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‘A’ weighting dB(A)

The human ear does not respond uniformly to different frequencies. A-weighting is commonly used to simulate the frequency response of the ear.

Above Ordnance Datum (aOD)

The mean sea level at Newlyn (UK) used as a base measurement on Ordnance Survey Maps for contours.


The structure that supports the end of the bridge or supports and retains the bridge approach.

Acid grassland

Grassland that occurs on acidic soils (pH less than 5.5).

Acoustic deterrent

A system for repelling fish and marine mammals from a region of water using noise.


Materials used in construction, including sand, gravel, crushed stone, slag, or recycled crushed concrete.

Air Quality Management Area (AQMA)

A non-permanent designation created if monitoring reveals that statutory air quality thresholds are being exceeded or will be exceeded in the near future.


Recently hatched salmonid with yoke sac still present.


Single or multi-cellular organisms that photosynthesise.

Alien species

A species that exists outside of its normal distribution.


A proposal for land for housing, industry or other uses within a Local Plan that identifies a specific area of land to be developed within the time period of the plan.


Sediment deposited by a river.

Amber list species

Bird populations in moderate decline or previously in severe decline but are recovering.

Ambient Noise

The all encompassing sound at any point in time.

Amenity grassland

Intensively managed and regularly mown grasslands that are typical of golf courses, sports pitches, playing fields and lawns. These grasslands are typically of low diversity and limited wildlife and landscape value.

Amenity value

Defined as the relative pleasantness of a journey and relates in particular to the exposure of pedestrians and others to traffic.


Larval stage in the life cycle of lamprey.


Any cold blooded animal of the class Amphibia which includes frogs, toads and newts.


Refers to fish that regularly migrate between freshwater and the sea (in both directions), but not for the purpose of breeding, as in anadromous and catadromous species.


Mating embrace in frogs and toads, when eggs are shed into the water and fertilised.

AnaBat detector

Type of bat detector which detects bat echolocation calls via a microphone and stores call frequency and time information on flash memory card for analysis using AnaLook software. Enables identification of bat species and activity type. Can be operated manually or remotely.


Referring to fish that migrate from marine waters upstream to breed in fresh water.

Ancient Woodland Inventory

Aims to list all probable ancient semi-natural woodlands on a county basis together with those woodlands in other ancient categories of lesser woodland nature conservation interest.

Ancient Woodland

Areas of land that appear as wooded on maps dated pre-1750 (in Scotland) and are considered likely to have been continuously wooded from this date.


A flowering plant which has seeds enclosed within an ovary.


Term used to describe various ring or circle shaped objects or openings.


Absence of oxygen.


Caused by humans.


A marine invertebrate of the class Anthozoa, such as a sea anemone or coral.

Area of Great Landscape Value (AGLV)

An area designated by a local authority in development plans as being of outstanding scenic quality and character and requiring special protection against inappropriate forms of development. (The requirement to designate AGLVs is set out in Circular 2/1962).

Area of Outstanding Landscape Quality (AOLQ)

An area designated by a local authority as being of exceptional landscape quality and requiring special protection against inappropriate forms of development.

Appropriate assessment

An assessment of likely impacts associated with a development on a European Protected Site. An Appropriate Assessment is required by law under Regulation 48 of the Habitats Regulations (1994), implementing Article 6(3) of the Habitats Directive (92/43/EEC).


Relating to or containing water.


A body of rock through which appreciable amounts of water can flow.

Arable land

Land that is or can be used for growing crops.


Taxonomic super order comprising true spiders.


An animal phylum which includes jointed-foot invertebrates, for example, insects, spiders, crustaceans and millipedes.

Artificial refuge

A sheet of corrugated metal, carpet tile or other material that is placed on the ground and is typically used to survey for the presence of retiles and amphibians.


An umbrella term for description, analysis and evaluation.


Increase in duration of flow hydrograph with a consequent reduction in peak flow.


Characteristics of an ecological receptor.

Authority area

The area administered by a local authority for example, District Council, City Council or Unitary Authority.

Average Score Per Taxon (ASPT)

The ASPT is calculated by dividing the Biological Monitoring Working Party (BMWP) score of a sample by the number of scoring families that contributed to the BMWP score of that sample.

Backhoe dredger

Hydraulic excavator equipped with a half open shell.


A technique used for determining the territorial boundaries of badger social groups, involving the use of bait laced with coloured plastic pellets.

Balancing pond

Part of a Sustainable Urban Drainage System (SUDS). The purpose of the balancing pond is to contain the surge of water during/after a storm and release it slowly/in a controlled way, thus preventing flooding and potential pollution.


A device used on submersibles to control buoyancy and stability.

Bank toe reinforcement

Strengthening to the base of a river or stream bank to prevent erosion.

Barrier effects

Features such as roads which may impact communities through restriction of movement and habitat alteration, sub-dividing populations with demographic and possibly genetic consequences.


The existing conditions which form the basis or start point of the environmental assessment.

Bathymetric surveys

The measurement and description of underwater depths taken from the water surface.

Beam trawl

A type of fishing net where the mouth of the net is kept open by a beam with shoes or skids fixed at each end, these travelling along the seabed as the net is towed by boat.


Hard rock that lies beneath a superficial cover of soils and sediments.


Of or relating to or happening on the bottom under a body of water.


The flora and fauna found on the bottom of a sea or lake.


The raised bank or path alongside a waterbody.


A heap or pile of something, especially a slag heap.

Best Practicable Means

A feasible approach [to mitigation] having due regard for means/resources/conditions. Defined in the Control of Pollution Act (1974) as measures which are ‘reasonably practicable having regard among other things to local conditions and circumstances, to the current stated of technical knowledge and to financial implications’.


The process by which substances accumulate in the tissues of living organisms with particular reference to toxic substances that accumulate via a food chain.


Biological diversity, or richness of living organisms present in representative communities and populations.


The process by which substances accumulate in the tissues of living organisms with particular reference to toxic substances that accumulate via a food chain.


Biological diversity or species richness of living organisms present in representative communities and populations.

Biodiversity Action Plan (BAP)

Sets objectives, along with measurable targets for the conservation of biodiversity.

Biodiversity Management Plan

Document identifying the actions to be taken to ensure the maintenance and long-term viability of priority species and habitats in a defined site or area, and the parties responsible for these actions.

