what is the meaning of deep percolation rate (irrigation)?
478983
Fast draining soils (say greater than 3 feet/day) are poor for irrigation since the water doesn't stay in the upper layers very long, it penetrates (or percolates) into the deeper layers before the plants have a chance to absorb it.
660157
Soil is the material on the surface of a lithosphere subject to weathering, and especially the earthy portion of that material.\n\nSoil components\n\n    * Composition -- A typical surface soil is half solids and half voids or porosity. Water and air are thus integral components of soils. Water occupies the void space between soil particles and is held by surface tension on particle surfaces. Air occupies the remaining void space. Both water and air components of soils are important to plant growth and other life in the soil profile of a particular ecosystem\n    * Soil texture -- refers to soil grain size, sand = 2 to 0.02 or 0.05 mm; silt = 0.02 or 0.05 to 0.002 mm; clay = <0.002 mm. Soil texture influences available water capacity and movement, fertility, and workability or "tilth". "Loam" is a name for one of various mixtures of these three particle sizes. The ratio of these particles determines soil texture classification.\n    * Soil structure -- the arrangement of soil particles into aggregates, which may have various shapes, sizes and degrees of development or expression. Soil structure influences aeration, water movement, erosion resistance, and root penetration.\n    * Slope -- the inclination of the ground surface. Slope influences runoff of rainfall, soil erosion, stability, and machinery operation.\n    * Soil color -- Soil color often indicates soil moisture status and is used for determining hydric soils. Often described using general terms, such as dark brown, yellowish brown, etc., soil colors are also described more technically by using Munsell soil color charts, which separate color into components of hue (relation to red, yellow and blue), value (lightness or darkness) and chroma (paleness or strength).\n    * Soil chemistry -- A complex subject within soil science; the most important subjects are:\n\n        Soil pH -- The acidity or alkalinity of soils, which affects plant growth and soil fertility.\n        Cation Exchange Capacity -- The soil's ability to retain and exchange positively charged ions, which include major plant nutrients.\n        Reduction and oxidation (Redox) reactions are also important.\n\n    * The soil profile -- A vertical cut that exposes soil layering or soil horizons. Horizons are formed by combined biological, chemical and physical alterations. A, B, and C symbols are used to describe the topsoil, subsoil and substratum, respectively.\n    * Permeability -- The ability of a soil to transmit water or air. Faster or greater permeability often occurs in sandy or gravelly soils due to large pore spaces. Slower permeability typically occurs in finer textured clay soils, or compacted soils with little structure.\n    * Drainage -- The rate in which water is removed from a soil. Drainage influences most uses of soils, whether for agriculture, silviculture or urban. Classes of soil drainage are those found in soil survey reports, such as well drained, moderately well drained, somewhat poorly drained, poorly drained, and very poorly drained. Soil color patterns (such as mottle patterns or redoximorphic features) often indicate soil drainage class. The most productive agricultural soils are typically well drained or moderately well drained, as are the soils easiest to develop for urban use. By contrast, hydric soils are poorly or very poorly drained. A soil's natural drainage rate can be significantly increased by subsurface "tile" drainage.\n    * Soil biology -- Soils serve as habitats for soil organisms varying in size from microorganisms to small animals. The character of soils is intricately tied to bioturbation and the biochemical functions performed by soil organisms. The soil is home to a large proportion of the world's genetic diversity, which changes by soil type: desert soils (like aridisols) generally have more complex soil biotic communities and genetic diversity than tropical soils (like oxisols).\n    * Soil smell -- earthy odor
270375
It depends on a lot of things. Among them, you should consider the amount of erosion, presence of water, wind, all those weathering factors that could impact the rate at which dirt (I'm guessing) accumulates.
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Porosity:\n\nThe percentage of the total volume of rock or soil that consists of open spaces. (The space between particles is called pore space.) It describes how densely the material is packed .\n\nPermeability:\n\nA measure of a material's ability to transmit liquids.\n\nExample: Upon discovery of a Leaking Underground Storage Tank (LUST) the soil beneath it was tested. The greater the permeability, the more rapidly the liquid could reach an underground stream or aquifer.
