L horizon Refer to soil horizon and Appendix II.
labile Readily transformed by microorganisms or readily available to plants.
labile pool The sum of an element in the soil solution and the amount of that element readily solubilized or exchanged when the soil is equilibrated with a salt solution.
labradorite A plagioclase feldspar containing 30 to 50% albite and 50 to 70% anorthite.
lacustrine deposit Clastic sediments and chemical precipitates deposited in lakes.
lacustrine soil Soil formed on or from lacustrine deposits.
lagoon [coast] A shallow stretch of salt or brackish water, partly or completely separated from a sea or lake by an offshore reef, barrier island, sandbank or spit ( Jackson, 1997).
lagoon bottom The nearly level or slightly undulating central portion of a submerged, low-energy, depositional estuarine basin (McGinn, 1982) characterized by relatively deep water (1.0 to >2.5 m). Compare bay bottom (Subaqueous Soils Subcommittee, 2005).
lagoon channel A subaqueous, sinuous area within a lagoon that likely represents a relict channel (paleochannel, Wells et al., 1994) that is maintained by strong currents during tidal cycles (Short, 1975; Subaqueous Soils Subcommittee, 2005).
lagoonal deposit Sand, silt or clay-sized sediments transported and deposited by wind, currents, and storm washover in the relatively low-energy, brackish to saline, shallow waters of a lagoon. Compare estuarine deposit, fluviomarine deposit, marine deposit (Subaqueous Soils Subcommittee, 2005).
lagtime Refer to irrigation, lagtime.
lahar The landform and sediments (lahar deposit) emplaced by and associated with a mudflow on or near a volcano that is composed mainly of volcaniclastic debris. Sediment composition includes pyroclastic material, primary lava flow blocks and fragments, and nonvolcanic material. Thick lahar deposits may have crude (poorly sorted) upward-fining strata. A lahar is initially an unconsolidated material, but through cementation and compression can become bedrock ( Jackson, 1997, Schoeneberger and Wysocki, personal communication, 2013). Compare mudflow, andesitic lahar, lahar deposit.
lahar deposit The unconsolidated sediments emplaced by a lahar. The sediment composition includes pyroclastic material, primary lava-flow blocks and fragments, and nonvolcanic material (Schoeneberger and Wysocki, personal communication, 2013).
lake [water] An inland body of permanently standing water fresh or saline, occupying a depression on the Earth’s surface, generally of appreciable size (larger than a pond) and too deep to permit vegetation (excluding subaqueous vegetation) to take root completely across the expanse of water ( Jackson, 1997).
lake plain A nearly level surface marking the floor of an extinct lake filled by well-sorted, generally fine-textured, stratified deposits, commonly containing varves ( Jackson, 1997).
lake terrace A narrow shelf, partly cut and partly built, produced along a lake shore in front of a scarp line of low cliffs and later exposed when the water level falls ( Jackson, 1997).
lakebed The bottom of a lake; a lake basin ( Jackson, 1997).
lakeshore The narrow strip of land in contact with or bordering a lake; especially the beach of a lake ( Jackson, 1997).
lamella [soil] A thin (<7.5 cm thick), discontinuous or continuous, generally horizontal layer of fine material (especially clay and iron oxides) that has been pedogenically concentrated (illuviated) within a coarser (e.g., sandy), eluviated layer (several centimeters to several decimeters thick; Schoeneberger and Wysocki, personal communication, 2013; Soil Survey Staff, 1975). Compare lamina.
lamina (noun) The thinnest recognizable layer (commonly < 1 cm thick) of original deposition in a sediment or sedimentary rock, differing from other layers in color, composition, or particle size. Several laminae constitute a bed ( Jackson, 1997). Compare lamella.
laminar flow Movement of water molecules at differing velocities but in parallel and sliding over one another without mixing.
lamination (not recommended) Use lamina.
land (a) The entire complex of surface and near surface attributes of the solid portions of the surface of the earth, which are significant to human activities; water bodies occurring within land masses are included in some land classification systems. (b) (economics) One of the major factors of production that is supplied by nature and includes all natural resources in their original state, such as mineral deposits, wildlife, timber, fish, water, coal, and the fertility of the soil.
land capability The suitability of land for use without permanent damage. Land capability, as ordinarily used in the United States, is an expression of the effect of physical land conditions, including climate, on the total suitability for use, without damage, for crops that require regular tillage, for grazing, for woodland, and for wildlife. Land capability involves consideration of the risks of land damage from erosion and other causes and the difficulties in land use owing to physical land characteristics, including climate.