Biological Monitoring Working Party (BMWP)

A scoring system for measuring water quality using species of macroinvertebrates as biological indicators based on the variability in sensitivity of different invertebrate groups to different pollutants and pollutant types. Using the system pollution sensitive taxa are assigned a higher score than pollutant tolerant taxa. The higher the sum of individual taxon scores, the better quality invertebrate communities and the better the water quality.


An area of uniform environmental conditions with a specific assemblage of plants and animals.


An aquatic mollusc which has a compressed body enclosed within two hinged shells, such as an oyster, mussel, or scallop.

Biological Monitoring Working Party (BMWP) Index

Based on the tolerance of various freshwater macro invertebrates to organic pollution. Each invertebrate family is assigned a score from 1 to 10, depending on their tolerance to pollution. Low scores are given to pollution-tolerant taxa, whilst the pollution-intolerant taxa score highly. Scores are assigned based on the presence of a scoring family in the sample and abundance within families is not considered. The BMWP score is the total of all the scoring families present in a given sample.


An area of soft, wet, peaty ground.


Mobile water tank.

Brackish water

Water that is a mix of salt and freshwater.


A slope or a hillside.


Angular fragments of rock, which occasionally form the basement bed of alluvial (deposited by flowing water) deposits.

Braun-Blanquet Scale

A cover-abundance scale for analysis of vegetation.

Broadleaved woodland

An area of woodland with predominantly deciduous tree species (less than 10% coniferous trees in the canopy).


Industrial or commercial property or land that is abandoned or underused and often environmentally contaminated, especially one considered as a potential site for redevelopment.


Phylum of non-flowering plants, with little or no vascular tissue; includes plants such as true mosses and liverworts.


A natural, undisturbed strip surrounding a development or land disturbance activity or bordering a stream or permanent water body.


An embankment, wall or dam that can be used to minimise noise or alternatively built around an oil tank to contain the contents in the event of spillage.


A small stream.


Retaining, watertight structure.


Refers to a sediment, sedimentary rock, or soil type which is formed from or contains a high proportion of calcium carbonate.

Calcitic veining

Having veins of calcite, a common crystalline form of calcium carbonate (CaCO3).


A beam supported on only one end that carries the load to the support where it is resisted by moment and shear stress.


Refers to a group of marine mammals that includes whales, dolphins and porpoises.


Referring to fish that live in fresh water and breed in the sea.


A pit at an accessible point in a drainage system, used to collect grit and prevent it from blocking in-accessible sections of the system.


The area contributing flow to a point on a drainage system.


A marine mammal of an order including whales and dolphins.

Channel morphology

Physical characteristics of stream channels, such as width/depth ratio and sinuosity, and types of pattern e.g. braided, meandering, straight.

Channel sinuosity

An assessment of the degree of irregularity in the path of a river channel across the landscape; it is measured as the difference between channel length and valley length.


A group of green algae, with the common name ‘stoneworts’.

Chute flow

Term used in river habitat survey (RHS) to describe a low curving fall in contact with the substrate. Often associated with cascades.


Having a pH of 5.5 to 7.4.

Code of Construction Practice (CoCP)

A series of objectives and measures to be applied throughout the construction period by the Contractor to manage and operate the construction works, to maintain satisfactory levels of environmental protection and limit disturbance from construction activities.


Beetles. Taxonomic order including the largest number of species not only in the class of insects (Insecta), but also in the entire animal kingdom (Animalia)


Assemblage of interacting populations that occupy a given area.

Community Conservation Index (CCI)

A conservation indexing protocol for summarising aquatic macroinvertebrate data obtained from inland flowing and still water sites.

Community Severance

Community severance is defined here as the separation of residents from facilities and services they use within their community caused by new or improved roads or by changes in traffic flows.

Community type

The composition of plant species that form a habitat or group of habitats.

Commuting route

A linear route used regularly by individuals of a population of bats for travelling between roosting and foraging habitats.

Compulsory Purchase Order (CPO)

A legal document giving the government (Scottish Ministers) power to compulsorily purchase the areas of land necessary for the construction of the scheme.


The ability or power to conduct or transmit heat, electricity, or sound'. Its units are Siemens per meter [S/m] in SI.

Coniferous woodland

An area of woodland with predominantly coniferous tree species (less than 10% deciduous trees in the canopy).


Preservation or restoration of the natural environment and wildlife.

Conservation Area

Area of special architectural or historic interest, the character or appearance of which it is desirable to preserve or enhance. Designated under section 61 Planning (Listed Buildings and Conservation Areas) (Scotland) Act 1997.

Contaminated land

Land in such condition by reason of substances on or under the land that significant harm is being caused, there is a significant possibility of such harm being caused or pollution of controlled water is being, or likely to be caused’.


Relating to areas that are connected to each other.

Contracting Parties

Partnership or organisation which enters into a binding agreement with one or more other contracting parties.

Controlled Activity Regulations (Scotland) 2005

Controls all engineering activity in or near watercourses.

Core Path

A right of way designated by a Local Authority as being of importance to maintain access and leisure provision.


A taxonomic family of amphipods.


Above-ground otter shelter.

Cover Value Score (CVS)

Method used when carrying out NVC surveys whereby the percentage of a defined area covered by individual species is identified.


Animals that are most active during twilight i.e. at dawn and dusk.


Marks visible in growing and ripening crops, especially via aerial photography, which reflect the differences in the subsoil beneath. For example, parched lines of grass may indicate hidden stone walls or packed stone layers.


Class of arthropods that often have a hard shell covering their bodies, for example, lobsters, shrimps and crabs.




A badger less than four months old or an otter less than one year old.

Cultivation terrace

A sloped area of land that has been built up and made flat to grow plants/crops on.


A metal, wooden, plastic, or concrete conduit through which surface water can flow under or across roads.

Crawler crane

Crane mounted on an undercarriage with a set of tracks (also called crawlers) that provide stability and mobility.

Critical Load

The quantitative estimate of the level of exposure of natural systems to pollutants below which significant harmful effects on specified sensitive elements of the environment do not occur.


The enclosed area of land around a dwelling.


This type of construction involves excavating a trench from the surface, building a tunnel and then backfilling and restoring the ground.

Cyprinid/coarse fishery

Managed fishery for cyprinid (of the carp family of fishes) fish or coarse fish (non-salmonid freshwater fish).


A scale for assessing species abundance.


Part of a stream where the current is slack (very slow).

