Indicator 70 - The presence or absence of vascular plant species in two defined areas of Heard IslandIndex - Description | Custodian evaluation | Related resources | Parameters |
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| Indicator Definition | The presence/absence of vascular plants species in specified northern and eastern regions of Heard Island. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Responsible Organisation |
 Australian Antarctic Division (details) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Custodians |
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| Theme Area | Biodiversity | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Indicator Type | Condition | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Criteria the Indicator Satisfies |
The following 11 out of 15 criteria
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| Date Input | Yearly measurements | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Monitoring Location |
Heard Island (details)
Geographic Coverage is
Longitude (73.3588 to 73.4197)
Latitude (-53.1522 to -53.0494)
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| Rationale For Indicator Selection | Heard Island arguably is one of the most rapidly changing environments for vegetation in the sub-Antarctic region, due to its extensive and rapid glacial retreat. This retreat has been accelerated by rising regional temperatures which have been reported across the Southern Ocean islands; (see Bergstrom and Chown 1999, Frenot et al. 1997). Between 1947 and 2000 approximately 36 km2 of new terrain (including several large lagoons) has been exposed by ice retreat, representing nearly 10% of the total area of the island (Ruddell, in prep). New land and ameliorating conditions presents opportunity for colonization by plants and there are three likely sources from which propagules of plants (eg seeds and fruits) can arise: local vegetation; long distance dispersal, particularly on migratory birds and blown in from low altitude storms; dispersal by humans. In addition, Heard Island possesses the smallest vascular plant flora of any major sub-Antarctic island (11 species so far recorded). Many species on the island including the major plant species (Azorella selago) are 'tolerator' species and poor competitors (Bergstrom and Selkirk 2000). The consequence of this is that not only are there opportunities to colonise new areas on Heard Is there are also opportunities for more aggressive species to invade already vegetated areas. This indicator monitors newly arrived species and the expansion of already established species in defined ice-free regions on Heard Island. It is a measure of how vegetation is responding to changed environmental conditions. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Design and Strategy For Indicator Monitoring Program | Spatial scale: Northern and eastern survey areas on Heard Island. North region [Bounding Rectangle: NW corner- lat(52deg 59min 51sec), long(73deg 21min 32sec). SE corner- lat(53deg 3min 32sec), long(73deg 25min 11sec)] - encompassing Azorella Peninsula, Corinthinan Bay, Mt Drygalski, Pageos Moraine, Mt Andre and Mt Aubert de La Rue. East region [Bounding Rectangle: NW corner- lat(53deg 2min 58sec), long(73deg 38min 18sec). SE corner- lat(53deg 9min 8sec), long(73deg 44min 18sec)]- bounded by Winston Lagoon in the south and Compton Lagoon to the west and including Paddick Valley, Dover Moraine, Skua Beach and Fairchilds Beach. Frequency: Ground surveys of the selected areas will be conducted every three years. Measurement technique: Surveys will be restricted to below 200 m in altitude. Time to survey the defined areas is approximately 7 days for the eastern region and 4 days for the northern region (weather permitting). Species richness and composition will be compared with other sub-Antarctic islands (see Chown et al. 1998) using the RiSCC database. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Research Issues | In the long term, data should be linked with more detailed mapping of: Vegetated areas vs non-vegetated areas either by aerial photography or remote sensing using synthetic aperture radar; Species that are demonstrating rapid change (eg Azorella selago, Poa annua and Acaena magellanica). This data will provide information on the response of plant species to climate change. Analysis of detailed vegetation maps will establish how each species is affected and may aid in determining the lag between climate change and vegetation response. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Data |
Data prepared by J Scott and D. M. Bergstrom Nov 2001 Status November 2000
Codes used in table Xw - Species present, widespread Xl - Species present, localised a - Suitable habitat apparently present b - Unlikely that suitable habitat is present c - Don't know * Effort expended on surveys: 1 - Reasonably thorough 2 - Incomplete 3 - No surveys done | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Data Quality, Interpretation and Analysis of Indicator Data |
Vascular plant species diversity for an Eastern location and a Northern location on Heard Island are calculated using data acquired from surveys determining the presence or absence of eleven vascular plant species in these regions. The areas selected include a mixture of older deglaciated areas (greater than 2000 years) and newly deglaciated areas. Increase in species richness within a region could mean either expansion of the current intra-island distribution, a new arrival or an introduction by humans. Reduction in vascular species richness may be due to destruction of biota or habitat by human or animal activities, or changes in climatic regimes reducing the range of a species. Selected sites will be monitored temporally. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Data Distribution |
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| Data Access Constraints | Data for this project are not yet publicly available. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Custodian Evaluation |
For definitions of the Scale categories, consult the Explanation of the Status Categories | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Related resources |
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| Parameters |
The properties link can be used to view details of the parameters measured for this indicator.
Parameters - | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