land capability class
One of the eight classes of land in the land capability classification of the USDA Natural Resource Conservation Service (USDA,1993); distinguished according to the risk of land damage or the difficulty of land use; they include:Land suitable for cultivation and other uses.Class I Soils that have few limitations restricting their use.Class II Soils that have some limitations, reducing the choice of plants or requiring moderate conservation practices.Class III Soils that have severe limitations that reduce the choice of plants or require special conservation practices, or both.Class IV Soils that have very severe limitations that restrict the choice of plants, require very careful management, or both.Land generally not suitable for cultivation (without major treatment).Class V Soils that have little or no erosion hazard, but that have other limitations, impractical to remove, that limit their use largely to pasture, range, woodland, or wildlife food and cover.Class VI Soils that have severe limitations that make them generally unsuited for cultivation and limit their use largely to pasture or range, woodland, or wildlife food and cover.Class VII Soils that have very severe limitations that make them unsuited to cultivation and that restricts their use largely to grazing, woodland, or wildlife. Class VIII Soils and landforms that preclude their use for commercial plant production and restrict their use to recreation, wildlife, water supply, oraesthetic purposes.
land capability subclass Groups of capability units within classes of the land capability classification that have the same kinds of dominant limitations for agricultural use as a result of soil and climate. Some soils are subject to erosion if they are not protected, while others are naturally wet and must be drained if crops are to be grown. Some soils are shallow or droughty or have other soil deficiencies. Still other soils occur in areas where climate limits their use. The four kinds of limitations recognized at the subclass level are: risks of erosion, designated by the symbol (e); wetness, drainage, or overflow (w); other root zone limitations (s); and climatic limitations(c). The subclass provides the map user informationabout both the degree and kind of limitation. Capability Class I has no subclasses. (USDA, 1993)
land evaluation The process of assessment of land performance when the land is used for specific purposes.
land farming A process of bioremediation or biodegradation in which wastes are incorporated into soil and allowed to decompose via naturally occurring microbial activity.
land grading Land smoothing; a process whereby the surface of the soil is shaped to improve water runoff.
land planing Refer to tillage, land planing.
land-surface form The description of a given terrain unit based on empirical analysis of the land surface rather than interpretation of genetic factors. Surface form may be expressed quantitatively in terms of vertical and planimetric slope-class distribution, local and absolute relief, and patterns of terrain features such as interfluve crests, drainage lines, or escarpments (Hawley and Parsons, 1980).
landfill (refer to sanitary landfill). Compare dump.
landform Any physical, recognizable form or feature on the earth’s surface, having a characteristic shape, internal composition and produced by natural causes; a distinct individual produced by a set of processes. Landforms can span a large range in size (e.g., dune encompasses a number of features including parabolic dune which can be several tens-of-meters long, and seif dune that can be up to 100 km long. Landforms provide an empirical description of similar portions of the earth’s surface( Jackson, 1997; Schoeneberger and Wysocki, personal communication, 2013). Compare anthropogenic features.
landforming Refer to tillage, landforming.
landscape [soils] A broad or unique area comprised of an assemblage or collection of landforms that define a general geomorphic form or setting (e.g., mountain range, lake plain, lava plateau, or loess hills). Landforms within a landscape are spatially associated, but may vary in formation processes and age (Schoeneberger and Wysocki, personal communication, 2013). Compare anthroscape.
landslide A general, encompassing term for most types of mass movement landforms and processes characterized by the downslope transport and outward deposition of soil and rock materials caused by gravitational forces that may or may involve water saturated materials. Names of landslide types generally reflect the dominant process and/or the resultant landform. The main operational categories of mass movement are fall (rockfall, debris fall, soilearth fall), topple (rock topple, debris topple, earth topple), slide (rotational landslide, block glide, debris slide, lateral spread), flow [rock fragment flow (especially rockfall avalanche), debris avalanche, debris flow (e.g., lahar), earthflow, (creep, mudflow)], and complex landslides (Varnes, 1978; Schoeneberger and Wysocki, personal communication, 2013). Compare solifluction.
lapilli Non or slightly vesicular pyroclastics, 2.0 to 76 mm in at least one dimension, with an apparent specific gravity of 2.0 or more. Compare ash [volcanic], volcanic block, cinders, tephra.
