experiment

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A wee in the Baltic Sea?

For two weeks, the bachelor course “Environment of the Baltic Sea” from Stockholm University have been stationed at the Askö Laboratory for field studies. The course includes many relevant methods for new biologists. Among other things, the students have been fishing with survey gillnets, dug the mud of soft bottoms, and done meticulous inventories of vegetation and animal community in three shallow bays.

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Enthusiastic students snorkle out to make an inventory of the flora in a Baltic Sea shallow bay.

Part of the course also focuses on how humans affect the Baltic Sea ecosystem. For an easy way to show how urine in the sea affects the growth of phytoplankton, i.e. eutrophication, the students were instructed to set up 4 pieces of plastic tanks of 1 m3 (1000 liters) and fill with seawater. One tank was used as control and nothing else was added to it. In the other three 3dl, 6 dl and 12 dl of urine was added in order to study the phytoplankton response to different nutrient levels.

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0,3 permille urine and a week of sun clearly demonstrates how the phytoplankton thrive in response to nutrients.

This year I also put a piece of the filamentous alga Cladophora glomerata in the tanks. This algae grows just below the surface and thrives in nutrient-rich waters. When grown in high nutrients, it gets a darker green color. This is clearly seen in the most eutrophic tank with 1.2 liter of urine per 1,000 liters of water.

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The control treatment has no added urine, and the Cladophora glomerata has a light green colour.

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In the tank with the highest concentration (1,2 dl), the Cladophora glomerata has grown well and is dark green. The water is full of phytoplankton and does not exactly make one keen to take a bath.

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PhD position on seaweed farming in Sweden

The Department of Biological and Environmental Sciences at Gothenburg University announces a PhD-position on macroalgae farming. The lucky winner will be located at Tjärnö Marinebiological Laboratory, just south of Strömstad on the Swedish west coast. It sounds like really interesting stuff!

Tjärnö Station as seen from r/v Nereus

Tjärnö Station as seen from r/v Nereus

Type of employment: Fixed-term employment, four years
Extent: 100 %
Location: Department of Biological and Environmental Sciences, Tjärnö, on the Swedish west coast.
First day of employment: Up on agreement
Reference number: UR 2014/914

Doctoral education
The admission to doctoral education takes place in natural science, specialising in biology. The program comprises four years of fulltime study and includes three years working on a thesis project and one year of courses and literature studies. Courses can be selected within the department/faculty, but national/international courses can also be included. Teaching and supervision of undergraduate students may be included, which extends the doctoral education period.

Project description
The PhD project is part of the larger research project “Sustainable large-scale cultivation of seaweeds in Sweden” where researchers from the University of Gothenburg, the KTH Royal Institute of Technology, and the Scottish Association of Marine Science participate. The overall project objective is to develop a sustainable large-scale system for growing kelp (Saccharina latissima) at the Swedish west coast. Seaweed cultivation is the fastest growing aquaculture sector globally, but is totally undeveloped in Sweden despite good natural conditions. The project deals with methodological and environmental aspects such as new cultivation techniques, mass production of spores and seedlings, breeding of crop varieties, and effects of seaweed cultivation on the surrounding marine ecosystem.

Saccharina latissima

Saccharina latissima

Job assignments
The main task is to carry out thesis work under supervision, during which the PhD student will develop knowledge and skills in methodology, analytical ability and subject theory. The work tasks include laboratory-based production of seedlings, development of new cultivation techniques for seaweeds in the field, development of high-performing lines through breeding, and evaluation of positive and negative environmental effects of large-scale algal cultivation. The studies will be conducted both in the field and in the laboratory.
The thesis work also includes statistical analyses and compilation of results in scientific papers, leading to the publication of a doctoral thesis. The PhD student will also present results at conferences, seminars, and project meetings and is expected to communicate and collaborate actively with other participants.

Small seedlings of Saccharina latissima on rope.

Small seedlings of Saccharina latissima on rope.

The admission to doctoral education takes place in Natural Science, specialising in Biology. The program comprises four years of fulltime study and includes three years working on a thesis project and one year of courses and literature studies. Courses can be selected within the department/faculty, but national/international courses can also be included. Teaching and supervision of undergraduate students may be included, which extends the doctoral education period.

For more information on the position, check THIS LINK

You can also contact
Henrik Pavia, +46(0)31-7869685, henrik.pavia@bioenv.gu.se
or
Head of department: Ingela Dahllöf, +46 (0)31 786 3393, ingela.dahllof@bioenv.gu.se

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Roskilde revisited

Well, here we go!
After leaving the experiment with fragments (see previous post) in the basement at Roskilde University over Christmas and New Year, it was finally time to go back and see if any of the small fragments of ( Fucus radicans ) has been well behaved ande done what we want them to.

