Glossary of Natural Resource Restoration Terms

These terms appear throughout the OR&R Web site.

Adventitious roots	Roots that develop from some part of a vascular plant other than the seed.
Aerobic	A condition where molecular oxygen is a part of the environment.
Allochthonous	Material that is imported into an ecological system from outside that system; usually refers to organic material and/or nutrients and minerals.
Alluvial plain	The floodplain of a river, where the soils are alluvial deposits carried in by the overflowing river.
Alluvium, Alluvial soil	Soil composed primarily of eroded material such as sand, silt, or clay that has been deposited on land or on the bottom of water bodies by rivers and streams overflowing their banks.
Ambient monitoring	Monitoring within natural systems (e.g., lakes, rivers, estuaries, wetlands) to determine existing conditions.
Anadromous	Species that spawn (breed and lay eggs) in freshwater environments but spend at least part of their life in marine waters. Examples include salmon, river herring (alewife), and striped bass.
Anaerobic	Occurring or living without oxygen present.
Annual	A plant whose life cycle is completed in one year or one season.
Anoxic	Without oxygen.
Anthropogenic	Having to do with or caused by humans
Areal cover	A measure of dominance that defines the degree to which aboveground portions of plants cover the ground surface.
Autochthonous	Material that is produced within the ecological system e.g., organic material produced by photosynthesis.
Benthic	Animals dwelling on the bottom of a water body. These organisms inhabit the sediment on lake, river, or ocean bottoms, as well as the sediment in marshes, tidal flats, and other wetlands.
Bioassay	A laboratory test that uses organisms to evaluate whether a sample is toxic.
Biological effects	Biological effects are measurements indicating that the health of animals living in the area (or evaluated in laboratory tests) has been adversely affected.
Biomagnify	The accumulation of certain chemicals (such as mercury and PCBs) biomagnifies (increases) as they pass through the food chain. This means that a low amount of mercury might be present in fish that eat plants, but higher amounts will accumulate in fish or birds that eat fish. Adverse effects are more likely to occur in birds or fish that eat other animals.
Bottomland	Lowland along streams and rivers, usually on alluvial floodplains that is periodically flooded.
Bottomland hardwood forest	Term used principally in the southeastern and eastern U.S. to mean a mesic riparian forested ecosystem along a higher order stream or river that is subject to intermittent-to-frequent flooding from that stream or river; dominated by oaks and other deciduous hardwood tree species.
Catadromous	Species that spawn (breed and lay eggs) in marine waters but spend at least part of their lives in a freshwater environment. An example is the American eel.
CERCLA	CERCLA, or the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 created the Superfund and the National Priorities List (NPL).
Delineation	Technique of determining an exact boundary of a wetland.  Used for identifying jurisdictional wetlands in the U.S.
Eat-out	A major wetland vegetation removal by herbivory, often by geese or muskrats.
Emergent plant	A rooted herbaceous plant that has parts extending above a water surface.
Emergent wetland	A wetland class dominated by emergent plants; includes marshes and wet meadows.
ERL	Below the level of Effects Range Low (ERL), contaminants in sediment are not likely to have adverse effects on animals that live in sediment.
ERM	Above the level of Effects Range Median (ERM), contaminants in sediment probably have adverse effects on animals that live in sediment.
Estuarine	Present, living or thriving in an estuary.
Estuarine wetlands	Tidal wetlands in low wave-energy environments where the salinity of the water is greater than 0.5 part per thousand and is variable owing to evaporation and the mixing of saltwater and freshwater; tidal wetlands of coastal rivers and embayments, salt marshes, mangrove swamps, and tidal flats.
Estuary	General location where rivers meet the sea and freshwater mixes with saltwater.  Estuaries often contain salt-marshes and other wetlands, which are important habitat for many species.
Facultative	Adapted equally to either wet or dry conditions.  Typically used in the context of vegetation adapted to growing in saturated soils or upland soils.
Fill material	Any material placed in an area to increase surface elevation.
Flood duration	The amount of time that a wetland is in standing water.
Flood frequency	The average number of times that a wetland is flooded during a given period.
Forage	Organisms that serve as food. Small fish are forage for larger fish and for fish-eating (piscivorous) birds.
GIS	Geographic Information System. GIS is used to join electronic files (databases) containing environmental measurements taken at a specific location, to maps showing geographic features. This approach allows scientists to show large amounts of data from specific locations on a map showing landscape features such as wetlands and land use.
Gleying	Development of black, gray, greenish, or blue-gray color in soils when flooded.
Habitat	The place where a plant or animal species naturally lives and grows; or characteristics of the soil, water, and biologic community (other plants and animals) that make this possible.
Halophile	"Salt-loving" organisms.
Halophyte	Salt-tolerant plants.
Hectare	One hectare is equal to 10,000 square meters, or 2.471 acres.
High marsh	Upper zone of a salt marsh that is flooded irregularly and generally is located between mean high water and extreme high water.  Called inland salt marsh along the Gulf of Mexico.
Hydric soils	Soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper depths.
Hydrogeomorphic Classification (HGM)	Wetland classification system based on type and direction of hydrologic conditions, local geomorphology, and climate.
Hydroperiod	The seasonal pattern of the water level of a wetland, which approximates the hydrologic signature of each wetland type.
