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Cetraria Fallax
''Cetraria'' is a genus of fruticose lichens that associate with green algae as photobionts. Most species are found at high latitudes, occurring on sand or heath, and are characterised by their "strap-like" form with spiny edges. The lobes can range from narrow and linear to broader and flattened, often forming loose or densely packed cushions. Their distinctive spiny margins serve both a defensive role and aid in vegetative reproduction through fragmentation. The genus was created by Erik Acharius in 1803 and belongs to the large family Parmeliaceae. While originally a species-rich genus, taxonomic revisions since the 1960s have split many species into new genera, though the exact circumscription remains debated among lichenologists. Several ''Cetraria'' species have cultural and economic importance, particularly '' C. islandica'' (Iceland moss), which has been widely used in European traditional medicine for treating digestive and respiratory ailments. This species was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetraria Islandica
''Cetraria islandica'', also known as true Iceland lichen or Iceland moss, is an Arctic-alpine lichen whose erect or upright, leaflike habit gives it the appearance of a moss, where its name likely comes from. Description It is often of a pale chestnut color, but varies considerably, being sometimes almost entirely grayish-white; and grows to a height of from , the branches being channeled into flattened lobes with fringed edges. Chemistry In commerce it is a light-gray harsh cartilaginous body, almost colorless, and tastes slightly bitter. It contains about 70% of lichenin or lichen-starch, a polymeric carbohydrate compound isomeric with common starch. It also yields a peculiar modification of chlorophyll (called ''thallochlor''), fumaric acid, lichenostearic acid, and cetraric acid (which gives it the bitter taste). It also contains lichesterinic acid and protolichesterinic acids. Distribution and habitat It grows abundantly in the mountainous regions of northern cou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Famine Food
A famine food or poverty food is any inexpensive or ready available food used to nourish people in times of hunger and starvation, whether caused by extreme poverty, such as during economic depression or war, or by natural disasters such as drought. Foods associated with famine need not be nutritionally deficient, or unsavory. People who eat famine food in large quantity over a long period may become averse to it over time. In times of relative affluence, these foods may become the targets of social stigma and rejection. For example, some cultures that consider cats and dogs to be taboo foods may have historically consumed them during times of famine. The characterization of some foodstuffs as "famine" or "poverty" food can be social. For example, lobster and other crustaceans have been considered poverty food in some societies and luxury food in others, depending on the period and situation. Examples Several foodstuffs have been strongly associated with famine, war, or ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetraria Nivalis
''Cetraria'' is a genus of fruticose lichens that associate with green algae as photobionts. Most species are found at high latitudes, occurring on sand or heath, and are characterised by their "strap-like" form with spiny edges. The lobes can range from narrow and linear to broader and flattened, often forming loose or densely packed cushions. Their distinctive spiny margins serve both a defensive role and aid in vegetative reproduction through fragmentation. The genus was created by Erik Acharius in 1803 and belongs to the large family Parmeliaceae. While originally a species-rich genus, taxonomic revisions since the 1960s have split many species into new genera, though the exact circumscription remains debated among lichenologists. Several ''Cetraria'' species have cultural and economic importance, particularly '' C. islandica'' (Iceland moss), which has been widely used in European traditional medicine for treating digestive and respiratory ailments. This species was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Species
In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological Type (biology), type wiktionary:en:specimen, specimen (or specimens). Article 67.1 A similar concept is used for suprageneric groups and called a type genus. In botanical nomenclature, these terms have no formal standing under the International Code of Nomenclature for algae, fungi, and plants, code of nomenclature, but are sometimes borrowed from zoological nomenclature. In botany, the type of a genus name is a specimen (or, rarely, an illustration) which is also the type of a species name. The species name with that type can also be referred to as the type of the genus name. Names of genus and family ranks, the various subdivisions of those ranks, and some higher-rank names based on genus names, have suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peltidea
