the ground where there is less light and herbivores may be more active. Epiphytic plants are also important to certain animals that may live in their water reservoirs, such as some types of [[frog]]s and [[arthropod]]s.
Epiphytes can have a significant effect on the microenvironment of their host, and of ecosystems where they are abundant, as they hold water in the canopy and decrease water input to the soil.<ref>{{cite journal | last1 = Stanton | first1 = D.E. | last2 = Chávez | first2 = J.H. | last3 = Villegas | first3 = L. | last4 = Villasante | first4 = F. | last5 = Armesto | first5 = J. | last6 = Hedin | first6 = L.O. | last7 = Horn | first7 = H. | year = 2014| title = Epiphytes Improve Host Plant Water Use by Microenvironment Modification | journal = [[Functional Ecology (journal)|Functional Ecology]] | volume =  28| issue = 5| pages =  1274–1283| doi = 10.1111/1365-2435.12249 | doi-access = free }}</ref> Some non-vascular epiphytes such as lichens and mosses are well known for their ability to take up water rapidly.<ref>{{Cite journal|last=Johansson|first=Dick|date=1974|title=ECOLOGY OF VASCULAR EPIPHYTES IN WEST AFRICAN RAIN FOREST|url=http://www.diva-portal.org/smash/get/diva2:565496/FULLTEXT01.pdf|journal=Acta Phytogeographica Suecica|volume=59}}</ref> Epiphytes create a significantly cooler and more moist environment in the host plant canopy, potentially greatly reducing water loss by the host through transpiration.
=== Plant metabolism ===
[[Crassulacean acid metabolism|CAM metabolism]], a water-preserving metabolism present among various [[Plant taxonomy|plant taxa]], is particularly relevant to epiphytic communities.<ref>{{Cite journal |last1=Zotz |first1=Gerhard |last2=Andrade |first2=José Luis |last3=Einzmann |first3=Helena J R |date=2023-01-07 |title=CAM plants: their importance in epiphyte communities and prospects with global change |journal=Annals of Botany |volume=132 |issue=4 |pages=685–698 |doi=10.1093/aob/mcac158 |issn=0305-7364|doi-access=free |pmc=10799991 }}</ref> For example, it is estimated that among epiphytic orchids, as many as 50% are likely to use it.<ref>{{Cite journal |date=1996 |editor-last=Winter |editor-first=Klaus |editor2-last=Smith |editor2-first=J. Andrew C. |title=Crassulacean Acid Metabolism |url=https://doi.org/10.1007/978-3-642-79060-7 |journal=Ecological Studies |volume=114 |language=en |doi=10.1007/978-3-642-79060-7 |isbn=978-3-642-79062-1 |issn=0070-8356}}</ref> Other relevant epiphytic families which display such metabolism are [[Bromeliaceae|Bromeliacee]] (e.g. in genera ''[[Aechmea]]'' and ''Tillandsia''), [[Cactus|Cactaceae]] (e.g. in ''[[Rhipsalis]]'' and ''[[Epiphyllum]]'') and [[Apocynaceae]] (e.g. in ''[[Hoya (plant)|Hoya]]'' and  ''[[Dischidia]]'').
==Marine epiphytes==
The ecology of epiphytes in marine environments differs from those in terrestrial ecosystems. Epiphytes in marine systems are species of algae, bacteria, fungi, sponges, bryozoans, ascidians, protozoa, crustaceans, molluscs and any other sessile organism that grows on the surface of a plant, typically [[seagrass]]es or algae.<ref name="MV Commission">{{Cite web|url=http://www.mvcommission.org/sites/default/files/docs/Epiphytes_Wrack_feb2009.pdf|title=MV Commission}}</ref><ref name="www.seagrassli.org">{{Cite web|url=http://www.seagrassli.org/ecology/fauna_flora/epiphytes.html|title=www.SeagrassLI.org Cornell Cooperative Extension Eelgrass Restoration|website=www.seagrassli.org|access-date=2017-06-26}}</ref> Settlement of epiphytic species is influenced by a number of factors including light, temperature, currents, nutrients, and trophic interactions. Algae are the most common group of epiphytes in marine systems.<ref name="www.seagrassli.org" /> Photosynthetic epiphytes account for a large amount of the photosynthesis in systems in which they occur.<ref name="www.nps.gov">{{Cite web|url=https://www.nps.gov/bisc/learn/nature/marineplants.htm|title=Marine Plants / Algae - Biscayne National Park (U.S. National Park Service)|website=www.nps.gov|language=en|access-date=2017-06-26}}</ref> This is typically between 20 and 60% of the total primary production of the ecosystem.<ref name="www.seagrassli.org" /> They are a general group of organisms and are highly diverse, providing food for a great number of fauna.<ref name="www.nps.gov" /> Snail and nudibranch species are two common grazers of epiphytes.<ref name="www.seagrassli.org" /> Epiphyte [[species composition]] and the amount of epiphytes can be indicative of changes in the environment. Recent increases in epiphyte abundance have been linked to excessive nitrogen put into the environment from farm runoff and storm water. High abundance of epiphytes are considered detrimental to the plants that they grow on often causing damage or death, particularly in seagrasses.<ref name="MV Commission" /> This is because too many epiphytes can block access to sunlight or nutrients. Epiphytes in marine systems are known to grow quickly with very fast generation times.<ref>{{Cite web|url=http://oceanservice.noaa.gov/outreach/pdfs/coastalhypoxia.pdf|title=An Assessment of Coastal Hypoxia and Eutrophication in U.S. Waters|website=NOAA|access-date=2017-06-26|archive-date=2017-05-07|archive-url=https://web.archive.org/web/20170507184609/http://oceanservice.noaa.gov/outreach/pdfs/coastalhypoxia.pdf|url-status=dead}}</ref>
{{Gallery
|title=Marine epiphytes
|width=180
|align=center
|File:Heavy epiphyte growth on kelp stipe at Umhlali wreck PA171965.JPG
|{{center|Heavy epiphyte growth on kelp [[Stipe (botany)|stipe]]}}
|File:Notheia on Horm.jpg
|{{center|''[[Notheia anomala]]'' growing on ''[[Hormosira banksii]]''}}
|File:Cyanobacteria in symbiosis with a diatom.png
|{{center|[[Epiphytic]] ''[[Calothrix]] ''cyanobacteria (arrows) in symbiosis with a ''[[Chaetoceros]]'' diatom (scale bar 50 μm)}}
|File:Pyrophyllon-cross-section.jpg
|{{center|Cross-section of a ''[[Durvillaea antarctica]]'' frond, showing ''[[Pyrophyllon subtumens]]'' growing on the outer surface}}
}}
{{clear}}
==See also==
* ''[[Tillandsia]]'' – a genus of the [[Bromeliaceae]]
* ''[[Epiphyllum]]'' – a genus of epiphytic [[Cactus|cacti]]
* [[Parasitic plant]]
* [[Epilith]], an organism that grows in a rock
* [[Foliicolous]], lichens or bryophytes that grow on leaves of vascular plants
* [[Epiphytic bacteria]]
* [[Epiphytic fungus]]
* [[Canopy soils]]
==References==
{{Reflist}}
==External links==
* [https://www.youtube.com/watch?v=jIPy9fPiSvo Epiphytes on a Scot's Pine in Gorbie Glen, Scotland]
{{Commons category|Epiphytes}}
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[[Category:Epiphytes| ]]
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