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Alisma × Bjoerkqvistii
''Alisma'' is a genus of flowering plants in the family Alismataceae, members of which are commonly known as water-plantains. The genus consists of aquatic plants with leaves either floating or submerged, found in a variety of still water habitats around the world (nearly worldwide). The flowers are hermaphrodite, and are arranged in panicles, racemes, or umbels. ''Alisma'' flowers have six stamens, numerous free carpels in a single whorl, each with 1 ovule, and subventral styles. The fruit is an achene with a short beak. The nineteenth century British art and social critic John Ruskin believed that the particular curve of the leaf-ribs of ''Alisma'' represented a model of ' divine proportion' and helped shape his theory of Gothic architecture. ("Patrick's leaf") is the Irish name for the water-plantain. It is reputed to ward off fairies. Water plantains are perennial plants. These herbs are usually emergent plants high. They have broad leaves that can be either tapered or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alisma Plantago-aquatica
''Alisma plantago-aquatica'', also known as European water-plantain, common water-plantain or mad-dog weed, is a perennial flowering plant, flowering aquatic plant widespread across most of Europe and Asia, and apparently spread elsewhere in both the Old World, Old and New World. Description ''Alisma plantago-aquatica'' is a hairless plant that grows in shallow water, consists of a fibrous root, several basal long stemmed leaves long, and a triangular plant stem, stem up to tall. It has branched inflorescence bearing numerous small flowers, across, with three round or slightly jagged, white or pale purple petals. The flowers open in the afternoon. There are three blunt green sepals and six stamens per flower. The carpels often exist as a flat single Whorl (botany), whorl. It flowers from June until August. The fruits appear as a ring of seeds inside each flower. Chemistry Chemical constituents of —rhizomes of ''Alisma orientale'' (syn. ''Alisma '' var. ''orientale'') as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden Ratio
In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their summation, sum to the larger of the two quantities. Expressed algebraically, for quantities and with , is in a golden ratio to if \frac = \frac = \varphi, where the Greek letter Phi (letter), phi ( or ) denotes the golden ratio. The constant satisfies the quadratic equation and is an irrational number with a value of The golden ratio was called the extreme and mean ratio by Euclid, and the divine proportion by Luca Pacioli; it also goes by other names. Mathematicians have studied the golden ratio's properties since antiquity. It is the ratio of a regular pentagon's diagonal to its side and thus appears in the Straightedge and compass construction, construction of the dodecahedron and icosahedron. A golden rectangle—that is, a rectangle with an aspect ratio of —may be cut into a square and a smaller rectangle with the same aspect ratio. The golden ratio has bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Africa
North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of the Western Sahara in the west, to Egypt and Sudan's Red Sea coast in the east. The most common definition for the region's boundaries includes Algeria, Egypt, Libya, Morocco, Tunisia, and Western Sahara, the territory territorial dispute, disputed between Morocco and the list of states with limited recognition, partially recognized Sahrawi Arab Democratic Republic. The United Nations’ definition includes all these countries as well as Sudan. The African Union defines the region similarly, only differing from the UN in excluding the Sudan and including Mauritania. The Sahel, south of the Sahara, Sahara Desert, can be considered as the southern boundary of North Africa. North Africa includes the Spanish cities of Ceuta and Melilla, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandre Louis Simon Lejeune
Alexandre Louis Simon Lejeune (23 December 1779 in Verviers – 28 December 1858 in Verviers) was a physician and botanist. In 1801 he entered the school of medicine in Paris, but was subsequently forced to abandon his studies due to military conscription. After finishing his military duties in late 1804, he relocated to Ensival as a physician. Three years later, he settled permanently in his hometown of Verviers. With Richard Courtois (1806–1835), he was co-author of "Compendium florae belgicae". He was a mentor to Marie-Anne Libert, who he introduced to Augustin Pyramis de Candolle. Libert named the genus ''Lejeunea'' (family Lejeuneaceae) in Lejeune's honor in 1820. Botanical works * ''Flore des environs de Spa'', 1811 - Flora native to the environs of Spa. * ''Revue de la flore des environs de Spa'', 1824 - Review of flora native to the environs of Spa. * ''De Libertia, novo graminum genere, Commentatio'' 1825 - On the genus ''Libertia''. * ''Compendium florae belgicae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alisma Gramineum
