August 1, 2017

Scientists of Klaipėda University Seek to Establish the Factors Causing the Curonian Lagoon Bloom

Do you happen to know that it is the Curonian Lagoon that is to be blamed for the water bloom in the Baltic Sea coastal strip? It turns out that the blooming water outflowing from the lagoon colours the coastal strip of the Baltic Sea where the holidaymakers like to swim. That was argued by assoc. prof. dr. Mindaugas Žilius, leader of a Klaipėda University biogeochemists’ group and of a new NitFix project, won in the competition for young researchers held by the Research Council of Lithuania. The researchers of the Marine Science and Technology Centre and the Open Access Centre for Marine Research of Klaipėda University, in cooperation with scientists of the Vilnius University Institute of Biochemistry and Stockholm University (Sweden), will study the importance of the “the gardens of mysterious microorganism communities”, thriving in the Curonian Lagoon water column, for the dissolved atmospheric nitrogens fixation in water. They will try to understand how it affects pelagic ecosystem functioning of the Curonian Lagoon, what predetermines the bloom, and how it changes the inflow (or loads?) of nitrogen as a nutrient into the Baltic Sea

The NitFix project features methods applied in Lithuania for the first time

The Curonian Lagoon is the largest lagoon in Europe, situated between the mainland and the Baltic Sea. The water mainly gets there from Lithuanian and Belarusian territories together with precipitation, waste water, and fertilisers washed from agricultural lands. “During the cold season, the Curonian Lagoon functions as a filter that treats the Nemunas water before it gets to the Baltic Sea and thus prevents it from becoming more polluted. However, in the summer, we notice that everything is happening the other way around: the amount of the Nemunas flow is reduced, there is less rain, and the water in the lagoon is blooming much more intensely”, said dr. Žilius. As observed during the research of the biogeochemists’ group, in the summer the cyanobacteria causing the water bloom are able to uptake the dissolved dinitrogen (N2) from the atmosphere and to convert it into organic and non-organic compounds that support the growth of cyanobacteria and other algae. 

The research object in the NitFix project is the nitrogen fixation carried out by different microorganisms and its impact on the functioning of the Curonian Lagoon ecosystem. In that project, for the first time in the Curonian Lagoon, direct methods of measuring the rate of nitrogen transformation will be applied, as well as functional marker studies enabling the evaluation of the genetic fixation potential. The Curonian Lagoon will serve as a model to find out how the seasonal changes in the nitrogen content – from the nitrogen excess in the cold period to its shortage in the warm one – affect the activity of functional genes and how these changes in the ecosystem predetermine the introduction of new nitrogen into the ecosystem. During the project, based on the empirical data, the biogeochemical hydrodynamic model of the Curonian Lagoon will be improved, which will provide for actions contributing to the achievement of the nutrient reduction-related goals laid out in the Baltic Sea Action Plan.

Dr. Žilius, researcher of the KU biogeochemists’ group, together with his team won 100,000 euros for the project implementation. “In Lithuania, there is a lack of research on the amount of nitrogen in the Curonian Lagoon and on its sources, and nobody investigated the lagoon water by means of genetic methods. NitFix project will use direct measurements of N2 fixation, quantification of fixed nitrogen pathways and will apply functional marker gene analysis for estimating the genetic potential of N2 fixation for the first time in the water column of the Curonian lagoon. Moreover, during the project implementation, dedicated state-of-art methods will be used for the first time in shallow low-salinity estuaries. Therefore, project task and suggested methods or their combinations are unique and do not overlap neither with other currently implementing projects nor with any previous projects. In general, there are few universities in the world that apply such methods, and we learned them from Italian and German scientists”, said dr. Žilius

The project outcomes are significant for the general public and the Baltic Region

As stated by Žilius, researcher of KU and the leader of the NitFix project, the implementation of the project is of paramount importance. “Because we will apply new methods and look for new micro-organisms, the research may lead to important fundamental discoveries in the area of biogeochemistry.”

Since the Government of the Republic of Lithuania is committed to reducing the nitrogen inflow from the Nemunas River to the Baltic Sea by 30% , the reduction of pollution is relevant. “As soon as we find out the causes of the water bloom and know the scale of the nitrogen inflow into the Curonian Lagoon, we may be able to predict and regulate the process. Then we shall have cleaner water not only in the Curonian Lagoon, but also in the Baltic Sea. That will affect not merely holidaymakers, but also fish resources, as well as the Government funding for the prevention of environmental pollution”, informed dr. Žilius.

Presently, the team of researchers is in the stage of preparation, as the project will be launched on the 2nd of October and will end in mid-2020. “The next year will be devoted to intensive research, followed by the analysis of the obtained data”, said the project leader.

Grown up in Klaipėda University

Mindaugas Žilius studied in all the three study cycles, those of bachelor‘s, master‘s, and doctoral, in Klaipėda University: “I can say I grew up and became a researcher here “. The undergraduate and graduate studies of Ecology and Environmental Protection were different from doctoral studies during which Žilius undertook biogeochemical research. He had to face a number of challenges which demanded a lot of patience and time. “When I started the studies of biogeochemistry in Klaipėda University, we had almost no tools or analytical instruments. Today, after eight years of hard and intensive work, a group of young and ambitious researchers of biogeochemistry got together; we are increasingly getting recognised abroad, our research is gaining credibility; and we are building a huge complex of laboratories in the KU campus that will provide our group with incredible opportunities for further growth“, commented dr. Žilius.

The researcher is grateful to prof. dr. Marco Bartoli and dr. Gianmarco Giordani, scientists of the University of Parma in Italy, who became his good colleagues and friends. “They taught us the latest and most innovative methods, expanded our knowledge, and laid the foundation for biogeochemical research in Klaipėda University. Now we work together. Prof. dr Bartoli has for several years been working for Klaipėda University and making its name famous beyond the boundaries of Lithuania.” Dr. Žilius is happy to have doctoral student Irma Vybernaitė-Lubienė, dr. Jolita Petkuvienė, dr. Diana Vaičiūtė, and dr. Tomas Ruginis intensely working in the group. “Together we managed to carry out research in shallow estuarine systems in Italy, Germany, Poland, and Denmark.”

According to Žilius, biogeochemical research carried out in Klaipėda University has enormous potential: the scientists in Lithuania ignore it, although it is a very popular research area in the world. “That is applied research in which the classical and state-of-the-art methods are combined; in that way, any components of the environment, from a bacterium to an ecosystem, can be analysed. From a scientific perspective, that is an interesting and wide area: the very term of biogeochemistry contains three words: bio-, geo-, and chemistry. Those are processes and transformations taking place in the bottom sediments and the water column due to the microorganism activity and self-initiating reactions”, said dr. Mindaugas Žilius, biogeochemist of Klaipėda University.

Photo by Egidijus Jankauskas

Source: Klaipeda university