Renewable Energy terms starting with M

99 terms

Maar A volcanic crater that is produced by an explosion in an area of low relief, is generally more or less circular, and often contains a lake, pond, or marsh.
Macrophyte (aquatic) An aquatic plant that is large enough to be observed with the naked eye. It grows in or near water.
Mafic (or maphic) A term used to describe an igneous rock that has a large percentage of dark-colored minerals such as amphibole, pyroxene, and olivine.
Magma Molten or partially molten rock at temperatures ranging from 1,260 F to 2,880 F (700 C to 1600 C).
Maintenance area Any geographic region of the United States previously designated nonattainment pursuant to the CAA Amendments of 1990 and subsequently redesignated to…
Major source A source that emits, or has the potential to emit, a pollutant regulated under the Clean Air Act in excess of a specified rate in a nonattainment area.
Mammals A group of air-breathing animals whose skin is more or less covered with hair or fur and who have mammary glands.
Management activities Planned activities initiated by land managers to meet the desired future condition for an area.
Management area Management areas are specific geographical areas defined by a forest plan. Each management area has a set of objectives and a management prescription…
Management indicator species Species selected as ecological indicators. The welfare of a management indicator species is presumed to be an indicator of the welfare of other species…
Management plan A plan guiding overall management of an area administered by a federal or state agency.
mannan The polymer of mannose with a repeating unit of C6H10O5. Can be hydrolyzed to mannose. (Source: Voet, D.; Voet, J. G. Biochemistry.
mannose A hexose component of many polysaccharides, occasionally used as a carbohydrate source in plant tissue culture media.
Mano A stone with a flat side that was primarily held in one's hand or hands and used to grind edible substances, typically corn, grains, and nut meats.
Mantle The main bulk of the Earth, between the crust and core, ranging from depths of about 40 to 3,480 kilometers.
Mantle hot spot A region of continental or oceanic crust below which a mantle plume causes melting of the overlying crust, resulting in a broad regional topographic swell…
Marsh An area of low-lying wetlands dominated by grasslike plants.
mash A mixture of grain and other ingredients with water to prepare wort for brewing operations.
Mass Burn Facility A type of municipal solid waste (MSW) incineration facility in which MSW is burned with only minor presorting to remove oversize, hazardous, or explosive…
mass closure (%) The percent by weight of the total samples extracted from the biomass sample compared to the weight of the original sample.
Materials recovery facility (MRF) A recycling facility for municipal solid waste.
Maximum Contaminant Level (MCL) The highest level of a contaminant that is allowed in drinking water. MCLs ensure that drinking water does not pose either a short-term or long-term…
Maximum output See Nameplate capacity
MBF One thousand board feet of lumber.
MCDB See moisture content, dry basis.
MCL See Maximum contaminant level
Mean A statistics term. The average value in a set of measurements. The mean is the sum of a set of numbers divided by how many numbers are in the set.
Mean annual increment The annual average growth rate for a tree, computed over its entire life cycle.
Mean sea level (MSL) The arithmetic mean of hourly water elevations observed over a specific 19-year tidal epoch.
Median household income Divides households into two equal segments, with one-half of households earning less than the median household income and the other half earning more.
Median housing value Divides housing units into two equal segments, one-half of housing units less than median housing value and the other half valued more.
Megafauna A number of species of presently extinct mammals including mammoths and mastodons.
Megawatt One thousand kilowatts, or 1 million watts; standard measure of electric power plant generating capacity.
Megawatt (MW) A measure of instantaneous electric power consumption or production. Equal to one thousand KW.
Megawatt electrical (MWe) One million watts of electrical energy; a measure of electrical power capacity, use in PEIS is synonymous with MW.
Merchantable Logs from which at least of the volume can be converted into sound grades of lumber ("standard and better" framing lumber).
Mesa A broad, flat-topped elevation with one or more steeply-sloping to vertical sides.
Mesic habitat A habitat type characterized by the presence of a moderate amount of moisture or water. Compare: hydric; opposite: xeric.
Mesophilic An optimum temperature for bacterial growth in an enclosed digester (25° to 40°C).
Mesozoic An era of geologic time between the Paleozoic and the Cenozoic, spanning the time between 251 and 65 million years ago.
metabolism (meh-TA-boh-lih-zum) The total of all chemical changes that take place in a cell or an organism.
Metamorphic rock A sedimentary or igneous rock that has been changed by pressure, heat, or chemical action.
Metate A portable stone slab upon which seeds and other grains are milled with a mano using a push-pull, back-and-forth motion. See also Mano
Methane A colorless, odorless, tasteless gas composed of one molecule of Carbon and four of hydrogen, which is highly flammable.
Methanogen A methane-producing organism.
Methanol Methyl alcohol having the chemical formula CH30H. Methanol is usually produced by chemical conversion at high temperatures and pressures. Wood alcohol.
methanol (wood alcohol) (CH3OH) An alcohol formed by catalytically combining carbon monoxide with hydrogen in a 1:2 ratio under high temperature and pressure.
Methyl tertiary butyl ether (MTBE) An ether manufactured by reacting methanol and isobutylene. MTBE has high octane and low volatility. Used as a fuel oxygenate.
