Associate Professor Burkitt provided expert guidance to Upper Moawhango Catchment Group, enhancing their understanding of dissolved reactive phosphorus levels, and identifying potential sources of the elevated concentrations in Upper Moawhango Catchment streams – particularly the Waikakahi sub-catchment.
Upper Moawhango Catchment Group (Rangitikei Rivers Catchment Collective)
Associate Professor Lucy Burkitt (Massey University)
After reviewing the water quality data collected by the group’s own monitoring, and site visits with the support of A2E, it was discovered that the source of phosphorus is likely linked to natural geological processes. This is because the high concentrations occur primarily during base or low flow conditions.
Although it is important to implement management measures to reduce phosphorus loss, it was identified that this alone may not sufficiently address the exceptionally high concentrations of dissolved reactive phosphorus (DRP) currently observed in the Waikakahi catchment.
Being a complex issue that requires further investigation, existing literature and previous work from Horizons Regional Council was built on; and it was recognised that the potential effect of geology on DRP levels in streams and rivers in the area should be considered for this catchment.
Recommendations from the work include conducting detailed research to confirm if the high DRP levels are caused by geological factors in collaboration with Horizons Regional Council.
As a result of this initial case being raised by the catchment group, Massey University and Horizons Regional Council have subsequently met to discuss possible future support from the University’s research group as a potential future focus. This research could involve taking further water samples and monitoring of groundwater wells that could be installed at key locations.