Dr. Lingjie Zhou defends PhD on quantifying phytoplankton carbon biomass using DNA

Congratulations to Dr. Lingjie Zhou on her Ph.D. defense. Check out Dr. Zhou’s description of her Ph.D. journey and accomplishments below. We are wishing Dr. Zhou all the best for her future career!

I defended my Ph.D. dissertation entitled “Estimate phytoplankton carbon biomass using DNA” on Nov. 15th, 2022. My Ph.D. research was aimed at establishing the correlations among the cellular contents of DNA, C, and rDNA in phytoplankton and I measured these parameters for 11 species spanning major algal lineages at different growth stages and under different growth conditions. The correlations would enable oceanographers to determine the species composition and species-specific carbon biomass in the phytoplankton community simultaneously. Throughout the Ph. D. study period, I gave presentations at conferences, including the Northeast Algal Symposium, Phycological Society of America, ASLO Aquatic Sciences Meeting, and Feng Graduate Research Colloquium. I have published several papers as co-author (listed below), and I’m still working on my own papers now. I have received the Student Research Award from the Ecology and Evolutionary Biology Department of the University of Connecticut (UConn) and the Connecticut State Museum of Natural History in 2019 as well as several summer research awards from the Department of Marine Sciences at UConn.

References:
Nanjing Ji, Jinwang Huang, Zhenzhen Zhang, Lingjie Zhou, Xin Shen, Senjie Lin, Identification and expression analysis of meiosis-related genes in the harmful alga Heterosigma akashiwo (Raphidophyceae). Harmful Algae, 2020, 92, 101736, ISSN 1568-9883, https://doi.org/10.1016/j.hal.2019.101736.

Nanjing Ji, Zhenzhen Zhang, Jinwang Huang, Lingjie Zhou, Shengxian Deng, Xin Shen, Senjie Lin. Utilization of various forms of nitrogen and expression regulation of transporters in the harmful alga Heterosigma akashiwo (Raphidophyceae). Harmful Algae, 2020, 92, 101770, ISSN 1568-9883, https://doi.org/10.1016/j.hal.2020.101770.

Chuner Cai, Feng Liu, Ting Jiang, Lingke Wang, Rui Jia, Lingjie Zhou, Kai Gu, Jianfeng Ren, Peimin He. Comparative study on mitogenomes of green tide algae. Genetica, 2018, 146(6): 529–540, https://doi.org/10.1007/s10709-018-0046-7

Zhou at the 56th Northeast Algal Symposium in April 2017

 

Dr. Zhou at her PhD defense

 

Zhou at the ASLO 2019 Aquatic Sciences Meeting in February 2019

 

Zhou working in the Lin lab

Annette Carlson presents master’s thesis on oxygen and nutrient cycling in St. Helena Bay

Congratulations to Annette Carlson, who presented her master’s thesis on November 9, 2022. Annette‘s thesis was entitled “Quantifying interannual variability of shelf nutrients and associated hypoxia in St. Helena Bay with new metrics and tools” and she was advised by Professor Samantha Siedlecki.  St. Helena Bay is located in the Southern Benguela Upwelling System off the coast of South Africa. During her master’s, Annette traveled to South Africa to work with collaborators at the University of Cape Town and gain experience collecting water samples, and analyzed an existing dataset to characterize and develop mechanistic understanding of the variability in nutrients and oxygen in this dynamic upwelling region.

Annette also presented a webinar on her thesis work to the Global Ocean Oxygen Network in October 2022, which is available on YouTube, and she participated in several conferences.

CongratulationsAnnette, and best wishes in your future career!

Carlson’s thesis was funded by the US National Science Foundation through a grant to Dr. Samantha Siedlecki and Dr. Julie Granger.

Annette Carlson and colleagues (Raquel Flynn (left), Sina Wallschuss (right)) sampling for oxygen and nutrients in False Bay, Cape Town, South Africa. Photo credit: Pieter Truter.

DMS Kayla Mladinich shows that bivalves can reject microplastics

8 November 2022. DMS is happy to share the latest publication by PhD student Kayla Mladinich, showing the surprising but good news that blue mussels and oysters appear not to ingest all microplastic particles floating in the water.

By Kayla Mladinich.

Oysters and mussels are filter feeders that draw particles in from the surrounding water to be eaten. These animals can select which particles are eaten or rejected depending on factors such as particle size and surface properties. This study was performed to determine what kinds of microplastics will be consumed or rejected by oysters and mussels. Both species rejected larger microplastics more than smaller microplastics and did not differentiate between different types of plastic polymers. The results suggest that oysters and mussels will not ingest all microplastics that they are exposed to in the natural environment!



Kayla_lab
Kayla changing water and replenishing food for the animals.

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An oyster being exposed to microplastics in the laboratory. Microplastics are gently pipetted over the inhalant aperture (where oysters draw particles in) which allows the oysters to choose between drawing the particles in or not (Photo: Kayla Mladinich).

