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Alkali Sink
An alkali sink is a salty basin land form. In these depressions, which are found only in the San Joaquin Valley, California, rainwater drains to the basin and collects in areas where it cannot penetrate the soil due to a hard layer of clay or caliche, producing a pond or lake. When the water evaporates, it leaves behind increasing amounts of salt and minerals in the soil, creating a high pH level in the water and soil. The term may also refer to a North American desert vegetation type (biome) characteristic of that landform.Pam MacKay, Mojave Desert Wildflowers, 2nd Ed., p. 15-16 Plants that tolerate the extreme salt concentrations are known as halophyte A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity, coming into contact with saline water through its roots or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs, and seashores. ...s. It is generally below the saltbrush scrub vegetation type, which is ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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] [Amazon] |
Caliche
Caliche () is a soil accumulation of soluble calcium carbonate at depth, where it precipitates and binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions, including in central and western Australia, in the Kalahari Desert, in the High Plains (United States), High Plains of the western United States, in the Sonoran Desert, Chihuahuan Desert and Mojave Desert of North America, and in eastern Saudi Arabia at Al-Ahsa Oasis, Al-Hasa. Caliche is also known as calcrete or kankar (in India). It belongs to the duricrusts. The term is borrowed from Spanish and is originally from the Latin word , meaning Lime (mineral), lime. Caliche is generally light-colored but can range from white to light pink to reddish-brown, depending on the minerals present. Caliche is a mark of older landscapes. It generally occurs on or very near the surface. Where caliche layers originate at some depth from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Vegetation Type
Vegetation classification is the process of classifying and mapping the vegetation over an area of the Earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource and environmental management. Many different methods of vegetation classification have been used. In general, there has been a shift from structural classification used by forestry for the mapping of timber resources, to floristic community mapping for biodiversity management. Whereas older forestry-based schemes considered factors such as height, species and density of the woody canopy, floristic community mapping shifts the emphasis onto ecological factors such as climate, soil type and floristic associations. Classification mapping is usually now done using geographic information systems (GIS) software. Classification schemes Following, some important classification schemes. Köppen (1884) Although this scheme is in fact of a climate classification, it has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Biome
A biome () is a distinct geographical region with specific climate, vegetation, and animal life. It consists of a biological community that has formed in response to its physical environment and regional climate. In 1935, Tansley added the climatic and soil aspects to the idea, calling it ''ecosystem''. The International Biological Program (1964–74) projects popularized the concept of biome. However, in some contexts, the term ''biome'' is used in a different manner. In German literature, particularly in the Walter terminology, the term is used similarly as '' biotope'' (a concrete geographical unit), while the biome definition used in this article is used as an international, non-regional, terminology—irrespectively of the continent in which an area is present, it takes the same biome name—and corresponds to his "zonobiome", "orobiome" and "pedobiome" (biomes determined by climate zone, altitude or soil). In the Brazilian literature, the term ''biome'' is sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Halophyte
A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity, coming into contact with saline water through its roots or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs, and seashores. The word derives from Ancient Greek ἅλας (halas) 'salt' and φυτόν (phyton) 'plant'. Halophytes have different anatomy, physiology and biochemistry than glycophytes.Physiology of halophytes, T. J. FLOWERS, Plant and Soil 89, 41–56 (1985) An example of a halophyte is the salt marsh grass '' Spartina alterniflora'' (smooth cordgrass). Relatively few plant species are halophytes—perhaps only 2% of all plant species. Information about many of the earth's halophytes can be found in thhalophytedatabase. The large majority of plant species are glycophytes, which are not salt-tolerant and are damaged fairly easily by high salinity. Classification Halophytes can be classified in many ways. According to Stocker (1933), it is mainly o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Saltbrush Scrub
