Research group MPEA

Marine Phytoplankton Ecology and Applications

Beneath icy waters: A research excursion to the Arctic

2021-07-14

photo: https://lnu.se/en/research/searchresearch/research-projects/project-arctic-expedition—synoptic-arctic-survey-sas-oden-2021/

In just two weeks, our team of picophytoplankton researchers will board the research SAS Oden and set sail on July 26, when the icebreaker departs from Helsingborg. On August 2, the observations in the Arctic Ocean begin. The estimated return to Helsingborg is September 20, 2021. Preparations for the excursion have been underway for over a year – the global pandemic in 2020 canceled the research trip last year, and the marine scientists have redoubled their efforts to ensure a sampling trip that is both COVID-safe and successful in its scientific conquests.

The study is part of the Synoptic Arctic Survey, an international study that will be making a comprehensive investigation of the current state of the Arctic ecosystem from 2020-2022 and assess how it is changing.

In the Swedish part of the survey, 39 researchers from 14 institutions will be participating. From Lnu, project managers Hanna Farnelid, Karin Holmfeldt, and Samuel Hylander lead their group.

For updates on this synoptic survey, you can visit the official blog: https://www.polar.se/en/news/?c=blog%20posts&t=synoptic%20arctic%20survey%202021 as well as the project page https://lnu.se/en/research/searchresearch/research-projects/project-arctic-expedition—synoptic-arctic-survey-sas-oden-2021/ .

Christien Laber, one of MPEA’s researchers is prepping for the excursion. Christien spend his time on the arctic investigating picophytoplankton, the smallest photosynthesizing organisms on the planet, and their contribution to sustaining the marine ecosystem in the Arctic. He will begin his journey by undertaking a quarantine in Malmö beginning July 16th:

 

What has been the biggest challenge in preparing for your trip to the Arctic?

Two things.  Details, and shortages due to coronavirus.  Details are very important because we will be at sea for two months.  If we forget anything or don’t have spares when things break, there’s no way to get extras.  So we really have to plan all of our experiments and the things we need for them very carefully.  This has been a bit more difficult recently with coronavirus as well, because some equipment we buy well ahead of time takes a long time to get here, which makes it difficult to feel prepared when we never know when equipment will show up.

 

 

What is your schedule like from day to day?

Every day will be different.  We have a number of experiments we will conduct and they will be done at different times throughout the cruise.  We also have a number of core sampling procedures we will do every day, but may have different personnel doing them depending on the other tasks that are ongoing.  But one thing that will remain the same is that there will be lots of filtering seawater, every single day.

 

You work with Hanna Farnelid and her team on the picophytoplankton research. What kind of sampling will you do and equipment you will use to answer your research questions?

We will be doing experiments to investigate how the smallest phytoplankton in the arctic grow, what types of nutrients they consume, and then in turn how quickly they are eaten by larger plankton.  Our deck-board incubators are important for conducting these studies, as it allows us see what happens in the seawater over time.  Because water is always moving, we can’t simply sample the ocean over three days and expect it to be the same water, so these incubators allow us to know we are working with the same water over each of our experiment time points.

  

We will surely miss you all and look forward to seeing you! We know that updates from the vessel will be few and far between, if at all, but we look forward to seeing the samples, and the photos, upon your return!

 

-Caroline Littlefield

 

 

 

Meet the Researcher: Carolin Peter

2021-04-28

Meet the Researcher: Introducing Carolin Peter

This April, Carolin Peter joins us from her home in Germany to begin her PhD research in MPEA. A self-described lover of cold weather, “the colder and darker it is, the better I feel!” Carolin looks forward to her research on the effects of climate change on various phytoplankton species and the community composition here at Lnu. With three published papers already under her belt, Carolin will head to Kalmar next month. Below, an interview with Carolin Peter.

 

What is your background as a marine biologist and researcher?

