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Juncus
''Juncus'' is a genus of monocotyledonous flowering plants, commonly known as rushes. It is the largest genus in the family Juncaceae, containing around 300 species. Description Rushes of the genus ''Juncus'' are herbaceous plants that superficially resemble grasses or sedges. They have historically received little attention from botanists; in his 1819 monograph, James Ebenezer Bicheno described the genus as "obscure and uninviting". The form of the flower differentiates rushes from grasses or sedges. The flowers of ''Juncus'' comprise five whorls of floral parts: three sepals, three petals (or, taken together, six tepals), two to six stamens (in two whorls) and a stigma with three lobes. The stems are round in cross-section, unlike those of sedges, which are typically somewhat triangular in cross-section. In ''Juncus'' section ''Juncotypus'' (formerly called ''Juncus'' subg. ''Genuini''), which contains some of the most widespread and familiar species, the leaves are reduced t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juncus Acutus
''Juncus acutus'', the spiny rush, sharp rush or sharp-pointed rush, is a flowering plant in the monocot family Juncaceae found throughout the Americas, Northern and Southern Africa, Western and Southern Europe and West Asia. It grows in salt marshes and on dunes and is reliable for reducing erosion rates. In some countries like Australia it is considered to be an invasive weed and the spines harmful to young children. Synonyms *''Juncus acutus'' ssp. ''leopoldii'' (Parl.) Snog. -- Leopold's rush *''Juncus acutus'' L. var. ''sphaerocarpus'' Engelm *''Juncus acutus'' L. subsp. ''acutus'' *''Juncus spinosus'' Forssk *''Juncus acutus'' ssp. ''leopoldii'' also known as ''Leopold's rush'' is a native of Arizona, California, Georgia and Nevada. *''Juncus acutus'' L. var. ''conglobatus'' Trautv *''Juncus acutus'' L. var. ''decompositus'' Guss *''Juncus acutus'' L. var. ''longibracteatus'' Buchenau Description ''Juncus acutus'' is a brown and green " tussocky" perennial that can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juncaceae
Juncaceae is a family of flowering plants, commonly known as the rush family. It consists of 8 genera and about 464 known species of slow-growing, rhizomatous, herbaceous monocotyledonous plants that may superficially resemble grasses and sedges. They often grow on infertile soils in a wide range of moisture conditions. The best-known and largest genus is ''Juncus''. Most of the ''Juncus'' species grow exclusively in wetland habitats. A few rushes, such as '' Juncus bufonius'' are annuals, but most are perennials. Description The leaves are evergreen and well-developed in a basal aggregation on an erect stem. They are alternate and tristichous (i.e., with three rows of leaves up the stem, each row of leaves arising one-third of the way around the stem from the previous leaf). Only in the genus '' Distichia'' are the leaves distichous. The rushes of the genus ''Juncus'' have flat, hairless leaves or cylindrical leaves. The leaves of the wood-rushes of the genus ''Luzula' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juncus Conglomeratus
''Juncus conglomeratus'', known commonly as compact rush, is a perennial, herbaceous flowering plant species in the rush family Juncaceae.The Lowland Grassland Management Handbook 2nd edition, A Crofts and R G Jefferson (eds) , 1999 In the British Isles
The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...
