Phytochorion

A phytochorion, in phytogeography, is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both regions overlap. The region of overlap is called a vegetation tension zone.

In traditional schemes, areas in phytogeography are classified hierarchically, according to the presence of endemic families, genera or species, e.g., in floral (or floristic, phytogeographic) zones and regions,[1] or also in kingdoms, regions and provinces,[2] sometimes including the categories empire and domain. However, some authors prefer not to rank areas, referring to them simply as "areas", "regions" (in a non hierarchical sense) or "phytochoria".[3]

Systems used to classify vegetation can be divided in two major groups: those that use physiognomic-environmental parameters and characteristics and those that are based on floristic (i.e. shared genera and species) relationships.[4] Phytochoria are defined by their plant taxonomic composition, while other schemes of regionalization (e.g., vegetation type, physiognomy, plant formations, biomes) may variably take in account, depending on the author, the apparent characteristics of a community (the dominant life-form), environment characteristics, the fauna associated, anthropic factors or political-conservationist issues.[5]

Explanation

Several systems of classifying geographic areas where plants grow have been devised. Most systems are organized hierarchically, with the largest units subdivided into smaller geographic areas, which are made up of smaller floristic communities, and so on. Phytochoria are defined as areas possessing a large number of endemic taxa. Floristic kingdoms are characterized by a high degree of family endemism, floristic regions by a high degree of generic endemism, and floristic provinces by a high degree of species endemism. Systems of phytochoria have both significant similarities and differences with zoogeographic provinces, which follow the composition of mammal families, and with biogeographical provinces or terrestrial ecoregions, which take into account both plant and animal species.

The term "phytochorion" (Werger & van Gils, 1976)[6] is especially associated with the classifications according to the methodology of Josias Braun-Blanquet, which is tied to the presence or absence of particular species,[7] mainly in Africa.[8]

Taxonomic databases tend to be organized in ways which approximate floristic provinces, but which are more closely aligned to political boundaries, for example according to the World Geographical Scheme for Recording Plant Distributions.

Early schemes

In the late 19th century, Adolf Engler (1844-1930) was the first to make a world map with the limits of distribution of floras, with four major floral regions (realms).[9][10] His Syllabus der Pflanzenfamilien, from the third edition (1903) onwards, also included a sketch of the division of the earth into floral regions.[11]

Other important early works on floristics includes Augustin de Candolle (1820),[12] Schouw (1823),[13]Alphonse de Candolle (1855),[14] Drude (1890),[1] Diels (1908),[15] and Rikli (1913).[16]

Good (1947) regionalization

Florenreiche
Good (1947) floristic kingdoms

Botanist Ronald Good (1947) identified six floristic kingdoms (Boreal or Holarctic, Neotropical, Paleotropical, South African, Australian, and Antarctic), the largest natural units he determined for flowering plants. Good's six kingdoms are subdivided into smaller units, called regions and provinces. The Paleotropical kingdom is divided into three subkingdoms, which are each subdivided into floristic regions. Each of the other five kingdoms are subdivided directly into regions. There are a total of 37 floristic regions. Almost all regions are further subdivided into floristic provinces.[17]

Takhtajan (1978, 1986) regionalization

Armen Takhtajan (1978, 1986), in a widely used scheme that builds on Good's work, identified thirty-five floristic regions, each of which is subdivided into floristic provinces, of which there are 152 in all.[18][19][20][21]

Holarctic Kingdom

Floristic regions in Europe (english)
Flora regions in Europe

I. Circumboreal region

1 Arctic province
2 Atlantic Europe province
3 Central Europe province
4 Illyria or Balkan province
5 Pontus Euxinus province
6 Caucasus province
7 Eastern Europe province
8 Northern Europe province
9 Western Siberia province
10 Altai-Sayan province
11 Central Siberia province
12 Transbaikalia province
13 Northeastern Siberia province
14 Okhotsk-Kamchatka province
15 Canada incl. Great Lakes province

II. Eastern Asiatic region

16 Manchuria province
17 Sakhalin-Hokkaidō province
18 Japan-Korea province
19 Volcano-Bonin province
20 Ryūkyū or Tokara-Okinawa province
21 Taiwan province
22 Northern China province
23 Central China province
24 Southeastern China province
25 Sikang-Yuennan province
26 Northern Burma province
27 Eastern Himalaya province
28 Khasi-Manipur province

