Sec 2-1 glossary of environmental terms Flashcards
Acid Rain
Precipitation with pH levels much below average as a result of the
formation of sulfuric acid in polluted air.
Active layer
The surface layer in a permafrost environment, which is
characterized by freezing and thawing on a seasonal basis
Aggradation
Filling in of a stream channel with sediment, usually associated with
low discharges and/or heave sediment loads.
Alluvial Fan
A fen-shaped deposit of sediment laid down by a stream at the foot
of a slope; very common features in dry regions, where Streams deposit their sediment load as they lose discharge downstream.
Aquifer
Any subsurface material that holds a relatively large quantity of groundwater and is able to transmit that water readily.
Backshore
The zone behind the shore - between the beach berm and the
backshore slope
Backshore slope
The bank or bluff landward of the shore that is comprised of <i>in situ
</i>material
Backswamp
A low, wet area in the floodplain, often located behind a levee.
bankfull discharge
The flow of a river when the water surface has reached bank level.
Baseflow
The portion of streamflow contributed by groundwater; it is a
steady flow that is slow to change even during rainless periods
Bay-mouth bar
A ribbon of sand
deposited across the mouth of a bay.
Berm
A low
mound that forms along sandy beaches; also used to describe elongated mounds constructed along water features and site borders.
Boreal Forest
Subarctic
conifer forests of North America and Eurasia; florlsticaily homogeneous forests dominated by fir, spruce, and tamarack; in Russia, it is called <i>taiga</i>.
Buildable Land Units
Parcels
of various size within a designated project area that are suitable for development as defined by a prescribed development program
Carrying capacity
The level of development density or use an environment is able to
support without suffering undesirable or irreversible degradation.
Choropleth map
A map comprised of areas of any size or shape representing
qualitative phenomena (eg,.soils) or quantitative phenomena (e.g. population); map often has a patchwork appearance
Climate
The representative or general conditions of the atmosphere at a
place on earth; H is more than the average conditions of the
atmosphere, for climate may also include extreme and infrequent
conditions.
Closed Forest
A forest structure with multiple levels of growth from the ground
up; a forest in which undergrowth closes out the area between the
canopy and the ground.
Coastal Dune
A sand dune that forms in coastal areas and is fed by sand from the
beach
Colluvium
An unsorted mix of soil and
mass-movement debris.
Conduction
A
mechanism of heat transfer involving no external motion or mass transport; instead, energy is transferred through the collision of vibrating molecules
Conveyance Zone
The central route of
drainage,
usually a channel and valley, in a drainage basin
Declination
of the sun
The location
(latitude) on earth where the sun on any day is directly overhead; declinations range from 23.27° S latitude to 23.27° N latitude.
Degradation
Scouring and
downcutting of a stream channel, usually associated with high discharges
Design storm
A rainstorm of a given intensity and frequency of recurrence used as the basis for sizing stormwater facilities such as stormsewers.
Detention
A strategy used in stormwater management in which runoffs detained on site to be released later at some prescribed rate.
Development
density
A measure of the intensity of development or land use; defined on the basis of area covered by impervious surface, population, density, or building floor area coverage for example
Drainage
basin
The are that contributes runoff to a stream, river, or lake.
Drainage
density
The number of miles (or km) of stream channels per square mile (or km1) of
land.
Drainage
divide
The border of a drainage basin or watershed where overland separates between adjacent areas.
Drainage network
A system of stream channels usually connected in a hierarchical fashion. See also Principles of stream orders.
Drainfield
The network of pipes or tiles through which wastewater is dispersed into the soil.
Ecosystem
A group of organisms linked together by a flow energy; also a community of organisms and their environment.
Ecotone
The transition zone between two groups, or zones, of vegetation.
Environmental assessment
A preliminary study or review of proposed action (project) and the influence it could have on the environment. Often conducted to determine the need for more detailed environmental impact analysis.