LaPlace Equation The parial differential equation representing steady-state groundwater flow.
lateral moraine A ridge-like moraine carried on and deposited at the side margin of a valley glacier. It is composed chiefly of rock fragments derived from valley walls by glacial abrasion and plucking, or colluvial accumulation from adjacent slopes ( Jackson, 1997).
lateral spread [mass movement] A category of mass movement processes, associated sediments (lateral spread deposit) or resultant landforms characterized by a very rapid spread dominated by lateral movement in a soil or fractured rock mass resulting from liquefaction or plastic flow of underlying materials; also called spread. Types of lateral spreads can be specified based on the dominant particle size of sediments (i.e., debris spread, earth spread, rock spread ( Jackson, 1997; Schoeneberger and Wysocki, personal communication, 2013; Varnes, 1978). Compare fall, topple, slide, flow, complex landslide, landslide.
Lateritic soil [soil classification] (obsolete; not used in soil taxonomy) A suborder of zonal soils formed in warm, temperate, and tropical regions and including the following great soils groups: Yellow Podzolic, Red Podzolic, Yellowish-Brown Lateritic, and Lateritic (Thorp and Smith, 1949).
lath box Refer to irrigation, spile.
Latosol [soil classification] (obsolete; not used in soil taxonomy) A suborder of zonal soils including soils formed under forested, tropical, humid conditions and characterized by low silica-sesquioxide ratios of the clay fractions, low base-exchange capacity, low activity of the clay, low content of most primary minerals, low content of soluble constituents, a high degree of aggregate stability, and usually having a red color (Kellogg, 1950).
lattice A regular geometric arrangement of points in a plane or in space. Lattice is used to represent the distribution of repeating atoms or groups of atoms in a crystalline substance. A lattice is a mathematical concept. Atomic substitutions take place in a structure and not in a lattice. Compare phyllosilicate mineral terminology.
lattice energy The energy required to separate the ions of a crystal to an infinite distance.
lava A general term for a molten extrusive, also the rock solidified from it ( Jackson, 1997).
lava dome A rounded or irregular mound, hill or small mountain composed of lava congealed over a volcanic vent on the flanks or within a crater or caldera. Typically composed of silica-rich volcanic rocks (e.g., rhyolite, dacite) with admixtures of obsidian, agglomerate, volcanic breccia, etc.). The lava may be uniform or varied in color and texture ( Jackson, 1997; Schoeneberger and Wysocki, personal communication, 2013; Sigurdsson, 2000). Also called a resurgent dome .
lava field An area covered primarily by lava flows whose terrain can be rough and broken or relatively smooth; it can include vent structures (e.g., small cinder cones, spatter cones, etc.), surface flow structures (e.g., pressure ridges, tumuli, etc.) and small, intermittent areas covered with pyroclastics (Schoeneberger and Wysocki, personal communication, 2013). Compare lava plain, volcanic field.
lava channel Refer to lava trench.
lava flow A solidified body of rock formed from the lateral, surficial outpouring of molten lava from a vent or fissure, often lobate in form. Compare aa lava flow, lava flow unit, pahoehoe lava flow ( Jackson, 1997).
lava flow unit A separate, distinct lobe of lava that issues from the main body of a lava flow; a specific outpouring of lava, a few centimeters to several meters thick and of variable lateral extent, that forms a subdivision within a single flow; also called flow unit. A series of overlapping lava flow-units together comprise a single lava flow (Green and Short, 1971; Jackson, 1997). Compare lava flow.
lava flows [soil survey] A miscellaneous area (map unit) applied to lava flow units virtually devoid of plants (other than lichens), and with little or no earthy material cover (USDA, 1993).
lava plain A broad area of nearly level land, that can be localized but is commonly hundreds of square kilometers in extent, covered by a relatively thin succession of primarily basaltic lava flows resulting from fissure eruptions ( Jackson, 1997; Schoeneberger and Wysocki, personal communication, 2013). Compare lava plateau, lava field, volcanic field.
lava plateau A broad elevated tableland or flat-topped highland, that may be localized but commonly is many hundreds or thousands of square kilometers in extent, underlain by a thick succession of basaltic lava flows resulting from fissure eruptions (e.g., Columbia River Plateau; Jackson, 1997). Compare lava plain, lava field.
lava trench A natural surface channel in a lava flow that never had a roof, formed by the surficial draining of molten lava rather than by erosion from running water; also called lava channel (Schoeneberger and Wysocki, personal communication, 2013). Compare mawae, lava tube.