I did my bachelor’s thesis working with algae – harmful dinoflagellates off the coast of Sweden, actually! And with my Master’s agree I specialized in Marine Biology, and again my focus was plankton. I am really, really interested in plankton. Any chance I got, I chose plankton over something like fish, for example.

I did my master’s thesis on the interactions between Caribbean sponges and their microalgal symbionts. My supervisor was a chemist, and he had found out that the substance which is presumably produced by the sponge converts light from the UV range to the range that is usable for microalgae. We wondered about the purpose of this, because it’s a rather energy-consuming process, and we thought, “Well! They have so little light down there, it might be to help the symbiotic algae produce more oxygen or more sugars.”

So that’s what I focused on. I had 9 different kinds of microalgae, which I exposed to a chemically synthesized version of that sponge-derived substance and checked the oxygen evolution using optodes to see whether the oxygen evolution would increase, and whether that depends on the light conditions. We assumed that the more light you offer, the less important the additional photons provided by the sponge molecule become, so we assumed that the effect would be greatest at lowest light conditions and then decrease with light intensity.

 

Fascinating! And what will be your research focus when you come to Lnu?

I will be looking at the impact of climate change on phytoplankton communities. Specifically, higher light conditions and higher temperatures. What we know so far is that these changes should favor smaller plankton, but the larger plankton species sometimes are better at taking up nutrients and due to lower nutrient availability caused by a decrease in mixing as a result of climate change, it might also be that the larger ones are favored. So that will be my focus. I will analyze the LMO data series to check how the composition of the phytoplankton changed seasonally and over time, and I will also do mesocosms and laboratory experiments to determine, for example, the nutrient uptake in typical small-scale and large-scale phytoplankton species for comparison.

  

What do you most look forward to about living and working in Sweden?

Regarding working in Sweden, specifically, the colder climate. I had my childhood in southern parts of Germany, then went north to Bremen for university, and now I am slowly moving farther up north!

 

At this rate, you may end up in the Arctic!

I was in the Arctic, actually! I was taking a course on phytoplankton in the arctic, analysing  phytoplankton and zooplankton samples and compared the composition between areas that had been free of ice for some time and others that had been underneath the ice.

 

It seems your areas of interest really involve communities and interactions among the species.

Absolutely. I love the interactions between the species. While I feel it’s important to perform laboratory experiments where you focus only on one species to be able to really understand what they are capable of, I feel like the more realistic approach is to focus on the whole community and see how things are actually out in the world. That has at least been my perspective thus far.

 

Carolin, we are really excited for you to join our research group, and the LNU community. Welcome!

 

-Caroline Littlefield & Carolin Peter

Meet the Researcher: Christien Laber

2021-03-15

The MPEA research group is an international group of researchers with diverse research backgrounds, talents and interests. We welcome Christien into our group in 2020 as a lab technician, and he is now joining us as a post-doc in April, 2021. Christien’s background both as a scientist and a musician makes him uniquely situated to communicate our marine phytoplankton research to the world in a way that people and children understand. He has been essential to our AlgoKidz project, and continues to contribute to our work in outreach, research and beyond. 

His blog, Music of Science, is dedicated to research communication through music. 

 

An interview with Christien Laber:

What is your background as a marine biologist? (your PhD dissertation, where you got your start?)

I have been studying phytoplankton for my entire career as a marine biologist but I have had varied interests since I first started working with them during my undergraduate studies.  My first experience was working with a couple harmful algae bloom (HAB) forming species in the coastal oceans of the United States.  The first was Karlodinium veneficum which is responsible for extensive fish kills that occur in the Chesapeake Bay and along the Eastern Seaboard of the United States.  I was studying how these algae modulate their toxin production when grown in varying light conditions to help explain the variability of their toxicity in the environment.  The other HAB I studied was Karenia brevis which is responsible for the infamous Florida red tide that closes beaches and cause respiratory and eye irritation.  I worked on a project developing the discriminatory power of robots that optically detect special algal pigments used identify K. brevis among natural phytoplankton communities in the Gulf of Mexico and warn scientists of upcoming blooms.

