Are groundwater inputs driving de-oxygenation, acidification, and eutrophication in northern NSW rivers and estuaries?
A project undertaken at the Centre for Coastal Biogeochemistry, Southern Cross University and supervised by Isaac Santos
A number of East Australian estuaries are severely and recurrently impacted by de-oxygenation, acidification, and eutrophication. These issues may cause total fish mortality and have a major regional economic impact. Increasing nutrient inputs from agriculture and urban activities leads to harmful algal blooms and a reduction in aquatic biodiversity.
Our project revealed a strong link between groundwater discharge and surface water quality in the Richmond River Estuary.
The following 4 scientific papers have been have been published:
Santos, I.R., de Weys, J., Tait, D.; Eyre, B.D. 2013. The contribution of groundwater discharge to nutrient exports from a coastal catchment: Post flood seepage increases estuarine N:P ratios. Estuaries and Coasts, in press.
Santos, I.R., de Weys, J., Eyre, B.D., 2011. Groundwater or Floodwater? Assessing the Pathways of Metal Exports from a Coastal Acid Sulfate Soil Catchment. Environmental Science & Technology 45, 9641-9648.
Santos, I.R.; Eyre, B.D. 2011. Radon tracing of groundwater discharge into an Australian estuary surrounded by coastal acid sulphate soils. Journal of Hydrology, 396: 246-257.
de Weys, J.; Santos, I.R.; Eyre, B.D. 2011. Linking groundwater discharge to severe estuarine acidification during a flood in a modified wetland. Environmental Science & Technology, 45 (8), 3310-3316.
The following Honours theses have been supported at least in part by this project:
de Weys, J. 2010. The contribution of groundwater discharge to estuarine acidification during a flood (Tuckean Swamp, northern NSW). Honours Thesis. School of Environmental Science and Management, SCU, Lismore, NSW, 67 p.
Gleeson, J. Submarine groundwater discharge and its biogeochemical implications in disturbed and natural estuarine systems. Honours Thesis. School of Environmental Science and Management, SCU, Lismore, NSW, 54 p.
Makings, U. Using radon to determine whether groundwater is a major source of nutrients to a subtropical tidal river and estuary. Honours Thesis. School of Environmental Science and Management, SCU, Lismore, NSW, 54 p.
Atkins, M. 2012. Groundwater discharge as a significant source of carbon dioxide to a coastal floodplain creek. Honours Thesis. School of Environmental Science and Management, SCU, Lismore, NSW, 80 p.
The thesis by de Weys has been turned into a scientific journal article. The other 3 theses above are available under request and will be prepared for publication in a scientific journal.