Deep under the ocean, microbes are active and poised to eat whatever comes their way

April 28, 2021

The subseafloor constitutes one of the largest and most understudied ecosystems on Earth. While it is known that life survives deep down in the fluids, rocks and sediments that make up the seafloor, scientists know very little about the conditions and energy needed to sustain that life.

An interdisciplinary research team, led by ASU and the Woods Hole Oceanographic Institution, sought to learn more about this ecosystem and the microbes that exist in the subseafloor. The results of their findings were recently published in Science Advances, with ASU School of Earth and Space Exploration geobiologist and Assistant Professor Elizabeth Trembath-Reichert as lead author. Elizabeth Trembath-Reichert running the winch for the CTD water sampler, which was used to bring fluids up to the ship from the bottom of the ocean. Photo by Ben Tully Download Full Image

To study this type of remote ecosystem, and the microbes that inhabit it, the team chose a location called North Pond on the western flank of the mid-Atlantic Ridge, a plate boundary located along the floor of the Atlantic Ocean. 

North Pond, at a depth of over 14,500 feet (4,420 meters) has served as an important site for deep-sea scientists for decades. It was most recently drilled hundreds of feet through the sediment and crust by the International Ocean Discovery Program in 2010 to create access points for studying life and chemistry beneath the seafloor.  

With support from the National Science Foundation, the Gordon and Betty Moore Foundation, and the Center for Dark Energy Biosphere Investigations, the team sampled the crustal fluid samples from the borehole seafloor observatories with the deep sea remotely operated vehicle Jason II on the research vessel Atlantis

These unique samples from the pristine, cool basaltic seafloor were then brought back to the lab and analyzed using a nanoscale secondary ion mass spectrometer (NanoSIMS), which was used to measure their elemental and isotopic composition. 

“Our experiments use specialized tracers that can only be observed if a microorganism eats something on the buffet of options we provide,” Trembath-Reichert said. “If we see these tracers in the microbes, then we know they must have been active and eating during our experiments and we get an idea of what food sources they can use to survive.” 

Trembath-Reichert with Olivia Nigro from Hawaii Pacific University on the research vessel Atlantis after the first fluid samples (in the clear plastic boxes) came on deck from the borehole seafloor observatories. Photo Credit: Kelle Freel

Through these analyses, the team discovered that the subseafloor microbial community is active and poised to eat, despite an environment with low biomass and low-carbon conditions. 

“The microbes we studied are extremely adaptable and are able to make a living in what seems like a really harsh environment to surface dwellers, like ourselves,” Trembath-Reichert said. 

One of the most surprising discoveries was how the microorganisms use carbon dioxide. Trembath-Reichert and her team expected the microorganisms to use widely available carbon dioxide the way plants do, by "fixing" it into other forms of organic carbon that they can then use to grow on. But the findings suggest the microbes in this isolated environment with low nutrients were being more crafty.

“Our theory is that these microbes are being resourceful and using the carbon dioxide directly as a building block without having to convert it into a food source first,” Trembath-Reichert said. “And this could have major implications for the deep ocean carbon cycle.” 

"This work highlights how little we know about the lifestyle of microbes within oceanic crust and the importance of carrying out experiments with sensitive detection limits, such as NanoSIMS,” said senior author Julie Huber, of the Woods Hole Oceanographic Institution.

The first ever single-cell NanoSIMS images from this system were used to show what food sources microbes (pictured here) used. Warmer colors indicate more of a certain food source was used. 3 μm scale bar.

The next steps for Trembath-Reichert and her team are to design experiments to better understand the full diversity of ways carbon dioxide can be used by microbes. As a more readily available food source for microorganisms, they will be looking into the ways carbon dioxide can be used for survival and growth in the Earth's largest aquifer beneath the seafloor. 

To conduct this research, Trembath-Reichert was supported by fellowships from the NASA Postdoctoral Program and the L’Oréal For Women in Science Program. 

Additional authors on this study include Sunita Shah Walter of the University of Delaware, Marc Fontánez Ortiz of ASU’s School of Life Sciences, Patrick Carter of the University of Massachusetts and Peter Girguis of Harvard University.

Karin Valentine

Media Relations & Marketing manager, School of Earth and Space Exploration


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Envisioning yourself

April 28, 2021

Manifesting your dreams and goals through vision boarding

Editor's note: This story originally appeared in the summer 2021 issue of ASU Thrive magazine.