For my PhD, I focused on an algae species many of us call the ‘rock star’ of the ocean, Emiliania huxleyi.  The nickname comes from the ornate calcium carbonate plates that cover the cell called coccoliths.  These liths are constantly produced and shed from cells and produce a beautiful chalky turquoise color in the water when the algae are blooming.  The color is so distinct, that these blooms are easily observed from space and satellite images regularly show these swirling blooms extend for thousands of square kilometers.  I was studying how these blooms can become infected by a virus specific to E. huxleyi, and what happens to the carbon that composes the billions of cells in these blooms when they lyse, and die during advanced infection events.  The research that came out of my PhD provided some of the first evidence that algal viruses can increase the efficiency of carbon export out of the surface ocean and into the deep ocean.  We suggested this process is stimulated by sticky polysaccharides produced by the cells as a byproduct of viral infection that stimulates the formation of quickly sinking aggregates of dead/dying cells and their coccoliths.  And it’s been quite exciting to see other studies corroborate our evidence that viruses can stimulate flux as well, as its quite opposite of the suggested paradigm just a decade ago.

How does working in the States or other countries differ to working in Sweden?

So far, the things that stick out to me the most are the very international nature of our community and just how much vacation we get here!  I think the emphasis on having a good work-life balance is very welcoming, and it’s good to have reminders now and then that Swedes take this seriously.   In the US, I think many people are limited to getting 2 weeks paid vacation per year or less, which is quite unfortunate.

Here in Sweden, I have also really enjoyed getting to meet and work with so many people from so many different parts of the world!  Working in the US, most of my colleagues were also Americans.  Lovely as we Americans can be, I have been able to learn so much about working as a global citizen with colleagues who are largely also internationals.

 

You’re a great singer-songwriter! How did you develop your science communication music, how long have you been doing it?

I guess the idea of writing music about science, and oceanography in particular, first started coming to me late in my PhD when I was listening to a lot of Stan Rogers.  He wrote some beautiful folk ballads about maritime travel, work, and lifestyle with exquisitely crafted lyrics that really pull you into the music.  And so, as a musician, I started wondering if I could do something similar but describe the experience of doing science at sea instead.  My first song was ‘The Pursuit of Knowledge’ which I wrote about the North Atlantic Aerosol and Marine Ecosystems Study (NAAMES) that I had recently participated in and served as a test of the concept.  I didn’t know if the science would make a particularly compelling story or not, but when I was done I was quite happy with the end result.  And I guess some others who were part of the NAAMES project also quite liked it, and so I threw together an accompanying video so that we could publish it for the public to see.  The really fun part was that NASA (who funded the NAAMES study) caught on and decided to publish the music video on their social media platforms.  So I very quickly got to see the music become an effective communication platform, and with some positive feedback decided to write a few more songs so far.

 

Word on the street is that you’re headed up to the Arctic this summer for a 3(2) month long research excursion. Tell us more!

Yes, I’m very excited about this.  I will be going to the Arctic with several other members of our team to investigate picophytoplankton, the smallest photosynthesizing organisms on the planet, and their contribution to sustaining the marine ecosystem in the Arctic.  We are conducting this study as part of the Synoptic Arctic Survey, an international study that will be making a comprehensive investigation of the current state of the Arctic ecosystem from 2020-2022 and assess how it is changing.  Picophytoplankton make up an important fraction of the primary production that supports the arctic food web, but their distribution and diversity are still poorly characterized.  As a rapidly warming and changing system, we also need to understand how the assemblage of picophytoplankton will change over the next century and impact ecosystem dynamics.  So the sampling and experiments we will be conducting will try to provide some answers to these questions, as well as a good foundation for research going forward.

 

What are you most excited about for this excursion? Any nerves?

