Phytogeography

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Phytogeography (from Greek φυτόν, phytón = "plant" and γεωγραφία, geographía = "geography" meaning also distribution) or botanical geography is the branch of biogeography that is concerned with the geographic distribution of plant species and their influence on the earth's surface. [1] Phytogeography is concerned with all aspects of plant distribution, from the controls on the distribution of individual species ranges (at both large and small scales, see species distribution) to the factors that govern the composition of entire communities and floras. Geobotany, by contrast, focuses on the geographic space's influence on plants.[ citation needed ]

Contents

Fields

Phytogeography is part of a more general science known as biogeography. [2] Phytogeographers are concerned with patterns and process in plant distribution. Most of the major questions and kinds of approaches taken to answer such questions are held in common between phyto- and zoogeographers.

Phytogeography in wider sense (or geobotany, in German literature) encompasses four fields, according with the focused aspect, environment, flora (taxa), vegetation (plant community) and origin, respectively: [3] [4] [5] [6]

Phytogeography is often divided into two main branches: ecological phytogeography and historical phytogeography. The former investigates the role of current day biotic and abiotic interactions in influencing plant distributions; the latter are concerned with historical reconstruction of the origin, dispersal, and extinction of taxa.[ citation needed ]

Overview

The basic data element of phytogeography are specimen records. These are collected individual plants like this one, a Cinnamon Fern, collected in the Great Smoky Mountains of North Carolina. Cinnamon fern smokies.jpg
The basic data element of phytogeography are specimen records. These are collected individual plants like this one, a Cinnamon Fern, collected in the Great Smoky Mountains of North Carolina.

The basic data elements of phytogeography are occurrence records (presence or absence of a species) with operational geographic units such as political units or geographical coordinates. These data are often used to construct phytogeographic provinces (floristic provinces) and elements.

The questions and approaches in phytogeography are largely shared with zoogeography, except zoogeography is concerned with animal distribution rather than plant distribution. The term phytogeography itself suggests a broad meaning. How the term is actually applied by practicing scientists is apparent in the way periodicals use the term. The American Journal of Botany , a monthly primary research journal, frequently publishes a section titled "Systematics, Phytogeography, and Evolution." Topics covered in the American Journal of Botany's "Systematics and Phytogeography" section include phylogeography, distribution of genetic variation and, historical biogeography, and general plant species distribution patterns. Biodiversity patterns are not heavily covered. A flora is the group of all plant species in a specific period of time or area, in which each species is independent in abundance and relationships to the other species. The group or the flora can be assembled in accordance with floral element, which are based on common features. A flora element can be a genetic element, in which the group of species share similar genetic information i.e. common evolutionary origin; a migration element has a common route of access into a habitat; a historical element is similar to each other in certain past events and an ecological element is grouped based on similar environmental factors. A population is the collection of all interacting individuals of a given species, in an area.

An area is the entire location where a species, an element or an entire flora can occur. Aerography studies the description of that area, chorology studies their development. The local distribution within the area as a whole, as that of a swamp shrub, is the topography of that area. Areas are an important factor is forming an image about how species interaction result in their geography. The nature of an area’s margin, their continuity, their general shape and size relative to other areas, make the study of area crucial in identifying these types of information. For example, a relict area is an area surviving from an earlier and more exclusive occurrence. Mutually exclusive plants are called vicarious (areas containing such plants are also called vicarious). The earth’s surface is divided into floristic region, each region associated with a distinctive flora. [7]

History

An 1814 self-portrait in Paris of Alexander von Humboldt. Humboldt is often referred to as the "father of phytogeography". Alexander von Humboldt-selfportrait.jpg
An 1814 self-portrait in Paris of Alexander von Humboldt. Humboldt is often referred to as the "father of phytogeography".

Phytogeography has a long history. One of the subjects earliest proponents was Prussian naturalist Alexander von Humboldt, who is often referred to as the "father of phytogeography". Von Humboldt advocated a quantitative approach to phytogeography that has characterized modern plant geography.

Gross patterns of the distribution of plants became apparent early on in the study of plant geography. For example, Alfred Russel Wallace, co-discoverer of the principle of natural selection, discussed the Latitudinal gradients in species diversity, a pattern observed in other organisms as well. Much research effort in plant geography has since then been devoted to understanding this pattern and describing it in more detail.