''Alisma gramineum'' is a small aquatic plant in the water-plantain family. It has several common names including narrowleaf water-plantain, ribbonleaf water-plantain or ribbon-leaved water-plantain, and grass-leaved water-plantain. It grows in mud or submerged in shallow fresh or brackish water in marshy areas. Description The leaves and tiny purple-tinted white flowers may be submersed or not. When the flowers grow underwater they are cleistogamous, meaning they stay closed and self-pollinate. When the flowers grow above water they open. The leaves above the surface are stiff and wide, but submerged leaves are ribbon-like. The fruit is a ring of dry nutlets. Reproduction is by seed or from division of the corm. Distribution and habitat ''Alisma gramineum'' is widespread across temperate and subarctic portions of Asia and Europe and North Africa from France and Libya to China and Yakutsk. It is reported from much of Canada from British Columbia to Quebec, as well as most of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asia
Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilisations. Its 4.7 billion people constitute roughly 60% of the world's population. Asia shares the landmass of Eurasia with Europe, and of Afro-Eurasia with both Europe and Africa. In general terms, it is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean, and on the north by the Arctic Ocean. The border of Asia with Europe is a social constructionism, historical and cultural construct, as there is no clear physical and geographical separation between them. A commonly accepted division places Asia to the east of the Suez Canal separating it from Africa; and to the east of the Turkish straits, the Ural Mountains an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alisma Canaliculatum
''Alisma canaliculatum'', commonly known as channelled water plantain, is a species of plants in the Alismataceae. It is native to Japan, Korea, the Ryukyu Islands, Taiwan, the Kuril Islands, and China (Anhui, Fujian, Guizhou, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shandong, Sichuan, Zhejiang). ''Alisma canaliculatum'' is a perennial herb with tubers up to 3 cm across. Leaves are lanceolate, up to 50 cm long. Flowers are white, borne in a branching panicle. References External links Plants For a Future Alisma, canaliculatum Freshwater plants Flora of Zhejiang Flora of Taiwan Flora of Sichuan Flora of Shandong Flora of Jiangxi Flora of Jiangsu Flora of Hunan Flora of Hubei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders of Russia, land borders with fourteen countries. Russia is the List of European countries by population, most populous country in Europe and the List of countries and dependencies by population, ninth-most populous country in the world. It is a Urbanization by sovereign state, highly urbanised country, with sixteen of its urban areas having more than 1 million inhabitants. Moscow, the List of metropolitan areas in Europe, most populous metropolitan area in Europe, is the capital and List of cities and towns in Russia by population, largest city of Russia, while Saint Petersburg is its second-largest city and Society and culture in Saint Petersburg, cultural centre. Human settlement on the territory of modern Russia dates back to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alisma × Bjoerkqvistii
''Alisma'' is a genus of flowering plants in the family Alismataceae, members of which are commonly known as water-plantains. The genus consists of aquatic plants with leaves either floating or submerged, found in a variety of still water habitats around the world (nearly worldwide). The flowers are hermaphrodite, and are arranged in panicles, racemes, or umbels. ''Alisma'' flowers have six stamens, numerous free carpels in a single whorl, each with 1 ovule, and subventral styles. The fruit is an achene with a short beak. The nineteenth century British art and social critic John Ruskin believed that the particular curve of the leaf-ribs of ''Alisma'' represented a model of ' divine proportion' and helped shape his theory of Gothic architecture. ("Patrick's leaf") is the Irish name for the water-plantain. It is reputed to ward off fairies. Water plantains are perennial plants. These herbs are usually emergent plants high. They have broad leaves that can be either tapered or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swamp
A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in creating this environment. Swamps vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water, or seawater. Freshwater swamps form along large rivers or lakes where they are critically dependent upon rainwater and seasonal flooding to maintain natural water level fluctuations.Hughes, F.M.R. (ed.). 2003. The Flooded Forest: Guidance for policy makers and river managers in Europe on the restoration of floodplain forests. FLOBAR2, Department of Geography, University of Cambridge, Cambridge, UK. 96 p. Saltwater swamps are found along tropical and subtropical coastlines. Some swamps have hammock (ecology), hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marsh
In ecology, a marsh is a wetland that is dominated by herbaceous plants rather than by woody plants.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p More in general, the word can be used for any low-lying and seasonally waterlogged terrain. In Europe and in agricultural literature low-lying meadows that require draining and embanked polderlands are also referred to as marshes or marshland. Marshes can often be found at the edges of lakes and streams, where they form a transition between the aquatic and terrestrial ecosystems. They are often dominated by grasses, rushes or reeds. If woody plants are present they tend to be low-growing shrubs, and the marsh is sometimes called a carr. This form of vegetation is what differentiates marshes from other types of wetland such as swamps, which are dominated by trees, and mires, which are wetlands that have accumulated deposits of acidic peat. Marshes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