III. North American Atlantic Region

29 Appalachian Province (forested areas extending east to include the piedmont and west to the start of the prairies)
30 Atlantic and Gulf Coastal Plain Province
31 North American Prairies Province

IV. Rocky Mountain Floristic Region

32 Vancouverian province
33 Rocky Mountains province

V. Macaronesian region

34 Azores province
35 Madeira province
36 Canaries province
37 Cape Verde province

VI. Mediterranean region

38 Southern Morocco province
39 Southwestern Mediterranean province
40 South Mediterranean province
41 Iberia province
42 Baleares province
43 Liguria-Tyrrhenia province
44 Adriatic province
45 East Mediterranean province
46 Crimea-Novorossijsk province

VII. Saharo-Arabian region

47 Sahara province
48 Egypt-Arabia province

VIII. Irano-Turanian region

49 Mesopotamia province
50 Central Anatolia province
51 Armenia-Iran province
52 Hyrcania province
53 Turania or Aralo-Caspia province
54 Turkestan province
55 Northern Baluchistan province
56 Western Himalaya province
57 Central Tien Shan province
58 Dzungaria-Tien Shan province
59 Mongolia province
60 Tibet province

IX. Madrean Region

61 Great Basin province
62 Californian province
63 Sonoran province
64 Mexican Highlands province

Paleotropical Kingdom

The Conservation Atlas of Tropical Forests- Africa (1992) (20689316341)
Main phytochoria of Africa and Madagascar

X. Guineo-Congolian region

65 Upper Guinean forests province
66 Nigeria-Cameroon province
67 Congo province

XI. Usambara-Zululand region

68 Zanzibar-Inhambane province
69 Tongoland-Pondoland province

XII. Sudano-Zambezian region

70 Zambezi province
71 Sahel province
72 Sudan province
73 Somalia-Ethiopia province
74 South Arabia province
75 Socotra province
76 Oman province
77 South Iran province
78 Sindia province

XIII. Karoo-Namib region

79 Namibia province
80 Namaland province
81 Western Cape province
82 Karoo province

XIV. St. Helena and Ascension region

83 St. Helena and Ascension province

XV. Madagascan region

84 Eastern Madagascar province
85 Western Madagascar province
86 Southern and Southwestern Madagascar province
87 Comoro province
88 Mascarenes province
89 Seychelles province

XVI. Indian region

90 Ceylon (Sri Lanka) province
91 Malabar province
92 Deccan province
93 Upper Gangetic Plain province
94 Bengal province

XVII. Indochinese region

95 South Burma province
96 Andamans province
97 South China province
98 Thailand province
99 North Indochina province
100 Annam province
101 South Indochina province

XVIII. Malesian region

102 Malaya province
103 Borneo province
104 Philippines province
105 Sumatra province
106 South Malesia province
107 Celebes province
108 Moluccas and West New Guinea province
109 Papua province
110 Bismarck Archipelago province

XIX. Fijian region

111 New Hebrides province
112 Fiji province

XX. Polynesian region

113 Micronesia province
114 Polynesia province

XXI. Hawaiian region

115 Hawaii province

XXII. Neocaledonian region

116 New Caledonia province

Neotropical Kingdom

XXIII. Caribbean region

117 Central America province
118 West Indies province
119 Galápagos Islands province

XXIV. region of the Guayana Highlands

120 The Guianas province

XXV. Amazon region

121 Amazonia province
122 Llanos province

XXVI. Brazilian region

123 Caatinga province
124 Central Brazilian Uplands province
125 Chaco province
126 Atlantic province
127 Paraná province

XXVII. Andean region

128 Northern Andes province
129 Central Andes province

South African Kingdom

XXVIII. Cape region

130 Cape province

Australian Kingdom

XXIX. Northeast Australian region

131 North Australia province
132 Queensland province
133 Southeast Australia province
134 Tasmania province

XXX. Southwest Australian region

135 Southwest Australia province

XXXI. Central Australian or Eremaean region

136 Eremaea province

Antarctic Kingdom

XXXII. Fernandezian region

137 Juan Fernández province

XXXIII. Chile-Patagonian region

138 Northern Chile province
139 Central Chile province
140 Pampas province
141 Patagonia province
142 Tierra del Fuego province