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Mladinich et al. ES&T (2022) Graphical abstract

Shell recycling will help restore oysters in Long Island Sound

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On 6 October, Research Professor Z.Baumann surveys the wild oyster reef at Morris Creek, CT

By Elaina Hancock.

7 November 2022. An unexpected find of a healthy, well-established oyster reef tucked away in a shoreline park inspired UConn Marine Science researcher Zofia Baumann to study ways to help these vital ecosystem engineers make a comeback.

Oyster habitats were largely destroyed by development, over-harvesting, and pollution, but in Long Island Sound, their numbers might be on the rise. Baumann and others hope to help restore Connecticut’s oyster populations.

Oysters build habitats where many species flourish, they improve water quality and make shorelines more resilient to erosion, but they need old shells to start building on. The site that became the focus of the project is one where oyster shells were deposited. Unfortunately, there is a shortage of shells in Connecticut and addressing this problem is the primary goal.

The project brings together members of the community, shellfish farmers, and regulators, as Baumann says, this effort relies on the community, otherwise, it will not work.

Dr. Yipeng He becomes the department’s newest PhD!

Congratulations to Dr. Yipeng He, who successfully defended his PhD thesis entitled “Air-sea exchange of mercury and its species in the coastal and open ocean” on October 28, 2022. Dr. He was a student in Professor Rob Mason’s group and his PhD research included research cruises in the Pacific Ocean (GEOTRACES cruise GP-15), Arctic Ocean, and Long Island Sound to collect measurements of mercury at the air-sea interface. Drs. He, Mason and colleagues have already published some of the thesis results in Environmental Science & Technology and Atmospheric Environment.

Check out some photos from Dr. He’s journey below!

Dr. He will be departing soon for another GEOTRACES research cruise to collect more mercury data!

Dr. Yipeng He and Dr. Rob Mason following a successful thesis defense!

 

Yipeng He and colleagues on an Arctic research cruise

 

Yipeng and colleagues coring ice in the Arctic

 

Yipeng and the Mason lab with their atmospheric mercury sampler

Outreach event for eelgrass restoration

On October 19, members of the Marine Sciences Department participated in an outreach event for a research project that is led by Professors Craig Tobias and Jamie Vaudrey, graduate student Shannon Jordan, and Chris Pickerell from the Cornell Cooperative Extension. The research is funded through the Long Island Sound Study. The researchers are aiming to improve the success of eelgrass restoration by adding a chemical amendment to the sediments when eelgrass shoots are transplanted to a new location.

The outreach event involved bringing community members and scientists together to prepare the eelgrass shoots for transplanting at the new sites in the Niantic River. Shannon and the team have also been conducting lots of field measurements and laboratory experiments in the lead up to the transplanting event. We look forward to learning how the eelgrass grows in its new habitat over the next year!

Shannon Jordan, Josie Mottram, Anagha Payyambally, and Alex Frenzel prepare eelgrass shoots for transplanting

Community members prepare eelgrass shoots for transplanting. Credit: Jamie Vaudrey

 

Shannon Jordan and Alex Frenzel participate in fieldwork for the project

 

Shannon, Amelia, Brian and Peter collect sediments for laboratory experiments

Graduate student Mackenzie Blanusa participates in NASA S-MODE cruise

Graduate student Mackenzie Blanusa (a MSc student in Professor Cesar Rocha’s group) has written a blog post about her experience on the NASA Sub-Mesoscale Ocean Dynamics Experiment (S-MODE) research cruise.

Check it out here!

Mackenzie says: “I had been patiently waiting and dreaming about this research cruise for months. Yet a few days before traveling from Connecticut to Oregon for ship mobilization, I couldn’t shake a feeling of denial – like I couldn’t believe I was really going to be out in the Pacific Ocean on a research vessel for an entire month. … S-MODE is wrapping up in a few days and I’ll be on my way back home. The sense of denial I once felt has been replaced with self-confidence and motivation to pursue a career as a seagoing oceanographer. I have learned so much from all the other scientists on board who are more than happy to share their knowledge with a curious graduate student. Although S-MODE is ending, I know this is just the beginning of my journeys at sea.”

Congratulations to Mackenzie and the team on a successful expedition, and we look forward to seeing you back on campus!

Mackenzie (left) and Avery Snyder (right) getting ready to deploy a mixed layer float. Credit: Alex Kinsella

Marine Sciences faculty and students participate in Early College Experience event

On September 23, 2022, the Department of Marine Sciences helped to welcome 200 students from 12 high schools across Connecticut to the Avery Point campus for the annual Early College Experience Cardboard Boat Race event. These students are taking UConn courses at their local high schools and also prepared boats made only from cardboard and duct tape, which they raced in the waters off of Avery Point in the afternoon.

Prior to the races, Professor Matassa shared a presentation on the life of an ecologist and Professor Manning described how oceanographers use new technology to study changing ocean chemistry. Graduate students Mackenzie Blanusa and Riley Pena led a demonstration on the buoyancy of different vegetables. We look forward to seeing some of these high school students join the UConn Husky family in the future!

