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Plant Communities
A plant community is a collection or Association (ecology), association of plant species within a designated geographical unit, which forms a relatively uniform patch, distinguishable from neighboring patches of different vegetation types. The components of each plant community are influenced by soil type, topography, climate and human disturbance. In many cases there are several soil types present within a given plant community. This is because the soil type within an area is influenced by two factors, the rate at which water infiltrates or exits (via evapotranspiration) the soil, as well as the rate at which organic matter (any carbon-based compound within the environment, such as decaying plant matter) enters or decays from the soil. Plant communities are studied substantially by ecologists, due to providing information on the effects of dispersal, tolerance to environmental conditions, and response to disturbance of a variety of plant species, information valuable to the comprehe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Association (ecology)
In phytosociology and community ecology an association is a type of community (ecology), ecological community with a predictable species composition and consistent physiognomy (structural appearance) which occurs in a particular habitat type. The term was first coined by Alexander von Humboldt and formalised by the International Botanical Congress in 1910. An association can be viewed as a real, integrated entity shaped either by species interactions or by similar habitat requirements, or it can be viewed as merely a common point along a continuum. The former view was championed by American ecologist Frederic Clements, who viewed the association as a whole that was more than the sum of its parts, and by Josias Braun-Blanquet, a Swiss-born phytosociologist. On the other end of the argument was American ecologist Henry Gleason, who saw these groupings of plant species as a coincidence produced by the "fluctuation and fortuitous immigration of plants, and an equally fluctuating and va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Ornduff
Robert Ornduff (1932–2000) was an American botanist. He was Director of the University and Jepson Herbaria, Director of the University of California Botanical Garden, Executive Director of the Miller Institute for Basic Research in Science, and Chair of the (former) Department of Botany and Professor of Integrative Biology at the University of California at Berkeley. Botanist Phyllis M. Faber said of him following his death, "his extensive knowledge and love of the California flora remains unmatched." Robert Ornduff, Phyllis M. Faber, Todd Keeler-Wolf; 2003 revised ed.; Preface, p. x He was a specialist in the systematics of various plant groups in California, particularly the |
Polygonum Aviculare
''Polygonum aviculare'' or common knotgrass is a plant related to buckwheat and dock. It is also called prostrate knotweed, birdweed, pigweed and lowgrass. It is an annual found in fields and wasteland, with white flowers from June to October. It is widespread across many countries in temperate regions, apparently native to Eurasia, naturalized in temperate parts of the Southern Hemisphere. Description Common knotgrass is an annual, low-prostrate herb with semi-erect, branching stems, which forms patches up to about 2 m across as it matures. It has alternate linear-lanceolate leaves which are longer (7-15 mm) on the main stems than on the branches (3-5 mm). The whole plant is hairless and green, although it may appear mealy due to a powdery mildew, which can give the leaves a whitish appearance. The leaves fall early, especially on the main stem. The leaf stalks (petioles) are up to 5 mm long or sometimes absent. Above each leaf there is an ochrea, which is a translucent papery ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artemisia Austriaca
''Artemisia austriaca'' is a species of plant belonging to the family Asteraceae. Its native range is Europe to Western Siberia, and Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort .... References austriaca {{Anthemideae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forb
A forb or phorb is a herbaceous flowering plant that is not a graminoid (grass, sedge, or rush). The term is used in botany and in vegetation ecology especially in relation to grasslands and understory. Typically, these are eudicots without woody stems. Etymology The word ''forb'' is derived from Greek () 'pasture; fodder'. The Hellenic spelling ''phorb'' is sometimes used, and in older usage this sometimes includes graminids and other plants currently not regarded as forbs. Guilds Forbs are members of a guilda group of plant species with broadly similar growth forms. In certain contexts in ecology, guild membership may often be more important than the taxonomic relationships between organisms. In informal classification In addition to its use in ecology, the term "forb" may be used for subdividing popular guides to wildflowers, distinguishing them from other categories such as grasses, sedges, shrubs, and trees. Some examples of forbs are clovers, sunflowers, daylilie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carex Shreberi