Decibel (dB)

The range of audible sound pressures is approximately 0.00002 Pa to 00 Pa. Using decibel notation presents this range in a more manageable form, 0 dB to 140 dB.


Sound pressure Level (dB) = 20 log (pt / p0)

where p0 = 2 x 10-5 Pa


Trees and shrubs that shed their leaves annually.


A small population that interbreeds locally but forms part of a larger population, thus the gene pool of the population is restricted.


Refers to fish which live primarily on or near the seabed.


The studying/science of the characteristics of populations, such as size, growth rate etc.


A taxonomic order of insects commonly called earwigs, characterised by membranous wings folded underneath short leathery forewings.


A temporary waiver from a Regulation or a Directive and is normally only granted for a specific purpose and by unanimous agreement of the Council of Ministers and for a limited period.

Designed Landscape

A designed area of landscape which is identified in the Inventory of Gardens and Designed Landscapes (jointly compiled by Scottish Natural Heritage and Historic Scotland).

Detention pond

A place for temporarily storing water which delays the flow of water downstream.


Disintegrated material such as fallen leaf matter or small rock particles that have been worn away from the main rock mass by the erosive action of the river.


Refers to fish that make migrations between the sea and freshwater, these may be in either direction and not necessarily related to spawning.

Diffuse pollution

Contamination and pollution arising from many dispersed and different sources. These sources are often individually minor, but collectively may be significant.


A taxonomic order of myriapods (subphylum of arthropods) that have two pairs of legs on each segment.


A taxonomic order comprising true flies.

Discharge regime

The rate of flow of a river at a particular moment in time, relative to volume and velocity.


To move something from its natural environment.

District Wildlife Sites (DWS)

Local council designation.


Organisms which are active during daylight hours.


Basic igneous rock similar in composition to basalt but with a coarser grain.


The base situation where there are no modifications to the existing road network. May also refer to the minimum modifications, which will necessarily take place in the absence of a proposed scheme.

Domin Scale

A variation of the Braun-Blanquet Scale for describing an area of vegetation.


Term used in hydrology to describe the lowering of reservoir water level or in an aquifer, the change in hydraulic head.


Excavation activity or operation usually carried out at least partly underwater, in shallow seas or fresh water areas with the purpose of gathering up bottom sediments and disposing of them at a different location.


The most common nest type or dwelling place for squirrels comprising a round ball of twigs, leaves and bark, which is frequently built close to the tree trunk or in branch forks to provide shelter from the elements.

Drift deposits

Drift geology overlying bedrock.

Driven shooting

Involves birds being driven over guns by beaters. The guns are stationed in pre-determined positions.

Dune interface

The area where a beach ends and a sand dune plant community starts.

Dung pit

A shallow hole or scrape dug by an animal into which dung and/or urine is deposited.

Duet dual mode bat detector

Duet bat detectors detect bat echolocation calls using a microphone and can be used to identify bat species in "real time" (heterodyne) or by delayed (frequency division) techniques.


Works created through the moving of quantities of soil or unformed rock.


A term relating to law where a right (e.g. a right of way) is held by one person to make limited use of another landowner’s property.


A marine invertebrate of a large taxonomic phylum (Echinodermata) including starfishes, sea urchins, and sea cucumbers.


The use by bats of ultrasonic signals to navigate and locate insect prey.

Ecological Clerk of Works

A qualified ecologist who supervises construction sites, ensuring that ecological impacts are minimised and that the law relating to protected species etc. is complied with.

Ecological receptors

Living organisms, habitats, or natural resources that could be impacted by the construction or operation of the proposed scheme.


The branch of biology concerned with the relations of organisms to one another and to their physical surroundings.


A biological community of organisms interacting with one another and their physical environment.

Edge effect

Processes that characterise habitat fragmentation and the concomitant creation of edges. Habitat conditions (such as degree of humidity and exposure to light or wind) created at or near the more-or-less well-defined boundary between ecosystems, as, for example, between open areas and adjacent forest.


The result of change or changes on specific environmental resources or receptors.


An immature newt in its terrestrial phase.


A fish sampling technique using electric currents and electric fields to control fish movement and/or immobilize fish, allowing capture.


A component part of the landscape or environment (e.g. roods, hedges, woodlands).


A young eel, migrating upstream from the ocean.

Emergent vegetation

The vegetation that grows up from within the water.

Environmental Impact Assessment (EIA)

The process by which information about the environmental effects of a project is evaluated and mitigation measures are identified.

Environmental Management Plan (EMP)

Document which describes the processes to be followed to ensure compliance with environmental legislation and policy and minimise harm to the environment.

Environmental Statement (ES)

Document provided by the Developer to the Competent Authority, containing environmental information required under Article 5 of Directive 85/337/EEC as amended.


Lasting or living for a very short time.


A transition zone between different physiogeographic provinces that involves a sharp, steep elevation differential, characterised by a cliff or steep slope.


Pertaining to an estuary.


A semi-enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea. They are affected by both marine influences, such as tides, waves, and the influx of saline water; and riverine influences, such as flows of fresh water and sediment.

Euryhaline species

Species which can tolerate salinities between 5 and 30 PSU.


A process where water bodies receive excess nutrients that stimulate excessive plant growth. This can lead to effects such as lack of oxygen and reductions in water quality, fish, and other animal populations.


Referring to animals of a particular region or habitat.

Feeding station

A favoured spot where food items are often brought to be eaten and feeding remains as neat piles of chewed lengths of vegetation are evident.


A wetland that, like a bog, has organic soil. In contrast with bogs, fens receive most of their water from the surrounding groundwater, and consequently can be either acidic or alkaline, depending on the surrounding earth. They support a greater variety of plants than bogs, but are often still dominated by peat.


Material deposited by man in ground depression or excavated area.


A juvenile sea trout that has returned to freshwater after being to sea for a short period of time.


A taxonomic phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrate animals.

Flight line

A route, usually along linear or habitat feature, which is used by bats for commuting between landscape features.


Land adjacent to a river, which is subject to regular flooding.


Referring to plants of a particular region or habitat.

Flow regime

Combinations of river discharge and corresponding water levels and their respective (yearly or seasonally) averaged values and characteristic fluctuations around these values.

Fluvial geomorphology

The study of landforms associated with river channels and the sediment processes which form them.


A route between breeding and wintering areas taken by a group of migratory birds.


The geographical extent of an ecological impact.


Searching for food or provisions.