Life transitions, such as the start or end of a school year and beginning or end of a college career, are a great time to take stock and reassess how you’re doing in life. Am I living the lifestyle I want to live? Do I have a healthy work-life balance? What would help me live more fully? Am I spending enough time doing things I like with the people I enjoy the most? 

As you prepare to graduate from college and enter a professional career and/or transition from virtual to more in-person activities, now is a great time to evaluate what is going well for you, what you’d like to focus more on and how you can live a more balanced, fulfilling life. Vision boards are a great way to do all of this.

Portrait of

Michele Gaines

A vision board is a physical or digital representation of your dreams and goals. Using a collage of pictures, quotes and other inspiring images, a vision board helps you identify your priorities, refocus your energy, increase productivity, focus on your personal growth and stay motivated. Here, ASU's Mary Lou Fulton Teachers College wellness coach Michele Gaines shares her six tips to create a vision board with intention to help you manifest your goals into reality.

Take a moment to reflect on all that is already going well for you

Take at least five to 10 minutes to assess things that are going well and areas you’d like to improve. The wellness wheel’s eight dimensions of wellness (physical, occupational, emotional, environmental, social, intellectual, financial, spiritual) can be a great tool to holistically evaluate your current well-being. You can also write down any other categories that you’d like to prioritize, such as mind, body, soul, or love, career, relationships, health and wealth. 

Decide what you want to attract more of in your life

We often focus our energy on what we don’t have enough of rather than what is already going well for us.Take a moment to express gratitude for the things that are already great in your life so that you can continue to flourish in those areas and use your strengths to build on any challenge areas.

Dream big! Write down your goals both big and small

Sit quietly, close your eyes and imagine your dreams and goals coming to life. Focus on what you want to feel like in those moments. See yourself in those moments of achievement and spend time thinking about the energy you want to feel and exude, who you want to be around as well as how you want to feel emotionally. So often we spend the bulk of our time thinking about the achievements and goals themselves rather than how we want to feel and experience the process of achieving and experiencing the accomplishments and results of those goals.

Decide if you want to create a physical or digital vision board

For a physical vision board, I recommend using poster board, stickers, markers, magazines and a color printer. Or you can create your own vision board online using Canva, Google Slides, Picsart or any other photo editing platform to organize your goals digitally.

8 dimensions of wellness on a color wheel

The wellness wheel’s 8 dimensions of wellness (physical, occupational, emotional, environmental, social, intellectual, financial, spiritual) can be a great tool to holistically evaluate your current well-being.

Tap into your creative and artistic side

Yes, we all do have that side to us! Now that you have a clear sense of your goals, search for images, pictures, colors, words, phrases, lyrics and anything else that reflects those dreams and goals. Take your time and enjoy the artistic process. You can use magazines, newspapers or search online for inspiration. Plan on spending the most time on this section as you search for inspiration. I like playing music and chatting with friends who are also making their vision boards so it becomes a fun social activity and so that I stay motivated to actually finish it. Remember it doesn’t have to be perfect because you can always decide to make another one! The important part is you are creating something that reminds you of your goals! Take your time, have fun, and don’t rush through it! Be sure to dedicate enough time for this activity. I recommend at least an hour but once you get started you may find yourself wanting to spend more time on it because it can actually be a lot of fun dreaming big and tapping into your creative side.

Keep it visible

You finished, woohoo! Hang your vision board somewhere that you will see it daily and often, like your bathroom mirror or at your desk. Take a picture of it so you have a copy of your vision board in your phone and you can refer to it at any time. If you decided to create a digital vision board you can set it as your desktop wallpaper or phone lockscreen. The more you view your vision board, the more likely you will be reminded of your goals and motivated to take the steps to achieve them! Complete a new vision board once you achieve your goals or create new ones and repeat as often as you see fit.

Happy manifesting! Once you do this activity and see its benefits and results firsthand, you’ll be totally hooked. 

Learn more about the wellness program in Mary Lou Fulton Teachers College.

Michele Gaines is the wellness coach in the Mary Lou Fulton Teachers College, where she works with students, faculty, staff and alumni in the college to support their wellness as they pursue studies and teaching.