''Peltigera'' is a genus of approximately 100 species of foliose lichens in the family Peltigeraceae. Commonly known as the dog or pelt lichens, species of ''Peltigera'' are often terricolous (growing on soil), but can also occur on moss, trees, rocks, and many other in many parts of the world. Most species of ''Peltigera'' have the cyanobacterium ''Nostoc'' as the dominant photobiont but some have the algae ''Coccomyxa.'' The presence of both a green alga and a cyanobacterium makes some tripartite; in this case they show cephalodium growths containing the third partner, ''Nostoc''. Because of their ability to fix nitrogen from the atmosphere, such lichens are influential in soil composition and generation. Description Species of ''Peltigera'' are foliose, with broad lobed thalli. Although the size of the thalli is variable and species-dependent, in some species the thalli can grow quite large, up to 30 cm in diameter.Vitikainen O. (1994). (1998). Taxonomic notes on neot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parmelia (fungus)
''Parmelia'' is a genus of medium to large foliose lichen, foliose (leafy) lichens.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, It has a global distribution, extending from the ArcticSkult H (1985) A New Subspecies of ''Parmelia omphalodes'' Ascomycetes Described from the Arctic. Annales Botanici Fennici 22, 201-6. to the Antarctic continentD.C. Lindsay (1973) Notes on Antarctic lichens: IV. The genera ''Cetraria'' Hoffm., ''Hypogymnia'' (Nyl.) Nyl., ''Menegazzia'' Massal, ''Parmelia'' Ach. and ''Platismatia'' Culb. et Culb. British Antarctic Survey Bulletin 36, 105-114. but concentrated in temperate regions. There are about 40 species in ''Parmelia''. In recent decades, the once large genus ''Parmelia'' has been divided into a number of smaller genera according to thallus (tissue), thallus morphology and phylogenetic relatedness. It is a foliaceous lichen, resembling a leaf in shape. The ends of the leaf-like lobes are often squarish-tippe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apothecia
An ascocarp, or ascoma (: ascomata), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are most commonly bowl-shaped (apothecia) but may take on a spherical or flask-like form that has a pore opening to release spores (perithecia) or no opening (cleistothecia). Classification The ascocarp is classified according to its placement (in ways not fundamental to the basic taxonomy). It is called ''epigeous'' if it grows above ground, as with the morels, while underground ascocarps, such as truffles, are termed ''hypogeous''. The structure enclosing the hymenium is divided into the types described below (apothecium, cleistothecium, etc.) and this character ''is'' important for the taxonomic classification of the fungus. Apothecia can be relatively large and fleshy, whereas the others are microscopic—about the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Plantarum
' (Latin for "The Species of Plants") is a book by Carl Linnaeus, originally published in 1753, which lists every species of plant known at the time, classified into genus, genera. It is the first work to consistently apply binomial nomenclature, binomial names and was the starting point for the botanical nomenclature, naming of plants. Publication ' was published on 1 May 1753 by Laurentius Salvius in Stockholm, in two volumes. A second edition was published in 1762–1763, and a third edition in 1764, although this "scarcely differed" from the second. Further editions were published after Linnaeus' death in 1778, under the direction of Karl Ludwig Willdenow, the director of the Berlin-Dahlem Botanical Garden and Botanical Museum, Berlin Botanical Garden; the fifth edition was titled "fourth edition" and was published by Willdenow in four volumes, 1798 (1), 1800 (2), 1801 (31), 1803 (32), 1804 (33), 1805 (41), 1806 (42), rather than the dates printed on the volumes themselves. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioactive Isotope
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferred to one of its electrons to release it as a conversion electron; or used to create and emit a new particle (alpha particle or beta particle) from the nucleus. During those processes, the radionuclide is said to undergo radioactive decay. These emissions are considered ionizing radiation because they are energetic enough to liberate an electron from another atom. The radioactive decay can produce a stable nuclide or will sometimes produce a new unstable radionuclide which may undergo further decay. Radioactive decay is a random process at the level of single atoms: it is impossible to predict when one particular atom will decay. However, for a collection of atoms of a single nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy Metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals is a controversial and ambiguous term for metallic elements with relatively high density, densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context and it has been argued that the term "heavy metal" should be avoided. A heavy metal may be defined on the basis of density, atomic number or chemical behaviour. More specific definitions have been published, none of which have been widely accepted. The definitions surveyed in this article encompass up to 96 out of the 118 known chemical elements; only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm3 is sometimes quoted as a commonly used criterion and is used in the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is Scientific consensus on climate change, driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, Deforestation and climate change, deforestation, and some Greenhouse gas emissions from agriculture, agricultural and Environmental impact of concrete, industrial practices release greenhouse gases. These gases greenhouse effect, absorb some of the heat that the Earth Thermal radiation, radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, Carbon dioxide in Earth's atmosphere, has increased in concentratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
