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Chigua Bernalii
''Chigua'' is a genus of cycads in the family Zamiaceae containing two species, endemic to small areas in northwestern Colombia. Described by botanist Dennis Stevenson in 1990, it is the most recently named genus, and the name refers to a Spanish transliteration of the common name given to cycads by the indigenous peoples of Colombia. The species are found in wet lowland rainforests at 100–200 m altitude. Both species are listed as Critically Endangered by the IUCN Red List. The whole genus is listed under CITES Appendix I / EU Annex A, and CITES prohibits international trade in specimens of these species except when the purpose of the import is not commercial, for instance for scientific research. Plants have a subterranean globose stem. The leaves emerge singly and are straight, oblong, and pinnately compound. The petiole and rachis have spines. leaflets are opposite, lanceolate, and jointed at the base. They have a toothed margin with a distinct midrib and forking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dennis William Stevenson
Dennis or Denis is a first or last name from the Greco-Roman name Dionysius, via one of the Christian saints named Dionysius. The name came from Dionysus, the Greek god of ecstatic states, particularly those produced by wine, which is sometimes said to be derived from the Greek Dios (Διός, "of Zeus") and Nysos or Nysa (Νῦσα), where the young god was raised. Dionysus (or Dionysos; also known as Bacchus in Roman mythology and associated with the Italic Liber), the Thracian god of wine, represents not only the intoxicating power of wine, but also its social and beneficent influences. He is viewed as the promoter of civilization, a lawgiver, and lover of peace—as well as the patron deity of both agriculture and the theater. Dionysus is a god of mystery religious rites, such as those practiced in honor of Demeter and Persephone at Eleusis near Athens. In the Thracian mysteries, he wears the "bassaris" or fox-skin, symbolizing new life. (See also Maenads.) A mediaeval ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. Most leaves are flattened and have distinct upper (adaxial) and lower ( abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll that is essential for photosynthesis as it absorbs light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic viability of investing in the equipment, labor, and energy required to extract, refine and transport the materials found at the mine to manufacturers who can use the material. Ores recovered by mining include metals, coal, oil shale, gemstones, limestone, chalk, dimension stone, rock salt, potash, gravel, and clay. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grazing
In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to roam around and consume wild vegetations in order to convert the otherwise indigestible (by human gut) cellulose within grass and other forages into meat, milk, wool and other animal products, often on land unsuitable for arable farming. Farmers may employ many different strategies of grazing for optimum production: grazing may be continuous, seasonal, or rotational within a grazing period. Longer rotations are found in ley farming, alternating arable and fodder crops; in rest rotation, deferred rotation, and mob grazing, giving grasses a longer time to recover or leaving land fallow. Patch-burn sets up a rotation of fresh grass after burning with two years of rest. Conservation grazing proposes to use grazing animals to improve the biodiversity of a site, but studies show that the greatest benefit to biodiversity comes from removing grazing animals from the landscape. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francis Pennell
Francis Whittier Pennell (4 August 1886 – 3 February 1952) was an American botanist best known for his studies of the Scrophulariaceae. Employed by the New York Botanical Garden and then by the Academy of Natural Sciences of Philadelphia, he carried out botanical research in both North America and South America. Life Pennell was born to a Quaker family on their farm near Wawa, Pennsylvania. Considered delicate by his family, he was excused from farm chores, which engendered in him a lifelong fear of water and incapacity with mechanical devices. Pennell was educated at Westtown School and then at the University of Pennsylvania, from which he received a B.S. in 1911 and a Ph.D. in 1913. Encouraged by John M. Macfarlane, the head of the botany department, Pennell wrote his doctoral thesis on the Scrophulariaceae (as then circumscribed), a group on which he was to become a world authority. From 1914 to 1921, Pennell was a member of the staff at the New York Botanical Gard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamia
''Zamia'' is a genus of cycad of the family Zamiaceae, native to North America from the United States (in Georgia and Florida) throughout the West Indies, Central America, and South America as far south as Bolivia. The genus is considered to be the most ecologically and morphologically diverse cycads, and is estimated to have originated about 68.3 million years ago. Description The genus comprises deciduous shrubs with aerial or subterranean circular stems, often superficially resembling palms. They produce spirally arranged, pinnate leaves which are pubescent, at least when young, having branched and simple, transparent and coloured hairs. The articulated leaflets lack a midrib, and are broad with subparallel dichotomous venation. Lower leaflets are not reduced to spines, though the petioles often have prickles. The emerging leaves of many ''Zamia'' species are striking, some emerging with a reddish or bronze cast ('' Z. roeslii'' being an example). ''Zamia picta'' is even more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peduncle (botany)
