Project: Patterns of Microbial Community Structure Within and Between Hadal Environments

Acronym/Short Name:Mariana Perspectives
Project Duration:2015-09 - 2018-08
Geolocation:Challenger Deep, Mariana Trench

Description

Award Abstract from NSF:
The deepest portion of the ocean is present in ocean trenches, whose steep walls descend from approximately 4 miles down to depths that in some cases are close to 7 miles below the seawater surface. At these locations Earth's crust is recycled. Perhaps not surprisingly given their remoteness, deep ocean trenches are the least understood habitats in the ocean. The researchers participating in this project are working to characterize the microbes present in two of the deepest trenches present on Earth, both in the Pacific Ocean, the Kermadec Trench located north of New Zealand, and the Mariana Trench, located east and south of the island of Guam. Most of the Mariana Trench is located within the United States Mariana Trench Marine National Monument. Relatively little is known about the diversity and adaptations of the microorganisms in deep ocean trenches. An unknown fraction of the microbes present have descended from shallow waters above and are unlikely to participate in any nutrient cycles in the deep sea. Others are adapted to near freezing temperatures and up to pressures greater than 10e7 kilograms per square meter (16,000 pounds per square inch). These latter microbes perform important roles recycling organic matter. But who are they? This project is contributing to the training of diverse undergraduate and graduate students participating in research, additional undergraduate students learning about microbes inhabiting extreme environments in a web-based class, and additional graduate students and postdoctoral scientists participating in an advanced training course being offered in Antarctica.

Experiments being performed include direct counts of prokaryotes and viruses in seawater and sediments, analyses of the abundance and phylogenetic breadth of culturable heterotrophic bacteria at a range of pressures, measurements of bacterial community species diversity and richness both within and across seawater and sediment samples, as well as within and across the two trench systems, measurements of microbial activity as a function of pressure and the identification of high pressure-active cells. The data generated from these analyses are being integrated into the results of additional chemical, geological and biological measurements performed by others as a part of the National Science Foundation funded Hadal Ecosystems Studies Project. Two of the working hypotheses are that prokaryote numbers and diversity are generally positively correlated with surface productivity and proximity to the trench axis and that bacterial taxa exist which are endemic to specific trenches, present in multiple trenches and more widely distributed in deep-sea environments.


DatasetLatest Version DateCurrent State
Cell counts from hadopelagic samples in the Mariana and Kermadec trenches, collected on R/V Falkor FK141109, FK141215, and R/V Thompson TN309, 2014 (Mariana Perspectives project)2017-12-18Final no updates expected
Isolation of microbes from hadal water and sediments from Mariana and Kermadec trenches from R/V Falkor, R/V Thomas G. Thompson FK141109, TN309, FK141215, April to December 2014 (Mariana Perspectives project)2017-12-18Final no updates expected
Colony forming units (CFUs) of water samples from Mariana and Kermadec trenches grown in 3 media from R/V Falkor FK141109, FK141215, and R/V Thompson TN309, 2014 (Mariana Perspectives project)2017-12-14Final no updates expected
515F-926R 16S rRNA gene sequencing accessions from seawater and sediment samples from R/V Falkor FK141109 and R/V Thompson TN309 from the Mariana and Kermadec trenches, 2014 (Mariana Perspectives project)2017-12-13Final no updates expected
General nutrient data (averages) from Leggo drop 1 seawater collected by Niskin bottle on R/V Falkor cruise FK141215 in the Challenger Deep, Mariana Trench in December 20142017-03-13Final no updates expected
Culture-independent identification of bacteria present in the pressure-retaining seawater (PRS) sampler deployed during Leggo drop 1 from R/V Falkor cruise FK141215 in the Challenger Deep, Mariana Trench in December 20142017-03-13Final no updates expected
Viable cell counts on the bacteria in the seawater collected in the Niskin bottles during Leggo drops 1 and 3 on R/V Falkor cruise FK141215 in the Challenger Deep, Mariana Trench in December 20142017-03-13Final no updates expected
Direct counts (flow cytometry) on microbes obtained by Niskin bottle and pressure-retaining sampler from the Leggo Lander on R/V Falkor cruise FK141215 in the Challenger Deep, Mariana Trench in December 20142017-03-13Final no updates expected

People

Principal Investigator: Douglas Bartlett
University of California-San Diego (UCSD)

Contact: Douglas Bartlett
University of California-San Diego (UCSD)


Data Management Plan

DMP_Bartlett_OCE-Bartlett-1536776.pdf (15.86 KB)
02/09/2025