lava tube A natural, hollow tunnel beneath the surface of a solidified lava flow through which the lava flow was fed; the tunnel was left empty when the molten lava drained out (Macdonald and Abbott, 1970; Jackson, 1997).
law of diminishing returns When other factors in production do not change, successive increases in the input of one factor will not proportionately increase product yield.
law of the minimum Refer to Liebig's law.
layer Refer to phyllosilicate mineral terminology.
layer silicate minerals Synonym phyllosilicates. Compare Appendix I, Table A3.
layer charge Magnitude of charge per formula unit of a clay that is balanced by ions of opposite charge external to the unit layer. Compare phyllosilicate mineral terminology.
leachate Liquids that have percolated through a soil and that contain substances in solution or suspension.
leachate collection system A drainage collection system to capture leachate generated from an area for monitoring or treatment purposes, commonly used with landfills.
leaching The removal of soluble materials from one zone in soil to another via water movement in the profile. Compare eluviation.
leaching fraction The fraction of infiltrated irrigation water that percolates below the root zone.
leaching requirement The leaching fraction necessary to keep soil salinity, chloride, or sodium (the choice being that which is most demanding) from exceeding a tolerance level of the crop in question. It applies to steady-state or long-term average conditions.
lectins Plant proteins that have a high affinity for specific sugar residues.
ledge (a) A narrow shelf or projection of rock, much longer than wide, formed on a rock wall or cliff face, as along a coast by differential wave action on softer rocks; erosion is by combined biological and chemical weathering. (b) A rocky outcrop; solid rock. (c) A shelflike quarry exposure or natural rock outcrop ( Jackson, 1997). Compare structural bench.
lee (adj.) Said of a side or slope that faces away from an advancing glacier or ice sheet, and facing the downstream (“down-ice”) side of a glacier and relatively protected from its abrasive action ( Jackson, 1997). Compare stoss, stoss and lee, crag and tail.
leghemoglobin An iron-containing, red pigment(s) produced in root nodules during the symbiotic association between Bradyrhizobium or Rhizobium and legumes. The pigment resembles but is not identical to mammalian hemoglobin.
length of run Refer to irrigation, length of run.
lepidocrocite FeOOH, an orange iron oxide mineral that is found in mottles and concretions of wet soils.
lessivage Translocation of silicate clay particles within a soil, usually downward translocation is implied, and the mechanism of movement is usually infiltrating water.
levee [streams] An artificial or natural embankment built along the margin of a watercourse or an arm of the sea, to protect land from inundation or to confine streamflow to its channel ( Jackson, 1997). Compare artificial levee, natural levee.
leveled land A land area, usually a field, that has been mechanically flattened or smoothed to facilitate management practices such as flood irrigation; as a result the natural soil has been partially or completely modified (e.g., truncated or buried; Schoeneberger and Wysocki, personal communication, 2013).
Liebig’s law (of the Minimum) The growth and reproduction of an organism is dependent on the nutrient substance that is available in minimum quantity.
lift Refer to tillage, lift.
light soil (colloquial) A coarse-textured soil; a soil with a low drawbar pull and hence easy to cultivate. Compare coarse textured and soil texture. Contrast to heavy soil.
lime requirement The amount of liming material as calcium carbonate equivalent required to change a volume of soil to a specified state with respect to pH or soluble Al content.
lime concretion An aggregate of precipitated calcium carbonate, or of other material cemented by precipitated calcium carbonate.
lime, agricultural A soil amendment containing calcium carbonate, magnesium carbonate, and other materials, used to neutralize soil acidity and furnish calcium and magnesium for plant growth. Classification including calcium carbonate equivalent and limits in lime particle size is usually prescribed by law or regulation.
lime-pan (not preferred) Use caliche, petrocalcic. A hardened layer cemented by calcium carbonate. Better term may be caliche.
limestone A sedimentary rock consisting chiefly (more than 50%) of calcium carbonate, primarily in the form of calcite. Limestones are usually formed by a combination of organic and inorganic processes and include chemical and clastic (soluble and insoluble) constituents; many contain fossils (Hawley and Parsons, 1980).
limestone pavement (not preferred) Use pavement karst.
limited irrigation Refer to irrigation, limited irrigation.
limnic material One of the common components of organic soils and includes both organic and inorganic materials that were either (i) deposited in water by precipitation or through the action of aquatic organisms, or (ii) derived from underwater and floating aquatic plants and aquatic animals.
