

Pressures affecting the Antarctic terrestrial environment
Pressures affecting the Antarctic terrestrial environment
Populations of some native plants are expanding rapidly on subantarctic islands where ice-free areas are increasing. Composition of plant assemblages may change as non-native species become established
At the Antarctic Peninsula, populations of two native flowering plants are expanding rapidly; similar observations have been made on subantarctic islands where ice-free areas are increasing; composition of plant assemblages may change
In some areas of East Antarctica, there is evidence of long-term drying, and moss beds appear to have contracted to areas with reliable water supply
In East Antarctica, mosses are drying out rapidly due to ice melt and channel run-off away from existing moss beds
In East Antarctica, moss growth is retarded because of changes in wind patterns related to ozone depletion
Introduction of non-native species and pathogens
This assessment summary component has changed from 2011.
The term 'alien species' has been replaced with 'non-native species'.
The original 2011 summary, grade, trend and confidence levels have been replicated here to assist comparison of changes between reporting cycles.
Invasive species can have a devastating effect on endemic species and communities. Poa annua, a small grass, is spreading and outcompetes native plant species. The eradication program of cats, rabbits, rats and mice at Macquarie Island has been completed successfully and has had a positive effect on plant communities (see State and trends of the Antarctic environment)
Further warming of the atmosphere may help pathogens and non-native species to become established
Invasive species can have a devastating effect on endemic species and communities. The eradication program currently under way at Macquarie Island will have a positive effect on seabird populations Further warming of the atmosphere may help pathogens to become established
More ice-free areas are likely to suffer from erosion, especially on subantarctic islands
More ice-free areas are likely to suffer from erosion, especially on subantarctic islands
Deposition of solid and liquid wastes can affect both terrestrial and marine communities
Impacts tend to be localised, but pollutants also come from nonlocal sources and are likely to contaminate much larger regions
Deposition of solid and liquid wastes can impact both terrestrial and marine communities. Impacts tend to be localised, but pollutants are also received from non-local sources and are likely to contaminate much larger regions
Deposition of marine debris, particularly plastics, can lead to ingestion by, and entanglement of, seabirds and seals. Negative impacts on chicks are also possible, because ingested debris may leach harmful chemicals
Increased visitation puts pressure on wildlife populations. With increasing demands to see wildlife, more areas may be visited more often and by more people. More research activities may also increase wildlife disturbance. New technology such as drones may disturb wildlife
Increased visitation puts pressure on wildlife populations; with increasing demands to see wildlife, more areas may be visited more frequently and in greater numbers
Many human activities significantly alter the natural environment. Visitation can negatively affect habitat—for example, through trampling
Many human activities significantly alter the natural environment (e.g. stations); visitation can negatively affect habitat through trampling
Assessment Summary Key
Grades
Very low impact
There are few short-term, reversible impacts from this factor
Low impact
There are transitory impacts from this factor, but they are locally restricted
High impact
There are significant impacts from this factor (may be cumulative); impacts are region specific and may become irreversible in future
Very high impact
There are predicted significant impacts from this factor that are irreversible; impact is region specific
Recent Trends
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Improving
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Stable
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Deteriorating
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Unclear
Confidence
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Adequate: Adequate high-quality evidence and high level of consensus
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Somewhat adequate: Adequate high-quality evidence or high level of consensus
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Limited: Limited evidence or limited consensus
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Very limited: Limited evidence and limited consensus
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Low: Evidence and consensus too low to make an assessment
Comparability
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Comparable: Grade and trend are comparable to the previous assessment
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Somewhat comparable: Grade and trend are somewhat comparable to the previous assessment
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Not comparable: Grade and trend are not comparable to the previous assessment
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Not previously assessed
Comments
Assessment remains the same as in 2011.