Breaking up of an organisms habitat into smaller fragments that may vary in size.


Bodies of water such as ponds, lakes, rivers and streams containing low concentrations of dissolved salts and other total dissolved solids.


Young fully-formed fish (in salmonids not yet having parr markings).

Fyke net

Small cone-shaped net used to catch fish.


A framework that spans a road or railway track.

Generic mitigation

Measures which are applicable throughout the scheme and which aim to prevent, reduce or offset impacts.


The branch of geology concerned with the structure, origin and development of topographical features of the earth’s crust.

Geophysical survey

Geophysical survey is a non-intrusive pre-construction archaeological evaluation technique that exploits a variety of physical or chemical characteristics of rocks and soils etc, in an attempt to locate underground features of archaeological interest. Types of geophysical survey include magnetometer survey, magnetic susceptibility survey and resistivity survey.


Permeable fabric made of polypropylene/polyester and which has the ability to separate, filter, reinforce, protect or drain.


Pertaining to streams fed by melting glaciers, or to the deposits and landforms produced by such streams.

Glacial Till

Glacial till is that part of glacial drift which was deposited directly by the glacier. It may vary from clays to mixtures of clay, sand, gravel and boulders.

Glass eel

Transparent larval stage of the European eel during migration in the Gulf Stream to the UK coastline prior to migration up rivers and streams.


Even paced section of river or stream with laminar flow.


The measurement of particle grain sizes of sediments.


A female (amphibian or fish) swollen with eggs.

Green Belt

The green belt is an area of countryside around the edge of an urban area where new building is not normally allowed and planning is strictly controlled. The aims are to prevent urban expansion, allow easy access to the countryside and protect attractive landscapes.

Green list species

Bird species with no identified threat to their population status.


Salmon which have spent only one full winter at sea.

Ground Investigation

Exploratory investigation to determine the structure and characteristics of the ground influenced by a development. The collected information is used to establish or predict ground and groundwater behaviour during, and subsequent to, construction.


Verification on the ground of conditions on a site.


Water below the surface of the ground in the saturation zone and in direct contact with the ground or subsoil.


A construction material used to connect sections of pre-cast concrete.


Term most accurately meaning the place in which a species lives, but also used to describe plant communities or agglomerations of plant communities, as used, for example in a Phase 1 Habitat Survey.

Habitat Action Plan

Objectives set by the British government to conserve the biodiversity in given habitats.

Habitat complexity

The sum of factors which interact to dictate environments in which species live.

Habitats Directive

EC Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora.

Habitat fragmentation

Describes the breaking up of an organisms preferred environment/habitat. Occurs naturally through geological processes that alter the layout of the physical environment over long periods of time, or through human activities, such as land conversion.

Habitat isolation

Populations which occupy different habitats within the same area and do not meet.

Habitat Modification Index

An index used to assess the condition of a river corridor based on the biological condition of a sampling point.

Habitat Modification Score

An assessment of the extent of anthropogenic modification to a channel. Larger scores indicate a higher degree of modification.

Habitat Quality Assessment

A measure of the structural diversity of the river. Increasing scores are associated with increasingly complex habitat diversity.

Habitat Suitability Index

A numerical index that represents the capacity of a given habitat to support a selected species.


To become accustomed to a particular situation.


A boundary barrier that does not block the view e.g. where a retaining wall is built into a ditch.


A tube containing a hair-trapping device and baited with nuts, which is placed horizontally on a branch to detect the presence and/or absence of red and grey squirrels.


The behaviour, especially associated with pinnipeds (walruses, seals and sealions), of temporarily leaving the water between periods of foraging activity.

Heavy Goods Vehicle (HGV)

Vehicles with 3 axles (articulated) or 4 or more axles (rigid and articulated).


A taxonomic order of sucking insects comprising true bugs.


Uncultivated land with sandy soil and scrubby vegetation.

Herbaceous vegetation

Plants other than shrubs or trees that do not have persistent parts above ground.


An animal that feeds exclusively on plants.


Referring to reptiles and amphibians.


If something is heterogeneous it is different in kind/type/origin, for example, a riverbed containing silt, gravel and pebbles can be said to be heterogeneous.


Structures that are used by animals to hibernate through the winter, such as log piles, rock piles, vegetation piles, old mammal burrows, tree root complexes and buildings.


Extended period of torpor undertaken during winter.


A sub-class of the phylum Annelida comprising leeches.


Deep underground otter shelter.

Home range

The area within which an animal normally lives.


Something that is composed of parts which are all the same.


The cultivation of flowers, fruit, vegetables or ornamental plants.


Shallow temporary below-ground resting place used by otters.


A taxonomic sub-order of animals that covers many families of water mite.


A chemical compound of hydrogen and carbon.


Of, relating to, or operated by the force of liquid in motion.


The branch of geology that deals with the occurrence, distribution, and effect of ground water.


The exchange of water between the atmosphere, the land and the oceans.


Taxonomic order of the Insecta which includes ants, bees and wasps.


Low levels of oxygen.

Igneous Petrology

The study of igneous rocks, their occurrence, composition, and origin.


When an organism enters a new place/habitat.


Incapable of being mixed.


Any changes attributable to the proposed scheme that have the potential to have environmental effects (i.e. the causes of the effects).


Material that does not allow fluids to pass through it.

Improved grassland

Grasslands that have been so modified by fertilisers, drainage or grazing that they have lost most of the species expected in unimproved grassland.

Incidental sighting

Casual observation of a plant or animal of one or more species recorded by whilst performing a non-relevant ecological survey.

Indicator species

A species that is characteristic of a particular habitat. The disappearance of such a species is an early warning of habitat degradation.


Animals living in the sediments of the ocean floor or river or lake beds


The basic structure or features of a system or organisation.


The place where water is taken into a pipe or conduit (e.g. for cooling water); opposed to outlet.

Intelligent Transport System (ITS)

System to assist in delivering optimum capacity within a safe, efficient and reliable environment and provide local and strategic information to road and public transport users during normal and abnormal conditions.

Inter alia

Among other things.


Alternating layers of different materials in a section of bedded rocks.

Inter-specific competition

Competition for resources between species e.g. red and grey squirrels competing with each other.


The transition zone between mean high water springs and mean low water springs, and includes both land exposed, partially submerged, and fully submerged dependant on the tide and water within this zone.

Intra-specific competition

Competition for resources within a species e.g. red squirrels competing with each other.


