Lake Sediment Analysis - Rotorua
PTC Trust was privileged to partner with Lake380 team leaders Marcus Vandergoes -Project leader GNS science, Susie Wood - Project leader Cawthron Institute and John John Pearman in offering young Rotorua girls the opportunity to conduct some lake sediment analysis. The scientists within Lake380 have a 5year mission to characterise the health of 10% of all of NZ lakes (380 of them).
The process involves analysing core sediments extracted from the lake using a range of techniques in order to determine historical changes in water quality, aquatic life and even landscape over 1000years.
As part of their more extensive Rotorua Lakes fieldwork, the Lake380 team conducted analyses across Lake Tarawera, Lake Rotoiti, Lake Okaro, Lake Rotorua and Rotoehu . Our Rotorua students got the opportunity to experience the process at Waiteti Bay in Ngongotaha.
Dr Woods demonstrated to the youths how to utilise plankton nets to collect phytoplankton samples. These nets concentrate the algae and organisms in the water allowing biodiversity assessment to be undertaken.
Dr Vandergoes outlined to the girls the method of using sediment corers to recover cores from lakes. Some of the many samples extracted at the Rotorua lakes were shown to the students. Our group was amazed to see a distinctive section of grey ash that Lake380 scientists believes occurred from Mount Tarawera eruption in 1886.
Dr Pearman taught our rangatahi how environmental DNA can be utilised within a lake environment. Youth then conducted their own DNZ extraction and precipitation process - which was quite fascinating and enlightening.
Diligence at work
Youth were enthused and motivated as they appropriated some high level methodologies to analysing their lakes. It is critical that the next generation is empowered to restore our lakes. Health warnings have been issued in 2018 for the presence of blooms of potentially toxic blue-green algae in Lake Okaro and Lake Rotoehu. Ensuring our youth are aware of the warning signs enables them to assist whanau in making wise and sustainable future choices.