In 1890, the United States Congress passed an act that appropriated funds to send expeditions to discover the geographic distributions of plants (and animals) in the United States. The first of these was The Death Valley Expedition, including Frederick Vernon Coville, Frederick Funston, Clinton Hart Merriam, and others. [8]

Research in plant geography has also been directed to understanding the patterns of adaptation of species to the environment. This is done chiefly by describing geographical patterns of trait/environment relationships. These patterns termed ecogeographical rules when applied to plants represent another area of phytogeography.

Floristic regions

Good (1947) floristic kingdoms Florenreiche.jpg
Good (1947) floristic kingdoms

Floristics is a study of the flora of some territory or area. Traditional phytogeography concerns itself largely with floristics and floristic classification,.

China has been a focus to botanist for its rich biota as it holds the record for the earliest known angiosperm megafossil. [9]

See also

Related Research Articles

Biogeography Study of the distribution of species and ecosystems in geographic space and through geological time

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. Mycogeography is the branch that studies distribution of fungi, such as mushrooms.

Ecological classification or ecological typology is the classification of land or water into geographical units that represent variation in one or more ecological features. Traditional approaches focus on geology, topography, biogeography, soils, vegetation, climate conditions, living species, habitats, water resources, and sometimes also anthropic factors. Most approaches pursue the cartographical delineation or regionalisation of distinct areas for mapping and planning.

Vegetation Assemblage of plant species

Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader than the term flora which refers to species composition. Perhaps the closest synonym is plant community, but vegetation can, and often does, refer to a wider range of spatial scales than that term does, including scales as large as the global. Primeval redwood forests, coastal mangrove stands, sphagnum bogs, desert soil crusts, roadside weed patches, wheat fields, cultivated gardens and lawns; all are encompassed by the term vegetation.

Malesia Biogeographical region in Southeast Asia

Malesia is a biogeographical region straddling the Equator and the boundaries of the Indomalayan and Australasian realms, 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.

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.

Antarctic flora Distinct community of plants which evolved on the supercontinent of Gondwana

The Antarctic flora is a distinct community of vascular plants which evolved millions of years ago on the supercontinent of Gondwana. It is now found on several separate areas of the Southern Hemisphere, including southern South America, southernmost Africa, New Zealand, Australia and New Caledonia. Joseph Dalton Hooker was the first to notice similarities in the flora and speculated that Antarctica had served as either a source or a transitional point, and that land masses now separated might formerly have been adjacent.

Endemism Ecological state of being unique to a defined geographic location or habitat

Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be endemic to that particular part of the world.

Zoogeography Science of the geographic distribution of animal species

Zoogeography is the branch of the science of biogeography that is concerned with geographic distribution of animal species.

Phytosociology, also known as phytocoenology or simply plant sociology, is the study of groups of species of plant that are usually found together. Phytosociology aims to empirically describe the vegetative environment of a given territory. A specific community of plants is considered a social unit, the product of definite conditions, present and past, and can exist only when such conditions are met. In phytosociology such as unit is known as a phytocoenosis. A phytocoenosis is more commonly known as a plant community, and consists of the sum of all plants in a given area. It is a subset of a biocoenosis, which consists of all organisms in a given area. More strictly speaking, a phytocoenosis is a set of plants in area that are interacting with each other through competition or other ecological processes. Coenoses are not equivalent to ecosystems, which consist of organisms and the physical environment that they interact with. A phytocoensis has a distribution which can be mapped. Phytosociology has a system for describing and classifying these phytocoenoses in a hierarchy, known as syntaxonomy, and this system has a nomenclature. The science is most advanced in Europe, Africa and Asia.

Léon Croizat Italian botanist (1894–1982)

Leon Camille Marius Croizat was a French-Italian scholar and botanist who developed an orthogenetic synthesis of evolution of biological form over space, in time, which he called panbiogeography.

Tyge W. Böcher

Tyge Wittrock Böcher was a Danish botanist, evolutionary biologist, plant ecologist and phytogeographer.

Carl Hansen Ostenfeld Danish systematic botanist

Carl Emil Hansen Ostenfeld was a Danish systematic botanist. He graduated from the University of Copenhagen under professor Eugenius Warming. He was a keeper at the Botanical Museum 1900–1918, when he became professor of botany at the Royal Veterinary and Agricultural University. In 1923, by the early retirement of Raunkiær's, Ostenfeld became professor of botany at the University of Copenhagen and director of the Copenhagen Botanical Garden, both positions held until his death in 1931. He was a member of the Royal Danish Academy of Sciences and Letters and served on the board of directors of the Carlsberg Foundation.

Alvar Palmgren

Alvar Palmgren was a Finnish botanist and plant ecologist.