Referring to the spaces between sediment grains or in other minute spaces.


Referring to the environment between high and low tide marks (mean high water and mean low water) that is alternately exposed to the air and to the sea.


An animal without a backbone.

Jack-up barge

Self elevating platform.

Jump formwork system

A concrete climbing construction process that rises with the building process to create a vertical seamless wall structure.

Keystone species

Species that have a key role in an ecosystem, affecting many other species within the system. The removal of a keystone species can lead to the extinction of other species within that ecosystem.

Kick sample

A standardised method used to collect aquatic macro-invertebrates with a hand net.


Equivalent Continuous Sound Level. A notional steady sound level which would cause the same A-weighted sound energy to be received as that due to the actual, possibly fluctuating, sound level over a given period of time.


Of or relating to a lake.


A body of comparatively shallow salt or brackish water separated from the deeper sea by a shallow or exposed sandbank, coral reef, or similar feature.


Combination of slope and elevation producing the shape and form of the land surface.

Land Management Contract

Formal agreement betweenthe farmer and the Scottish Government to deliver environmental benefits through a range of land management measures.


Human perception of the land, conditioned by knowledge and identity with a place.


Acquired land which is necessary to construct the scheme and associated infrastructure and to undertake the essential environmental mitigation measures.

Large-masted trees

A tree that produces large seeds e.g. oak, hazel.


An active immature form of an insect or other animal that undergoes metamorphosis, e.g. a caterpillar or tadpole.

Lateral connectivity

Hydrologic connectivity is defined as the condition by which disparate regions on the hillslope are linked via subsurface water flow. Lateral refers to the spatial dimensions of riverine/riparian/floodplain habitats.


A series of pits dug by a badger where faeces (and urine) is deposited or a collection of water vole droppings habitually deposited in a single location typically used to define territorial boundaries.


Taxonomic order of Insecta comprising butterflies and moths.


A group of complex organisms, which are formed from the symbiotic association of a fungus and an alga.


The study of rocks, with particular emphasis on their in terms of their color, texture, and composition.

Listed Building

Building included on the list of buildings of special architectural or historic interest and afforded statutory protection under the ‘Planning (Listed Buildings and Conservation Areas) (Scotland) Act 1997’ and other planning legislation. Classified categories A — C(s).

Littoral sediment

Sediment moved by waves and currents of the littoral zone: the area between high and low water marks.


The common name for members of the plant division Hepatophyta.

Local Landscape Character Area (LLCA)

An area outlined as having distinct characteristics based on landscape features. Derived from regional landscape studies available from SNH.

Local Wildlife Site (LWS)

A non-statutory designation used locally by some local authorities to protect locally valued sites of biological diversity.

Luffing jib tower crane

A tower crane with a hinged jib where its hook will move up and down as the jib moves.

Lying-up site

An area where an otter will rest, usually a holt or couch.


An animal without a backbone that can be seen with the naked eye, for example, snails, waterfleas, shrimps or insects.


An individual alga large enough to be seen easily with the unaided eye.

Made ground

Ground comprised of material deposited by man i.e. not natural.


Size, extent, scale and duration of an impact.

Mammal ledge

A shelf built within a culvert to facilitate mammal passage, accessible at both ends from the bank and the water.


Vegetation at the water’s edge.

Marine Mammal Observer (MMO)

Refers to an observer who conducts visual watches for marine mammals.

Maritime grassland

Maritime habitats are those exposed to the wind and waves around the coast. Maritime grassland occurs on cliffs and slopes in less severely exposed locations.


Low-lying wet land with grassy vegetation; usually is a transition zone between land and water.

Mast trees

Trees that produce nuts.


An area of grassland that has is normally grazed by livestock and/or used for growing hay.

Meander bend

A bend in a sinuous watercourse. Formed when moving water in a valley bottom erodes the outer banks causing the channel to change shape.

Mean Trophic Rank (MTR)

Utilised in surveys of the aquatic plant populations in rivers, MTR uses a scoring system based on species and their recorded abundances at river sites. Each species is allocated a score (its species trophic rank, STR) dependent on its tolerance to eutrophication (enrichment of water with nutrients) then, for a given site, the mean score for all species present is calculated. Tolerant species have a low score, so a low MTR tends to indicate a nutrient-rich river.


Of a moderately rich or productive habitat.


The transformation of one structure into another, most commonly referring to the change undergone by insects and amphibians between embryo and adult life stages.


A population of the same species that is fragmented and exists as loosely connected smaller populations. This occurs naturally but also can be the result of human activities.

Mid channel bars

A non-vegetated accumulation of alluvium (typically gravel or sand) located in a waterbody channel away from the banks, generally found in areas where the channel runs straight, caused by recent channel instability.


The movement (of an animal) from one habitat to another according to the seasons.

Mineral extraction

The removal of a naturally occurring solid formed through geological process that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties.


General term which embraces all those peat-forming ecosystems; bog, fen, carr, muskeg, moor and peatland. Does not include marshes since they are, by definition, non-peat-forming and are seasonally flooded. Mires are subdivided into fens and bogs on the basis of the origin and chemistry of their respective water supplies.


Term used to indicate avoidance, remediation or alleviation of adverse impacts.

Mixed plantation woodland

Planted stands with either broadleaf or conifer species comprising 10-90% of the canopy.


A taxonomic phylum of invertebrates that often have a calcareous shell(s) which at least partly enclose their soft un-segmented bodies.


Land that is used to grow one crop only.


Flora and fauna that live in mountainous regions.

Morphological diversity

Minor variations within a basic body plan or biological form.


An area of intertidal muddy land left exposed at low tide.

Natal den

The small space (usually a holt or couch) used by a female otter to give birth and raise cubs for a period of up to three months.

Natal pond

A pond where eggs are laid and larvae develop.

Natal range

The territory in which the young where born.

National Vegetation Classification (NVC)

A system to describe British vegetation types, whereby each vegetation type has a different ‘code’.


A species occurring naturally, in its normal geographic range.


A member of a phylum of invertebrate animals also known as ribbon worms or proboscis worms.


A family of polychaete worms which are predominantly marine.

Neutral grassland

Grassland communities that grow on neutral soils (pH 5.5 — 7).


The limits, for all important environmental features within which individuals of a species can survive, grow and reproduce.


Refers to any animal that is active at night.


Not originating in, nor characteristic of, a particular area.