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A permanent irrigation conduit constructed to convey water from the source of supply to one or more farms.
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It appears to be in relation to energy production.  I have referenced a hyperlink to a PDF file that refers to this term with in its context...the file does have some English translation.
350186
To provide water to hillside communities, the distribution system has to be stratified into multiple zones with each zone serving a specific elevation area. This stratified design is known as a "cascade system."
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they improve water holding capacity of sandy soil.\nthey also increase infiltration rates of water through clay soils.\nthey absorb, store and release soluble fertilizer and nutrients.\nso, they are used in farming and gardening (agricultural uses)\nan example is CuSO4.5H2O (pentahydrate copper sulfate)!
124552
Soil absorbs moisture. It has small openings and the water gets in the small holes. The cohesion and adhesion of the water constitute a force that keeps the water in the soil, to a certain extent.
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In physics, thermal conductivity, k, is the intensive property of a material that indicates its ability to conduct heat.\n\nIt is defined as the quantity of heat, Q, transmitted in time t through a thickness L, in a direction normal to a surface of area A, due to a temperature difference ΔT, under steady state conditions and when the heat transfer is dependent only on the temperature gradient.\n\nthermal conductivity = heat flow rate × distance / (area × temperature difference)\n\n\nElectrical conductance is the reciprocal of electrical resistance. It is a measure of how easily electricity flows along a certain path through an object. The SI derived unit of conductance is the siemens (symbol S, equal to 1/Ω; alias the "mho"). Oliver Heaviside coined the term in September 1885.
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Don't irrigate.  What farmers are seeing in California were irrigation is done intensively is an increase in the salinity of the soil.  Surface irrigation exposes the water to rapid evaporation, but the dissolved constituents in the water remain behind.  Over time this increases the salinity of the soil.\n\nSo if you must irrigate, you probably want to do subsurface irrigation.
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If it is just about vertical infiltration, you can use Green-Ampht equation or simply Darcy's law if the soil is saturatted.\nThese require, soil properties such as porocity, field capacity, hydraulic conductivity and rainfall intensity.\n\nFor more realistic and regional studies, you can use \nWater balance method, Penman-montith method, \nThe above require all sorts of meteorologic information including solar radiation. The water balance method is much simpler but you need a long-time record. P=M method is very complex so you'll be better off to use HELP 3 model that kind of automates the process. This DOS based model can be downloaded at USGS website.
21118
You're probably talking about the thermal conductivity of materials, which is defined as the ability of bodies to conduct heat through them. Water is not such a great conductor of heat, which means it will take long for it to conduct heat - either to heat itself up, or give out heat.
34823
Just like oxygen, hydrogen, nitrogen; NaCl is found everywhere on earth.\n\nBeing water soluable, it has been getting moved around ALOT.  When water evaporates completely, it will leave the salt behind.  The dead sea is a perect example.  Left long enough the dead sea will form a solid mass of dry salt.  Salt deposits like these can be fould all over buried the world.\n\nOne of the balancing acts with irrigation is that salt will build up in soils to point that nothing will grow.
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The process in which a solid (soil) takes on the characteristics of a liquid as a result of an increase in pore pressure and a reduction in stress. In other words, solid ground turns to jelly.\nwww.msnucleus.org/membership/html/jh/earth/dictionary/platedict.html\n\nChanging a solid into a liquid.
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if it's from an area of high concentration to low concentration, it's osmosis.\n\nif it's from an area of low concentration to high concentration, it's active transport.
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What you are seing are crops irrigated by center pivot irrigators.\n\nCenter pivot irrigation is a form of overhead irrigation consisting of several segments of pipe (usually galvanized steel or aluminum) joined together and supported by trusses, mounted on wheeled towers with sprinklers positioned along its length. The system moves in a circular pattern and is fed with water from the pivot point at the center of the arc. These systems are common in parts of the United States where terrain is flat.