XXXIV. region of the South Subantarctic Islands

143 Tristan-Gough province
144 Kerguelen province

XXXV. Neozeylandic region

145 Lord Howe province
146 Norfolk province
147 Kermadec province
148 Northern New Zealand province
149 Central New Zealand province
150 Southern New Zealand province
151 Chatham province
152 New Zealand Subantarctic Islands province

References

  1. ^ a b Drude, O. (1890). Handbuch der Pflanzengeographie. Stuttgart: Engelhorn, [1], [2]. French translation: Manuel de géographie botanique. Paris: P. Klincksieck, 1897. 552 p., [3].
  2. ^ Braun-Blanquet, J. (1932). Plant sociology; the study of plant communities. New York and London, McGraw-Hill, [4].
  3. ^ Linder, Lovett, Mutke, et al. (2005): A numerical re-evaluation of the sub-Saharan phytochoria. Biologiske Skrifter 55: 229-252.
  4. ^ JOLY, C.A., AIDAR, M.P.M., KLINK, C.A., McGRATH, D.G., MOREIRA, A.G., MOUTINHO, P., NEPSTAD, D.C., OLIVEIRA, A.A.; POTT, A.; RODAL, M.J.N. & SAMPAIO, E.V.S.B. 1999. Evolution of the Brazilian phytogeography classification systems: implications for biodiversity conservation. Ci. e Cult. 51: 331-348.
  5. ^ Magno Coutinho, L. (2006) O conceito de bioma. Acta bot. bras. 20(1): 13-23.
  6. ^ Werger, M. J. A. & H. van Gils. 1976. Phytosociological classification problems in chorological border line areas. J. Biogeogr. 3: 49–54, [5].
  7. ^ glossary from Bredenkamp, George J.; Granger, J. Ed; Hoffman, M. Timm; Lubke, Roy A.; Mckenzie, Bruce; Rebelo, A. (Tony) & Noel, van Rooyen (February 1998). Low, A. Barrie & Rebelo, A. (Tony) G. (eds.). Vegetation of South Africa, Lesotho and Swaziland: A companion to the Vegetation Map of South Africa, Lesotho and Swaziland. Department of Environmental Affairs and Tourism, Pretoria.
  8. ^ Prance, G. T. (1989). American Tropical forests, in Ecosystems of the World, Vol. 14B. Tropical Rain Forest Ecosystems, (eds H. Lieth and M. J. A. Werger), Elsevier, Amsterdam, pp. 99–132, [6].
  9. ^ Engler, A. (1879-1882). Versuch einer Entwicklungsgeschichte der Pflanzenwelt. 2 vols., Leipzig.
  10. ^ Cox, C. B., Moore, P.D. & Ladle, R. J. 2016. Biogeography: an ecological and evolutionary approach. 9th edition. John Wiley & Sons: Hoboken, p. 10, [7].
  11. ^ Engler, Adolf (1903). Syllabus der Pflanzenfamilien: eine Übersicht über das gesamte Pflanzensystem mit Berücksichtigung der Medicinal- und Nutzpflanzen nebst einer Übersicht über die Florenreiche und Florengebiete der Erde zum Gebrauch bei Vorlesungen und Studien über specielle und medicinisch-pharmaceutische Botanik (3rd ed.). Berlin: Gebrüder Borntraeger Verlag. p. 233. Retrieved 31 January 2014.
  12. ^ de Candolle, Augustin (1820). Essai Élémentaire de Géographie Botanique. In: Dictionnaire des sciences naturelles, Vol. 18. Flevrault, Strasbourg, [8].
  13. ^ Schouw, J. F. (1822). Grundtræk til en almindelig Plantegeographie. Copenhagen, Gyldendalske Boghandels Forlag. German translation: Grundzüge einer allgemeinen Pflanzengeographie, Berlin, 1823, [9].
  14. ^ de Candolle, Alphonse (1855). Géographie botanique raisonnée. Paris: V. Masson, [10].
  15. ^ Diels, L. (1908). Pflanzengeographie. Göschen, Leipzig, [11]; 5th ed. rev. 1958 (F. Mattick), De Gruyter, Berlin.
  16. ^ Rikli, M. (1913). "Geographie der Pflanzen (Die Florenreiche)". In: Handwörterbuch der Naturwissenschaften 4:776–857, [12].
  17. ^ Good, R. (1947). The Geography of Flowering Plants. Longmans, Green and Co, New York, [13]. 2nd ed., 1953, [14].
  18. ^ Takhtajan, A. 1969. Flowering plants: origin and dispersal. Transl. by C. Jeffrey. Oliver &. Boyd, Edinburgh. 310 pp. [15].
  19. ^ Тахтаджян А. Л. Флористические области Земли / Академия наук СССР. Ботанический институт им. В. Л. Комарова. — Л.: Наука, Ленинградское отделение, 1978. — 247 с. — 4000 экз. DjVu, Google Books.
  20. ^ Takhtajan, A. (1986). Floristic Regions of the World. (translated by T.J. Crovello & A. Cronquist). University of California Press, Berkeley, PDF, DjVu.
  21. ^ Cox, C. B. (2001). The biogeographic regions reconsidered. Journal of Biogeography, 28: 511-523, [16].

