Main Range Critical Zone Observatory


28° 13' 44.6016" S, 152° 25' 33.3516" E
Brief Site Description: 
The site is located in the Main Range National Park, within the Gondwana Rainforests remnant basalt volcanic landscape in eastern Australia.
Detailed Site Description: 

The site is located in the Main Range National Park, within the Gondwana Rainforests remnant basalt volcanic landscape in eastern Australia.

The site is located at an altitude of approximately 1100 m (varying from 950-1150 m across the site) and experiences a cool subtropical and subhumid climate with a sub-montane influence. Moist south-easterly winds blow on to the area for considerable periods of the year bringing appreciable rain (mean annual rainfall of 1350 mm), as well as low cloud and fog (of particular importance in meeting plant water needs). Winter air temperatures fall below zero, and light frosts are recorded in most years. Mean monthly maximum temperatures are around 30C in summer. The site is located in the upper headwaters of the Condamine River, and along with other headwater areas in the main range volcanics is an area of important runoff generation for this basin. At a more local level, the site sites on a drainage divide between the Emu Creek catchment to the north, and the Condamine River catchment to the south.

The site lies on the western slopes of the Tertiary basaltic lava flow that formed the Scenic Rim section of the Great Dividing Range (represented in purple in Figure 5). Basaltic lava was deposited over Mesozoic freshwater sediments (fine grained Walloon Coal Measures overlying coarse grained Marburg Formation). Sodosols, Dermosols, and Chromosols have developed from metamorphics and sedimentary parent rocks and alluvium on the western side of the Scenic Rim. Basalts have generally given rise to Vertosols on the western side of the divide and Dermosols on the eastern side, although patches of Ferrosols and Chromosols exist within the Main Range National Park. Brown Ferrosols are the dominant soil type at the CZO site.

The site hosts six major flora communities:

  1. Complex notophyll vine forest, dominated by Sloanea woollsii
  2. Araucarian notophyll vine forest, dominated by Araucaria cunninghamii
  3. Tall open forests, dominated by Eucalyptus andrewsii (New England blackbutt) with a grass and low shrub understorey
  4. Ecotonal communities, dominated by Eucalyptus grandis (flooded gum) and E. dunnii with an understorey of either rainforest species or sclerophyll forest species , the composition being determined by fire history
  5. Notophyll/microphyll vine forest with a predominance of Acmena smithii and Duboisia myoporoides in the canopy
  6. Tussock grasslands containing a mosaic of Themeda triandra (kangaroo grass) and Poa labillardieri (snow grass) tussocks interspersed with herbs, many of which have been introduced by grazing cattle in adjacent areas.

Within the site, there is a sharp ecotone (rainforest to eucalypt) and comparison plots to monitor the effects of logging on the rainforest were established in the 1960s. Vegetation dynamics in both the ecotone and the logged and unlogged plots have been mapped and monitored over time.  

PI: Talitha C Santini | PI: Joshua R Larsen | CO-PI: David Doley | CO-PI: Steven R Howell

Field Site Type: 
International affiliate
CZO Affiliate
Study Start Date: 
Mean Annual Precipitation: 
1 350 millimeters / year
Average Annual Temperature: 
Land Cover: 
Evergreen Forest
igneous-mafic extrusive
Soil Order: 
Hydrology: Name: 
Condamine River and Emu Creek catchments
Hydrology: Surface water stream order: 
First Order
Hydrology: Surface water - Stream Flow Performance: 
Hydrology: Groundwater: 
Arrangment of Aquifer Components - Complexly interbedded sequence of aquifers and confining beds
Group visibility: 
Public - accessible to all site users