Dr John Pearman1, Mr Jack Sissons, Dr Joseph Kanyi Kihika, Ms Jessica Schnattschneider, Ms Mckayla Holloway, Dr Susie Wood
1Cawthron Institute, Nelson, New Zealand
Biography:
John Pearman is a molecular ecologist with experience working in aquatic environments. The completed his PhD at the University of Warwick, UK focusing on the spatial diversity and transcriptomics of photosynthetic picoeukaryotes in the Atlantic Ocean. After this, he undertook postdoctoral work at King Abdullah University of Science and Technology (KAUST) investigating the ecology of Red Sea organisms using molecular approaches. This involved using metabarcoding of environmental samples from a range of organisms, from planktonic bacteria to coral reef invertebrates, and habitats encompassing oligotrophic surface waters, to marine sediments and coral reefs. He has also utilised ‘omic’ methodologies and nutrient enrichments of mesocosms to understand how the diversity and function of microbial planktonic communities are affected by eutrophication of coastal waters. More recently he has moved to the Cawthron Institute, New Zealand and focussed on freshwater systems. This research has focussed on investigating the contemporary and historical changes in lake communities by combining molecular methodologies with a suite of other analytical methodologies.
Abstract:
Lakes in Aotearoa-New Zealand are under unprecedented pressure. Traditionally, monitoring efforts have mainly focused on assessing the magnitude of eutrophication which shows that many of the lakes are in a degraded state. Lakes though are impacted by a variety of other stressors such as antibiotics, heavy metals and pesticides. Novel methods are required for an improved understanding of what stressors are impacting lakes. In this study, to understand the metabolic functioning of Aotearoa-New Zealand’s lakes and identify genes linked to stressors we have undertaken metagenomic sequencing of surface sediments from over 150 lakes spread across the country. These lakes range from lowland lakes with highly modified catchments to alpine lakes with native vegetation in the catchment and include a variety of stressor gradients. We have constructed a gene catalogue representative of the metabolic functions being undertaken in lakes across Aotearoa-New Zealand. Comparison of the abundance of genes with associated lake environmental data has been used to identify indicative genes for the multitude of stressors that impact lakes. This study has enabled a better understanding of the metabolic functions occurring within lakes and has identified genes that were indicative of a variety of stressors affecting lakes in Aotearoa-New Zealand. This more holistic view of the stressors which are impacting lakes can guide lake management in the rejuvenation of the lakes of Aotearoa-New Zealand.