Well I suppose one can only hope to see a polar bear or two, but not get too close of course!  Yes, I think I’m most excited to just absorb the remoteness of the area and the beauty of the sea ice and whatever little (or big) creatures are hanging out in the area as we travel through.

We will also be on the icebreaker research vessel Oden for the expedition, which may take us near the North Pole by cutting through sea ice.  This will also be exciting, and I do have faith in the ship’s design, but it will perhaps also be a bit intimidating to have tons of sea ice pressing against the ship’s hull as we cruise along!

 

  1. We’re really happy to have you onboard. ? Welcome! (a bit belated!)

Thank you very much! Tack så mycket!

-Caroline Littlefield & Christien Laber

GENIE Program: “A conscious focus on unconscious bias​” Zoom Seminar

2020-11-17

During this past month’s AMRI seminar, we learned about the GENIE program at Chalmers University, which was established with the following goals:

  • Increase the proportion of female faculty
  • Remove the structural and cultural obstacles that hamper women’s careers
  • Create a working environment that is diverse and inclusive and supportive of excellence in research and teaching

Next week, a Zoom seminar with GENIE will take place on Nov. 23, 15.00 – 16.00 entitled “A conscious focus on unconscious bias.” 

Speakers are:  Annette Bak, Head of Advanced Drug Delivery at AstraZeneca, and Katarina Matson, Head of Culture & Diversity at Volvo Cars. Sign up to the seminar using the Choodle link below. You will receive a  Zoom link to the seminar the day before the seminar.

Gender, Research and Leadership in the Time of COVID

2020-10-30

Are your collaborations or working environments with men and women the same? If not, how do they differ?

What is the best description of being inclusive?

How do we become better at negotiating?

What actions can we take every day to improve gender equality, instead of just waiting for policy changes?

These questions, and many more, were discussed this past month, as our research group joined the 2020 all-hands meeting of AMRI (Aquatic Microbiome Research Initiative) AMR), the Sweden-wide open network of aquatic microbial ecology researchers, funded by SciLifeLab.  This year’s meeting was unlike most annual microbiology forums: The 2-day webinar was divided by theme – Microbial Ecology for Safe Water and the pervasive global issue facing research and science: Gender inequality.

This year, AMRI’s collection of invited speakers were women whose work in the field of microbial ecology has strongly impacted scientific discussions around safe water, brought new perspectives into the connection between microbial ecology and public health, and addressed social welfare through the lens of safe water as a global challenge.

Click here to view the AMRI Seminar: Microbial Ecology for Safe Water

 

We heard from  Hélene Norder Gothenburg University), Kaarina Sivonen (University of Helsinki), Catherine Paul and Karin Rengefors (Lund University), Agneta Andersson (Umeå University), and Maria Saline, who spoke about the Chalmer’s gender and research initiative, GENIE.

The day culminated in the keynote speaker of honor, Dr. Rita Colwell, American microbiologist of great renown, who spoke for one inspiring hour on Climate, Oceans, and Human Health: What Cholera can Teach Us About COVID-19. Dr. Colwell, whose work with microbiology in public health has faced the global challenge of safe water head on, in her career that has spanned decades. Her work in reducing cholera in Bangladeshi villages through simple filtration, to her work today, tracking COVID-19 in wastewater, has had enormous impact in public health. In addition to her research, Dr. Colwell was the first female director of the US National Science Foundation.

Despite her vital contributions to microbial science and public health, however, Dr. Colwell’s career was a hard-fought victory, overshadowed by decades of sexism and discrimination in the science and academic workplace. Such challenges are outlined in her new book, A Lab of One’s Own, a memoir and motivational journey.