Environmental Impact Statement
A study required by US Federal law for projects (proposed)
involving federal funds to determine types and magnitudes of
impacts that would be expected in the natural and human
environment and the alternative courses of action, including no
action.
Environmental inventory
Compilation and classification of data and information on the
natural and human features in an area proposed for some sort of
planning project.
Ephemeral Stream
A stream without baseflow; one that flows only during or after
rainstorms or snowmelt events.
Erodibility
The relative susceptibility of a soil to erosion.
Erosion
The removal of rock debris by an agency such as moving water,
wind, or glacieis; generally, the sculpting or wearing down of the
land by erosional agents.
Eutrophication
The increase in biomass Of a waterbody leading to infilling of the
basin and the eventual disappearance of open water; sometimes
referred to as the aging process of a waterbody
Evapotranspiration
the loss of water from the soil through evaporation and transpiration.
Feasibility Study
A type of technical planning aimed at identifying the most appropriate use of a site.
Fetch
The distance of open water in one direction across a water body; it is one of the main controls on wave size.
Floodway fringe
the zone designated by the US Federal flood policy as the area in a river valley that would be lightly inundated by the 100-year flood.
Frequency
The term used to express how often a specified event is equaled or exceeded.
Frost wedging
A mechanical weathering process in which water freezes in a crack
and exerts force on the rock, which may result in the breaking of the rock; a very effective weathering process in alpine and polar environments.
Geomorphic System
A physical system comprised of an assemblage of landform linked
together by the flow of water, air, or ice.
Geomorphology
The field of earth science that studies the origin and distribution of
landforms, with special emphasis on the nature of erosional processes;
traditionally,
a field shared by geography and geology.
Grafting
The practice of attaching additional channels to a drainage network; in agricultural areas new channels appear as drainage ditches; in urban areas, as stormsewers.
Greenbelt
A tract of trees s and associated vegetation in urbanized areas; it may
be a park, nature preserve, or part of a transportation corridor.
Albedo
The percentage of Incident radiation reflected by a material. Usage
in earth science is usually limited to shortwave radiation and landscape materials.
Gross sediment transport
The total quantity of sediment transported along a shoreline in some time period, usually a year.
Ground Frost
Frost that penetrates the ground in response to freezing surface temperatures.
Ground sun Angle
The angle formed between a beam of solar radiation and the surface that it strikes in the landscape.
Groundwater
The mass of gravity water that occupies the subsoil and upper bedrock zone; the water occupying the zone saturation b elbow the soil water zone.
Gullying
Soil erosion characterized by the formation of narrow, steep-sided channels etched by rivulets or small streams of water. Gullying can be one of the most serious forms of soil erosion of cropland.
Habitat
The environment with which an organism interacts and from which it gains its resources; habitat is often variable in size, content, and location, changing with the phases in an organism’s life cycle.
Hardpan
A hardened soil layer characterized by the accumulation of colloids and ions.
Hazard assessment
Study and evaluation of the hazard to land use and people from environmental threats such as floods, tornadoes, and earthquakes.
Heat Island
The area or patch of relatively warm air which develops over urbanized areas.
Heat Transfer
The flow of hear within a substance or the exchange of heat between substances by means of conduction, convection, or radiation.
Hillslope processes
The geomorphic processes that erode and shape slopes; mainly mass movements such as soil creep and landslides and runoff processes such as rain-wash and gullying.
Hydrograph
A streamflow graph which shows the change in discharge over time, usually hours or days. See also Hydrograph method.
Hydrograph method
A means of forecasting streamflow by constructing a hydrograph that shows the representative response of a drainage basin to a rainstorm; the use of a ’normalized’ hydrograph for flow forecasting in which the size of the individual storm is filtered out. See also Hydrograph.
Hydrologic Cycle
The planet’s water system, described by the movement of water from the oceans to the atmosphere to the continents and back to the sea.
