Trip to Vietnam – looking for seaweeds

When we landed in Hanoi we started with a meeting at MCD, Centre for Marinelife Conservation and Community Development, (more information to be found at http://www.mcdvietnam), where we got coffee and we had a first planning of the work for the following week.
välkomstmöte på MCD

MCD has been a partner to Stockholm University and the Department of Ecology, Environmental and Plant Science in Vietnam for many years. It is mainly women working at MCD and everything is very well-planned and efficient. During our visit we had the opportunity to meet with the local government in Phu Long and get information about the planning of aquaculture in the region for the future. Two master students will together with the help from MCD perform interview with local shrimp and fish farmers as well as trying to find out the use of trash fish in aquacultures, with the aim of proposing development improving the environmental conditions and integrated aquaculture.
Karta PHU Long areaMap of Phu Long

The next day we went to Cat Ba, to study different types of aquaculture activities, ranging from high to low intensity shrimp farming in mangrove plantations, where both fish mainly Tilapia are cultivated in combination with crabs and shrimps.
skylt vid odlingen

In the intensive shrimp cultivation 2-3 harvests are produced per year. This type of aquaculture takes up a much smaller area but has a strong impact on the environment while the extensive aquaculture takes up a 10 times larger area and has a less negative impact on the surrounding area and a lower but more diverse production.

hus på damm kantenThe family lives in the small house located on the edge of the pond.

Much of the island is part of a UNESCO World Heritage Site and the mangrove is 4000 ha protected. Between 1990- 2000, when aquaculture around the island peaked, 50 hectares of mangroves where cut down. The plan now is to replant mangroves and increasing area and cover.

Rhizophora
Mangrove plantering
Rhizophora utmed damm kant

The mangrove species planted are mainly Rhizophora and Avicennia. They are planted along both sides of the dam. The smallest plants are brand new and the largest over 2 meters in height are about 8 years old.

karta Lan Ha Bay

The second part of our trip was to visit Lan Ha Bay. The area is heavily influenced locally from farms, by untreated sewage from communities around the coast, from harbor construction and from runoff from the Red River, which transports large amounts of sediment, organic matter and nutrients. At the first farm we visited they were feeding the cultivated fish with thrash fish.

skräpfisk försäljning

skräpfisklådor till försäljning

Pictures of the on-going sale of trash fish and loading into boxes to be transported to neighbouring fish farms. At one of the fish farms you could stay and have a lunch with really fresh sea-food.

krabbor röda godaDelicious red crabs

Cultivation of seaweeds seems to be limited in Vietnam. On the road from Phu Long to Cat Ba I suddenly saw some red algae put out to dry along the small road. The algae had been collected form an adjacent pond where they grow naturally. They will get about 1 dollar for 10 kilos or one sac of dried algae (about 70000VDN). It may not be much money, but can still be a contribution to the salary which is around 200 -300 dollar/month.

samla torkade rödalger
rödalgskördRed algae harvest
The picture shows women who rakes up dried red algae and put them in sacks so that they can be transported and soled. My first guess on the species was Gracillaria, which I was able to confirm when I found some plants that were not dry.

Gracilaria spp.

Picture of Gracillaria spp. from the harvest of dried seaweeds photographed on a small plate at the hotel, since I had forgotten to pack paper for pressing seaweed!

During the visit to the fish farms, while the others were talking to the owner and investigated which fish were cultivated in the various cages and what they were fed, I lay on my knees and looked after what was growing on the edges of the cages and on the nets.
CladophoraCladophora
UlvaUlva

Here are some pictures of the findings! One Cladophora spp., one Ulva spp., looks just like our species on the west coast Ulva lactuca, one Bryopsis spp. and one Polysiphonia spp. The last two species were too small, so I was not able to take any photos.The algae were found only in the innermost fish farms, close to the coast and only down to about 0.5 m depth. Probably because the light conditions in water are so poor that the light is not enough for algal growth. Other species found on the cages were mainly different filter feeders, like sponges and hydroids.

Hydroid med symbiontisk rödalg

Beautiful red-coloured and finely branched hydroid, looking a bit like Dynamena or Abitenaria. The colour red is produced from a symbiontisk red algae that live inside the animal wall.

Svampdjur och ostron

Krabba i svampdjur

Those who had the most beautiful colours were different species of sponges, in colours of maroon, red or clear blue. In one of them was a small crab, who had found good protection inside the sponge. It has been a new experience and I have learned a lot of new things about Vietnam and would very much like to come back and learn more.

solnedgång Cat BaSunset over the bay – view from our hotel.