In botany, a peduncle is a stalk supporting an inflorescence or a solitary flower, or, after fecundation, an infructescence or a solitary fruit. The peduncle sometimes has bracts (a type of cataphylls) at nodes. The main axis of an inflorescence above the peduncle is the rachis. There are no flowers on the peduncle but there are flowers on the rachis. When a peduncle arises from the ground level, either from a compressed aerial stem or from a subterranean stem (rhizome, tuber, bulb, corm), with few or no bracts except the part near the rachis or receptacle, it is referred to as a scape. The acorns of the pedunculate oak are borne on a long peduncle, hence the name of the tree. See also *Pedicel (botany) *Scape (botany) In botany, a scape is a peduncle arising from a subterranean or very compressed stem, with the lower internodes very long and hence few or no bracts except the part near the rachis or receptacle. Typically it takes the form of a long, leafles ... Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporophyll
A sporophyll is a leaf that bears sporangia. Both microphylls and megaphylls can be sporophylls. In heterosporous plants, sporophylls (whether they are microphylls or megaphylls) bear either megasporangia and thus are called megasporophylls, or microsporangia and are called microsporophylls. The overlap of the prefixes and roots makes these terms a particularly confusing subset of botanical nomenclature. Sporophylls vary greatly in appearance and structure, and may or may not look similar to sterile leaves. Plants that produce sporophylls include: ''Alaria esculenta'', a brown alga which shows sporophylls attached near the base of the alga.Dickson, Carola I. 1963. ''British Seaweeds''. The Kew Series. Lycophytes, where sporophylls may be aggregated into strobili (''Selaginella'' and some ''Lycopodium'' and related genera) or distributed singly among sterile leaves (''Huperzia''). Sporangia are borne in the axil or on the adaxial surface of the sporophyll. In heterosporous members ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midrib
This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology. For other related terms, see Glossary of phytopathology, Glossary of lichen terms, and List of Latin and Greek words commonly used in systematic names. A B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaflet (botany)
A leaflet (occasionally called foliole) in botany is a leaf-like part of a compound leaf. Though it resembles an entire leaf, a leaflet is not borne on a main plant stem or branch, as a leaf is, but rather on a leaf, petiole or a branch of the leaf. Compound leaves are common in many plant families and they differ widely in morphology (biology), morphology. The two main classes of compound leaf morphology are Leaf shape, palmate and pinnate. For example, a ''Cannabis, hemp'' plant has palmate compound leaves, whereas some species of ''Acacia sensu lato, Acacia'' have pinnate leaves. The ultimate free division (or leaflet) of a compound leaf, or a pinnate subdivision of a multipinnate leaf is called a pinnule or pinnula. Image:Ветвь акации.jpg, Pinnate leaf of a Fabaceae, legume with 10 leaflets Image:Mimosa Pudica.gif, ''Mimosa pudica'' folding leaflets inward. See also * Compound leaf References Plant morphology {{botany-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rachis
In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachis'' usually forms the supporting axis of the body and is then called the spine or vertebral column. ''Rachis'' can also mean the central shaft of pennaceous feathers. In the gonad of the invertebrate nematode '' Caenorhabditis elegans'', a rachis is the central cell-free core or axis of the gonadal arm of both adult males and hermaphrodites where the germ cells have achieved pachytene and are attached to the walls of the gonadal tube. The rachis is filled with cytoplasm. In botany In plants, a rachis is the main axis of a compound structure. It can be the main stem of a compound leaf, such as in ''Acacia'' or ferns, or the main, flower-bearing portion of an inflorescence above a supporting peduncle. Where it subdivides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CITES Appendix I
CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of international trade. It was drafted as a result of a resolution adopted in 1963 at a meeting of members of the International Union for Conservation of Nature (IUCN). The convention was opened for signature in 1973 and CITES entered into force on 1 July 1975. Its aim is to ensure that international trade (import/export) in specimens of animals and plants included under CITES, does not threaten the survival of the species in the wild. This is achieved via a system of permits and certificates. CITES affords varying degrees of protection to more than 38,000 species. , Secretary-General of CITES is Ivonne Higuero. Background CITES is one of the largest and oldest conservation and sustainable use agreements in existence. There are three working langu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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