 

 

“The day you became a scientist was the day you chose to be a leader.” – Catherine Legrand, panel on gender and research in the time of COVID, AMRI seminar 2020

Lauri Robbins Ericsson, Emotional Intelligence, Gender Intelligence and Research in the time of COVID

The second day of the AMRI seminar focused solely on gender and research, welcoming Lauri Robbins Ericsson, speaker on gender intelligence issues, and a panel of four women: Karin Rengefors, Catherine Paul, Maria Saline, and Catherine Legrand. Lauri’s objective-based presentation, Emotional Intelligence, Gender Intelligence and Research in the time of COVID, highlighted the challenges posed by gender equality in academia and science, stressed the importance of emotional intelligence and leadership, and how gender barriers are broken down in emotional intelligence analysis. (See below to view Lauri’s entire talk). Lauri then moderated the panel of scientists, who discussed issues of gender bias in the field, leadership, inclusivity, knowledge and challenges.

This seminar brought to light the issues surrounding gender inequality in the field of research and academia, and brought forward inspiring discussions from experienced scientists in the field, as well as young researchers just starting on their path. We will continue to shed light on this essential subject, paying attention to programs such as GENIE, which promotes gender balance within the Chalmers University faculty.

What can you do to promote gender equality? What brave steps can you take in your own life and work? How can you speak up for those who might be held back?

 

–Caroline Littlefield

Avslöjat! Havets hemliga mikroliv

2020-10-20

De senaste åren har naturens hemliga liv kommit på tal allt mer. Böcker som handlar om hur träd och svampar kommunicerar via vidsträckta underjordiska nätverk har toppat listorna. Men hur står det egentligen till med det hemliga mikrolivet i våra hav och sjöar?

Vi vet att mikroorganismer såsom alger och bakterier är avgörande för hur näringsämnen och energi fördelas och återanvänds, och att utan dem skulle havens makroliv se ut på ett helt annat sätt än det gör idag. Vi vet också att det är mikroalger som producerar mer än hälften av det syre som finns i vår atmosfär idag. Men hur de olika mikroorganismerna i haven faktiskt fördelar dessa uppgifter emellan sig och hur denna arbetsfördelning påverkas av störningar orsakade av till exempel övergödning och klimatförändringar känner vi inte så väl till än. För att kunna göra bättre modeller av hur havens ekosystem och de ekosystemtjänster dessa förser oss med kan komma att ändras under ändrade förutsättningar, såsom ökande temperaturer, ökande nederbörd och ökande tillförsel av näring till sjöar och hav, behöver vi veta mer om naturens hemliga mikroliv. Detta har jag försökt ta reda på i min avhandling där jag har studerat just hur interaktioner mellan alger och bakterier är organiserade, vilka mekanismer det är som styr dem och hur de påverkas av störningar såsom hög tillgång på energi och näring eller varierande temperaturer.

Dels har jag kunnat visa att de bakterier en alg omger sig med går att förutse, vilket tyder på att interaktioner mellan dessa organismer är så pass viktiga att de påverkar vilka typer av mikroorganismer som återfinns på en plats. Dels har jag kunnat visa att alger och bakterier tillsammans skapar förutsättningar för att ekosystem ska kunna hantera till exempel varierande temperaturer utan att systemet ändrar karaktär. De kan göra detta genom att balansera hög eller låg artvariation och genom att ta över varandras funktioner, och de gör detta på ett sätt som bibehåller både variationen och funktionen för hela systemet. På detta sätt har mikrolivet en stark inverkan på balansen i hela näringsväven. Jag har också kunnat visa på att alger och bakterier, under förutsättningar som tidigare har antagits leda till konkurrens om näring, istället karaktäriseras av fördelning av näringsämnen mellan mikroorganismerna. Detta tyder på att tidigare antaganden och de slutsatser som dessa har givit upphov till kan komma att behöva omvärderas. Sammantaget visar jag i avhandlingen att alger och bakterier påverkar och påverkas av varandra på ett sätt som tidigare inte varit känt.