Hydrometer Method
A technique used to measure the clay content in a soil sample that involves dispersing the clay particles in water and drawing off samples at prescribed time intervals.
In Situ
A term used to indicate that a substance is in place as contrasted with one, such as river sediment, that is in transit.
Interception
The process by which vegetation intercepts rainfall or snow before it reaches the ground.
Interflow
Infiltration water that moves laterally in the soil and seeps into stream channels; in forested areas this water is a major source of stream discharge.
Isopleth map
A map comprised of lines, called isolines, that connect points of equal value.
Land cover
The materials such as vegetation and concrete that cover the ground. See also Land Use.
Landslide
A type of mass movement characterized by the slippage of a body of material over a rapture plane often a sudden and rapid movement.
Land Use
The human activities that characterize an area, i.e. agricultural, industrial, residential.
Latent Heat
The heat released or absorbed when a substance changes phase as from liquid to gas. For water at 0°C, heat is absorbed or released at a rate of 2.5 million joules per kilogram (597 calories per gram) in the liquid /vapor phase change.
Leachate
Fluids that emanate from decomposing waste in a sanitary or chemical landfill.
Levee
A mound of sediment that builds up along a river bank as a result of flood deposition.
Line scanner
A remote sensing device that records signals of reflected radiation in scan lines that sweep perpendicular to the path (flight line) of the aircraft.
Littoral drift
The material that is moved by waves and currents in coastal areas.
Loess
Silt deposits laid down by wind over extensive areas of the midlatitudes during glacial and postglacial times.
Mass Movement
A type of hillslope process characterized by the downslope movement of rock debris under the force of gravity; it includes soil creep, rock fall, landslides, and mudflows; also termed mass wasting.
Meander
A bend or loop in a stream channel.
Meander belt
The width of the train of active meanders in a river valley.
Microclimate
The climate of small spaces such as an inner city, residential area, or mountain valley.
Mitigation
A measure used to lessen the impact of an action.
Montmorillonite
A type of clay that is notable for its capacity to shrink and expand with wetting and drying.
Moraine
The material deposited directly by a glacier; also, the material (load) carried in or on a glacier; as landforms moraines usually have hilly or rolling topography.
Mudflow
A type of mass movement characterized by the downslope flow of a saturated mass of clayey material.
Multispectral scanning system (MSS)
A line-scanning remote sensing system capable of simultaneously recording reflected radiation in several discrete bands (wavelengths).
Net Sediment transport
The balance between the quantities of sediment moved in two (opposite) directions along a shoreline.
Nonpoint Source
Water pollution that emanates from a spatially diffused source such as the atmosphere or agricultural land.
Nutrients
Various types of materials that become dissolved in water and induce plant growth; phosphorus and nitrogen are two of the most effective nutrients in aquatic plants.
Open forest
A forest structure with a strong upper one or two stories and limited undergrowth; a forest that is largely open at ground level.
Open system
A system characterized by a through-flow of material and/or energy; a system to which energy or material is added and released over time.
Opportunities and Constraints
A type of study often carried out in planning projects to determine the principal advantages and drawbacks to a development program proposed for a particular site.
Out flooding
Flooding caused by a stream or river overflowing its banks.
Outwash plain
A fluvioglacial deposit comprised of sand and gravel with a flat or gently sloping surface; usually found in close association with moraines.
Overland flow
Runoff from surfaces on which the intensity of precipitation or snowmelt exceeds the infiltration capacity; also called Horton overland flow, for hydrologist Robert E. Horton.
Oxbow
A crescent-shape lake or pond in a river valley formed in an abandoned segment of channel.
Ozone
One of the minor gases of the atmosphere, a pungent, irritating form of oxygen that performs the important function of absorbing ultraviolet radiation.
Parent material
The paniculate material In which a soil forms; the two types of parent material are residual and transported.
Passive solar collector
A solar collector that operates without the aid of powered machinery.