Non-motorised users

Pedestrians, cyclists and equestrians.

Non-prime land

Agricultural land of Land Capability for Agriculture (LCA) classes 3.2 to 7.

Non-Statutory Guidance/Organisation

Direction from a professional governing body and not directly through legislation.

Notable species

Species which are below Red Data Book species in terms of threat status.

Nursery area

An area utilised by juvenile animals for protection and food sources.


Taxonomic Order of Insecta comprising dragonflies and damselflies.


The process of compensating for something with something else.


Hermaphroditic terrestrial and aquatic worms having bristles borne singly along the length of the body.

Online pond

Pond that is fed by the river or stream through a natural connecting channel.

Open space

Any land laid out as public parks or used for the purpose of public recreation, or land which is a disused burial ground.


The branch of zoology that deals with the study of birds.

Otter trawl

A fishing net towed by a boat. The horizontal opening of the net is achieved and maintained by angle-towed otter boards (large rectangular ‘boards' of timber or steel) and the vertical opening by a combination of floats on the headrope and weights on the ground line.


The place of discharge e.g. where a sewage pipe discharges into a river.


The branch of science dealing with the recovery and identification of plant remains from geological contexts.


An organism that for at least part of its life derives its food from a living organism of another species (the host).


Young salmon or trout with distinctive thumbprint markings on flanks.

Passage migrants

Birds that are migrating between breeding grounds and/or wintering grounds.

Passive Acoustic Monitoring (PAM)

A method to detect cetaceans by listening for them through hydrophones.


An area of grassland (or other suitable plants) used to feed grazing animals.


Land where plant decomposes only partially and accumulates to form brown to black organic material called peat; the two main types are bogs and fens.


Refers to animals that live in the water column or in the open waters of the sea/ocean rather than the sea floor.


The action of water moving slowly through the pores in soil or permeable rock.


A plant that continues to grow from year to year, sometimes undergoing several years of growth before seeds are produced.


Something that can be penetrated/passed through by something else e.g. soil is permeable to water as the water can pass through it.


A figure expressing acidity or alkalinity on a logarithmic scale of 0 to 14.

Phase 1 Habitat Survey

This identifies the different habitats that are contained within or make up a site, and the key plant species for each of those habitat types.

Phase 2 Habitat Survey

A detailed specialist survey or phytosociological (plant community) study of a habitat within a site. It may utilise analysis of sample vegetation plots (quadrats) following the UK National Vegetation Classification.


A member of the relatively small animal phylum (Phoronida) of worm-shaped animals with a gut that loops and exits the body near the mouth, instead of running the length of the animal.


Movement in response to light.


Biology relating to the function and activity of organisms, rather than their structure.


A heavy stake or post made out of timber, steel, reinforced concrete or pre-tensioned concrete, driven into the ground to support foundations.


The act of installing piles.


A diverse group of semi-aquatic marine mammals comprising the families Odobenidae (the walrus), Otariidae (eared seals, including sea lions and fur seals), and Phocidae (earless seals).


Animals which eat fish.


The outline of an object viewed from above.

Plantation woodland

Woodland of any age that obviously originated from planting.

Plant plug

Any developing plant whose growth cycle is initiated well in advance of its actual planting.


Term used in river habitat survey (RHS) to mean the erosion of a watercourse bank by livestock.

Point bars

Deposits of alluvium found on the inside bank of a meander, they form when alluvium is eroded from the outside bend (cut bank) and deposited on the inside bend of a meander.

Point pollution

A point source of pollution is a single identifiable localised source of air, water, thermal, noise or light pollution.

Policy Advice Note


Supporting document to National Planning Policy Guidelines, which disseminates good practice and provides more specific design advice of a practical nature.


Any member of a group (Class Polychaeta) of segmented marine worms.

Polychlorinated biphenyls (PCBs)

A mixture of chlorinated derivatives of biphenyl banned in 1979. A persistent organic pollutant.

Polycyclic aromatic hydrocarbon (PAH)

Any of a class of carcinogenic organic molecules that consist of three or more benzene rings and are commonly produced by fossil fuel combustion.


Degree to which soil, gravel, sediment or rock is permeated with pores or cavities through which water or air can move.


Migrate entirely within freshwater to spawn, live and feed in freshwater.

Potential couch/holt/hover

Tunnels, cavities or other structures which may be used by otters but which cannot be confirmed as being used in the absence of signs.

Priapulid (penis worm)

A member of a phylum of marine worms with an extensible spiny proboscis.

Predictive System for Multimetrics

The standard method for assessing the biological quality of still waters. The method uses a number of aquatic plant and invertebrate measures, which are combined to give a single value, which represents the waterbody’s overall quality.

Prime agricultural land

Agricultural land of Land Capability for Agriculture (LCA) classes 1, 2 and 3.

Priority habitat

Those which have been identified as being most threatened and requiring actions under the UK Biodiversity Action Plan.

Priority species

Those which have been identified as being most threatened and requiring actions under the UK Biodiversity Action Plan.

Proposed Scheme

The scheme design as reported in Chapter 4 of the ES, and used as the basis for environmental assessment and reporting.

Push net

A frame-mounted fishing net pushed along by hand close to the shore line.


A sample area of known size enclosed within a square frame, inside of which a community of plants/animals is analysed.


Concerned only with the nature of the organism/substance being investigated.


Concerned with the number, as well as nature of the organism/substance being investigated.

Ramsar sites

Internationally important wetland identified for conservation under the Ramsar convention (1971).

Rank vegetation

Grassland or marshes that have not been cut or grazed for some time and have become tall, tussocky and dominated by coarse species of grass.


A stretch or portion between defined limits. The stretch of water visible between bends in a watercourse.


An ecological element that is affected (either directly or indirectly) by an ecological driver that causes a change in an organism, community, ecosystem, or other ecological component of the landscape.


A dwelling, workplace or other building, outdoor space, viewpoint, road or footpath with views which may be changed in character and visual amenity by a proposed development.

Red Data List

The IUCN Red List of Threatened Species™ provides taxonomic, conservation status and distribution information on plants and animals that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those plants and animals that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable).

Red list species

Bird species in severe population decline.


Any structure that provides animals temporarily with a place they can retreat to and feel secure. This can be rock or log piles, dense scrub or mammal burrows

Regionally Important Geological Sites (RIGS)

Sites designated by regional geological groups on locally developed criteria, currently the most important places for geology and geomorphology outside statutorily protected land such as Sites of Special Scientific Interest (SSSI).