Bibliography

  • Frodin, D.G. (2001). Guide to Standard Floras of the World. An annotated, geographically arranged systematic bibliography of the principal floras, enumerations, checklists and chorological atlases of different areas. 2nd ed. (1st edn 1984), pp. xxiv, 1100, .Cambridge University Press, Cambridge, [17].
António Rodrigo Pinto da Silva

António Rodrigo Pinto da Silva (Porto, March 13, 1912 – Lisbon, September 28, 1992), often referred to as A.R. Pinto da Silva or P. Silva, was a Portuguese botanist who distinguished himself as a taxonomist and phytosociologist when he collaborated with Swiss botanist Josias Braun-Blanquet and also with Pierre Dansereau.

His studies on taxonomy and floristic yielded a substantial number of new taxa and a better knowledge about many plants and its nomenclature. He organized the Estação Agronómica Nacional's (National Agronomic Station) herbarium, which he rose from 3000 to almost 100,000 entries. He was a pioneer on ethnobotany studies in Portugal and published several contributions on vernacular nomenclature of Portuguese flora, cultivated plants and popular use of wild plants as food. For half a century he helped archaeologists, having published numerous works on paleoethnobotany, among more than 300 articles, notes and communications published throughout his life both in Portuguese and foreign publications.

Biodiversity of Cape Town

Biodiversity of Cape Town is the variety and variability of life within the geographical extent of Cape Town. The terrestrial vegetation is particularly diverse and much of it is endemic to the city and its vicinity. Terrestrial and freshwater animal life is heavily impacted by urban development and habitat degradation. Marine life of the waters immediately adjacent to the city is also diverse, and while also impacted by human activity, the habitats are relatively intact.

Biogeography

Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, isolation and habitat area. Phytogeography is the branch of biogeography that studies the distribution of plants. Zoogeography is the branch that studies distribution of animals.

Knowledge of spatial variation in the numbers and types of organisms is as vital to us today as it was to our early human ancestors, as we adapt to heterogeneous but geographically predictable environments. Biogeography is an integrative field of inquiry that unites concepts and information from ecology, evolutionary biology, geology, and physical geography.Modern biogeographic research combines information and ideas from many fields, from the physiological and ecological constraints on organismal dispersal to geological and climatological phenomena operating at global spatial scales and evolutionary time frames.

The short-term interactions within a habitat and species of organisms describe the ecological application of biogeography. Historical biogeography describes the long-term, evolutionary periods of time for broader classifications of organisms. Early scientists, beginning with Carl Linnaeus, contributed to the development of biogeography as a science. Beginning in the mid-18th century, Europeans explored the world and discovered the biodiversity of life.

The scientific theory of biogeography grows out of the work of Alexander von Humboldt (1769–1859), Hewett Cottrell Watson (1804–1881), Alphonse de Candolle (1806–1893), Alfred Russel Wallace (1823–1913), Philip Lutley Sclater (1829–1913) and other biologists and explorers.