I will remember the travel to Vietnam for a long time during the dark winter months in Sweden and going to the Askö Laboratory studying the Baltic Fucus.

Advertisements

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

International Seaweed Symposium – Day 4

With rested brains, it is once more time to stock up on more seaweed, both mentally and physically.

All things sweet and seaweedy

All things sweet and seaweedy

After an opening plenary lecture by Iain Neish about the importance of having a vision and being stubborn if we are to succeed with aquaculture, it was time for a cup of coffee, a slice of fruit cake and the day’s first mini-symposium.

Plenary with Iain Neish

Plenary lecture with Iain Neish


Mini Symposium: Cultivation of tropical red seaweeds

The most common species of red seaweed that are farmed are Eucheuma spp., Kappaphycus spp., Porphyra spp. and Gracillaria spp.
In Chile and Peru, it is primarily Gracillaria spp. that is farmed. In Chile, they seek to develop new methods to cultivate seaweed in the lab, instead of taking material from wild populations as many do today. They have also investigated whether it is possible to grow other commercial species.

In Malaysia, the Philippines and Indonesia, most seaweed is farmed using the fixed off-bottom technique in shallow waters. The trick is to place them deep enough so that the algae are not harmed by the intense sun during low tide.

Most algae in shallow waters are farmed using the off-bottom method.

Most algae in shallow waters are farmed using the off-bottom method.

In deeper water, they use the free-swing method, where only one end is fixed at the bottom. The downside is that it takes up quite a lot of space, and then they must be set at such a distance that they do not become entangled in each other.

The free swing method, attached at only one point.

The free swing method, attached at only one point.

Other methods for deeper water is something called single longline rafts, spider web rafts or floating triangle, depending on how you have designed the ropes. But these rafts are secured at all four corners and thus are more stationary. It also means that you can place them closer together, without risking entanglement.

In deeper waters, single longline rafts are common.

In deeper waters, single longline rafts are common.

Some growers use hanging baskets that the seaweed is floating freely in, which does not seem like a good idea to me. But this is still at the development stage. They use high pressure water hoses to remove unwanted growth of other seaweed (epiphytes).

Dr. Flower Msuya from Tanzania showed a summary of how seaweed cultivation has started and continued for the East African coast, with examples from Mauritius, Madagascar, Tanzania and Zanzibar course. The main problem to cope with is that they are now beginning to get problems with various diseases. There is much further research to do and a lot of mistakes to learn from. At the same time, a mini-symposium was held in the hall next to this, with the topic being diseases and parasites on seaweed. It’s a hot topic for the seaweed industry.

Presentations: Integrated aquaculture and introductions
In Australia, much yellowtail kingfish and tuna are farmed. At present, there is no cultured seaweed in Australia, so the researchers are now trying to find species suitable for cultivation along with fish farms in order to reduce emissions (IMTA, see previous posts). The species they are looking for are those that are good at taking up nitrogen from fish farms, but there should also be a market for the seaweed.

Kathryn Wiltshire from the University of Adelaide tested several species of red and brown seaweed to see which was best at taking up nitrogen and which grew fastest, in order to select species suitable for further experiments with the conditions that give the best performance.

Tom Schils from the University of Guam (you get extra points if you know where it is without looking it up) told us that coral reefs in Micronesia and the Pacific have very distinct algal communities, which are now threatened by introducing new varieties of these species bred for cultivation. A well-known example is the red alga Acanthophra spicifera that has taken over shallow waters on coral reefs around Hawaii.

Micronesia has a Biosecurity Plan, which seeks to identify and prevent threats to the marine environment, such as how to manage ballast water which is a great disseminator of species from one place to another.

Dr. Yang from China showed how the farming of the red alga Gracillaria spp. is along China’s 18,000-kilometer coastline and how China is now working to develop the use of integrated aquaculture. Between 1967-1980, 50-60% of China’s aquaculture consisted of cultured seaweed, mainly brown alga Saccharina japonica. Since then, the proportion of farmed fish, shrimp, crabs and clams increased. It leads to increased nitrogen load, and you need to cultivate more seaweed to not have problems with eutrophication.
The production of Gracillaria spp. is rising steadily, from 0.13 hectares in 2000 to 1,067 hectares in 2007. In 2011, the total cultivation area of Gracillaria was an astonishing 1,500 hectares!