Relic woodland

Small remaining section of a large, usually established woodland.

Resectioned/reprofiled channel

Obvious over-deepening of the channel bed resulting from lowering the river bed.

Resectioned/reprofiled bank

Bank modified, often to accommodate flood flow or maintenance machinery. Recent resectioning produces a smooth, uniformly angled bank slope.

Residual impacts

Residual impact means the environmental impact after the provision of mitigation measures, if any.  


A horizontally creeping underground stem which bears roots and leaves and usually persists from season to season


A shallow section of a river/stream where the water is fast-flowing over a gravel/cobble substrate.

Right of way

A public right of way is a defined route which has been used by the general public for at least 20 years and which links two public places (usually public roads).

Riparian habitat

Natural home for plants and animals occurring in a thin strip of land bordering a stream or river.

Riparian zone

The area of habitat that is under the influence of the water body. It includes the transitional area between the water and land, and also extends further back than just the water edges.

River basin characterisation

The process of identifying the type, and all significant pressures on every water body.

River Basin District

The area of land and sea, made up of one or more river basins, together with the associated groundwater and coastal waters, identified by the Water Framework Directive as the main unit for the management of river basins.

River basin management plan

A plan setting out actions required within a river basin to achieve set environmental quality objectives, reviewed on a six yearly basis.

River Habitat Survey (RHS)

A survey to assess the physical structure of freshwater streams and rivers, providing a broad assessment of habitat quality.


RIVPACS (River InVertebrate Prediction And Classification System) is a model that predicts the freshwater macro-invertebrate communities that are expected to occur at a site in the absence of any pollution.


The surface representing the top of the solid geological strata, i.e. below any drift deposits.


Any resting site used by bats including maternity roosts which are used by females and their young, hibernacula which are used during winter hibernation and transitional roosts which may be used at any time.

Rough grassland

Rank or tussocky grassland. May have been drained, grazed, mown or treated with manure but not so improved by fertiliser or herbicides as to have altered the sward composition greatly. Associated with unenclosed uplands, lowlands with poor access or wet areas, and road verges.

Rough pasture

Rough pasture is non-intensive grazing pasture, commonly found on poor soils, especially in hilly areas.

Route corridor

A defined area around the route alignment.


A plant that colonizes disturbed ground. They are often weeds that have a high nutrient requirement and/or are intolerant of competition.


Fast flowing, silent water flow. Standing waves at surface are unbroken.


A defined path used by an animal.


Water that flows over the ground surface to the drainage system. This occurs if the ground is impermeable or if permeable ground is saturated.


A measure of the amount of salts dissolved in water.


Pertaining or belonging to the family Salmonidae (salmon, trout and charr).


An area of coastal habitat that is regularly inundated by seawater.


A plant, fungus or bacterium that gains nourishment directly from dead or decaying organic matter.


Animal dropping.

Scheduled Ancient Monument (SAM)

A monument which has been scheduled by the Scottish Ministers as being of national importance under the terms of the ‘Ancient Monuments and Archaeological Areas Act 1979’.


A depression or hole left when sediment is washed away from the bottom of a river.


A fragment scraped off of something and collected.


Climax vegetation dominated by locally native shrubs, usually less than 5m tall.

Sea kelt

Post spawning adult sea trout.

Secondary impacts

Impacts that are caused by the proposed action and are later in time or farther removed in distance but are still reasonably foreseeable. Secondary impacts may include induced changes to land-use patterns, population density, or growth rate and related effects on natural systems.




Material carried in particles by water or wind and deposited on the land surface or seabed.


The deposition or accumulation of sediment.

Seepage line

The line above which there is no hydrostatic pressure and below which there is hydrostatic pressure.

Seine net

A fishing net which hangs vertically in the water with floats at the top and weights at the bottom edge, the ends being drawn together to encircle the fish.


Organisms that produce their offspring all at once.

Semi-improved grassland

Grassland that has been modified by fertilizers, drainage or intensive grazing. Contain less species diversity than unimproved grasslands.

Semi-natural Ancient Woodland

Areas that appear as wooded on 1860 maps but not maps from 1750 i.e. woodland that appeared between these two dates.

Semi-natural woodland

Woodland that does not obviously originate from planting. The distribution of species will generally reflect the variations in the site and the soil. Planted trees must account for less than 30% of the canopy composition.

Semi-natural habitat

Habitat which has been altered by altered by land management.


Plants and animals that are firmly attached rather than free-moving.


The burrow system of badgers comprising a series of underground tunnels and chambers. There are several categories of sett including a main sett, annexe sett, subsidiary sett and outlier sett.



The separation of communities from facilities and services they use within their community. Alternatively, in relation to agricultural land, the division of plots of land into separate land parcels, potentially affecting access or creating areas that may be impractical for agricultural use.

Sewage fungus

A characteristic community of micro-organisms that often occurs in water with heavy organic pollution.


A barrier of shrubs and trees, which provides protection against the wind and reduces erosion.

Side bar

See Point Bar.


A river with many curves/ bends (meanders).


Member of a phylum containing 144-320 species of bilaterally symmetrical, unsegmented marine worms, commonly called peanut worms.

Site compound

A secure area close to the construction site white provides full site services including storage for equipment, materials and fuel, offices and amenity areas.

Site of Importance to Nature Conservation (SINC)

Non-statutory designation which seeks to protect areas of high wildlife value at a local level.

Sites of Special Scientific Interest (SSSI)

Areas of national importance. The aim of the SSSI network is to maintain an adequate representation of all natural and semi-natural habitats and native species across Britain. The site network is protected under the provisions of Sections 28 and 19 of the Wildlife and Countryside Act 1981 as well as the Amendment Act 1985 and the Environmental Protection Act 1990.

Small-masted tree

A tree that produces small seeds, for example, birch, or Scots pine.


Young salmon migrating to the sea.


A deep hole used for drainage, where rainwater and other waste water drains directly into the ground, without connection to any mains drainage or sewerage pipes.

Social group

A collective term for a family of badgers, comprising usually 4-12 animals.

Soil nailing

Reinforcement and strengthening of the existing ground by installing closely spaced steel bars (nails) into a slope or excavation.


Curving, underground passageway built many years ago, which are usually lined with stone. Their use is not known but it is thought that they were either used for storage of valuable commodities or for ritual purposes.


