Research Report 2
Hart BT & McGregor RJ
Supervising Scientist, 1982
ISBN 0 644 01234 X
About the report
A six-week survey of the physico-chemical limnology of eight billabongs in the Magela Creek catchment of the Northern Territory was conducted between December 1977 and January 1978. This covered the important period corresponding to the end of the dry season and the commencement of the wet season. Each billabong was sampled approximately weekly.
At the end of the dry season, the billabong waters had elevated conductivity and turbidity, and generally higher sodium,. potassium, chloride, phosphate, nitrate and chlorophyll a concentrations. They were generally slightly acidic and, in some, the bottom water was anaerobic.
With the commencement of the wet season, the billabongs were flushed and a significant improvement in water quality was noted. Temperature, dissolved oxygen and redox potential data were used to classify these billabongs tentatively as polymictic. Under certain circumstances mixing did not occur for several days, during which time the bottom waters became significantly depleted in dissolved oxygen. From the limited nutrient and chlorophyll a data available, it would appear that the billabongs at the end of the dry season are mesotrophic.