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Map of the Warra LTER site and adjoining areas, showing the location of the four altitudinal transects and their associated baseline altitudinal monitoring and ecotonal plots. |
Image: Forestry Tasmania |
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Project summary:
This is the invertebrate-monitoring component of the FT icon project: Mount Weld Altitudinal Transect Ecotonal and Baseline Altitudinal Monitoring Plots (BAMPs), which is itself a long term ecological research program monitoring distributional change in vegetation and fauna along an altitudinal gradient on Mount Weld. This project is registered as a Satellite Project for the International Biodiversity Observation Year (IBOY).
Despite its current preliminary nature, the invertebrate data displays clear altitudinal and seasonal patterns. The tree line and the 700-1000m zone appear to be notable in terms of invertebrate distribution. While the composition of ground-based taxa may be closely related to the composition of the vegetation (or its drivers), the airborne invertebrate fauna may be more closely related to structural characteristics than the vegetation per se. Of all invertebrate taxa, the Coleoptera appear to be the best potential indicators across most altitudes and times.
These baseline data will be available for comparison with data collected in future decades and as such may provide interesting information in the advent of significant climate change, particularly its effects on the higher altitude zones.
Methodology: Invertebrate sampling was by a combination of pitfall traps and malaise traps. Sampling was organised and primarily undertaken by DPIWE (Niall Doran and Michael Driessen). Due to funding constraints, only two transects with the little disturbance history but great altitudinal range were used. Samples were collected over two consecutive summers: February- April 2001 and November 2001-April 2002. Collection and re-setting of traps was nominally based on a four-week cycle
Six pitfall traps were established at each plot, with the exception of the 500 m site on one of the transects. Traps were arranged in a regular pattern in each grid, but with exact pitfall trap location dependant on the availability of sufficiently deep substrate in which to set it. Standard pitfall traps consisted of a 15cm length sleeve of 9cm diameter PVC stormwater pipe sunk vertically into augered holes in the soil. (At the 100 m site, soil was insufficiently deep and soil and rock needed to be built up around the PVC sleeve). A 425 ml plastic cup of matching diameter was fitted within each sleeve. To prevent rain and debris entering the cups directly, plastic food container lids were supported 3 cm above the cups on bamboo skewers. Each cup was filled with 100 ml of either 33% ethylene glycol for sheltered sites (below the tree line: 100 m 1000 m) or undiluted ethylene glycol for exposed sites (above the tree line: 1100 m 1300 m). In the last two months of the study, 5% glycerine/glycerol was added to the pitfall mix to improve the condition of specimens recovered for identification. Pitfall traps were cleared by filtering the ethylene glycol through a 0.9×0.3 mm mesh, and resuspending the mesh in 70 % alcohol. Pitfalls were then recharged with fresh ethylene glycol. All waste ethylene glycol and alcohol was removed from the sites. Upon completion of the pitfall trap sampling programme, plastic cups were removed but the PVC sleeves were left in place, to aid relocation of trapping sites in future sampling programmes.
The delicate nature of malaise traps made them unsuitable for use in the exposed conditions above the tree line (1100 m-1300 m). A single trap was installed at 100 m, 200 m, and 400 m on one transect, and at 600 m, 800 m and 1000 m on the other. The standard design of Malaise trap was used as elsewhere in Warra, composed of a 28-gauge Terylene mesh tent with dark central panels and a light-coloured sloping roof, leading to a collection bottle containing 70% ethanol. The trap was placed roughly at the centre of the grid, but the precise location was dependent on finding suitable trees to which they could be attached while maintaining an open flight path for insects approaching the trap. Malaise traps were cleared and reset by simply replacing the collecting bottle with a new one. Upon completion of the Malaise trap sampling programme, the traps were completely removed.
Datasets: None available.
Publications: Doran, N.E., Balmer, J., Driessen, M., Bashford, R., Grove, S., Richardson, A.M.M., Griggs, J. & Ziegeler, D. (2003). Moving with the times: baseline data to gauge future shifts in vegetation and invertebrate altitudinal assemblages due to environmental change. Organisms, Diversity and Evolution 3(2): 127-149.
Forster, L. & Grove, S.J. (2008). The beetles (Coleoptera) of the Warra Mount Weld Altitudinal Transect Ecotonal and Baseline Altitudinal Monitoring Plots (BAMPs) Forestry Tasmania, Hobart.
Grove, S.J. (2004). Warra – Mount Weld altitudinal transect ecotonal and baseline altitudinal monitoring plots (BAMPs): establishment report. Technical Report no 17/2004. Forestry Tasmania, Hobart.
Mesibov, R.E. (2009). A new millipede genus and a new species of Asphalidesmus Silvestri, 1910 (Diplopoda, Polydesmida, Dalodesmidea) from southern Tasmania, Australia. Zookeys 7: 55-74
Palmer, C.M., Trueman, J.W.H. & Yeates, D.K. (2007). Systematics of the Apteropanorpidae (Insecta: Mecoptera) based on morphological and molecular evidence. Invertebrate Systematics 21: 589-612.
Powledge, F. (2002). A look back at the International Biodiversity Observation Year. BioScience 52: 1070-1079.
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