Peak discharge OR Peak Flow
The maximum flow of a stream or river in response to an event such as a rainstorm or over a period of time such as a year.
Pedon
The smallest geographic unit of soil defined by soil scientists of the U.S. Department of Agriculture
Perennial Stream
A stream that receives inflow of groundwater all year; a stream that has a permanent baseflow.
Periglacial environment
An area where frost-related processes are a major force in shaping the landscape.
Permafrost
A ground-heat condition in which the soil or subsoil is permanently frozen; long-term frozen ground in periglacial environments.
Photo pair
A set of overlapping aerial photographs that are used in stereoscopic interpretation of aerial photographs.
Planned Unit Development (PUD)
A residential planning strategy aimed at increasing the amount undeveloped land or common space by clustering development carefully planned units.
Plume
The stream of exhaust (smoke) emanating from a stack of chimneys.
Point source
Water pollution that emanates from a single source such as sewage plant outfall.
Principles of stream orders
The relationship between stream order and the number of streams per order; the relationship for most drainage nets is an inverse on characterized by many low-order streams and fewer and few streams with increasingly higher orders. See also Stream order
Principal point
The center of an aerial photograph, located at the intersection of lines drawn from the fiducial marks on the photo margin.
Progradation
The process of seaward growth of a shoreline.
Pruning
In hydrology the cutting back of a drainage net by diverting and burying streams; usually associated with Urbanization or agricultural development.
Quadrat sampling
A field sampling technique in which small plots, called quadrats, are laid out in the landscape and from which the sample is drawn.
Radiation
The process by which radiant (electromagnetic) energy is transmitted through free space; the term used to describe electromagnetic energy, as in infrared radiation or shortwave radiation
Rain erosion index
A set of values representing the computed erosive power of rainfall based on total rainfall and the maximum intensity of the thirty minute rainfall.
Rain intensity
The rate of rainfall measured in inches of centimeters of water deposited on the surface per hour or minute
Rainshadow
The rate of rainfall measured in inches or centimeters of water deposited on the surface per hour or minute
Rainsplash
Soil erosion from the impact of raindrops.
Rainwash
Soil erosion by overland flow; erosion by sheets ,of water running over a surface; usually occurs in association with rainsplash; also called wash
Recharge
The replenishment of groundwater with water from the surface.
Recurrence
The number of years on the average that separate events of a specific magnitude, e.g.., the average number of years separating river discharges of a given magnitude or greater.
Regulatory floodway
A zone designated by the US. Federal flood policy as the lowest part of the floodplain where the deepest and most frequent floodflows are conducted.
Relief
The range of topographic elevation within a prescribed area.
Retention
A strategy used in. stormwater management in which runoff is retained on site in basins, underground, or released into the soil.
Runoff
In the broadest sense runoff refers to the flow of water from the land as both surface and subsurface discharge; the more restricted and common use, however, refers to runoff as surface discharge in the form of overland flow and channel flow.
Sapping
An erosional process that usually accompanies gullying in which soil particles, are eroded by water seeping from a bank.
Scatter diagram
A graph characterized by a series of plotted points showing the relationship between two quantitative variables.
Seepage
The process by which groundwater or interflow water seeps from the ground.
Septic Tank
A vat, usually placed underground, used to store wastewater.
Septic system
Specifically, a sewage system that relies on a septic tank to store and/or treat wastewater; generally, an on-site (small-scale) sewage- disposal system that depends on the soil to dispose of wastewater.
Sensitive Environment
Special environments such as wetlands or coastal lands that require protection from development because of their aesthetic and ecological value.
Setback
A terrain used in site planning to indicate the critical distance that a structure or facility should be separated from an edge such as a backshore slope or lake shore.
Shoreland
The discontinuous belt of land around a waterbody that is not drained via stream basins.
Side-Looking airborne radar (SLAR)
The radar system used in remote sensing; so named because the energy pulse is beamed obliquely on the landscape from the side of the aircraft.
