**[(R -- 9) - GLOSSARY]{.underline}**

> **A**cequia: Historical community ditch, found throughout the state
> but predominantly in the mountainous areas of Northern New Mexico.
>
> Agronomy: The science of utilizing plants for food, fuel, feed, and
> fiber.
>
> Anion: Negatively-charged particle.
>
> Application efficiency (E~a~): The ratio of the average depth of
> irrigation water infiltrated and stored in the root zone to the
> average depth of water applied, expressed as a percentage - also
> referred to as AE.
>
> Application rate: Term generally used in sprinkler irrigation to
> describe the rate at water is applied to a given area - usually
> expressed in inches per hour.
>
> Available soil water: The difference between actual water content of a
> soil and the water held by the soil at permanent wilting point.
>
> Available water capacity (AWC): The portion of water in the soil
> profile that can be readily absorbed by plant roots of most crops,
> expressed in inches per inch, inches per foot, or total inches for the
> specified soil depth. It is the amount of water stored in the soil
> between field capacity (FC) and permanent wilting point (WP). It also
> called available water holding capacity (AWHC).
>
> **B**laney-Criddle Method: An air temperature based method to estimate
> crop Evapotranspiration.
>
> Bulk density: Mass of dry soil per unit volume, determined by drying
> to a constant weight at 105^o^ C, usually expressed as gm/cc or
> lb/ft^3^.
>
> **C**ation exchange capacity (CEC): The sum of exchangeable cations
> (usually Ca, Mg, K, Na, Al, H) that the soil constituent or other
> material can absorb at a specific pH. Usually expressed in milli
> equivalents (meq) per 100 grams of soil at neutrality (pH=7.0).
>
> Cation: Positively charged particle.
>
> Chemigation: Application of chemicals to crops through an irrigation
> system by mixing them with irrigation water.
>
> Conservation crop rotation: Growing crops in a recurring rotation on
> the same field to maintain or improve soil organic matter, reduce
> water and wind erosion, select crops for irrigation water management
> or salinity management, manage nutrients and pests, provide food for
> domestic livestock, and provide food and cover for wildlife.
>
> Conservation management system: A system which addresses soil, water,
> air, plant, and animal resource concerns.
>
> Consumptive use: See Evapotranspiration.
>
> Crop coefficient (K~c~): A factor used to modify potential
> evapotranspiration as follows: (1) Ratio between crop
> evapotranspiration (Et~c~) and the reference crop (ET~o~) when the
> crop is grown in large fields under optimum growing conditions (Et~c~
> = K~c~ x ET~o~), or (2) the ration of the actual crop
> Evapotranspiration to its potential Evapotranspiration.
>
> **D**enitrification: Process occurring naturally in soil, where
> bacteria break down nitrates to give nitrogen gas, which returns to
> the atmosphere.
>
> Distribution uniformity (DU): The measure of the uniformity of
> irrigation water over a field. NRCS typically uses DU of the lower
> one-quarter which is the ration of the average of the lowest
> one-fourth of measurements of irrigation water infiltrated to the
> average depth of water infiltrated, expressed as a decimal. Each value
> represents and equal area.
>
> **E**lectrical conductivity (EC): A measure of the ability of the soil
> water to transfer an electrical charge. It is used as an indicator for
> the estimation of salt concentration, measured in mmhos/cm (dS/m at
> 77^o^F (25^o^C).
>
> Electrical resistance blocks: A block made of various material
> containing electrical contact wires that is placed in the soils at
> selected depths to measure soil moisture content. Electrical
> resistance, as affected by moisture in the block, is read with a
> meter.
>
> Energy: The capacity of a physical system to perform work.
>
> Evapotranspiration (ET): The combination of water transpired from
> vegetation and evaporated from soil and plant surfaces - sometimes
> called consumptive use (CU).
>
> **F**ield capacity: The amount of water retained by a soil after it
> has been saturated and has drained freely by gravity. It can be
> expressed as inches, inches per inch, bars suction, or percent of
> total available water.
>
> Flood irrigation, wild flooding: A surface irrigation system where
> water is applied to the soil surface without flow controls, such as
> furrows, borders (including dikes), or corrugations.
>
> Furrow irrigation: A surface irrigation system where water is applied
> to small channels or furrows to guide water down slope and prevent
> cross flow - called rill or corrugation irrigation in some areas.
>
> **G**ravitational water: Soil water that moves into, through, or out
> of the soil under the influence of gravity.
>
> **H**iflow turnout: A field turnout structure that delivers a high
> rate of water, typically up to 20 cfs. The idea is to deliver water
> across the field in the minimum amount of time in order to have
> similar opportunity time across the entire filed. Laser leveled fields
> are essential.