limonite A general “field” term for various brown to yellowish brown, amorphous to cryptocrystalline hydrous ferric oxides that are an undetermined mixture of goethite, hematite, and lepidocrocite formed by weathering and iron oxidation from iron-bearing, rocks and minerals (Schoeneberger and Wysocki, personal communication, 2013; Jackson, 1997).
line source Refer to irrigation, irrigation line source.
lineament A natural occurring linear surface feature.
linear gilgai A type of gilgai dominated by parallel micro-low troughs separated by low ridges (micro-highs) and oriented perpendicular to the topographic contour (i.e., up and down slopes); the prevailing type of gilgai on sloping terrain (slopes > 8%; Schoeneberger and Wysocki, personal communication, 2013). Compare circular gilgai, elliptical gilgai, gilgai.
liquid limit The minimum mass water content at which a small sample of soil will barely flow under a standard treatment. Synonymous with “upper plastic limit.” Compare Atterberg limits, consistency, plastic limit, and plasticity number.
liquifaction Process involved in slope failures when saturated soil is shaken by earthquakes.
lister planting Refer to tillage, lister planting.
listing Refer to tillage, listing.
lithic contact A boundary between soil and continuous, coherent, underlying material. The underlying material must be sufficiently coherent to make hand-digging with a spade impractical. If a single mineral, its hardness is 3 (Mohs scale), and gravel-size chunks that do not disperse with 15 hours shaking in water or sodium hexametaphosphate solution.
lithification The conversion of unconsolidated sediment into a coherent and solid rock, involving processes such as cementation, compaction, desiccation, crystallization, recrystallization, and compression. It may occur concurrently with, shortly after, or long after deposition (Hawley and Parsons, 1980).
lithiophorite (Al,Li)MnO2(OH)2. A black manganese oxide that is common in iron-manganese nodules of acid soils. It has a layer structure.
lithologic (adjective) Pertaining to the physical character of a rock (Hawley and Parson, 1980).
lithologic discontinuity Zone within the pedo-stratigraphic column that represents a change in lithology or sediment type. It may also mark a zone of nondeposition or erosion. Soil horizons below a lithologic discontinuity are designated as such by adding a “2” in front of the horizon designation (for the second parent material), for example, 2Bt. If two lithologic discontinuities are present, a “3” is used for the third parent material, counting from the surface downward.
lithorelict A micromorphological feature derived from the parent rock that can be recognized by its rock structure and fabric.
lithosequence A group of related soils that differ, one from the other, in certain properties primarily as a result of differences in the parent material as a soil-forming factor.
Lithosols [soil classification] (obsolete; Not used in soil taxonomy) A great soil group of azonal soils characterized by an incomplete solum or no clearly expressed soil morphology and consisting of freshly and imperfectly weathered rock or rock fragments (Baldwin, et al., 1938).
litter The surface layer of the forest floor that is not in an advanced stage of decomposition, usually consisting of freshly fallen leaves, needles, twigs, stems, bark, and fruits.
load carrying capacity A measure of the ability of the soil to support tractors and other vehicles.
loam A soil textural class. Compare soil texture.
loamy (a) Texture group consisting of coarse sandy loam, sandy loam, fine sandy loam, very fine sandy loam, loam, silt loam, silt, clay loam, sandy clay loam, and silty clay loam soil textures. Compare soil texture.(b) Family particle-size class for soils with textures finer than very fine sandy loam but <35% clay and <35% rock fragments in upper subsoil horizons.
loamy coarse sand A soil textural class. Compare soil texture.
loamy fine sand A soil textural class. Compare soil texture.
loamy sand A soil textural class. Compare soil texture.
loamy very fine sand A soil textural class. Compare soil texture.
local relief An informal term referring to the collective, relative differences in elevation of a land surface between drainageways or local depressions and adjacent elevated Landforms (on a local scale; Schoeneberger and Wysocki, personal communication, 2013). Compare relief, Microrelief.
lodgment till A subglacial till deposited by an active glacier (flowing ice) characterized by dense, fissile or platy structure and containing rock fragments with their long axes oriented generally parallel to the direction of ice flow. Local bedrock generally dominates the rock fragment composition and fragments exhibit striations or facets ( Jackson, 1997). Compare till, supraglacial till, flow till, melt-out till.
loess Material transported and deposited by wind and consisting of predominantly silt-sized particles. Commonly a loess deposit thins and the mean-particle size decreases as distance from the source area increases. Loess sources are dominantly from either glacial meltwaters (i.e., “cold loess”) or from non-glacial, arid environments, such as deserts (i.e., ”hot loess”). Several types of loess deposits can be recognized based on mineralogical composition (calcareous loess, non-calcareous loess; Schoeneberger and Wysocki, personal communication, 2013).