Congratulations are also on order for Marine Sciences undergraduate Devan Barnum who won the Avery Point community cardboard boat race on September 21, on behalf of the men’s basketball team!

Check out this article in The Day for more photos of the boat race.

The photos below were taken during the event  and are provided by Michael Illuzzi, Gordon Daigle and Cara Manning.
Top: Graduate Students Riley Pena and Mackenzie Blanusa led a demonstration on buoyancy.
Middle: Prof. Matassa conducts a presentation on the life of an ecologist
Bottom: Prof. Manning dressed as a pH indicator for a presentation on changing ocean chemistry.

A soccer match to honor Dennis Arbige’s service for DMS

23 September 2022. On this day, we honored the long years of service of Dennis Arbige, who is officially retiring as the building manager this summer (he’s still very much around, helping with the transition). We all know Dennis as the kind force keeping the wheels from falling off of our beloved building, battling with environmental chambers, autoclaves, and a gazillion other things, while coordinating many of the various upkeeps over the years. But Dennis is also a gifted electrician and underwater technology buff, who has accompanied several ROV missions in the past.

And in addition, many of us simply love Dennis as the cornerstone of one of DMS’ most sacred traditions: the Friday afternoon co-ed soccer game!
For that reason, we planned to celebrate Dennis’ service this Friday in style!

Best of luck, Dennis, for your next move in life.
Please, if you can, keep playing soccer with us!

on 23 September 2022, DMS, Avery Point faculty, staff and students celebrating with Dennis (with ball)

The Arctic is not so Boron!

Professor Penny Vlahos investigates what happens with the ocean chemistry at the marginal ice zones in her recent publication

By Ewaldo Leitao.

The Arctic Ocean is undergoing rapid changes due to climate change. Increasing temperatures result in decreasing sea-ice extent, constant decreasing and thinning of permanent sea-ice caps. Some projections even show a completely ice-free Summer by 2050!

Another consequence of climate change is ocean acidification due to increasing atmospheric CO2. That leads to the decrease in water pH and changes in carbon chemistry dynamics. The Arctic may be a small ocean (3% of total oceans area) but it has an important contribution to carbon uptake (10%). Therefore, it is necessary to understand the impact of these changes across the oceans, including the Arctic, in order to be prepared for it.

Some chemical elements, such as boron, contribute to the ocean’s capacity to resist changes in pH, that is ocean’s alkalinity. Boron, in combination with salinity, has been used as a universal rule in the open ocean (boron to salinity ratio) in order to understand the contribution of boron to alkalinity, and therefore ocean carbon chemistry. But how does that change in the less saline areas, such as the marginal ice zones of the Arctic?

In the recent paper published in Nature Communications, Prof. Penny Vlahos and graduate student Lauren Barrett observed that, when measured in low salinity areas (marginal ice zones), the boron to salinity ratio deviates from the expected in open oceans. In a cruise that took place in May of 2021 (you can read more about the cruise here), researchers were surprised to find significant deviations in the boron to salinity ratios in ice and brine samples. Lower water temperature and lower salinity alters the exchange between boric acid and borate, which is used to determine the contribution of boron to sea water alkalinity (capacity of water to resist changes in pH and acidification), driving this deviation of the boron to salinity ratio compared to open ocean waters.

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Prof. Penny Vlahos (right) with graduate students Lauren Barrett (left) and Emma Shipley (middle) on board the RV Sikuliaq

Boron-concentration
Stations sampled on the RV Sikuliaq between May 20th to June 14th, 2021.

The unique microenvironment of the marginal ice zones creates a very dynamic system. As seawater freezes, salts are rejected, but there is still a liquid region between ice crystals, called brine channels. These channels allow boron to undergo inorganic changes that may result in the variations observed in some of the samples, increasing the variability of boron to salinity ratio observed in these Arctic areas.

Prior to boarding the research vessel, researchers had to quarantine for two weeks. But this was a valuable time to Lauren Barrett. “Over quarantine I spent a lot of time reading about the various uncertainties that other authors encountered in accurately and precisely constraining the carbonate system in this highly heterogeneous environment. The boron to salinity ratios that we present here warn against applying universal ratios constrained in the open ocean to marginal ice zones and ice environments.” says Lauren.

Penny Vlahos Arctic
Lauren making a snowman at one of the stations that was ice covered, with the RV Sikuliaq on the back.

Lauren also shared a little bit about her experience: “I am very grateful for the opportunity to work with our international coauthors. The collaborative and interdisciplinary nature of marine science is one of my favorite aspects of working in this field. This research cruise was a great experience both personally and professionally, and I continue to be grateful to work in a field where cruising and getting to see polar bears is all in a day's work.”

The Arctic is an important sink of carbon and yet highly susceptible to climate change. Therefore, understanding detailed information of this system, instead of applying universal ratios, is necessary in order to better understand the carbon chemistry of the Arctic and be prepared for the consequences of climate change.


Vlahos, P., Lee, K., Lee, CH., Barrett, L, and Juranek, L. (2022) Non-conservative nature of boron in Arctic marginal ice zones. Nature Communications Earth & Environment 3, 214