Benson & Fallding, Brisbane Water National Park 
99 
upstream. Mangroves play an essential role in estuarine ecosystems and are parti¬ 
cularly important to both oyster and fish populations which are harvested com¬ 
mercially. Their conservation and protection is important. Reedland/rushland 
with Casuarina glauca (Community 11) occurs only in small isolated areas along 
Mooney Mooney, Mullet and Patonga Creeks. The only saltmarsh located during 
the survey consisted of two areas on Patonga Creek; the larger of these was being 
destroyed by trail bikes. None of the estuarine-associated plant communities are 
at present protected by conservation legislation. 
Fire 
During the preparation of the vegetation map some relationships were found 
between fire history and structural formation, species composition and the distri¬ 
bution of some rare species. For example, closed to open-scrub (Community 8) 
with regular burning appears to become dominated by the seed-regenerating species 
Banksict ericifolia and Hdikea teretifolia. These species are killed by fire and re¬ 
generate from seed. However Banksia ericifolia , in particular, takes five years to 
flower and plants do not carry heavy seed loads until they are 8 to 10 years of age 
(Recher 1980). Maintenance of this community therefore requires a period between 
burning of at least 8 to 10 years but less than about 25 years. 
The minimum period between fires is probably important for many species. A 
number of the rare species, for example, Darwinia procera, Leucopogon amplexicauHs, 
L. margarodes and Boronia anemonifolia, were found in areas which had not been 
burnt for at least eight years. There is much debate on the proper use of fire as a 
management tool in natural areas. Only when sufficient biological information on 
communities and species is available can scientifically based conclusions be drawn. 
For many other aspects of management, further information is required on the 
biology and life histories of individual species and the inter-relationships between 
them. Monitoring of change over time within and between plant communities 
could be carried out in a number of ways, including permanent quadrats set out on 
a grid or random basis, colour oblique or low level aerial photography regularly 
taken over selected sites, or a combination of both quadrats and photography. 
ACKNOWLEDGMENTS 
We wish to thank R. G. Coveny and the botanists of the National Herbarium 
of New South Wales for help with identification of plant specimens; B. Vile and 
staff of the National Parks and Wildlife Service for information on aspects of Brisbane 
Water National Park; J. M. Powell, D. H. Benson and members of the technical 
staff of the National Herbarium, particularly E. Bie, for assistance with the maps, 
diagrams and tables. 
REFERENCES 
Bureau of Meteorology (1979). Climatic Survey Sydney, Region 5, New South 
Wales. Department of Science and the Environment, Canberra. 
Cameron, D. V. (1974). Vegetation map and herbarium of Old Warrah Sanctuary, 
Brisbane Water National Park. Unpub. B.Sc. (Hons.) thesis, University of 
Sydney, Sydney. 
Clarke, L. D. & Hannon, N. J. (1970). The mangrove swamp and saltmarsh com¬ 
munities of the Sydney District. J. Ecol. 58, 351-369. 
Coveny, R. G. (1968-1978). Species lists for Girrakool and Wondabyne, Brisbane 
Water National Park. (Unpub.). 
Hartley, W. & Leigh, J. (1979). Plants at Risk. Australian National Parks and 
Wildlife Service, Occasional Paper No. 3. Canberra. 
