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Western Gulf Coastal Grasslands
The Western Gulf coastal grasslands () are a tropical and subtropical grasslands, savannas, and shrublands, subtropical grassland ecoregion of the southern United States and northeastern Mexico. It is known in Louisiana as the "Cajun Prairie", Texas as "Coastal Prairie," and as the Tamaulipan pastizal () in Mexico. Setting The ecoregion covers an area of , extending along the shore of the Gulf of Mexico from southeastern Louisiana (west of the Mississippi Delta) through Texas and into the Mexican state of Tamaulipas as far as the Laguna Madre (Mexico), Laguna Madre. Specific areas include a number of barrier islands, and the ''Resaca (channel), resacas'' or natural levees of the Laguna Madre. The coast is vulnerable to tropical storms that can seriously damage habitats. This ecosystem, in part, has Edaphology, edaphic origins: the soils of this ecoregion are largely dominated by vertisol clays, the mechanical properties of which make it difficult for many tree species to grow an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attwater's Prairie Chicken
Attwater's prairie-chicken (''Tympanuchus cupido attwateri'') is a highly endangered subspecies of the greater prairie-chicken that is native to Western Gulf coastal grasslands, coastal Texas and formerly Louisiana in the United States. Description Attwater's prairie-chicken measures 17–18 in (43–45.5 cm) and weighs roughly 1.5 to 2.0 lb (0.7 to 0.9 kg). It has a 28-in (70-cm) wingspan. These grouse have strong vertical bars of dark brown and buff-white pattern over the mantle, flanks, and underparts. The species exhibits sexual dimorphism, with the males having elongated feathers, called pinnae, erected to form what looks like ear-like structures. The male also has a bright orange or golden air sac on either side of his neck, which he inflates during Courtship display, mating displays. They have a lifespan of 2–5 years. Habitat and range ''T. c. attwateri'' is endemic to the Western Gulf coastal grasslands. Its range historically stretched west from Bayou Teche i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecoregion
An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species. The biodiversity of flora, fauna and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. In theory, biodiversity or conservation ecoregions are relatively large areas of land or water where the probability of encountering different species and communities at any given point remains relatively constant, within an acceptable range of variation (largely undefined at this point). Ecoregions are also known as "ecozones" ("ecological zones"), although that term may also refer to biogeographic realms. Three caveats are appropriate for all bio-geographic mapping approaches. Firstly, no single bio-geographic fram ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floodplain
A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high Discharge (hydrology), discharge.Goudie, A. S., 2004, ''Encyclopedia of Geomorphology'', vol. 1. Routledge, New York. The soils usually consist of clays, silts, sands, and gravels deposited during floods. Because of regular flooding, floodplains frequently have high soil fertility since nutrients are deposited with the flood waters. This can encourage farming; some important agricultural regions, such as the Nile and Mississippi Basin, Mississippi Drainage basin, river basins, heavily exploit floodplains. Agricultural and urban regions have developed near or on floodplains to take advantage of the rich soil and freshwater. However, the Flood risk, risk of inundation has led to increasing efforts to Flood control, control flooding. Formation Most floodplai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silt
Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension (chemistry), suspension with water. Silt usually has a floury feel when dry, and lacks Plasticity (physics), plasticity when wet. Silt can also be felt by the tongue as granular when placed on the front teeth (even when mixed with clay particles). Silt is a common material, making up 45% of average modern mud. It is found in many river deltas and as wind-deposited accumulations, particularly in central Asia, north China, and North America. It is produced in both very hot climates (through such processes as collisions of quartz grains in dust storms) and very cold climates (through such processes as glacial grinding of quartz grains.) Loess is soil rich in silt which makes up some of the most fertile agricultural land on Earth. However, silt is very vulnerable to erosion, and it has poo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz. Calcium carbonate is the second most common type of sand. One such example of this is aragonite, which has been created over the past 500million years by various forms of life, such as coral and shellfish. It is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years, as in the Caribbean. Somewhat more rarely, sand may be composed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clays develop plasticity (physics), plasticity when wet but can be hardened through Pottery#Firing, firing. Clay is the longest-known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been radiocarbon dating, dated to around 14,000 BCE, and Clay tablet, clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtration, filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, often baked into brick, as an essenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertisol
A vertisol is a Soil Order in the USDA soil taxonomy and a Reference Soil Group in the World Reference Base for Soil Resources (WRB). It is also defined in many other soil classification systems. In the Australian Soil Classification it is called vertosol. The natural vegetation of vertisols is grassland, savanna, or grassy woodland. The heavy texture and unstable behaviour of the soil makes it difficult for many tree species to grow, and forest is uncommon. Composition Vertisols have a high content of expansive clay minerals (many of them belonging to the montmorillonites) that form deep cracks in drier seasons or years. In a phenomenon known as argillipedoturbation, alternate shrinking and swelling causes ''self-ploughing'', where the soil material consistently mixes itself, causing some vertisols to have an extremely deep A horizon and no B horizon. (A soil with no B horizon is called an ''A/C soil''). This heaving of the underlying material to the surface often create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edaphology
Edaphology (from Greek , ''edaphos'' 'ground' + , ''-logia'') is concerned with the influence of soils on living beings, particularly plants. It is one of two main divisions of soil science, the other being pedology. Edaphology includes the study of how soil influences humankind's use of land for plant growth as well as people's overall use of the land. General subfields within edaphology are agricultural soil science (known by the term agrology in some regions) and environmental soil science. Pedology deals with pedogenesis, soil morphology, and soil classification. History The history of edaphology is not simple, as the two main alternative terms for soil science—pedology and edaphology—were initially poorly distinguished. Friedrich Albert Fallou originally conceived pedology in the 19th century as a fundamental science separate from the applied science of agrology, a predecessor term for edaphology, a distinction retained in the current understanding of edaphology. D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levee
A levee ( or ), dike (American English), dyke (British English; see American and British English spelling differences#Miscellaneous spelling differences, spelling differences), embankment, floodbank, or stop bank is an elevated ridge, natural or artificial, alongside the river banks, banks of a river, often intended to flood control, protect against flooding of the area adjoining the river. It is usually soil, earthen and often runs parallel (geometry), parallel to the course of a river in its floodplain or along low-lying coastlines. Naturally occurring levees form on river floodplains following flooding. Sediment and alluvium are deposition (geology), deposited on the banks and settle, forming a ridge that increases the river channel's capacity. Alternatively, levees can be artificially constructed from fill dirt, fill, designed to regulate water levels. In some circumstances, artificial levees can be environmental degradation, environmentally damaging. Ancient civilization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resaca (channel)
Resaca is the name given to a type of oxbow lake in the southern half of Cameron County, Texas. The resacas constitute former channels of the Rio Grande and are naturally cut off from the river, having no inlet or outlet. History The Rio Grande's water moves from Colorado to the Gulf of Mexico. Every year during spring, melted snow would flow into the Rio Grande, bringing seasonal flood waters to the most southern tip of Texas. Given the overflow of the river's main and distributary channel banks, the Rio Grande would carve new river channels, known as ''resacas.'' When the seasonal flooding ended and the river retreated, the newly formed oxbow lakes remained, creating ''resacas'' all throughout the Rio Grande Valley. Etymology There are two explanations for the origin of the word ''resaca.'' The first explanation holds that it is a contraction of the Spanish phrase ''rio seco'' (dry river). The second explanation is that the word stems from the Spanish word ''resacar'' (to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barrier Island
Barrier islands are a Coast#Landforms, coastal landform, a type of dune, dune system and sand island, where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen. They are subject to change during storms and other action, but absorb energy and protect the coastlines and create areas of protected waters where wetlands may flourish. A barrier chain may extend for hundreds of kilometers, with islands periodically separated by tidal inlets. The longest barrier island in the world is Padre Island of Texas, United States, at long. Sometimes an important inlet may close permanently, transforming an island into a peninsula, thus creating a barrier peninsula, often including a beach, barrier beach. Though many are long and narrow, the length and width of barriers and overall morphology of barrier coasts are related to parameters including tidal range, wave ener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laguna Madre (Mexico)
Laguna Madre is a coastal lagoon in Northeastern Mexico. It extends along the coast of Tamaulipas for over 200 km, from the Río Bravo Delta on the north to the mouth of the Soto la Marina River near La Pesca in the south. Laguna Madre is separated from the Gulf of Mexico on the east by a number of barrier islands, including Barra Los Americanos, Barra Jesús María, and Barra Soto la Marina, and is bounded on the west by the Tamaulipan mainland. It is located in the municipalities of Matamoros, San Fernando, and Soto la Marina. There is another Laguna Madre in the United States, which extends north from the Río Bravo Delta to Corpus Christi Bay and the city of Corpus Christi in southern Texas. Together the two lagoons and delta form a single ecological unit approximately in total.Tunnell, Jr. John W. and Frank W. Judd. editors. (2002). ''The Laguna Madre of Texas and Tamaulipas''. Texas A&M University Press, College Station, Texas. xxi, 346 pp. Characteristics The L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