loess bluff A bluff composed of a thick deposit of coarse loess, formed immediately adjacent to the edges of flood plains, as along the Mississippi River valley or China. Sometimes referred to as a bluff formation (not preferred; Schoeneberger and Wysocki, personal communication, 2013).
loess hill A hill composed of thick deposits of loess, as in Iowa, Missouri, Nebraska and the Palouse Hills of Washington and Idaho (Schoeneberger and Wysocki, personal communication, 2013).
log landing A comparatively level area, usually with road access, constructed or cut into steeper slopes and used for sorting logs during timber harvest operations (Schoeneberger and Wysocki, personal communication, 2013). Compare skid trail.
long run-out landslide (not recommended; use rockfall avalanche).
longitudinal dune A long, narrow sand dune, usually symmetrical in cross profile, oriented parallel to the prevailing wind direction; it is wider and steeper on the windward side but tapers to a point on the lee side. It commonly forms behind an obstacle in an area where sand is abundant and the wind is strong and constant. Such dunes can be a few meters high and up to 100 km long ( Jackson, 1997). Compare seif dune, transverse dune.
longshore bar A low, elongate sand ridge, built chiefly by wave action, occurring at some distance from, and extending generally parallel with, the shoreline, and submerged at least by high tides, and typically separated from the beach by an intervening trough ( Jackson, 1997).
loose A soil consistence term. Compare consistence.
loosening Refer to tillage, loosening.
louderback A hill or ridge composed of a lava flow remnant that caps or is exposed in a tilted fault block and bounded by a dip slope. Used as evidence of block faulting in Basin-and-Range terrain (western USA; Jackson, 1997). Compare hogback.
low hill A generic name for an elevated, generally rounded land surface with low local relief, rising between 30 m (100 ft.) to as much as 90 m (approx. 300 ft.) above surrounding lowlands (Schoeneberger and Wysocki, personal communication, 2013). Compare high hill, hill, hillock.
low marsh (not preferred; use mud flat). The flat, usually bare ground situated seaward of a salt marsh and regularly covered and uncovered by the tide; for example, a mud flat ( Jackson, 1997).
low-center polygon A polygon whose center is depressed relative to its boundary (National Research Council of Canada, 1988). Compare high-center polygon.
Low-Humic Gley soil [soil classification](obsolete; not used in soil taxonomy). A great-group of chronically wet, reduced soils with low humic content (Thorp and Smith, 1949).
lower plastic limit Refer to plastic limit.
lowland (a) An informal, generic, imprecise term for low-lying land or an extensive region of low-lying land, especially near a coast and including the extended plains or country lying not far above tide level. (b) (not preferred) A generic, imprecise term for a landscape of low, comparatively level ground of a region or local area, in contrast with the adjacent higher country. (c) (not recommended – use valley, bolson, etc.) A generic term for a large valley (Schoeneberger and Wysocki, personal communication, 2013). Compare upland.
lowland vs. upland soils (not recommended) Extremely generic terms commonly used to denote landscape positions or soils that are subject to flooding or that are deliberately flooded for rice production vs. those that are not.
lowmoor bog A bog that is at or only slightly above the water table, on which it depends for accumulation and preservation of peat (chiefly the remains of sedges, reeds, shrubs, and various mosses; Jackson, 1997). Compare highmoor bog, raised bog.
luxury uptake The absorption of nutrients by plants in excess of that quantity needed for optimum growth. Luxury concentrations during early growth may be utilized in later growth.
lysimeter (a) A device for measuring percolation and leaching losses from soil under controlled conditions.(b) A device for measuring gains (irrigation, precipitation, and condensation) and losses (evapotranspiration) from soil. (Refe to Weihermuller et al., 2007).suctioncup-porous tube containing a small tube to extract water from soil under vacuumsuctionplateseparate porous extraction plates inserted into a frame connected to a tube for water extraction under a vacuum.panlysimeter(zero tension) passive water samplers that freely collect percolating soil water.wicksamplersampling devices which sample unsaturated soil water by the gravitational potential using an inert wick material, and pulling water from the wick by hanging a water column that maintains the lower soil boundary at a pressure less than stmospheric.columnlysimetercontainers of disturbed or undisturbed soil to represent natural crop production, may be free drainage or drain under suction to col-lect leachate.