Klimatförändringar och övergödning av våra sjöar och hav är några av vår tids stora ödesfrågor, med den här avhandlingen har jag bidragit till att avslöja lite mer om hur mikroorganismer hanterar ändrade förutsättningar. Detta är kunskap som kan användas för att bättre förstå konsekvenserna av klimatförändringar på naturen. Naturens hemliga mikroliv är inte längre lika hemligt▪

 

– ES

Dr. Eva Sörenson defended her thesis on September 25th , 2020.

Her supervisor is Catherine Legrand. 

Opponent: Prof Sonya Dyhrman, Columbia University
Chairman: Dr. Per Nilsson, Linneaus University
Examining committee:
Prof Alexandra Z. Worden, GEOMAR Helmholtz Centre for Ocean Research
Doc Sam Dupont, Gothenburg University
Prof Stefan Bertilsson, Swedish University of Agricultural Sciences

Thesis title: Functional and structural characterisations of phytoplankton-bacteria interactions in response to environmental challenges

Workshops on Water Use Led by Prof. Catherine Legrand during Sustainability Week

2020-09-21

In connection with Sustainability Week / Kalmarsund Week, two different digital workshops were held with the theme of sustainable and efficient use of industrial water.

The workshops were led by Catherine Legrand, professor of marine ecology at the Faculty of Health and Environment and Jörgen Forss, senior lecturer at the Faculty of Technology. Around 60 people from business, organizations and authorities, joined  representatives from Linnaeus University, to discuss industry’s water use from local to international needs and challenges. IVL Swedish Environmental Institute, Vattenmyndigheten Södra Östersjön, Mercatus Engineering Vimmerby, Mörbylånga water industry and doctoral students from Linnaeus University shared interesting perspectives that were discussed further in workshops based on experiences, needs and future challenges.

Water scarcity is a strong factor that requires new analyses and processes. The statement “reality goes faster than calculations” became food for thought, and a driver to discuss the international issues involving water, including the fact that water problems lead to conflicts and should be dealt with globally.

It is clear that industry partners at the workshops are looking to find solutions for efficient water use.  But how do we do it best? Incentives, behavior change, skills development, exchanges of experience, legislation, water recycling concepts, and solution templates to inspire each other are some examples. The importance of cooperation and communication between business, authorities, municipalities and academia was a recurring argument. Together we challenge for new and effective solutions!

See Swedish version of this article here! 

More information on Catherine Legrand’s “Knowledge Environment: Water” for Linnaeus University: 

hallbart-o-effektivt-anvandande-av-industrvatten-resume-002 (2)

AlgoKidz: Bringing the world of algae, the sea, and sustainability to children

2020-09-14

For several years, researchers in our MPEA group’s Algoland project have researched the ability of algae to clean flue gas from air and clean water from nitrogen and phosphorus.  Now, we are bringing the world of algae, the sea and sustainability to children in Sweden and beyond with our new outreach project: AlgoKidz aimed at children aged preschool to grade 3.

This past Friday, 11th September, AlgoKidz was launched in the third grade classes of Lindöskolan in Kalmar, where students learned and sang about Algo, the big little superhero who lives in the sea. They even had the pleasure to taste some green “Algo Shots,” which received mixed reviews from the taste-testers!

 

 

The AlgoKidz project is designed to be an educational toolbox for teachers of young children. It includes a homepage with the story about Algo, from which teachers can download coloring books, stories, stickers, a filmed educational program where Catherine teaches about algae in a way children can understand,  and even a music video starring MPEA and EEMiS’s very own researcher, Christien Laber! The material is free to use for everyone and completely free of charge.

The idea of integrating art with science is not a new one, but one that we are implementing in a wholly original way, incorporating music, art and digital elements to engender ocean literacy for a new generation of thinkers, researchers and world citizens.

“This was the starting shot and we have a few more school visits planned, but the idea with Algo Kidz is that you as an educator can use the material in your teaching on your own, says Catherine. “Algo Kidz is a good example where science and art work together to increase water knowledge.”