Sieve Method
A technique used to separate the various sizes of coarse particles in a soil sample.
Slope Failure
A slope that is unable to maintain itself and fails by mass movement such as a landslide, slump, or similar movement.
Slope Form
The configuration of a slope, e.g. convex, concave, or straight
Slump
A type of mass movement characterized by a back rotational motion along a rupture plane.
Soil Creep
A type of mass movement characterized by a very slow downslope displacement of soil, generally without fracturing of the soil mass; the mechanisms of soil creep include freeze-thaw activity and wetting and dying cycles.
Solar Gain
A general term used to indicate the amount of solar radiation absorbed by a surface or setting in the landscape.
Solar heating
The process of generating heat from absorbed solar radiation; a widely used term in the solar energy literature.
Solstice
The dates when the declination of the sun is at 23.27°N latitude (the Tropic of Cancer) and 23.27°$ latitude (the Tropic of Capricorn)-June 21-22 and December21-22, respectively. These dates are known as the winter and summer solstices, but which is which depends on the hemisphere.
Stream Order
The relative position, or rank, of a stream in a drainage network. Streams without tributaries, usually the small ones, are first-order; streams with two or more first-order tributaries are second-order, and so on
Subarctic Zone
The belt of latitude between 55° and the Arctic and Antarctic circles.
Sun Angle
The angle formed between the beam of incoming solar radiation and a plane at the earth’s surface or a plane of the same altitude anywhere in the atmosphere.
Sun Pocket
A small space designed especially to take advantage of solar radiation and heating.
Surge
A large and often destructive wave caused by intensive atmospheric pressure and strong winds.
Suspended load
The particles (sediment) carried aloft in a stream of wind by turbulent flow, Usually clay-and silt-sized particles.
Temperate forest
A forest of the midlatitude regions that could be described as climatically temperate, e.g.., broadleaf deciduous forests of Europe and North America, comprised of beeches, maples, and oaks.
temperature inversion
An atmospheric condition in which the cold air underlies warm air; inversions are highly stable conditions and thus not conducive to atmospheric mixing.
Thermal gradient
The change in temperature over distance in a substance; usually expressed In degrees Celsius per centimeter or meter.
Threshold
The level or magnitude of a process at which sudden or rapid change is initiated.
Topsoil
The uppermost layer of the soil, characterized by a high organic content; the organic layer of the soil.
Treeline
The upper limit of tree growth on a mountain where forest often .gives way to alpine meadow.
Tundra
Landscape of cold regions, characterized by a light cover of herbaceous plants and underlain by permafrost.
Urban boundary Layer
A general term referring to the layer of air over a city that is strongly influenced by urban activities and forms.
Urban canyon
City street lined with tall buildings; an urban terrain feature that has a pronounced effect on airflow, radiation and microclimate as a whole.
Urban climate
The climate in and around urban areas, it Is usually somewhat warmer, foggier, and less well lighted than the climate of the surrounding region.
Urbanization
The term used to describe the process of urban development, including suburban residential and commercial development.
Wave period
The time it takes a wave to travel the distance of one wavelength.
Wave refraction
The bending of a wave, which results in an approach angle more perpendicular to the shoreline.
Waterable
The. upper boundary of the zone of groundwater, in fine-textured materials It is usually a transition zone rather than a boundary line. The configuration of the water table often approximates that of the overlying terrain.
Wetland
A term generally applied to an area where the ground is permanently wet or wet most of the year and is occupied by water- loving (or tolerant) vegetation such as cattails, mangrove, or cypress.
Windshield Survey
A rapid and general sampling method for vegetation and land use based on observations from a moving automobile.
Zenith
For any location on earth, the point that is directly overhead to an observer. The zenith position of the sun is the one directly overhead.
Zenith Angle
the angle formed between a Sine perpendicular to the earth’s surface (at any location) and the beam of incoming solar radiation (on any date).