There can be MANY fragments on just one ramete of Fucus radicans

There can be MANY fragments on just one ramete of Fucus radicans

A quick refresher of the experimental background and purpose:
In the ​​Bothnian Sea, the brown macroalgae Fucus radicans has been shown to be up to 80% clonal, something that is unique among seaweed belonging to the Fucus – family.
However, it is not unusual for algae to adapt with a more clonal life cycle in brackish environments (salinity between 2-15 parts per thousand) because their sexual reproduction requires the sodium ions (NaCl – sodium chloride) from salt to work (see post about this here).

When it was discovered that Fucus radicans was clonal , it could also be described as a separate species. It was previously thought that it was a dwarf morph of Fucus vesiculosus, which is the dominant macroalgae in the Baltic Sea.

In order to reproduce clonally, fragments from one individual falls off from the parent plant and then attaches to the bottom again. But under what circumstances does this happen? What are the most favourable conditions for the fragments to re-attach? Should it be on hot summer days or cold winter nights?

Once we know this, we can understand more about when Fucus radicans is most sensitive to disturbances in the form of e.g. chemical emissions, eutrophication or construction work that affects the aquatic environment. We hope that our experiment can help to provide a better basis for management decisions concerning the Baltic Sea’s unique and fragile environment.

So, how did we set up our experiment?

We collected fragments from several plants of seaweed from different sites. Since we can neither afford nor have the time to run genetic tests on them to see that they are not all the same individual, which of course can happen when working with a species that is clonal, we made sure to get both males and females. For a longer story on startup, read the post on our startup HERE.

But on this trip it was time for me and my colleague Tiina Salo to do our first reading of the experiment.

Research is largely a matter of daring to fail, over and over again. The pile of rejected hypotheses about how one thought it might be is growing rapidly. Guess if we were surprised when our experiment had not only managed to run the whole time period without the electricity shorting out completely (except for some problems in the beginning that Tiina solved). We had results!

Two amazed PhD students could not believe their eyes.

So after checking all 96 replicates with four small fragments in each jar, I took out the bag with Fucus radicans that I had taken with me from Stockholm and we began to sort 384 new fragments into the jars for another round.

Fragments, fragments, fragments...

Fragments, fragments, fragments…

In the evening, I saw fragments when I closed my eyes.

Now, the second round is getting on and there will be a trip down again for me in early February to finish it, and hopefully get the same result as in our first round. You never know when it comes to seaweed, so keep your fingers crossed.

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Fragment experiment started in Roskilde, Denmark

At the end of November, I spent a week at Roskilde University in Denmark.
By invitation from fellow marine botanist professor Morten Foldager Pedersen, I went there to start up an experiment on Fucus radicans together with his PhD-student Tiina Salo.

Fucus radicans is named after its ability to reproduce asexually by fragmentation. Radicans is latin for “root-forming”, and although algae do not have roots, they form root-like attachments to the substrate, called rhizoids. So, when a small fragment falls off the mother algae, it can re-attach and form a new thallus, which is a genetically exact copy of its “mother”, i.e a clone.

A fragment of Fucus radicans has formed new rhizoids, attaching to the bottom of a petri dish.

A fragment of Fucus radicans has formed new rhizoids, attaching to the bottom of a petri dish.

To reproduce in this way is not very common within the Fucus-family. We do not know what favours this mode of reproduction, unlike the sexual reproduction where we know that salinity plays a major role, but light and temperature is also important.

So, in order to find out how Fucus radicans has the best non-sexual reproduction, we designed the experiment in Roskilde.

The parameters we have decided to try are light, temperature and water movement.

Together with Tiina, I spent the better part of the week in the basement of the Biology department, in a temperate chamber filled with algae, sea urchins, a hard-at-work master student and the all-time favourite combination of electricity and water.

The light box is fitted over one of our white tanks.

The light box is fitted over one of our white tanks.

In order to decide if any of our tested parameters, alone or in any combination, contributes to the formation of rhizoids, you have to plan the setup so that the results can be testad statistically. This means that you have to think hard before you start the experiment, so that you can use the data to actually answer your initial question. I’m in luck. Tiina is a total wiz when it comes to statistics, and two heads are better than one.

To the right can be seen the heater (square box) and the cooler (spiral).

To the right can be seen the heater (square box) and the cooler (spiral).

I had brought some Fucus radicans from some different localities with me to Roskilde. We picked off small fragments, no bigger than 1 cm, and placed them on tiles. Tiina bought them at Bauhaus and had had the same experience as me. Why is it considered strange to be more interested in the back of a tile?

Four small fragments on a tile.

