From the 1st to the 10th of February a small barefoot team consisting of Phd candidate Michael reading, IP student Kylie Maguire, Douglas Tait and Dirk Erler travelled to Rarotonga in the Cook Islands to investigate groundwater contribution to nutrient budgets and greenhouse gas emissions. The Lagoon has extensive eutrophication issues and as a result a coral to macro algae dominated phase shift is evident. The research will be used to identify potential mitigation measures as part of a larger international collaboration including both industry and other universities.
The team conducted time series sampling, spatial surveys and sediment incubations in the lagoon in addition to sampling creek surface water and groundwater at a range of monitoring wells adjacent to the lagoon. Radon and Radium isotopes were measured to quantify pore water exchange, fresh groundwater seepage and water residence time in the lagoon. Physiochemical parameters, nutrient and greenhouse gas levels were also measured in ground and surface waters and denitrification rates were measured in sediment using closed incubation chambers.
Overall, a lot of fun was had over the 8 massive days (and nights) in the field. All objectives were met despite some equipment issues (que the sinking kayak) and local tv and newspaper interviews.