Ecoregions of Madagascar

The ecoregions of Madagascar, as defined by the World Wildlife Fund, include seven terrestrial, five freshwater, and two marine ecoregions. Madagascar's diverse natural habitats harbour a rich fauna and flora with high levels of endemism, but most ecoregions suffer from habitat loss.

Flora of St Helena

The flora of Saint Helena, an isolated island in the South Atlantic Ocean, is exceptional in its high level of endemism and the severe threats facing the survival of the flora. In phytogeography, it is in the phytochorion St. Helena and Ascension Region of the African Subkingdom, in the Paleotropical Kingdom.

Great Basin Floristic Province

The Great Basin Floristic Province is a floristic province of the Madrean Subkingdom (floristic region), in the Boreal Kingdom (floristic kingdom). It is located in the Western United States.

A floristic province (otherwise known as a phytochorion) is a concept defined by Ronald Good, in 1947, and refined by Armen Takhtajan, in 1986. A phytochorion is a region on earth that has a relative constant composition of plants. Takhtajan defined the Great Basin Floristic Province to extend well beyond the boundaries of the hydrographically defined Great Basin: it includes the Snake River Plain, the Colorado Plateau, the Uinta Basin, and parts of Arizona north of the Mogollon Rim. The Great Basin phytochorion is distinguished by the presence of Great Basin sagebrush (Artemisia tridentata), and saltbushes in genus Atriplex.The Great Basin floristic province is one geographical division scheme for the Intermountain West, amongst many. Other classifications are proposed by the U.S. Environmental Protection Agency (i.e., the Central Basin and Range ecoregion and the Northern Basin and Range ecoregion), and by the World Wildlife Fund (i.e., Great Basin shrub steppe and Great Basin montane forests)

The larger deserts of the Great Basin Province are: the Great Basin Desert (39,505 square miles (102,320 km2) in Nevada; and the Great Salt Lake Desert (4,000 square miles (10,000 km2) and Escalante Desert (3,270 square miles (8,500 km2) in Utah.

Les Baux-de-Provence

Les Baux-de-Provence (French pronunciation: ​[le bo də pʁɔvɑ̃s]; Occitan: Lei Bauç de Provença) is a French commune in the Bouches-du-Rhône department of the province of Provence in the Provence-Alpes-Côte d'Azur region of southern France. It has a spectacular position in the Alpilles mountains, set atop a rocky outcrop that is crowned with a ruined castle overlooking the plains to the south. Its name refers to its site: in Provençal, a bauç is a rocky spur. The name bauxite (Aluminium ore) is derived from the village name when it was first discovered there by geologist Pierre Berthier in 1821.

It has been named one of the most beautiful villages in France and has over 1.5 million visitors per year although it has only 22 residents in the upper part of the commune and 436 for the whole commune. Inhabitants of the commune are known as Baussencs or Baussenques.

List of codes used in the World Geographical Scheme for Recording Plant Distributions

The World Geographical Scheme for Recording Plant Distributions (WGSRPD) is a biogeographical system developed by the international Biodiversity Information Standards (TDWG) organization, formerly the International Working Group on Taxonomic Databases. The system provides clear definitions and codes for recording plant distributions at four scales or levels, from "botanical continents" down to parts of large countries. Current users of the system include the International Union for Conservation of Nature (IUCN), the Germplasm Resources Information Network (GRIN), and the World Checklist of Selected Plant Families (WCSP). Plants of the World Online uses Kew's data sources, and hence also uses the WGSRPD for distributions.

Malesia

Malesia is a biogeographical region straddling the Equator and the boundaries of the Indomalaya ecozone and Australasia ecozone, and also a phytogeographical floristic region in the Paleotropical Kingdom. It has been given different definitions. The World Geographical Scheme for Recording Plant Distributions split off Papuasia in its 2001 version.

Upper Guinea

Upper Guinea is a geographical term used in several contexts:

Upper Guinea (French: Haute-Guinée) is one of the four geographic regions of the Republic of Guinea, being east of Futa Jalon, north of Forest Guinea, and bordering Mali. The population of this region is mainly Malinke.

In a larger sense, it refers to a large plain covering eastern Guinea, Sierra Leone, Liberia and extending into north western Côte d'Ivoire. Mostly forming the upper watershed of the River Niger, it is sparsely populated and is home to the Haut Niger National Park.