''Atriplex'' () is a plant genus of about 250 species, known by the common names of saltbush and orache (; also spelled orach). It belongs to the subfamily Chenopodioideae of the family Amaranthaceae ''s.l.''. The genus is quite variable and widely distributed. It includes many desert and seashore plants and halophytes, as well as plants of moist environments. The generic name originated in Latin and was applied by Pliny the Elder to the edible oraches. The name saltbush derives from the fact that the plants retain salt in their leaves; they are able to grow in areas affected by soil salination. Description Species of plants in genus ''Atriplex'' are annual or perennial herbs, subshrubs, or shrubs. The plants are often covered with bladderlike hairs, that later collapse and form a silvery, scurfy or mealy surface, rarely with elongate trichomes. The leaves are arranged alternately along the branches, rarely in opposite pairs, either sessile or on a petiole, and are sometime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Fluvial Landforms
Landforms related to rivers and other watercourses include: * * * * * (watershed) * * *Fluvial landforms of streams A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a strea ... * * (Gorge) * * * * * * * * * * * * * * * * * * * *{{annotated link, Yazoo stream See also * Glossary_of_landforms ** Glossary_of_landforms#Fluvial_landforms F F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Salt Flats
Salt flats, Salt flat, Salt Flats, or Salt Flat may refer to: Geology *Salt pan (geology), a flat expanse of ground covered with salt and other minerals *Dry lake, an ephemeral lakebed that consists of fine-grained sediments infused with alkali salts *Salt marsh, a coastal ecosystem between land and open saltwater that is regularly flooded, sometimes informally described as a salt flat Places *Bonneville Salt Flats in Tooele County, Utah, United States * Salt Flat, Texas, unincorporated community in Hudspeth County, Texas, United States *Salar_de_Uyuni Salar de Uyuni (or "Salar de Tunupa") is the world's largest salt flat, or playa, at in area. It is in the Daniel Campos Province in Potosí in southwest Bolivia, near the crest of the Andes at an elevation of above sea level. The Salar wa ..., Bolivia See also * Sand Flat (other) {{disambiguation, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Salt Flats Of The United States
In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as rock salt or halite. Salt is essential for life in general (being the source of the essential dietary minerals sodium and chlorine), and saltiness is one of the basic human tastes. Salt is one of the oldest and most ubiquitous food seasonings, and is known to uniformly improve the taste perception of food. Salting, brining, and pickling are ancient and important methods of food preservation. Some of the earliest evidence of salt processing dates to around 6000 BC, when people living in the area of present-day Romania boiled spring water to extract salts; a salt works in China dates to approximately the same period. Salt was prized by the ancient Hebrews, Greeks, Romans, Byzantines, Hittites, Egyptians, and Indians. Salt became an impo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Deserts And Xeric Shrublands
Deserts and xeric shrublands are a biome defined by the World Wide Fund for Nature. Deserts and xeric (Ancient Greek 'dry') shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area. Ecoregions in this habitat type vary greatly in the amount of annual rainfall they receive, usually less than annually except in the margins. Generally evaporation exceeds rainfall in these ecoregions. Temperature variability is also diverse in these lands. Many deserts, such as the Sahara Desert, Sahara, are hot year-round, but others, such as East Asia's Gobi Desert, become quite cold during the winter. Temperature extremes are a characteristic of most deserts. High daytime temperatures give way to cold nights because there is no insulation provided by humidity and cloud cover. The diversity of climatic conditions, though quite harsh, supports a rich array of habitats. Many of these habitats are ephemeral in nature, reflecting the paucity and seasonality of avail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Deserts And Xeric Shrublands In The United States
A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the land surface of the Earth is arid or Semi-arid climate, semi-arid. This includes much of the Polar regions of Earth, polar regions, where little precipitation occurs, and which are sometimes called polar deserts or "cold deserts". Deserts can be classified by the amount of precipitation that falls, by the temperature that prevails, by the causes of desertification or by their geographical location. Deserts are formed by weathering processes as large variations in temperature between day and night strain the Rock (geology), rocks, which consequently break in pieces. Although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Rain falling on hot rocks can cause them to shatter, and the resulting frag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
North American Desert Flora
North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north'' is related to the Old High German ''nord'', both descending from the Proto-Indo-European unit *''ner-'', meaning "left; below" as north is to left when facing the rising sun. Similarly, the other cardinal directions are also related to the sun's position. The Latin word ''borealis'' comes from the Greek ''boreas'' "north wind, north" which, according to Ovid, was personified as the wind-god Boreas, the father of Calais and Zetes. ''Septentrionalis'' is from ''septentriones'', "the seven plow oxen", a name of ''Ursa Major''. The Greek ἀρκτικός (''arktikós'') is named for the same constellation, and is the source of the English word ''Arctic''. Other languages have other derivations. For example, in Lezgian, ''kefer'' can mean bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