The process of egg release into the water by aquatic animals.

Special Area of Conservation (SAC)

An area designated under the EC Habitats Directive to ensure that rare, endangered or vulnerable habitats or species of community interest are either maintained at or restored to a favourable conservation status.

candidate Special Landscape Areas (cSLA)

Special Landscape Areas will be designated for their scenic quality, enjoyment, rarity and views. cSLAs will replace existing Areas of Great Landscape Value (AGLVs) when new Local Plans are adopted.

Special Protection Area (SPA)

An area designated under the Wild Birds Directive (Directive74/409/EEC) to protect important bird habitats. Implemented under the Wildlife and Countryside Act 1981. Under the Habitats Directive, all SPAs will be proposed Special Areas of Conservation.

Species Action Plan

UK Biodiversity Action Plans detailing information on the conservation status of 382 species and the actions necessary to achieve the action plan targets.

Specific impact

A forceful consequence or strong effect to something particular or unique.

Species Cover Value

The cover class per plant taxon on an increasing scale between 1 and 9. The value forms part of the calculation of the Mean Trophic Rank

Split hopper barge

Non-mechanical ship or vessel designed to carry materials like rocks, sand and soil.

Spoil ground

An area within a body of water, especially in the sea, where dredged material is deposited.


Otter faeces.


A person or group that has an investment, share or interest in something.

Standing wave

A wave formed by one of three conditions: a narrowing of the riverbed, a steepening of the riverbed, or an increase in the volume of water. In contrast to ocean waves, standing waves don’t generally move much upstream or downstream.


Formal written enactment of a legislative authority that governs a country, city, or county. Typically, statutes command or prohibit something, or declare policy. Statute is often used to distinguish law made by legislative bodies from case law and the regulations issued by Government agencies.

Stenohaline species

Marine species which can tolerate salinities down to 25 practical salinity units (psu).

Strategic Environmental Assessment (SEA)

The process by which information about the environmental effects of proposed plans, policies and programmes are evaluated.

Strategic Transport Project Review (STPR)

A two year review of the Scottish transport network being undertaken by Transport Scotland. It aims to identify and prioritise road, rail and other interventions of national significance, which will be taken forward to improve the network. Through selecting which transport projects of national significance should be progressed, the STPR would also affect regional and local transport networks.


Not causing death directly but has cumulative deleterious effects.


The zone which is permanently covered with seawater.


The base on which a sedentary organism lives or grows.


Referring to marine aquatic environments that are continuously submerged, even at low tide.

Superficial Deposits

The youngest geological deposits formed during the most recent period of geological time, the Quaternary, which extends back 1.8 million years from the present.


A benthic community found in the lower Forth Estuary characterised by both euryhaline and stenohaline species.


The part of the lake, sea or ocean shore that is above the water level but made damp by waves and spray.

Surface water hydrology and flood risk

The study of water on or near the land surface.


The ability to accommodate change arising from the proposed road without adverse effect.

Sustainable drainage systems (SUDS)

A sequence of management practices and control structures designed to drain surface water in a more sustainable fashion than some conventional techniques. Referred to in earlier guidance as ‘Sustainable Urban Drainage Systems’.


An area of wet spongy land that often supports some trees and vegetation but is too wet for cultivation.


Turf; surface layer of ground containing a mat of grass and grass roots.


A term that can be applied to fish, insects, birds and bats as well as microorganisms, such as bacteria, and describes an aggregate of animals of similar size and body orientation, generally moving in the same direction.


An internal gas-filled organ that contributes to the ability of a fish to control its buoyancy.


Plural of taxon.


A taxonomic group of any rank.


The branch of science (biological) concerned with classification.


The environment above the mean high water spring


The minimum intensity or value of a signal etc that will produce a response or specified effect.


The upper, outermost layer of soil.


A rigid frame used as a support.


High concentrations of suspended sediment and particulates in the water column.

Tussocky grassland

Grassland which have no, or only a very sparse, tree and shrub layer, and a ground layer dominated by tussock-forming (clump of) grasses.

Univariant analysis

A statistical analysis that considers only one factor or variable at a time.

Vascular plants

Higher plants, including flowering plants, conifers and ferns. They are characterised by the possession of specialized tissues (vascular tissue) for the translocation of substances around the plant.

Vegetative reproduction

Asexual plant reproduction where plants are formed not from seeds, but from specialized structures of the root, stem or leaf. This is usually accomplished by means of horizontal stems or roots (e.g. runners) which allow the plant to spread over a wider area.


A measure of the speed and direction of an object.


Refers to a type of architecture which is indigenous to a specific time or place.


A bridge that carries a road, railroad etc. over a valley.


A method of driving a pile into the ground using rapid repeated oscillations of the pile.

Visual acuity

Ability to make fine visual discriminations between and among objects in the visual environment.

Visual envelope

The visual envelope illustrates the extent of potential visibility to or from a specific area.


A type of animal communication involving their vocal cords.

Vulnerable groups

Children, elderly and disabled.

Walked-up shooting

Involves people walking across the land using guns and dogs to flush out birds, shooting the birds as they are found.

Waterfowl Habitat

Vegetation and water regimes which facilitate the breeding, nesting, feeding and cover required for the production and proliferation of ducks, geese and other waterfowl.

Water Framework Directive (WFD)

Wide-ranging European environmental legislation (2000/60/EC). Addresses inland surface waters, estuarine and coastal waters and groundwater. The fundamental objective of the WFD is to maintain "high status" of waters where it exists, preventing any deterioration in the existing status of waters and achieving at least "good status" in relation to all waters by 2015.

Water quality

The chemical and biological status of various parameters within the water column and their interactions, for example dissolved oxygen, indicator metals such as dissolved copper, or suspended solids (the movement of which is determined by hydrological process and forms geomorphological landforms).


Any wild bird such as ducks, geese or swans.

Wildlife and Countryside Act 1981 (WCA)

Principal mechanism for wildlife protection in the UK.

Working corridor

Strip of land either side of a proposed development.

Zone of influence

An area along a proposed development over which potential ecological effects extend.

Zone of Theoretical Visibility (ZTV)

Area in which a proposed development would theoretically be visible, based on a ‘bare-ground’ model which takes account of topography but not the screening effects of structures (e.g. buildings), vegetarion (e.g. woodlands). May also be referred to as Zone of Visual Influence.