Marine planktonic biodiversity monitoring an assessment of ecosystem health status through high-throughput sequencing

Abstract

Here, we explore the usefulness of high-throughput sequencing technologies (HTS) as a tool for marine biodiversity monitoring and assessment of ecosystem health status. Whereas 454-pyrosequencing of 16S and 18S rRNA gene amplicons (454tags) has widely been used, only few studies have used Illumina (itags) and HTS cross-platform studies are rare. We have performed a comparison of the performance of 454tags and itags on a set of samples collected in the NW Mediterranean to determine bacterio- and picoplankton biodiversity. Preliminary results show that, due to the increase in the length of sequence reads, itags offer similar classification efficiencies than 454tags at a much lower cost, being therefore a cost efficient approach for marine biodiversity monitoring. We have also explored the concept of ‘indicator species’ and tested it in our samples, which include data from highly human-impacted beach areas to the open ocean. Our results show that certain taxa (i.e. some Gammaproteobacteria or the SAR11 clade) as well as the ratio between some phylogenetic groups (i.e. Gammaproteobacteria/Alphaproteobacteria) may be good indicators of ecosystem health status