The research that forms the basis for Algo Kidz is conducted within Linnaeus University’s project Algoland, Marine Phytoplankton Ecology and Applications, Eemis, and Knowledge Environment: Water. The project is based on the exhibition “Microalgae – The environmental heroes of our time,” which is produced and curated by the LNU’s The Cultural University.

AlgoKidz is a great way to kick off the UN #DecadeofOceanScience ! 

 

See some photos from the AlgoKidz launch party!

 

Link to Algo Kidz website: https://lnu.se/algokidz

Link to: Christien Laber’s Music of Science webpage 

Link to LNU Press release: https://lnu.se/mot-linneuniversitetet/aktuellt/nyheter/2020/nytt-skolmaterial-ska-lara-barn-hur-mikroalger-kan-rena-luft-och-hav/

P4Kalmar Förmiddag med Kalle Johansson, interview with Christien Laber, AlgoKidz launch https://sverigesradio.se/avsnitt/1565071
Time 04.50 till 24.10

Contact and more information about the project
Catherine Legrand, Professor of Marine Ecology, 070-438 06 18, catherine.legrand@lnu.se
Christina Dahlgren, artium director, 070-572 26 56, christina.dahlgren@lnu.se

Caroline Littlefield Karlsson, coordinator, 0732318660

Wrapping up the summer field work season with BUG2020

2020-08-17

August and September in the Baltic Sea is full of life fueled by the summer sun.  Phytoplankton at the base of the marine food web are rapidly photosynthesizing, and cyanobacteria in particular are producing their annual summer blooms at the surface of the warm and stratified waters. We took the opportunity to conduct experiments at the LNU marine field station in Kårehamn, Öland, in beautiful summer weather investigating the growth and mortality of Baltic picocyanobacteria.

Pictured: PhD student Javier Alegria-Zufia and Dr. Hanna Farnelid recovering an array containing bottles of experimental seawater for the grazing study. After initially collecting seawater, the different experimental groups are contained in bottles and placed in these arrays, which are kept as close to ambient conditions as possible. The incubated experimental seawater experiences the same light and temperature conditions as a natural population would for the duration of the incubation, before being retrieved for sampling.

Tiny picocyanobacteria are prominent members of this community of phytoplankton. They can divide and become more abundant or they may become food for others in the food chain. Picocyanobacteria sustain their growth by consuming the available nutrients in the surrounding waters. Like many of us here on planet Earth, these microbes have preferences for their nutritional intake. Where a person might choose a banana over an apple for their daily fruit consumption, picocyanobacteria can have preferences for nitrate or ammonium as a source for critically needed nitrogen to grow. These nutrient preferences impact both the respective nutrient concentrations remaining in the water as well as the growth strategy of the cells that consume them. It is, however, still a mystery what the preferences are for picocyanobacteria that live and grow in the Baltic Sea.

The study, titled BUG2020 for Baltic Uptake and Grazing investigates the preferences for nutrient sources and the mortality rates of picocyanobacteria growing at the Linnaeus Marine Observatory (LMO), located 10 km offshore the east coast of Öland. To determine nutrient preferences, seawater was incubated with stable isotope labeled nutrients. In addition, dilution experiments were performed focusing on the grazing and mortality of Baltic picocyanobacteria. Measuring growth rates at several dilutions of relaxed grazing and virus pressure allows for the calculation of grazing rates on the algae, which is important in understanding the cycling of nutrients throughout the Baltic Sea.

 

-Christien Laber, Laboratory Engineer

 

The BUG2020 experiment is a collective effort within the Marine Phytoplankton Ecology and Applications research group. The members working on BUG2020 are:

Hanna Farnelid, Associate Professor

Elin Lindehoff, Associate Professor

Christien Laber, Laboratory Engineer

Javier Alegria-Zufia, PhD student

Catherine Legrand, Professor