| Factor |
Category |
Definition |
| Biotope sensitivity |
|
The intolerance of a habitat or community of
species to damage, or death, from an external factor. Defined by the following categories: |
| |
High |
Keystone/dominant species in the biotope or
habitat are likely to be killed/destroyed by the factor under consideration. |
| |
Intermediate |
Some of the keystone/dominant species in a
community may be killed/destroyed by the factor under consideration, the habitat may be
partially destroyed or the viability of a species population or diversity/functionality in
a community will be reduced. |
| |
Low |
Keystone/dominant species in a community or the
habitat being considered are unlikely to be killed/destroyed by the factor under
consideration and the habitat is unlikely to be damaged. However, the viability of a
species population or diversity / functionality in a community will be reduced. |
| |
Not sensitive |
The factor does not have a detectable effect on
structure and functioning of a biotope or the survival or viability of keystone/important
species |
| |
Not sensitive* |
The extent or species richness of a biotope may
be increased or enhanced by the factor. |
| |
Not relevant |
Sensitivity may be assessed as not relevant where
communities and species are protected or physically removed from the factor (for instance
circalittoral communities are unlikely to be effected by increased emergence regime). |
| Benchmarks |
Substratum removal |
All of the substratum occupied by the species or
biotope under consideration is removed. Once the activity or event has stopped (or between
regular events) substratum within the habitat preferences of the original species or
community remains or is deposited. A single event is assumed for assessment. |
| |
Substratum change |
All of the population of a species or an area of
a biotope is smothered by sediment to a depth of 5 cm above the substratum for one month.
Impermeable materials, such as concrete, oil or tar, are likely to have a greater effect [In
the case developments, the substratum is replaced by new material, e.g. from construction] |
| |
Siltation |
A change in suspended sediment concentration of
100mg/1 outside the normal range experienced by the organism or community of interest for
1 year. |
| |
Desiccation |
A normally subtidal, demersal or pelagic species
including intertidal migratory or under surface species is continuously exposed to air and
sunshine for 1 hour. |
| |
Changes in emergence regime |
A 1 hour change in the time covered or not
covered by the sea for a period of 1 year. |
| |
Changes in water flow rate |
A change of two [MNCR] categories in water flow
rate for one year for 1 year. For example from moderately strong (1-3 knots) to very weak
(negligible). |
| |
Changes in temperature |
A change of 5 ° C
outside normal temperature range for 3 consecutive days. This definition includes short
term thermal discharges. A change in temperature of 2 ° C
outside normal temperature range for a year. This definition includes long term thermal
discharges.
For intertidal species, the normal range of temperatures includes the normal air
temperature regime for that species. |
| |
Changes in turbidity |
Exposed to 50 mg/l suspended particulate matter
or light absorption of 30% for five weeks. |
| |
Changes in wave exposure |
A change of two ranks on the [MNCR] wave exposure
scale e.g. from Exposed to Extremely exposed for a period of 1 year. |
| |
Noise |
Underwater noise levels 130 dB re 1 µPa (for
broad spectrum noise 45 – 7070 Hz) at 100 m from source intermittently over a 24 hour
period for 1 month during important feeding or breeding periods. This approximates to the
regular passing of a 30 m-trawler at 100 m or a working cutter-suction transfer dredge at
100 m. Atmospheric noise levels 98 dB re 1 µPa (for broad spectrum noise 45 – 7070
Hz) at 300 m below the source on and off over a twenty-four hour period for 1 month during
important feeding or breeding periods. This approximates to the regular passing of a
Boeing 737 passenger jet 300 m overhead. |
| |
Visual presence |
The continuous presence for one month of moving
objects not naturally found in the marine environment (e.g. boats, machinery, and humans)
within the visual envelope of the area in which the species under consideration occurs. |
| |
Synthetic compound contamination |
Environmental Assessment Level/Environmental quality Standard
(for seawater unless otherwise stated): |
Exposed to the following contaminant
concentration: |
| |
|
Tributyl tin: 0.002 m g/l (Maximum
Allowable Concentration) |
Long term: 0.004 m g/l
average in seawater for a 1 year period Short term: 1 m g/l
seawater for 2 days (48hrs) |
| |
|
DDT (all isomers): 0.025/l annual average |
Long term: 0.05 m g/l
average for 1 year Short term: 0.25 m g/l for 48hrs |
| |
|
Lindane (g -HCH): 0.02m g/l annual average. |
Long term: 0.04 m g/l
average in seawater for a 1 year period Short term: 0.2 m g/l
for 48hrs |
| |
Heavy metal contamination |
