|
Sporobolus Foliosus
''Sporobolus foliosus'' is a species of grass known by the common name California cordgrass. It was reclassified from ''Spartina foliosa'' after a taxonomic revision in 2014. It is native to the salt marshes and mudflats of coastal California and Baja California, especially San Francisco Bay. It is a perennial grass growing from short rhizomes. It produces single stems or clumps of thick, fleshy stems that grow up to 1.5 meters tall. They are green or purple-tinged. The long, narrow leaves are flat or rolled inward. The inflorescence is a narrow, dense, spike-like stick of branches appressed together, the unit reaching up to 25 centimeters long. The lower spikelets are sometimes enclosed in the basal sheaths of upper leaves. This native plant is seriously threatened by the invasion of its North American Atlantic coast relative smooth cordgrass (''Sporobolus alterniflorus''), which is not native to the Pacific coast. ''S. alterniflorus'' was introduced to San Francisco Bay in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trin
Trin is a municipalities of Switzerland, municipality in the Imboden Region in the Switzerland, Swiss Cantons of Switzerland, canton of Graubünden. Crestasee is located in Trin. History Trin is first mentioned in the 12th Century as ''Turunnio''. Geography Trin is perched on the mountain-side above the Rhine valley on the road between Domat/Ems and Flims. The village of Mulin (also in the municipality) is at the foot of the slope on the edge of the valley. Trin has an area, , of . Of this area, 33.2% is used for agricultural purposes, while 24.3% is forested. Of the rest of the land, 1.7% is settled (buildings or roads) and the remainder (40.8%) is non-productive (rivers, glaciers or mountains). Before 2017, the municipality was located in the Trins sub-district of the Imboden district, after 2017 it was part of the Imboden Region. It consists of the villages of Trin, Digg and Mulin. Until 1943 Trin was known as Trins. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridisation, which include genetic and morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo. Some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Grasses Of California
Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (other) In arts and entertainment * Native (band), a French R&B band * Native (comics), a character in the X-Men comics universe * ''Native'' (album), a 2013 album by OneRepublic * ''Native'' (2016 film), a British science fiction film * ''The Native'', a Nigerian music magazine In science * Native (computing), software or data formats supported by a certain system * Native language, the language(s) a person has learned from birth * Native metal, any metal that is found in its metallic form, either pure or as an alloy, in nature * Native species, a species whose presence in a region is the result of only natural processes Other uses * Northeast Arizona Technological Institute of Vocational Education (NATIVE), a technology school district in the Arizona portion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporobolus
''Sporobolus'' is a nearly cosmopolitan genus of plants in the grass family. The name ''Sporobolus'' means "seed-thrower", and is derived from Ancient Greek word (), meaning "seed", and the root of () "to throw", referring to the dispersion of seeds. Members of the genus are usually called dropseeds or sacaton grasses. They are typical prairie and savanna plants, occurring in other types of open habitat in warmer climates. At least one species ('' S. caespitosus'' from Saint Helena) is threatened with extinction, and another ('' S. durus'' from Ascension Island) is extinct. Uses While some dropseeds, such as prairie dropseed (''Sporobolus heterolepis''), make nice gardening plants, they are generally considered to make inferior pastures, but seeds of at least some species are edible and nutritious; they were used as food, for example, by the Chiricahua Apaches. Other species are reported to be used as famine foods, such as ''Sporobolus indicus'' in parts of the Oromia Region of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tidal Marsh
A tidal marsh (also known as a type of "tidal wetland") is a marsh found along rivers, coasts and estuaries which floods and drains by the tidal movement of the adjacent estuary, sea or ocean. Tidal marshes are commonly zoned into lower marshes (also called intertidal marshes) and upper or high marshes, based on their elevation above sea level. A middle marsh zone also exists for tidal freshwater marshes. Tidal marshes may be further classified into back-barrier marshes, estuarine brackish marshes and tidal freshwater marshes, depending on the influence of sea level. Coastal Coastal tidal marshes are found within coastal watersheds and encompass a variety of types including fresh and salt marshes, bottomland hardwood swamps, mangrove swamps, and palustrine wetlands. Island and barrier island Tidal Marshes also form between a main shoreline and barrier islands. These elongated shifting landforms evolve parallel and in close proximity to the shoreline of a tidal marsh. Many becom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid Vigor