Hydrophyte	Plant adapted to wet conditions.
Hydrophytic vegetation	Plant community dominated by hydrophytes.
Hypoxia	Waters with dissolved oxygen less than 2 mg/L.
Injury	Harm or adverse effects to aquatic organisms and the habitats they require to complete their life cycle.
Intertidal	Flooded periodically with tidal waters.
Jurisdictional wetland	Term used in the U.S. to refer to wetlands that fall under the jurisdiction of federal laws for the purpose of permit issuance or other legal matters.
Lacustrine	Pertaining to lakes or lake shores.
Littoral	Zone between high and low tide in coastal waters or the shoreline of a freshwater lake.
Lotic	Pertaining to running water e.g., rivers and streams.
Low marsh	Intertidal or lower marsh in salt marsh that is located in the intertidal zone and is flooded daily.
Marsh	A frequently or continually inundated wetland characterized by emergent herbaceous vegetation adapted to saturated soil conditions.
Mineral soil	Soil that contains less than 20-35 percent organic matter.
Mitigate	To lessen or compensate for an impact.  Used here in the context of mitigating wetland loss by restoring or creating wetlands.
No net loss	Wetland policy in the U.S. that began in the late 1980s and means that if wetlands are lost they must be replaced so that there is no "net loss" of wetlands overall.
NPL	The National Priorities List identifies locations throughout the U.S. where hazardous wastes have been found in the environment and the initial evaluation shows a significant risk of harm to human health or the environment. NPL sites are frequently called "Superfund" sites, because Superfund money can be used by the Environmental Protection Agency (EPA) to investigate and clean up these sites.
Obligate	In the context of wetlands, the term generally refers to plants requiring saturated soils.
Organic soil	Soil that has more than 12-18 percent organic carbon, depending on clay content.
Palustrine wetlands	Non-tidal wetlands including open water bodies of less than 20 acres in which water is less than 2 meters deep; includes marshes, wet meadows, fens, playas, potholes, pocosins, bogs, swamps, and shallow ponds; most wetlands are classified as Palustrine.
Playa	An arid-to semiarid-region wetland that has distinct wet and dry seasons.  Term used in the southwestern U.S. for marsh-like ponds similar to potholes, but with a different geologic origin.
Pothole	Shallow marsh-like pond.
Propagules	The shoot, seed or other method that plants use to spread or propagate (reproduce).
Reference wetland	Natural wetland used as a reference or control site to judge the condition of another created, restored, or impacted wetland.
Remediation	Also known as clean up, remediation is taking action to reduce, isolate, or remove contamination from an environment with the goal of preventing exposure to people or animals. Examples include dredging to remove contaminated sediment, or capping to prevent contaminated sediment from contacting benthic organisms.
Restoration	To return a site to an approximation of its condition before alteration.  In the Superfund cleanup process, restoration usually follows remediation.
Riparian	Pertaining to the bank of a body of flowing water; the land adjacent to a river or stream that is, at least periodically, influenced by flooding.
Riprap	A rubble sustaining wall, often used along shorelines to prevent erosion.
Runoff	Unchannelized surface water flow.
Spawning	To release and fertilize eggs, as done by a number of aquatic species (fish, oysters, etc.) to reproduce.
Stream order	A numerical system that classifies stream and river segments by size according to the order of its tributaries.
Subsidence	Sinking of ground level, caused by natural and artificial settling over time.
Subtidal	Permanently flooded with tidal waters.
Superfund	The Superfund is money collected from a special tax on chemical feedstocks and raw petroleum. When a responsible party can not pay, Superfund money can be used by EPA to investigate, evaluate, and cleanup the hazardous waste sites identified on the NPL.
Tributary	A stream that dishcharges into a larger stream, river, lake, or other water body.
Trustee for natural resources	A trustee for natural resources has the responsibility to care for, protect, and restore native organisms and their habitat on behalf of current and future generations of Americans. NOAA is a trustee for natural resources in coastal and marine areas (for example, migratory fish and marine mammals).
Watershed	All the land and tributaries draining to a body of water.
Wet meadow	Grassland with waterlogged soil near the surface but without standing water for most of the year.
Wetlands	Areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and similar areas.
Wetland creation	Construction of a wetland on a non-wetland site.  Typically, a wetland is created by excavating upland soils to elevations that will support wetland species by establishing and maintaining an appropriate hydrologic regime.
Wetland enhancement	Improving the structure or function of an existing wetland.
Wetland reallocation or replacement	When an existing wetland is converted to a different type of wetland e.g., changing an emergent wetland to a pond, which converts the habitat from one type to another.
Wetland restoration	Returning a wetland ecosystem to a close approximation of its condition prior to disturbance; it is not necessary that a wetland be returned to a pristine condition.

For more information You may also want to refer to our list of commonly used acronyms.

EPA Terms of Environment: Glossary, Abbreviations, and Acronyms "Terms Of Environment" defines in non-technical language the more commonly used environmental terms appearing in EPA publications, news releases, and other Agency documents available to the general public, students, the media, and Agency employees. [leaves OR&R site]

Coastal Hazardous Waste Site Report Acronyms and Abbreviations Here are acronyms and abbreviations that appear in NOAA's Coastal Hazardous Waste Site Reports.