Are Harmful algal blooms (HABs) migrating north?

In this working package we will use metabarcoding of the 18S region to observe the presence of HAB-forming phytoplanktonic microalgae in a) transects from Disko Island and b) along the Greenland West Coast. Community distances will be computed as a community-level estimate of connectivity, also separately for potentially harmful and non-harmful subsets of phytoplankton taxa.

Where do the microalgae come from?

We will use transcriptomics to investigate species distribution patterns. Using data shared with other work packages, we aim to characterize representative taxa comparing different samples across sampling campaigns and sampling sites. The aim is to observe the three-dimensional distribution of the potential HABs, as well as confirming temporal variability thereof. Transcript sequences for target species across all locations will be extracted, aligned against a de novo reference bases on consensus across locations, and genotyped for quantification of population differentiation in the context of geographical and environmental distances.

At first, the existing literature will be scouted for trends in spatial variability and will result in a review.

Three sampling campaigns will be undertaken within the consortium: two expeditions based on Disko Island in summer and spring, and a ship cruise to monitor the western coast of Greenland. All samples of microalgae will be partitioned into three fractions: microplankton (>20µm), nanoplankton (>3µm) and picoplankton (>0.2µm) to ensure comparability with previous studies (Elferink, Bruhn). Different depths will also be taken to observe differences in depth distribution, as well as along the transect.