Welcome to the METABARPARK Project website. The project aims to apply the new high throughput sequencing technologies to characterize benthic communities in the Spanish Marine National Parks using environmental DNA (metabarcoding). Our main objective is to characterize the hidden biodiversity which is usually overlooked by traditional methods. We will also try to assess the community impacts of invasive seaweeds.

Wednesday, January 20, 2016

Working with the data


We processed the samples, extracted the DNA and amplified the barcoding genes for the second sampling (2015) performed at each site. We received the sequences in November (for the COI gene) and December (for the 18S gene). So we have now all genetic data of the samplings done in 2014 and 2015 in Cíes Islands and the Cabrera Archipelago.

In the last months we have been busy working with the bioinformatic analyses of such a huge amount of data. We had to adapt and improve existing pipelines, write code ourselves, and check different approaches at each step of the process.

Now we are drafting our first manuscript for publication with the results of the first samplings with biodiversity assessment and community comparisons within and between the Parks. We have also assembled a large dataset with all sequences obtained in 2014 and 2015 that is currently being analysed to assess temporal changes in the community structure in both Parks. We hope to come up with interesting results soon!


Master Thesis with Metabarpark results


In November, 2015, Manuel Orobitg, student of the Master of Oceanography and Management of the Marine Environment at the University of Barcelona, presented his MSc Thesis “Morphology vs metabarcoding. A comparison of techniques for biodiversity assessment in Maërl beds”, supervised by Xavier Turon, Creu Palacin and Owen Wangensteen.




Image of the sampling of the Maërl community in Islas Cíes
In this study, Manuel analysed morphologically samples collected at the same time as the ones for the genetic studies in the detritic bottoms of Islas Cies and Cabrera Archipelago. He focused his analyses on three major groups: polychaetes, arthropods, and molluscs. He identified at the lowest level possible, with the help of taxonomists (a big thanks goes to Daniel Martin and Lídia Delgado), the species present in the 10 and 1 mm filtrates, and obtained biomass values by weight. The morphological analyses found 77, 45, and 44 morphospecies of polychaetes, crustaceans, and molluscs, respectively, while the genetic technique yielded 182, 245, and 70 MOTUs, respectively, for the same size fractions. Thus, metabarcoding allowed the determination of a higher diversity, but the taxonomic precision attained was higher with morphology. On the other hand, all structural parameters (biomass dominance curves, alpha- and beta-diversity patterns) were markedly different between the metabarcoding and the morphology datasets, indicating that both methods capture different aspects of the biodiversity structure present. The morphological datasets tended to be quantitatively dominated by a few species, while metabarcoding detected a more even distribution of biomass of the dominant MOTUs.

Assortment of arthropods from the 1 mm fraction