Characterising swamp biodiversity and community structure with environmental DNA

In the coastal highlands of the Sydney Basin, Australia, upland swamps are a characteristic environment that supports a unique diversity of biota. These ecosystems carry out essential services including hydrological functions and carbon sequestration. They are currently listed as endangered ecosystems under the Threatened Species Conservation Act 1995, with some of the main threats including mining practices and urbanisation. Previous research on these environments have focused on their geomorphological and hydrological features, with little research on the interactions between local environmental factors and species diversity across spatial scales. This thesis used environmental DNA and metabarcoding techniques to characterise prokaryotic and eukaryotic components of biodiversity across three distinct swamp regions; the Blue Mountains, Upper Nepean State Conservation Area and Budderoo National Park. The relationship between these communities and environmental variables was investigated, as well as their diversity and composition across local and regional scales. Our results indicated that prokaryotic communities were shaped by local environmental variables to a greater extent compared to eukaryotic communities, which were more influenced by geographic distance. This research provides an insight into the uniqueness of swamp biodiversity across multiple spatial scales whilst also demonstrating a novel approach for the future monitoring of swamp ecosystems -- abstract.