Metric Ton (or tonne) 1000 kilograms. 1 metric ton = 2,204.62 lb = 1.023 short tons.
mg/l Milligrams per liter.
MGD Million gallons per day.
Microalgae Unicellular, photosynthetic aquatic plants.
Microbiotic soil crusts See Biological soil crusts
Micron One thousandth of a millimeter.
microorganism An organism that can be seen only through a microscope. Microorganisms include bacteria, protozoa, algae, and fungi.
Microphytic soil crusts See Biological soil crusts
Microsite A small area within an environment with unique features, conditions, or characteristics relative to the surrounding area.
Mid seral species Shade intolerant species, primarily Douglas-fir trees and vine maple shrubs. These species typically follow the early seral species in natural succession.
Mid seral treatment A treatment in which a stand of predominately mid seral species will be established.
Migration corridor A route followed by animals such as big game, birds, or fish when traveling between winter and summer habitats.
Migratory Bird Treaty Act (MBTA) The MBTA implements various treaties and conventions between the United States, and Canada, Japan, Mexico, and the former Soviet Union for the protection…
Military Training Route (MTR) A designated corridor of airspace with defined vertical and lateral dimensions established for conducting military flight training at airspeeds in excess…
Mill A common monetary measure equal to one-thousandth of a dollar or a tenth of a cent.
Mill residue Wood and bark residues produced in processing logs into lumber, plywood, and paper.
Mill/kWh A common method of pricing electricity. Tenths of a cent per kilowatt hour.
Milligauss (mG) A unit of measure for magnetic fields.
Millsite mining claim Claim on nonmineral land for processing ore from a mining claim.
Mineral A nutrient required to maintain health.
Mineral Leasing Act of 1920 (MLA) Authorizes the agency to issue rights-of-way grants for oil and gas gathering and distribution pipelines and related facilities not already authorized…
Mineral materials Widespread deposits of common clay, sand, gravel, or stone which are not subject to disposal under the 1872 Mining Law, as amended.
Mining claim That portion of the public mineral lands which a miner, for mining purposes, takes and holds in accordance with the mining laws.
Mining water use Water use during quarrying rocks and extracting minerals from the land.
Minority population Includes Hispanic, American Indian, or Alaskan Native; Asian; Native Hawaiian or Other Pacific Islander; Black (not of Hispanic origin) or African…
Miocene An epoch of the upper Tertiary period, 23 to 5.3 million years ago.
Mirror A reflecting surface of various physical shapes (parabolic, nearly flat, or flat) used to reflect and/or concentrate the sun's energy to specific…
Mitigation Term usually used to refer to various changes or improvements made in a home; for instance, to reduce the average level of radon.
Mitigation (measures) Methods or actions that will reduce adverse impacts from solar facility development.
MMBF One million board feet.
MMBtu One million British thermal units.
module The smallest self-contained, environmentally protected structure housing interconnected photovoltaic cells and providing a single dc electrical output…
Moisture The amount of water and other components present in the biomass sample that are volatilized at 105°C. (Source: Ehrman, T.
Moisture Content (MC) The weight of the water contained in wood, usually expressed as a percentage of weight, either oven-dry or as received.
Moisture content, dry basis (MCDB) Moisture content expressed as a percentage of the weight of oven-dry wood. weight of wet sample - weight of dry sample…
Moisture content, wet basis (MCWB) Moisture content expressed as a percentage of the weight of wood as-received. Expressed as: weight of wet sample - weight of dry sample…
moisture free basis Biomass composition and chemical analysis data is typically reported on a moisture free or dry weight basis.
Molten salts Mixtures of sodium nitrate and potassium nitrate in various proportions that are used as a heat transfer or heat storage medium in CSP Solar Energy…
Monoculture The agricultural practice of cultivating crops consisting of genetically similar organisms.
monosaccharide A simple sugar (e.g. glucose, fructose). See:.
Montane The highland area located below the subalpine zone. Montane regions generally have cooler temperatures, and often have higher rainfall than the adjacent…
Mortality The state of being mortal (destined to die). Mortality also refers to the death rate, or the number of deaths in a certain group of people in a certain…
Mortar A stone bowl or bowl-shaped depression (such as in a rock) in which seeds, berries, nuts, meats, and other items are ground or pulverized with a pestle…
Mosses Low-growing, nonvascular plants that are common to moist habitats.
mscf One thousand standard cubic feet.
Multijunction solar cell A photovoltaic device comprised of two or more semiconductor materials or cell junctions, each capable of producing electricity with the photovoltaic…
Multiple use A combination of balanced and diverse resource uses that takes into account the long-term needs of future generations for renewable and nonrenewable…
Multiple Use Classes Class C is for lands designated either as wilderness or for wilderness study areas. These lands are managed to protect their wilderness values.
Multiple use management Coordinated management of the various surface and subsurface resources, without permanent impairment of the productivity of the land, that will best meet…
municipal solid waste Any organic matter, including sewage, industrial, and commercial wastes, from municipal waste collection systems.
Municipal Solid Waste (MSW) Waste material from households and businesses in a community that is not regulated as hazardous.