Four small fragments on a tile.

Finally, we were all set and could switch on the electricity again. We’ll leave it for approximately seven weeks, then I’ll go back and check the result. Meanwhile, wee keep our fingers crossed, hoping that the seaweed will cooperate and form nice new rhizoids. We’ll keep you updated.

It is fun to work with seaweed!

It is fun to work with seaweed!

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Autumn preparations at Askö Laboratory

Last Monday it was time to put the seaweed out in the sea for overwintering. After some different trials of overwintering indoors in the Experiment Hall at the Askö Laboratory, with extra lights and air pumps, we have found that it is still difficult to get good enough water circulation and movement for the seaweed to be happy. It becomes brittle and falls apart come spring. But tying plants on to net cages and placing them on the sea floor at some meters depth works just fine!
The weather was amazing. Calm and brilliant sun. But the water level was too high, so now they are places too shallow to remain in the bay all winter. We will have to come back later and move them to a deeper waters. That will be a dry suit -job.

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In this year’s seaweed plantation is material from Gotland that we have collected in order to try and solve the question of if there is a third ecotype of bladderwrack. We know from before that in the Baltic Sea we find both summer reproducing (end of May-June) and autumn reproducing (end July-October) bladderwrack. But now it seems that we have found a third type, that reproduces more or less constantly throughout the entire season (May-October).

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The Sea Environment Seminar of 2013, was held at Vår Gård located in Saltsjöbaden outside Stockholm. In the morning Lena went for a walk alongthe beach and found plenty of free-floating bladderwrack balls, both in the wrack wall on the beach and also floating in the shallow water, rolling around.

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According to litterature, these do not reproduce sexually, and we have never seen any reproductive tips on this form of bladderwrack. Naturally, she collected several wrackballs. Since Lena had forgotten to bring a plastic bag (wich is something a true marine biologist always should keep on her/him), she had to go back to the hotel reception and ask for one. Imagine their surprised looks. The day after, Lena went out to ASkö and tied the wrackballs to little ceramic tiles. What we are looking for is if these freee floating forms will become sexual in spring if they have a fixed up and down. Now they are placed in the sea for the winter, and all we can do is wait for the return of sunlight and warmth in spring, when we can dive down and check if there are any reproductive tips on them.

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Day 5 EMBS – The final sprint

It’s not fun to get the presentation slot first out on the morning after the conference dinner. But Katarina from Estonia got a good attendance and gave an interesting presentation on the zebra mussel (Dreissena polymorpha) and its impact on the ecosystem of the heavily eutrophicated Pärnu Bay in southern Estonia.

Maillie Gall from Australia told A story of two sea urchins, in which she compared the population genetics of the two sea urchin species Heliocidaris erythrogramma and Heliocidaris tuberculata to see how far their larvae spreads. She has primarily examined whether the duration of the planktonic larval stage plays a role for the spreading distance. It was very nice to rest those weary eyes on some beautiful pictures of sea urchins and Australian waters.

Jennifer Loxton held one of the conference’s coolest presentations, according to me. She showed how a bryozoan (phylum Bryozoa, it’s an animal) that came into English waters recently from Japan, reproduce like crazy. With movies and beautiful microscope images, we see that most of the currently known bryozoans form one egg bump per individual, where a larva is formed which then swims away and form a new colony. The Japanese moss animal produces up to five bumps, simultaneously! Unbelievable. The animal is red in color and thrives in cold water with high salinity, so we’ll probably not see it at the Swedish coast.

Final speaker of the conference was Paul Somerfield from Plymouth Marine Laboratory, renowned marine biologist and statistician, who talked about how to use statistics and not place too much weight on that which is odd or rare if one wants to describe an overall pattern. The presentation was entitled “Putting the species back into community analysis “. Funny, easy to understand and relevant!

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Day 4 EMBS Galway

Niall McDonough from European Marine Board started the day. European Marine Board is a partnership of 35 national marine / oceanographic research institutes from 20 European countries. Recently, it has also opened up for a membership of a consortium of universities. The Board is working as a platform to develop a common understanding of what is needed and what should be prioritized within marine research in Europe, and communicate this to policy makers in the EU. There are lots of interesting publications that can be download for free on their website http://www.marineboard.eu
For those who want to learn more about the sea, they are also running a project called Ocean Literacy, wich we will look into more closely and get back to you on.