Flora of Australia Plant species of Australia

The flora of Australia comprises a vast assemblage of plant species estimated to over 30,000 vascular and 14,000 non-vascular plants, 250,000 species of fungi and over 3,000 lichens. The flora has strong affinities with the flora of Gondwana, and below the family level has a highly endemic angiosperm flora whose diversity was shaped by the effects of continental drift and climate change since the Cretaceous. Prominent features of the Australian flora are adaptations to aridity and fire which include scleromorphy and serotiny. These adaptations are common in species from the large and well-known families Proteaceae (Banksia), Myrtaceae, and Fabaceae.

Otto Sendtner was a German botanist and phytogeographer born in Munich.

The Oman Botanic Garden is a development of the Diwan of Royal Court in Oman, with unique plants, landscapes, and cultural traditions of Oman. The gardens are located on 423 hectares in Al Khoud, about 20 kilometers from the capital Muscat. The garden showcases all of the native plant species of Oman in a series of man-made naturalistic habitats from the dry deserts to the rich monsoon cloud forests. The garden also showcases the traditionally cultivated crops, with information on how plants are used by the people of Oman. It presents an opportunity for visitors to experience the flora and vegetation of Oman while learning about the agricultural heritage, cultural traditions, and hospitality of the country.

Vegetation classification is the process of classifying and mapping the vegetation over an area of the earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource and environmental management. Many different methods of vegetation classification have been used. In general, there has been a shift from structural classification used by forestry for the mapping of timber resources, to floristic community mapping for biodiversity management. Whereas older forestry-based schemes considered factors such as height, species and density of the woody canopy, floristic community mapping shifts the emphasis onto ecological factors such as climate, soil type and floristic associations. Classification mapping is usually now done using geographic information systems (GIS) software.

Biomes in Brazil

According to IBGE (2004), Brazil has its territory occupied by six terrestrial biomes and one marine biome.

Andrei Krasnov Russian botanist and geographer (1862–1914)

Andrei Nikolaevich Krasnov was a Russian botanist who explored the plants of Turkestan, Altai, Nizhny Novgorod, Tian Shan and the Caucasus regions. He was a professor at the University of Kharkov. His major contribution was in phytogeography, identifying combinations of species found in different regions and contributing to the study of global vegetation patterns and their links to the Köppen climate classification.

Johan Petter Norrlin Finnish botanist

Johan Petter Norrlin was a Finnish botanist and a professor of botany at the University of Helsinki from 1879 to 1903. He was a pioneer of plant geography in Finland, and is also well known for his work on lichens and on the taxonomy of the apomictic taxa of the plant genera Hieracium and Pilosella.

References

  1. Sambamurty, A. V. S. S. (2010-10-07). Taxonomy of Angiosperms. I. K. International Pvt Ltd. p. 188. ISBN   978-81-88237-16-6.
  2. Craw, Robin C.; Grehan, John R.; Heads, Michael J. (1999-04-15). Panbiogeography: Tracking the History of Life. Oxford University Press. p. 145. ISBN   978-0-19-536069-1.
  3. Rizzini, Carlos Toledo (1997). Tratado de fitogeografia do Brasil: aspectos ecológicos, sociológicos e florísticos (in Portuguese) (2 ed.). Rio de Janeiro: Âmbito Cultural Edições. pp. 7–11.
  4. Mueller-Dombois, Dieter; Ellenberg, Heinz (August 1974). Aims and Methods of Vegetation Ecology. New York: John Wiley and Sons. ISBN   1-930665-73-3. See Mueller-Dombois (2001), p. 567, .
  5. Pott, Richard (2005). Allgemeine Geobotanik: Biogeosysteme und Biodiversität (in German). Berlin: Springer Spektrum. p. 13. ISBN   978-3540230588.
  6. Vulf, E. V. (1943). An Introduction to Historical Plant Geography. Translated by Brissenden, Elizabeth. Waltham, Massachusetts: Chronica Botanica Company.
  7. Plant Geography. (n.d.). Retrieved from https://encyclopedia2.thefreedictionary.com/Plant Geography
  8. "Death Valley Expedition (1891)". Historical Expeditions. Smithsonian National Museum of Natural History. Archived from the original on 1 April 2017.
  9. QIAN, HONG; WANG, SILONG; HE, JIN-SHENG; ZHANG, JUNLI; WANG, LISONG; WANG, XIANLI; GUO, KE (November 2006). "Phytogeographical Analysis of Seed Plant Genera in China". Annals of Botany. 98 (5): 1073–1084. doi:10.1093/aob/mcl192. ISSN   0305-7364. PMC   3292247 . PMID   16945946.

Bibliography