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Kobresia Simpliciuscula
''Carex simpliciuscula'' is a species of sedge known by the common names false sedge, simple bog sedge and simple kobresia. It has a circumpolar distribution, occurring throughout the northern latitudes of the Northern Hemisphere.''Kobresia simpliciuscula''. The Nature Conservancy. This perennial plant forms tufts of several triangular stems reaching up to 50 centimeters in height. It has short s. The leaves are up to 20 centimeters long. The contains up to 12 spikes of flowers. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Göran Wahlenberg
Georg (Göran) Wahlenberg (1 October 1780 – 22 March 1851) was a Swedish naturalist. He was born in Kroppa, Värmland County. Wahlenberg matriculated at Uppsala University in 1792, received his doctorate in Medicine in 1806, was appointed ''botanices demonstrator'' in 1814, and professor of medicine and botany in 1829, succeeding Carl Peter Thunberg. He was the last holder of the undivided chair that in the previous century had been held by Linnaeus. After his death in 1851, the chair was divided into more delimited professorships, and botany became the main duty of the borgströmian professorship, at the time held by Elias Fries. Wahlenberg made his main work in the field of plant geography and published, among other things the ''Flora lapponica'' (1812) and other works on the plant world of northernmost Sweden. He was among the first major scholars to contribute to the plant taxonomy and geography of the High Tatras in the Habsburg monarchy where he carried out re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kenneth Kent Mackenzie
Kenneth Kent Mackenzie (1877–1934) was a lawyer and amateur botanist who wrote extensively on the genus ''Carex'' in North America. Taxa Cyperaceae He described the following taxa in the family Cyperaceae (sedges); alternative combinations are indented. *'' Carex abramsii'' Mack. *'' Carex abrupta'' Mack. *'' Carex abscondita'' Mack. *'' Carex acutinella'' Mack. *'' Carex agglomerata'' Mack. *'' Carex aggregata'' Mack. := '' Carex sparganioides'' var. ''aggregata'' (Mack.) Gleason *'' Carex agrostoides'' Mack. *'' Carex albonigra'' Mack. *'' Carex allegheniensis'' Mack. *'' Carex amphigena'' Mack. *'' Carex amplectens'' Mack. *'' Carex leersii'' var. ''angustata'' (J.Carey) Mack. *'' Carex angustior'' Mack. *'' Carex arctaeformis'' Mack. *'' Carex arctiformis'' Mack. := '' Carex canescens'' subsp. ''arctiformis'' (Mack.) Calder & Roy L.Taylor *'' Carex artitecta'' Mack. *'' Carex atrosquama'' Mack. := '' Carex atrata'' subsp. ''atrosquama'' (Mack.) Hultén := '' Carex atrata'' v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyperaceae
The Cyperaceae () are a family of graminoid (grass-like), monocotyledonous flowering plants known as wikt:sedge, sedges. The family (biology), family is large; botanists have species description, described some 5,500 known species in about 90 genus, generathe largest being the "true wikt:sedge, sedges" (genus ''Carex''), with over 2,000 species. Distribution Cyperaceae species are widely distributed with the centers of diversity for the group occurring in tropical Asia and tropical South America. While sedges grow in almost all environments, many thrive in wetlands or in poor soils. Community (ecology), Ecological communities dominated by sedges are known as s or as sedge meadows. Classification Some species superficially resemble the closely related Juncaceae , 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 be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latitude
In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at the south pole to 90° at the north pole, with 0° at the Equator. Parallel (latitude), Lines of constant latitude, or ''parallels'', run east-west as circles parallel to the equator. Latitude and longitude are used together as a coordinate pair to specify a location on the surface of the Earth. On its own, the term "latitude" normally refers to the ''geodetic latitude'' as defined below. Briefly, the geodetic latitude of a point is the angle formed between the vector perpendicular (or ''Normal (geometry), normal'') to the ellipsoidal surface from the point, and the equatorial plane, plane of the equator. Background Two levels of abstraction are employed in the definitions of latitude and longitude. In the first step the physical surface i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizome
In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow horizontally. The rhizome also retains the ability to allow new shoots to grow upwards. A rhizome is the main stem of the plant that runs typically underground and horizontally to the soil surface. Rhizomes have nodes and internodes and auxiliary buds. Roots do not have nodes and internodes and have a root cap terminating their ends. In general, rhizomes have short internodes, send out roots from the bottom of the nodes, and generate new upward-growing shoots from the top of the nodes. A stolon is similar to a rhizome, but stolon sprouts from an existing stem having long internodes and generating new shoots at the ends, they are often also called runners such as in the strawberry plant. A stem tuber is a thickene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis (Peduncle (botany), peduncle) and by the timing of its flowering (determinate and indeterminate). Morphology (biology), Morphologically, an inflorescence is the modified part of the Shoot (botany), shoot of spermatophyte, seed plants where flowers are formed on the axis of a plant. The modifications can involve the length and the nature of the internode (botany), internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern. General characteristics Inflorescences are described by many different charact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germination
Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ferns, bacteria, and the growth of the pollen tube from the pollen grain of a seed plant. Seed plants Germination is usually the growth of a plant contained within a seed resulting in the formation of the seedling. It is also the process of reactivation of metabolic machinery of the seed resulting in the emergence of radicle and plumule. The seed of a vascular plant is a small package produced in a fruit or cone after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Dormant seeds are viable seeds that do not germinate because they require specific internal or environmental stimuli to resume growth. Und ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tundra
In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic, Antarctic. Tundra vegetation is composed of dwarf shrubs, Cyperaceae, sedges, Poaceae, grasses, mosses, and lichens. Scattered trees grow in some tundra regions. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline. The tundra soil is rich in nitrogen and phosphorus. The soil also contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide in the permafrost, making the tundra soil a carbon sink. As global warming heats the ecosystem and causes soil thawing, the permafrost carbon cycle accelerates and releases much of these soil-contained greenhouse gases into the atmosphere, creating Climate change feedback, a feedback cycle t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpine Climate
Alpine climate is the typical climate for elevations above the tree line, where trees fail to grow due to cold. This climate is also referred to as a mountain climate or highland climate. Definition There are multiple definitions of alpine climate. In the Köppen climate classification, the alpine and mountain climates are part of group ''E'', along with the polar climate, where no month has a mean temperature higher than . According to the Holdridge life zone system, there are two mountain climates which prevent tree growth : a) the alpine climate, which occurs when the mean biotemperature of a location is between . The alpine climate in Holdridge system is roughly equivalent to the warmest tundra climates (ET) in the Köppen system. b) the alvar climate, the coldest mountain climate since the biotemperature is between 0 °C and 1.5 °C (biotemperature can never be below 0 °C). It corresponds more or less to the coldest tundra climates and to the ice cap cli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcareous
Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcareous'' is used as an adjectival term applied to anatomical structures which are made primarily of calcium carbonate, in animals such as gastropods, i.e., snails, specifically in relation to such structures as the operculum (gastropod), operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate Test (biology), tests of, often, more-or-less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests. The molluscs are calcareous organisms, as are the Calcarea, calcareous sponges (Calcarea), that have spicules which are made of calcium carbonate. Additionally, reef-building corals, or Scleractinia, are calcareous organisms that form their rigid skeletal structure th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science), crystal forms of calcium carbonate . Limestone forms when these minerals Precipitation (chemistry), precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly Dolomite (rock), dolomite, a closely related rock, which contains a high percentage of the mineral Dolomite (mine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carex
''Carex'' is a vast genus of over 2,000 species of grass-like plants in the family (biology), 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 plant, perennial, although some species, such as ''Carex bebbii, C. bebbii'' and ''Carex viridula, 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 (botany), culm – the flower-bearing stalk – is unbranched and usually erect. It is usually distinctly triangular in section. The leaf, leaves of ''Carex'' comprise a blade, which extends away from the stalk, and a sheath, which encloses part of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