Heterosis, hybrid vigor, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of its parents. These effects can be due to Mendelian or non-Mendelian inheritance. Definitions In proposing the term heterosis to replace the older term heterozygosis, G.H. Shull aimed to avoid limiting the term to the effects that can be explained by heterozygosity in Mendelian inheritance. Heterosis is often discussed as the opposite of inbreeding depression, although differences in these two concepts can be seen in evolutionary considerations such as the role of genetic variation or the effects of genetic drift in small populations on these concepts. Inbreeding depression occurs when related parents have children with traits that negatively influence their fitness largely due to homozygosity. In such instances, outcrossing should ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fitness (biology)
Fitness (often denoted w or ω in population genetics models) is the quantitative representation of individual reproductive success. It is also equal to the average contribution to the gene pool of the next generation, made by the same individuals of the specified genotype or phenotype. Fitness can be defined either with respect to a genotype or to a phenotype in a given environment or time. The fitness of a genotype is manifested through its phenotype, which is also affected by the developmental environment. The fitness of a given phenotype can also be different in different selective environments. With asexual reproduction, it is sufficient to assign fitnesses to genotypes. With sexual reproduction, recombination scrambles alleles into different genotypes every generation; in this case, fitness values can be assigned to alleles by averaging over possible genetic backgrounds. Natural selection tends to make alleles with higher fitness more common over time, resulting in Darwin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Pollution
Genetic pollution is a controversial term for uncontrolled gene flow into wild populations. It is defined as "the dispersal of contaminated altered genes from genetically engineered organisms to natural organisms, esp. by cross-pollination", but has come to be used in some broader ways. It is related to the population genetics concept of gene flow, and genetic rescue, which is genetic material intentionally introduced to increase the fitness of a population. It is called genetic pollution when it negatively impacts the fitness of a population, such as through outbreeding depression and the introduction of unwanted phenotypes which can lead to extinction. Conservation biologists and conservationists have used the term to describe gene flow from domestic, feral, and non-native species into wild indigenous species, which they consider undesirable. They promote awareness of the effects of introduced invasive species that may "''hybridize with native species, causing genetic polluti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Local Extinction
Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a change in the ecology of an area. In recent times, local extinction has sometimes been followed by a replacement of the species taken from other locations; wolf reintroduction is an example of this. The term "local extinction" is highly vernacular. The more proper biological term is ''extirpation''. Discussion Glaciation can lead to local extinction. This was the case during the Pleistocene glaciation event in North America. During this period, most of the native North American species of earthworm were killed in places covered by glaciation. This left them open for colonization by European earthworms brought over in soil from Europe. Species naturally become extirpated from islands over time. The number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introduced Species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are ''new'' biota to their environment in terms of established biological network (e.g. food web) relationships. Neobiota can further be divided into neozoa (also: neozoons, sing. neozoon, i.e. animals) and neophyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poaceae
Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns and pasture. The latter are commonly referred to collectively as grass. With around 780 genera and around 12,000 species, the Poaceae is the fifth-largest plant family, following the Asteraceae, Orchidaceae, Fabaceae and Rubiaceae. The Poaceae are the most economically important plant family, providing staple foods from domesticated cereal crops such as maize, wheat, rice, barley, and millet as well as feed for meat-producing animals. They provide, through direct human consumption, just over one-half (51%) of all dietary energy; rice provides 20%, wheat supplies 20%, maize (corn) 5.5%, and other grains 6%. Some members of the Poaceae are used as building materials (bamboo, thatch, and straw); others can provide a source of biofuel, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