>
> **I**nfiltration, infiltration rate: The downward flow of water into
> the soil at the air-soil interface. The rate at which water enters
> soil is called intake rate or infiltration rate.
>
> Irrigation efficiency (E~i~): The ration of the average depth of
> irrigation water beneficially used to the average depth applied,
> expressed as a percentage. It includes satisfying the soil water
> deficit, leaching requirement for salinity control, and meeting other
> plant needs - generally used to express overall field or farm
> efficiency, or seasonal irrigation efficiency.
>
> Irrigation water management (IWM): Managing water resources
> (precipitation, applied irrigation water, humidity) to optimize water
> use by the plant. Soil and plant resources must be considered.
>
> **L**aser leveling: Shaping of the surface of the soil to planned
> elevations and grades with the use of laser controlled leveling
> equipment.
>
> Leaching fraction: The ratio of the depth of subsurface drainage water
> (deep percolation) to the depth of infiltrated irrigation water -
> determined by the leaching requirement.
>
> Legume: A legume is any of the thousands of plant species in the
> legume family, *Leguminosae.* Legumes have seed pods that, when ripe,
> split along both sides. Beans, lentils, peanuts, peas, and soybeans
> are some of the common legumes consumed by humans
>
> LEPA: Low energy precision application. A soil, water, and plant
> management regime where precision down-in-crop application of water is
> made on the soil surface at the point of use. Application devices are
> located in the crop canopy on drop tubes mounted on low pressure
> center pivot or linear move sprinkler irrigation systems - generally
> limited to circular plantings on less than 1% slopes and no
> translocation of applied water. Furrow dikes, good soil condition, and
> crop residue are usually required to control water translocation.
>
> LPIC: A low pressure in-canopy system that may or may not include a
> complete soil, water, and plant management regime as required by LEPA.
> Application devices are located in the crop canopy with drop tubes
> mounted on low pressure center pivot or linear move systems. Limited
> water translocation within the field and some minor non-uniformity of
> water application usually exists.
>
> **M**AD: Management allowed depletion is the planned soil moisture
> deficit at the time of irrigation. It can be expressed as the
> percentage of available soil water capacity or as a depth of water
> that has been depleted from the root zone.
>
> Measuring: The process of determining the amount of water used with
> the focus being on managing the use.
>
> Metering: The process of measuring water with the legal implications
> of reporting use.
>
> Microirrigation: The frequent application of small quantities of water
> as drops, tiny streams, or miniature spray through emitters or
> applicators place along a water delivery line (tubing). The
> microirrigaiton method encompasses a number of systems or concepts,
> such as bubbler, drip, trickle, line source, mist, or spray.
>
> **N**et irrigation: The actual amount of applied water stored in the
> soil for plant use or moved through the soil for leaching salts. Also
> includes water applied for crop quality and temperature modification.
> Application losses, such as evaporation, runoff, and deep percolation
> are not included - generally measured in inches of water depth
> applied.
>
> Nutrient management: Managing the application rate, method, and timing
> of fertilizers and soil amendments, including manure, to optimize crop
> use and reduce pollution of ground and surface water.
>
> **O**rganic Matter: Soil organic matter consists of a variety of
> components. These include, in varying proportions and many
> intermediate stages: raw plant residues and microorganisms (1 to 10
> per cent), \"active\" organic traction (10 to 40 per cent), and
> resistant or stable organic matter (40 to 60 per cent) also referred
> to as humus.
>
> **P**an coefficient: A factor to relate actual evapotranspiration of a
> crop to the rate water evaporates from a free water surface in a
> shallow pan. The coefficient usually changes by crop growth stage.
>
> Pest Management: Utilizing environmentally sensitive prevention,
> avoidance, monitoring and suppression strategies, to manage weeds,
> insects, diseases, animals, and other organisms, that directly or
> indirectly cause damage or annoyance.
>
> Petiole: The stalk of a leaf, attaching the blade to the stem.
>
> pH: A measure of the acidity or alkalinity of a solution, numerically
> equal to 7 for neutral solutions, increasing with increasing
> alkalinity and decreasing with increasing acidity. The pH scale
> commonly in use ranges from 0 to 14.
>
> Power: The time rate at which work is done or energy is transferred.
>
> PPM: Parts per million
>
> PWP: Permanent wilting point. The moisture percentage, on a dry weight
> basis, at which a plant can no longer obtain sufficient moisture from
> the soil to satisfy water requirements resulting in a dead plant.
> Classically, 15 atmospheres soil moisture tension is used to estimate
> PWP.