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Sedge
The Cyperaceae are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large, with some 5,500 known species described in about 90 genera, the largest being the "true sedges" genus ''Carex'' with over 2,000 species. These species are widely distributed, with the centers of diversity for the group occurring in tropical Asia and tropical South America. While sedges may be found growing in almost all environments, many are associated with wetlands, or with poor soils. Ecological communities dominated by sedges are known as sedgelands or sedge meadows. Some species superficially resemble the closely related rushes and the more distantly related grasses. Features distinguishing members of the sedge family from grasses or rushes are stems with triangular cross-sections (with occasional exceptions, a notable example being the tule which has a round cross-section) and leaves that are spirally arranged in three ranks. In comparison, g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montane
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial factor in shaping plant community, biodiversity, metabolic processes and ecosystem dynamics for montane ecosystems. Dense montane forests are common at moderate elevations, due to moderate temperatures and high rainfall. At higher elevations, the climate is harsher, with lower temperatures and higher winds, preventing the growth of trees and causing the plant community to transition to montane grasslands, shrublands or alpine tundra. Due to the unique climate conditions of montane ecosystems, they contain increased numbers of endemic species. Montane ecosystems also exhibit variation in ecosystem services, which include carbon storage and water supply. Life zones As elevation increases, the climate becomes cooler, due to a decrease in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmopolitan Distribution
In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The extreme opposite of a cosmopolitan species is an endemic one, being found only in a single geographical location. Qualification The caveat “in appropriate habitat” is used to qualify the term "cosmopolitan distribution", excluding in most instances polar regions, extreme altitudes, oceans, deserts, or small, isolated islands. For example, the housefly is highly cosmopolitan, yet is neither oceanic nor polar in its distribution. Related terms and concepts The term pandemism also is in use, but not all authors are consistent in the sense in which they use the term; some speak of pandemism mainly in referring to diseases and pandemics, and some as a term intermediate between endemism and cosmopolitanism, in effect regarding pandemism as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telopea (journal)
''Telopea'' is a fully open-access, online, peer-reviewed scientific journal that rapidly publishes original research on plant systematics, with broad content that covers Australia and the Asia-Pacific region. The journal was established in 1975 and is published by the National Herbarium of New South Wales, Royal Botanic Gardens & Domain Trust. As from Volume 9, part 1, 2000, full text of papers is available electronically in pdf format. It is named for the genus ''Telopea'', commonly known as waratah Waratah (''Telopea'') is an Australian-endemic genus of five species of large shrubs or small trees, native to the southeastern parts of Australia (New South Wales, Victoria, and Tasmania). The best-known species in this genus is ''Telopea speci ...s. The forerunner of ''Telopea'' was ''Contributions from the New South Wales National Herbarium'' which was first published in July 1939 as Volume 1(1). Publication was suspended between 1941 and resumed in 1948 with the publication of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture. Typically, they also look different from the parts of the flower, such as the petals or sepals. A plant having bracts is referred to as bracteate or bracteolate, while one that lacks them is referred to as ebracteate and ebracteolate, without bracts. Variants Some bracts are brightly-coloured and serve the function of attracting pollinators, either together with the perianth or instead of it. Examples of this type of bract include those of ''Euphorbia pulcherrima'' (poinsettia) and ''Bougainvillea'': both of these have large colourful bracts surrounding much smaller, less colourful flowers. In grasses, each floret (flower) is enclosed in a pair of papery bracts, called the lemma (lower bract) and p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stigma (botany)
The stigma () is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. Description The stigma, together with the style and ovary (typically called the stigma-style-ovary system) comprises the pistil, which is part of the gynoecium or female reproductive organ of a plant. The stigma itself forms the distal portion of the style, or stylodia, and is composed of , the cells of which are receptive to pollen. These may be restricted to the apex of the style or, especially in wind pollinated species, cover a wide surface. The stigma receives pollen and it is on the stigma that the pollen grain germinates. Often sticky, the stigma is adapted in various ways to catch and trap pollen with various hairs, flaps, or sculpturings. The pollen may be captured from the air (wind-borne pollen, anemophily), from visiting insects or other animals ( biotic pollination), or in rare cases from surrounding water (hydrophily). Stigma can vary from long and sle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamen
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament and an anther which contains ''sporangium, microsporangia''. Most commonly anthers are two-lobed and are attached to the filament either at the base or in the middle area of the anther. The sterile tissue between the lobes is called the connective, an extension of the filament containing conducting strands. It can be seen as an extension on the dorsal side of the anther. A pollen grain develops from a microspore in the microsporangium and contains the male gametophyte. The stamens in a flower are collectively called the androecium. The androecium can consist of as few as one-half stamen (i.e. a single locule) as in ''Canna (plant), Canna'' species or as many as 3,482 stamens which have been counted in the saguaro (''Carnegiea gigantea'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (botany)
In botany, a whorl or verticil is an arrangement of leaves, sepals, petals, stamens, or carpels that radiate from a single point and surround or wrap around the stem or stalk. A leaf whorl consists of at least three elements; a pair of opposite leaves is not called a whorl. For leaves to grow in whorls is fairly rare except in plant species with very short internodes and some other genera (Galium, Nerium, Elodea etc.). Leaf whorls occur in some trees such as ''Brabejum stellatifolium'' and other species in the family Proteaceae (e.g., in the genus ''Banksia''). In plants such as these, crowded internodes within the leaf whorls alternate with long internodes between the whorls. The morphology of most flowers (called cyclic flowers) is based on four types of whorls: # The calyx: zero or more whorls of sepals at the base # The corolla: zero or more whorls of petals above the calyx # The androecium: zero or more whorls of stamens, each comprising a filament and an anther # The gyn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
