TS-CRC Student project - Aspects of tropical heathland ecology - Floristics and patterning of vegetation communities at Cape Flattery, north Queensland

James Cook University, Townsville

Nicholas Cuff

Tropical heathland assemblages have been identified as a unique feature of Cape York Peninsula. However, as with many of the vegetation assemblages in this area, little is known of their ecology. Such systems have developed primarily on large, siliceous sand dunes close to the coast. One such extensive heathland mosaic has developed between Capes Bedford and Flattery, on the eastern side of Cape York.

This complex contains a number of recognisable vegetation communities in close proximity to one another upon single dune units, providing a simple and convenient situation in which the nature of such vegetation pattern can be evaluated. My project aims to assess the floristic and environmental differences that exist between a number of these interrelated vegetation units. These include exposed dwarf heath; sheltered dry heath; wet heath and woodland/evergreen notophyll vine thicket.

Vegetation composition and structural data has been collected from each of these communities and is in the process of being analysed. It appears that distinct floristic differences exist between the heath and forest elements, whilst structural differences appear to be more significant in separating the heathland elements of the flora.

Collection of environmental data, including soil samples for physical and chemical analysis and weather data from automatic climate monitoring stations aims to identify environmental correlates most strongly related to the observed vegetation patterns in the area. It is hypothesised that patterns will most strongly correlate with the nature of prevailing winds in the area and chemical properties of the soil associated with periods of seasonal waterlogging.

The outcomes of this investigation are seen as twofold. Firstly, the detailed study of the vegetation assemblages in this area will provide useful insights into the ecological function of this little known tropical vegetation assemblage. Detailed studies of subtropical and temperate Australian heathlands have identified specific parameters that appear to control vegetation patterning in these systems. It will be interesting to see if similar processes operate in a tropical setting. Secondly, the Cape Flattery area has been the subject of a sand-mining lease for the past 30 years.

Rehabilitation of mined areas has to date been somewhat hindered by the lack of detailed knowledge of this heathland system. Cape Flattery Silica Mines Pty Ltd has expressed an interest in my research, as it will need baseline data and an understanding of the area's ecology to meet its rehabilitation objectives. I hope that my work will provide Cape Flattery Silica Mines with information to allow the more efficient and effective rehabilitation of this unique area.

Supervisors:

A/Prof Betsy Jackes, JCU
A/Prof Ross Hynes, CRC/JCU
A/Prof Ross Coventry, JCU