Environmental Assessment Level/Environmental quality Standard
(for seawater unless otherwise stated): |
Exposed to the following contaminant
concentration: |
| |
|
Copper: 5 m g/l annual average |
Long term: 10 m g/l
annual average for 1 year period. Short term: 50 m g/l for
48hrs |
| |
|
Mercury: 0.3 m g/l annual average
0.13 mg/kg for sediments |
Long term: 0.6m g/l
annual average for 1 year, or 0.26 mg/kg in sediments for 1 year Short term: 3 m g/l for 48hrs |
| |
Hydrocarbon contamination |
Environmental Assessment Level/Environmental quality Standard
(for seawater unless otherwise stated): |
Exposed to the following contaminant
concentration: |
| |
|
Benzo(a)pyrene: 88.8 m g/kg
sediment |
Exposed to 176 m g/kg
in sediment for 1 year. |
| |
Radionuclide contamination |
Exposure to concentration of radionuclide
equivalent to 100 mBg/l. of caesium-137 (137Cs) for 1 year. |
| |
Changes in nutrient levels |
A change of total nitrogen of 3 mg/l and/or
phosphorus of 0.3 mg/l as an annual average. Alternatively, a 50% increase of nutrients as
an annual average. |
| |
Changes in salinity |
A change of one category from the MNCR salinity
scale, e.g. from reduced to low for 1 year. A change of two categories from the MNCR
salinity scale, e.g. from full to reduced for 1 week. |
| |
Changes in de-oxygenation |
Exposure to dissolved oxygen concentration of 2
mg/l for 1 week. |
| |
Abrasion |
Force equivalent to a standard lobster pot or
creel landing on the organism. |
| |
Displacement |
Removal of the organism from the substratum and
displacement from its original position onto a suitable substratum. A single event is
assumed for assessment. |
| |
Introduction of microbial pathogens and parasites |
Sensitivity can only be assessed relative to a
known, named disease. Likely to cause partial loss of a population and will be assessed of
intermediate sensitivity. |
| |
Introduction of non-native species |
Sensitivity assessed against the likely effect of
the introduction of non-native species in Britain or Ireland. |
| |
Removal of target species |
Extraction removes 50% of the species from the
area under consideration. The habitat remains intact or recovers rapidly. |
| |
Removal of non-target species |
A species that is a required host or prey for the
species under consideration (and assuming that no alternative host exists) or a keystone
species in a biotope is removed. |
| Human activities |
|
* Activities which have been assigned a sensitivity score in
this report |
| |
Aquaculture |
|
| |
Aquaculture: algae |
|
| |
Aquaculture: fin-fish * |
|
| |
Aquaculture: shellfish |
|
| |
Climate change/global warming * |
|
| |
Coastal defence |
|
| |
Coastal defence: barrage |
|
| |
Coastal defence: beach nourishment * |
|
| |
Coastal defence: dredging * |
|
| |
Coastal defence: groynes |
|
| |
Coastal defence: sea walls/breakwaters * |
|
| |
Collecting (harvesting) |
|
| |
Collecting: algae (not kelp/wrack harvesting) |
|
| |
Collecting: bait digging * |
|
| |
Collecting: birds eggs |
|
| |
Collecting: curio |
|
| |
Collecting: higher plants |
|
| |
Collecting: kelp/wrack harvesting * |
|
| |
Collecting: peelers (boulder turning) * |
|
| |
Collecting: shellfish (winkles, mussels) * |
|
| |
Collecting: trade in wildlife |
|
| |
Development |
|
| |
Development (culverting lagoons) |
|
| |
Development: artificial reefs |
|
| |
Development: communication cables |
|
| |
Development: docks, ports & marinas * |
|
| |
Development: land claim * |
|
| |
Development: urban/industrial |
|
| |
Extraction (of resources) |
|
| |
Extraction: maerl * |
|
| |
Extraction: navigational/maintenance dredging * |
|
| |
Extraction: oil/gas |
|
| |
Extraction: rock/minerals (coastal quarrying) |
|
| |
Extraction: sand/gravel (aggregate dredging) * |
|
| |
Fishing |
|
| |
Fishing: angling * |
|
| |
Fishing: fixed netting (gill/tangle) |
|
| |
Fishing: mobile netting (seine) |
|
| |
Fishing: potting/creeling * |
|
| |
Fishing: suction/hydraulic dredging |
|
| |
Fishing: benthic trawling * |
|
| |
Fishing: pelagic trawling |
|
| |
Recreation |
|
| |
Recreation: diving/dive site |
|
| |
Recreation: marina |
|
| |
Recreation: popular beach/resort * |
|
| |
Recreation: water sports |
|
| |
Uses: archaeology |
|
| |
Uses: boats/shipping |
|
| |
Uses: boats/shipping (anchoring/mooring) * |
|
| |
Uses: boats/shipping (anti-fouling) * |
|
| |
Uses: boats/shipping (beaching/launching) |
|
| |
Uses: boats/shipping (oil spills) * |
|
| |
Uses: coastal forestry/farming * |
|
| |
Uses: education/interpretation |
|
| |
Uses: energy generation (wind/tide/wave) |
|
| |
Uses: freshwater extraction/storage on land |
|
| |
Uses: military |
|
| |
Uses: research |
|
| |
Waste |
|
| |
Waste: air (pollution) |
|
| |
Waste: cooling water (power stations) * |
|
| |
Waste: industrial effluent discharge * |
|
| |
Waste: land/riverine drainage (pollution) |
|
| |
Waste: litter and debris |
|
| |
Waste: nuclear effluent discharge |
|
| |
Waste: quarry waste dumping |
|
| |
Waste: sewage discharge * |
|
| |
Waste: spoil dumping * |
|