''Carex'' is a vast genus of over 2,000 species of grass-like plants in the family Cyperaceae, commonly known as sedges (or seg, in older books). Other members of the family Cyperaceae are also called sedges, however those of genus ''Carex'' may be called true sedges, and it is the most species-rich genus in the family. The study of ''Carex'' is known as caricology. Description All species of ''Carex'' are perennial, although some species, such as '' C. bebbii'' and '' C. viridula'' can fruit in their first year of growth, and may not survive longer. They typically have rhizomes, stolons or short rootstocks, but some species grow in tufts (caespitose). The culm – the flower-bearing stalk – is unbranched and usually erect. It is usually distinctly triangular in section. The leaves of ''Carex'' comprise a blade, which extends away from the stalk, and a sheath, which encloses part of the stalk. The blade is normally long and flat, but may be folded, inrolled, channell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytocoenosis
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 phyto-sociology, such a unit is known as a phytocoenosis (or phytocoenose). 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 w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poa Bulbosa
''Poa bulbosa'' is a species of grass known by the common names bulbous bluegrass or bulbous meadow-grass. It is native to Eurasia and North Africa, but it is present practically worldwide as an introduced species. It is widespread in the United States and southern Canada. It was introduced to the eastern United States around 1906 and the western US in 1915 as a contaminant in shipments of alfalfa seed.Novak, S. J. & A. Y. Welfley. (1997)Genetic diversity in the introduced clonal grass ''Poa bulbosa'' (Bulbous bluegrass).''Northwest Science'' 71:4 271-80. It was intentionally planted on both the east and west coasts to control weeds and prevent erosion. Today it is a common grass across the continent and is a noxious weed in some areas. It is a sturdy, hardy, persistent, aggressive grass that easily outcompetes many other plants and becomes the dominant species in disturbed habitat types, such as overgrazed fields. This is an annual or perennial grass forming dense clumps up to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Festuca Sulcata
''Festuca rupicola'', the furrowed fescue, is a species of cool-season grass in the family Poaceae Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and species cultivate .... It is native to the warm-temperate Old World; from the Atlas Mountains of Africa, as well as France and much of central and eastern Europe through to Central Asia and on to Manchuria, and as far south as Saudi Arabia and Iran. A tussock-former, it is considered a typical dominant species of ancient species-rich grasslands. References rupicola Flora of Morocco Flora of Algeria Flora of France Flora of Middle Europe Flora of Southeastern Europe Flora of Eastern Europe Flora of West Siberia Flora of the Caucasus Flora of Central Asia Flora of Altai (region) Flora of Saudi Arabia Flora of Iran Flora of Afghanistan Fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steppes
In physical geography, a steppe () is an ecoregion characterized by grassland plains without closed forests except near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the tropical and subtropical grasslands, savannas, and shrublands biome * the temperate grasslands, savannas, and shrublands biome A steppe is usually covered with grass and shrubs, depending on the season and latitude. The term ''steppe climate'' denotes a semi-arid climate, which is encountered in regions too dry to support a forest, but not dry enough to be a desert. Steppes are usually characterized by a semi-arid or continental climate. Temperature extremes can be recorded in the summer of up to and in winter of down to . Besides this major seasonal difference, fluctuations between day and night are also significant: in both the highlands of Mongolia and northern Nevada, can be reached during the day with sub-freezing readings at night. Steppes average of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caucasus
The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, including the Greater Caucasus range, have conventionally been considered as a natural barrier between Europe and Asia, bisecting the Eurasian landmass. Mount Elbrus, Europe's highest mountain, is situated in the Western Caucasus area of Russia. On the southern side, the Lesser Caucasus includes the Javakheti Plateau and the Armenian highlands. The Caucasus is divided into the North Caucasus and South Caucasus, although the Western Caucasus also exists as a distinct geographic space within the North Caucasus. The Greater Caucasus mountain range in the north is mostly shared by Russia and Georgia as well as the northernmost parts of Azerbaijan. The Lesser Caucasus mountain range in the south is mostly located on the territory of sout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grassland
A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceous plant, herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on Earth and dominate the landscape worldwide. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands. They cover 31–69% of the Earth's land area. Definitions Included among the variety of definitions for grasslands are: * "...any plant community, including harvested forages, in which grasses and/or legumes make up the dominant vegetation." * "...terrestrial ecosystems dominated by herbaceous and shrub vegetation, and maintained by fire, grazing, drought and/or freezing temperatures." (Pilot Assessm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