Brenda Walles from the Netherlands present us with more information about oysters, wich we like a lot, especially with garlic. She has further investigated the possibilities of using oyster beds as erosion protection (bioengineers) on exposed coasts. Today, they are used mostly as breakwaters, but they also have a greater impact on sediment bottoms around them. The most important factor for optimum protection has proven to be the length of the reef, not surprisingly, but the oysters also have more beneficial bioengineering effects that could be utilized better than we do today. And they are so very tasty…

Katrin Bohn from Southampton University has participated in a study of re-colonization of old boat docks in Liverpool that were restored in the early 1980’s. The study was begun several years ago by Professor Stephen J. Hawkins. The restoration wincluded removing large amounts of accumulated sediment in the docks and putting back the gates in order to control the water flow. The water clarity and the oxygen concentration in the dock improved significantly during the first six years, and now mussels, sponges and sea squirts have moved in.

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Field season in full bloom

The days are just soaring by as the field season hits its high peak.

Helping us in this organized chaos is Frances Ratcliffe, volonteering marine biology student from UK. It’s such a help to have an extra pair of hands. We are very glad to have her with us.

Frances and bladderwrack!

Frances and bladderwrack!

The week before last was spent at the Askö laboratory, were we ran the Baltic Sea part of a two-station experiment wich will look closer on the effects of grazing snails on seaweed.

First, we put the seaweed (Fucus vesiculosus and Fucus radicans) grow a while without any grazers, in order to get undamaged tissue.

Seaweed growing

Seaweed growing

After a couple of weeks, we placed the tips in jars with gastropods (marine snails) and let them graze for a couple of days. We so hope that they were hugry and ate a lot, so that we can see the grazing damage under the microscope later on.

45 jars with gastropods and an even flow of water. Amazing what you can build with a pipe and some hose.

45 jars with gastropods and an even flow of water. Amazing what you can build with a pipe and some hose.

Once the seaweed was grazed, we collected some Ulva intestinalis, a green algae, and made it release its spores.

<img src="http://tangbloggen.files.wordpress.com/2013/07/entero1.jpg?w=300" alt="Ulva intestinalis spores makes the water go green.” width=”300″ height=”224″ class=”size-medium wp-image-910″ /> Ulva intestinalis spores makes the water go green.

What we hope to see is if the spores will be able to grow on the grazed surface of the seaweed.

<img src="http://tangbloggen.files.wordpress.com/2013/07/sdd201.jpg?w=300" alt="We have seeded the grazed seaweed by poruing spores of Ulva intestinalis in the water” width=”300″ height=”224″ class=”size-medium wp-image-920″ /> We have seeded the grazed seaweed by poruing spores of Ulva intestinalis in the water.

Let’s keep our fingers crossed and hope that it grows!

The week that was and this week, is spent at Tjärnö laboratory on the other side of Sweden, were we are running the same experiment, but in saltier water and with Ascophyllum nodosum instead of Fucus radicans and with other gastropods.

Our lives have been made so much easier thanks to Marit, who is doing her master thesis together with us. She has tended to our experiment so that we didn’t have to go back and forth between the coasts like crazy. Thank you Marit!
Meanwhile, she has also done an enormous fieldwork on a very interesting study on gastropods and seaweed, that we hope to write more about here on the BalticSeaWeedBlog.

Marit shows her disected gastropods.

Marit shows her disected gastropods.

it is always nice to meet and talk about seaweed. We had many nice discussions on this fascinating topic.

Frances, Marit and Lena discuss seaweed at Tjärnö Laboratory.

Frances, Marit and Lena discuss seaweed at Tjärnö Laboratory.

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Seaweed on the rocks

It is SUCH an advantage to have access to an ice breaking ship when one works with seaweed.
Mid-March is unfortunately not always full of sun, birdsong and warm spring temperatures.
On March 18th, we wrwe out at the Askö laboratory to do a reading of some experiments that have been out in the sea over winter.

Havet the door

With a lilttle help from the ice breaking R/V AURELIA and skipper Eddie, I could reach one of the sites, located just south of the boathouse.

The seaweed has not suffered from the cold winter, but was in good shape. When I lifted the “weedbeds” up onto the ice, lots and lots of animals swam out. Small crustaceans, gastropods and caddis worms a plenty, all of them have spent the winter in the seaweed.

Tång o is

Allthough the visibility in the water is very good this time of year, and the temperature is, well, shall we say refreshing, I can’t help but longing for summer. It is quite a struggle to move large sheets of ice when one is i the water…

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Into the deep

Here is a clip from the “seaweed-bed” at the Askö laboratory, where most of our experiments are going on. This was filmed in january 2012, with the purpose of checking on the bed, change light/temperature sensor and collect some plates for measure of juvenile growth.

The bed holds about 60 ceramic tiles, onto which we have “sown” bladderwrack and some other wrack crosses. We use the non-glazed side of the tiles since it is important that the surface is porous enough for the seaweed eggs to attach. This makes for some interesting conversations when we buy tiles!