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Soil Production Function
Soil production function refers to the rate of bedrock weathering into soil as a function of soil thickness. A general model suggested that the rate of physical weathering of bedrock (de/dt) can be represented as an exponential decline with soil thickness: de/dt = P_0 \exp where ''h'' is soil thickness ''P0'' m/yearis the potential (or maximum) weathering rate of bedrock and ''k'' −1is an empirical constant. The reduction of weathering rate with thickening of soil is related to the exponential decrease of temperature amplitude with increasing depth below the soil surface, and also the exponential decrease in average water penetration (for freely-drained soils). Parameters ''P0'' and ''k'' are related to the climate and type of parent materials. found the value of ''P0'' ranges from 0.08 to 2.0 mm/yr for sites in Northern California, and 0.05–0.14 mm/yr for sites in Southeastern Australia. Meanwhile values of ''k'' do not vary significantly, ranging from 2 to 4 m−1. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prod Fun
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Prod or PROD may refer to: *Cattle prod, a device used to goad livestock into moving *Public Request to Order Disposal, part of the Local Government, Planning and Land Act 1980 * Prod, a village in Hoghilag Commune, Sibiu County, Romania *Product integral, often shown using the symbol \prod * "Prod", a song by Mudvayne from '' L.D. 50'' *Prod, the bow or spring part of a crossbow *Prod., an abbreviation of production (other) *Prod, a derogatory abbreviation for a Protestant person in Northern Ireland *PROD, a method of deletion of articles on Wikipedia Volunteer editors of Wikipedia delete articles on the online encyclopedia on a regular basis, following processes that have been formulated by the site's community over time. The most common route is outright deletion of articles that are clearl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biorhexistasy
The theory of biorhexistasy describes climatic conditions necessary for periods of soil formation (pedogenesis) separated by periods of soil erosion. Proposed by pedologist Henry Erhart in 1951, the theory defines two climatic phases: biostasy and rhexistasy. Biostasy During biostasy, abundant and regular precipitation induces strong pedogenesis characterized by chemical alteration of parent material and intensified eluviation and illuviation of soil minerals within the surface soil and subsoil layers (the solum). These processes contribute to the formation of eluvial and argillic horizons and an increased concentration of iron oxides, aluminum oxides, and other sesquioxides in the subsoil. Climatic conditions favor a vegetative cover which protects the soil from physical erosion but abundant rainfall results in the loss of mineral ions and increased concentration of those minerals in receiving bodies of water. Abundant marine calcium results in limestone formation. Rhexista ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Surface Processes And Landforms
''Earth Surface Processes and Landforms'' is a peer-reviewed scientific journal published by John Wiley & Sons on behalf of the British Society for Geomorphology. It covers geomorphology and more in general all aspects of Earth sciences dealing with the Earth surface. The journal was established in 1976 as ''Earth Surface Processes'', obtaining its current name in 1981. The journal primarily publishes original research papers. It also publishes ''Earth Surface Exchanges'' which include commentaries on issues of particular geomorphological interest, discussions of published papers, shorter journal articles suitable for rapid publication, and commissioned reviews on key aspects of geomorphological science. Foci include the physical geography of rivers, valleys, glaciers, mountains, hills, slopes, coasts, deserts, and estuary environments, along with research into Holocene, Pleistocene, or Quaternary science. The editor-in-chief is Stuart Lane (University of Lausanne). Abstracting and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2019 ''Journal Citation Reports'' (with an ascribed impact factor of 42.778), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in autumn 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander Macmillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the journal; ''Nature'' redoubled its efforts in exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weathering
Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement), and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are divided into ''physical'' and ''chemical weathering''. Physical weathering involves the breakdown of rocks and soils through the mechanical effects of heat, water, ice, or other agents. Chemical weathering involves the chemical reaction of water, atmospheric gases, and biologically produced chemicals with rocks and soils. Water is the principal agent behind both physical and chemical weathering, though atmospheric oxygen and carbon dioxide and the activities of biological organisms are also important. Chemical weathering by biological action is also known as biological wea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Functions
Soil functions are general capabilities of soils that are important for various agricultural, environmental, nature protection, landscape architecture and urban applications. Soil can perform many functions and these include functions related to the natural ecosystems, agricultural productivity, environmental quality, source of raw material, and as base for buildings. Six key soil functions are: #Food and other biomass production #Environmental Interaction #Biological habitat and gene pool #Source of raw materials #Physical and cultural heritage #Platform for man-made structures Food and other biomass production Soil acts as an anchor for plant roots. It provides a hospitable place for a plant to live in while storing and supplying nutrients to plants. Soil also functions by maintaining the quantity and quality of air by allowing to escape and fresh to enter the root zone. Pore spaces within soil can also absorb water and hold it until plant roots need it. The soil also moderat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedogenesis
Soil formation, also known as pedogenesis, is the process of soil genesis as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizon, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors. Pedogenesis is studied as a branch of pedology, the study of soil in its natural environment. Other branches of pedology are the study of soil morphology, and soil classification. The study of pedogenesis is important to understanding soil distribution patterns in current ( soil geography) and past (paleopedology) geologic periods. Overview Soil develops through a series of changes. The starting point is weathering of freshly accumulated parent material. A variety of soil microbes (bacteria, ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parent Material
Parent material is the underlying geological material (generally bedrock or a superficial or drift deposit) in which soil horizons form. Soils typically inherit a great deal of structure and minerals from their parent material, and, as such, are often classified based upon their contents of consolidated or unconsolidated mineral material that has undergone some degree of physical or chemical weathering and the mode by which the materials were most recently transported. Consolidated Parent materials that are predominantly composed of consolidated rock are termed residual parent material. The consolidated rocks consist of igneous, sedimentary, and metamorphic rock, etc. Residual Soil developed in residual parent material is that which forms in consolidated geologic material. Unconsolidated Parent material is classified by its last means of transport. Material that was transported to a location by glacier, then deposited elsewhere by streams, is classified as stream-transported p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hillslope Evolution
Hillslope evolution is the changes in the erosion rates, erosion styles and form of slopes of hills and mountains over time. Conceptual models During most of the 20th century three models of hillslope evolution were widely diffused: slope decline, slope replacement and parallel slope retreat. Until the 1950s models of hillslope form evolution were central in geomorphology. The modern understanding is that the evolution of slopes is much more complex than the classical models of decline, replacement and retreat imply. Slope decline Slope decline was proposed by William Morris Davis in his cycle of erosion theory. It consists of a gradual decrease in slope angle as stream incision slows down. This is accompaigned as slopes becomes more gentle they accumulate with fine-grained regolith stemming from weathering. Slope replacement Slope replacement was first proposed by Walther Penck challenging Davis' ideas on slope development. Slope replacement describes an evolution of slopes tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grove Karl Gilbert
Grove Karl Gilbert (May 6, 1843 – May 1, 1918), known by the abbreviated name G. K. Gilbert in academic literature, was an American geologist. Biography Gilbert was born in Rochester, New York and graduated from the University of Rochester. During the American Civil War, he was twice listed for the draft, but his name was drawn neither time. In 1871, he joined George M. Wheeler's geographical survey as its first geologist. Rockies geologist He then joined the Powell Survey of the Rocky Mountain Region in 1874, becoming Powell's primary assistant, and stayed with the survey until 1879. During this time he published an important monograph, ''The Geology of the Henry Mountains'' (1877). After the creation of the U.S. Geological Survey in 1879, he was appointed to the position of Senior Geologist and worked for the USGS until his death (including a term as acting director). Gilbert published a study of the former ancient Lake Bonneville in 1890 (the lake existed during the P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bedrock
In geology, bedrock is solid Rock (geology), rock that lies under loose material (regolith) within the crust (geology), crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of bedrock is often called an outcrop. The various kinds of broken and weathered rock material, such as soil and subsoil, that may overlie the bedrock are known as regolith. Engineering geology The surface of the bedrock beneath the soil cover (regolith) is also known as ''rockhead'' in engineering geology, and its identification by digging, drilling or geophysics, geophysical methods is an important task in most civil engineering projects. Superficial deposition (geology), deposits can be very thick, such that the bedrock lies hundreds of meters below the surface. Weathering of bedrock Exposed bedrock experiences weathering, which may be physical or chemical, and which alters the structure of the rock to leave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landscape Evolution Model
A landscape evolution model is a physically-based numerical model that simulates changing terrain over the course of time. The change in, or evolution of, terrain, can be due to: glacial or fluvial erosion, sediment transport and deposition, regolith production, the slow movement of material on hillslopes, more intermittent events such as rockfalls, debris flows, landslides, and other surface processes. These changes occur in response to the land surface being uplifted above sea-level (or other base-level) by surface uplift, and also respond to subsidence. A typical landscape evolution model takes many of these factors into account. Landscape evolution models are used primarily in the field of geomorphology. As they improve, they are beginning to be consulted by land managers to aid in decision making, most recently in the area of degraded landscapes. The earliest landscape evolution models were developed in the 1970s. In those models, flow of water across a mesh was simulated, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