Upper Guinea can also refer to the interior part of the wider Guinea region, bordering the Sahel. The interior regions are largely defined by the watersheds of rivers that arise from Fouta Djallon, including the Niger, Senegal, Faleme and others. The term was widely applied during the sixteenth to nineteenth centuries to describe a coastal region and its related hinterland with which Europeans traded.

In biogeography, Upper Guinea refers the region of tropical rainforest extending from southwestern Guinea through Sierra Leone, Liberia, southeastern Guinea, Côte d'Ivoire, and southwestern Ghana. The Dahomey Gap, a drier region of Ghana, Togo, and Benin where the Guinean forest-savanna mosaic extends to the Gulf of Guinea, separates Upper Guinea from the tropical rainforests of Lower Guinea further east. The Upper Guinea forests are also recognized as an endemic bird area.

Upper Guinean forests

The Upper Guinean forests is a tropical seasonal forest region of West Africa. The Upper Guinean forests extend from Guinea and Sierra Leone in the west through Liberia, Côte d'Ivoire and Ghana to Togo in the east, and a few hundred kilometers inland from the Atlantic coast. A few enclaves of montane forest lie further inland in the mountains of central Guinea and central Togo and Benin.In the drier interior, the Upper Guinean forests yield to the Guinean forest-savanna mosaic, a belt of dry forests and savannas that lies between the coastal forests and the savannas and grasslands of the Sudan further north. The Dahomey Gap, a region of Togo and Benin where the Guinean forest-savanna mosaic extends to the Atlantic coast, separates the Upper Guinean forests from the Lower Guinean forests to the east, which extend from eastern Benin through Nigeria, Cameroon, and south along the coast of the Gulf of Guinea. The Upper Guinean forests are a Global 200 ecoregion.The Guinean moist forests are much affected by winds from the hot dry area to the north and the cool Atlantic currents. This gives the region a very seasonal climate with over 80 in (203 cm) of rain falling in some areas in the wet season. Over 2000 species of vascular plant have been recorded in the ecoregion, and mammals found here include the chimpanzee (Pan troglodytes), leopard (Panthera pardus), pygmy hippopotamus (Hexaprotodon liberiensis), Ogilby's duiker (Cephalophus ogilbyi), Nimba otter shrew (Micropotamogale lamottei) and the African golden cat (Profelis aurata). There are twenty-one endemic and near-endemic forest birds in the ecoregion of which three, Nimba Flycatcher Melaenornis annamarulae, Gola Malimbe Malimbus ballmanni and Spot-winged Greenbul Phyllastrephus leucolepis are further restricted in distribution to the western forests only.The World Wide Fund for Nature (WWF) designated the Upper Guinean forests, which it calls the Guinean moist forests, as one of its Global 200 critical regions for conservation.

The WWF divides the Upper Guinean forests into three ecoregions:

The Western Guinean lowland forests extend from Guinea and Sierra Leone through Liberia and southeastern Côte d'Ivoire as far as the Sassandra River.

The Eastern Guinean forests extend east from the Sassandra River through Côte d'Ivoire and Ghana to western Togo, with a few isolated enclaves further inland in the highlands of central Togo and Benin.

The Guinean montane forests are found at higher elevations in the Guinea Highlands, which extend through central and southeastern Guinea, northern Sierra Leone, and eastern Côte d'Ivoire.

World Geographical Scheme for Recording Plant Distributions

The World Geographical Scheme for Recording Plant Distributions (WGSRPD) is a biogeographical system developed by the international Biodiversity Information Standards (TDWG) organization, formerly the International Working Group on Taxonomic Databases. The WGSRPD standards, like other standards for data fields in botanical databases, were developed to promote "the wider and more effective dissemination of information about the world's heritage of biological organisms for the benefit of the world at large". The system provides clear definitions and codes for recording plant distributions at four scales or levels, from "botanical continents" down to parts of large countries. Current users of the system include the International Union for Conservation of Nature (IUCN), the Germplasm Resources Information Network (GRIN), and the World Checklist of Selected Plant Families (WCSP).

Floristic regions of the world
Holarctic Kingdom
Paleotropical Kingdom
Neotropical Kingdom
South African Kingdom
Australian Kingdom
Antarctic Kingdom

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