Project Details
Projekt
Pole to Pole exchange: Climate facilitated cyanobacterial parasite pressure & mat ecosystem response
Applicant
Professor Dr. Daniel Reto Dietrich
Subject Area
Oceanography
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 462700468
Previous research of our group comparing the cyanobacterial mat species diversity from the Arctic with those of the Antarctic Peninsula demonstrated a high species overlap (Kleinteich et al. 2017). As serendipitous simultaneous development of these cyanobacterial species appears unlikely, it is assumed that cyanobacteria are transported from the Arctic to the Antarctic via birds or aerosols. This project investigates the possible exchange of cyanobacteria, cyanobacteria parasitic fungi and viruses and the impact of climate change on the potential establishment of more temperate tolerant cyanobacteria and their parasites endemic to the Arctic (microbial xeno-species) in Antarctica, thereby changing the Antarctic cyanobacterial mat communities. Our findings (Kleinteich et al. 2012) showed a change in species diversity and cyanobacterial toxin production upon exposure of Antarctic cyanobacterial mats to increased temperatures. This project has four major objectives: 1.) to determine whether old (Scotts expedition 1902) cyanobacterial mats and more recent cyanobacterial mats from McMurdo, Byers and Rothera (1990, 1999/2000, 2010, 2021/2022) show a distinct time-scale dependent presence of Arctic microbial xeno-species (Historical descriptive study); 2.) to compare cyanobacteria, and their parasitic fungi and viruses, found in Arctic locations (Svalbard) to locations in the Antarctic Peninsula; 3.) to determine whether temperature increase in situ (Rothera and Byers) via plexiglas covers for 21 days will provide for cyanobacterial diversity change, increased fungal and viral parasitism, and toxin production, and 4.) whether the in situ experiments can be replicated in the laboratory cold rooms with cyanobacterial mats with/without additional exposure to fungi and viruses from Arctic cyanobacterial mats and/or increased temperatures (Mechanistic studies). Cyanobacterial mat diversity, fungal and viral presence will be determined using Illumina (16S, ITS and G20 genes) and shotgun sequencing. Fungal and viral abundance will be determined using ddPCR, while monitoring and comparison of cyanotoxin content will be carried out via PCR, ELISA and UPLC-MS/MS. As Antarctica is subjected to continuously reduced ice coverage, non-endemic cyanobacterial species may populate yet unoccupied areas, whereas in occupied areas the non-endemic species may overtake endemic cyanobacterial mat populations due to enhanced fungal and viral parasitism of endemic species unaccustomed to these parasites. This project shall provide evidence for the invasion of Antarctica with foreign species. Due to the SARS-CoV2 pandemic, the hypothesis that birds (i.e. Arctic terns) as true vectors of cyanomat-species could not be tested. However, we will sample cyanobacterial mats in close proximity to birds nesting grounds of Svalbard. Together with Arctic tern GPS tracking data, this would allow associating birds as possible vectors of cyanobacterial species.
DFG Programme
Infrastructure Priority Programmes
Subproject of
SPP 1158:
Infrastructure area - Antarctic Research with Comparative Investigations in Arctic Sea Ice Areas
International Connection
New Zealand, Spain, United Kingdom