>
> **R**eplogle flume: Also known as a ramp flume. A modified
> broad-crested weir located in a short flume, lined ditch, or pipeline
> that causes a drop in the hydraulic grade line, for measuring water
> flow rates. With open channel flow, there is one critical surface,
> which is level. Very little head loss is required to accurately
> measure water.
>
> Root zone: Depth of soil that plant roots readily penetrate and in
> which predominant root activity occurs.
>
> **S**aline soil: A non-sodic soil containing sufficient soluble salts
> to impair its productivity for growing most crops. The electrical
> conductivity (EC~e~) of the saturation extract is greater than 4
> mmhos/cm. and the exchangeable sodium percentage (ESP) is less than
> 15; i.e., non-sodic. The principle ions are chloride, sulfate, small
> amounts of bicarbonate, and occasionally some nitrate. Sensitive
> plants are affected at lower salinity and tolerant plants are not
> affected until the salinity is higher.
>
> Saline-sodic soil: Soil containing both sufficient soluble salts and
> exchangeable sodium to interfere with the growth of most crops. The
> electrical conductivity (EC~e~) of the saturation extract is greater
> than 4 mmhos/cm. and the exchangeable sodium percentage (ESP) is
> greater than or equal to 15. This soil is difficult to leach because
> the clay colloids are dispersed.
>
> Salinity: The concentration of dissolved mineral salt in water and
> soil on a unit volume or weight basis.
>
> SAR: Sodium adsorption ratio. A relation between soluble sodium and
> soluble divalent cations that can be used to predict the exchangeable
> sodium percentage (ESP) of soil equilibrated with a given solution
> defined as follows: SAR = Na / ((Ca + Mg) / 2)^1/2^. Na is sodium, Ca
> is calcium, and Mg is magnesium. Concentrations are expressed in moles
> per liter.
>
> SAR, adjusted: Also shown as "Adj. RNa". The sodium adsorption ratio
> of water adjusted for the precipitation or dissolution of Ca^2+^ and
> Mg^2+^ that is expected to occur where water reacts with alkaline
> earth carbonates within a soil. Numerically, it is obtained by
> multiplying the sodium adsorption ration by the value (1 + 8.4 --
> pH~c~\*), where pH~c~ is the theoretical calculation of the pH of the
> water in contact with lime and in equilibrium with soil CO~2~.
>
> SDI: Subsurface drip irrigation. Applying irrigation water below the
> ground surface by using a buried perforated or porous pipe system that
> discharges water directly into the plant root zone. It is the
> predominant form of trickle/drip irrigation in New Mexico.
>
> Sprinkle irrigation: Method of irrigation in which water is sprayed or
> sprinkled through the air to plant or ground surface. Various systems
> exist to include: Periodic move, fixed/solid-set,
> continuous/self-move, boom, center pivot, corner pivot, gun type,
> lateral move / linear move, portable hand move, side move, side roll,
> solid set / fixed set, towed, and traveler.
>
> Stress irrigation: Management of irrigation water to apply less than
> enough water to satisfy the soil-water deficiency in the entire root
> zone. Preferred term is limited irrigation or deficit irrigation.
>
> **T**DS: Total dissolved solids. The total dissolved mineral
> constituents of water.
>
> Tensiometer: instrument, consisting of a porous cup filled with water
> and connected to a manometer of vacuum gauge to measure the soil-water
> metric potential.
>
> Transmissivity: A measure of the capability of the entire thickness of
> an aquifer to transmit water.
>
> Transpiration: The process of plant water uptake and use, beginning
> with absorption through the roots and ending with transpiration at the
> leaf surfaces.
>
> Trickle irrigation: a microirrigation system (low pressure and low
> volume) wherein water is applied to the soil surface as drops or small
> streams through emitters. Preferred term is drip irrigation.
>
> **V**alve: A device installed in conjunction with a pipeline to
> control flow that includes: Air relief, air vacuum / air relief,
> backflow prevention, ball, butterfly, check, drain, float, gate,
> globe, pressure relief, solenoid, vacuum relief, alfalfa, orchard, and
> surge.
>
> Volatilization: The conversion of a chemical substance from a liquid
> or solid state to a gaseous or vapor state.
>
> **W**HC: Water holding capacity. Total amount of water held in the
> soil between field capacity (FC) and oven dry moisture level,
> expressed in inches per inch, inches per foot, or total inches for a
> specified depth.
>
> Water Quality: The biological, chemical and physical characteristics
> of water and its general composition. These attributes affect water\'s
> ability to sustain life and its suitability for consumption and other
> designated uses.
>
> Water table: The upper surface of a saturated zone below the soil
> surface where the water is at atmospheric pressure.
>
> Wilting point: See PWP or Permanent wilting point.