The expedition for monitoring of the ecological state of Lake Baikal ended in September. It was organized by En + Group together with the Lomonosov Moscow State University and was aimed at determining the actual risks and threats to the lake created by anthropogenic load, technology-related factor and natural processes. The results of the expedition were summed up by its leader, Candidate of Biological Sciences, Senior Researcher at the Department of Hydrobiology of Moscow State University, Mikhail Kolobov.
Key to Baikal: The expedition was to be held from August 15 to September 1. Have you met the deadline?
Mikhail Kolobov: “The weather has made adjustments, so the expedition lasted a little longer. There were heavy rains on Lake Baikal, and we had to wait until they stop. Going to open water on a boat was rather dangerous, the hydrochemical background of the lake was blurred, and it was impossible to reach some places due to the overflow of rivers. Therefore, we were one week behind the schedule, so we had to literally “be on the hook”, waiting for the right weather”.
Key to Baikal: Did everyone come back in good health, were there any incidents, diseases, excesses or force majeure circumstances?
“Absolutely, we have been all right. We are really lucky. We returned without any losses, injuries or incidents. The expedition went well, and we are satisfied with the results of fieldwork. We have accomplished everything we planned, even with a small margin for the future”.
Key to Baikal: How many people went on an expedition and who were they?
“A total of 15 experts participated in the expedition this year. Of course, not all of them were present simultaneously: people came and went, each of them had a specific work task. The majority of the coming scientists represented Moscow State University: hydrobiologists, ecologists, biogeographers. There were students and post-graduate students, including from Irkutsk University. The representatives of the Siberian Federal University were also there. Our colleagues studied the nutrition of the spirogyra algae that is now actively propagating in the coastal zone of Lake Baikal. The employees of the Kharkevich Institute for Information Transmission Problems of RAS were also participating. Each of them had a clear research area; some of the samples were taken for our colleagues who did not manage go to Lake Baikal. Thus, even more experts will join the work at the stage of processing the material collected by us”.
Key to Baikal: Can you define the global goal of the expedition?
“First of all, it is an assessment of the state of the coastal ecosystem of Lake Baikal and the accumulation of relevant data. Various tasks were performed for this purpose. A lot of attention was paid to hydrochemical analysis. The content of various substances in water at different depths was determined. Depending on the concentration of these substances, we can assume what processes are currently taking place in the lake. First of all, this is related to the nutrients needed for the life of organisms - nitrates, nitrites, phosphates, trace elements. We also determined hydrophysical characteristics of water - temperature, acidity, total salt content and oxygen content... All these indicators can tell us about the state of the Baikal ecosystem. Besides, we took samples for determining the content of heavy metals.
Key to Baikal: What does their content in water show?
“Heavy metals (for example, iron, copper and zinc), on the one hand, are substances necessary for the life of aquatic organisms, on the other hand, their high concentrations may cause intoxication and lead to the death of aquatic organisms, especially small animals such as crustaceans, insects and mollusks - the basis of the food chain, and have a destructive impact on the entire ecosystem. Mercury and lead are even more powerful toxic agents. An increase in their concentrations in the water indicates an increase in their washout from the land, for example, as a result of coastal destruction, soil erosion, fires, mining or activities of industrial enterprises.
Key to Baikal: What about the infamous spirogyra?
“Spirogyra deserves a special thanks. This is a real indicator of troubles of the Baikal ecosystem, which shows us the places where something is wrong. If we see active growth of spirogyra, then the ecosystem is under a strong impact. This usually is local eutrophication, that means, saturation of the environment with biogenic elements, as well as water heating.
Two elements are very important for plant growth: nitrogen and phosphorus. They are the basis for the growth of living cells. Therefore, we studied the content of these substances in the water of the lake. Phosphates are also the components of washing powders. In case of uncontrolled use, large quantities of these powders get into the water of the lake, and algae begin to actively consume them. First of all, this is manifested in the snowballing growth of spirogyra. Any plants use the same substances for growth, but spirogyra consumes them more actively than others. The alga can very quickly increase its biomass under favorable conditions.
As for the nitrogen compounds, we wanted to understand how they entered the water - from the surface or, maybe with groundwater… With the use of isotope analysis, we are trying to determine the ways they enter the lake ecosystem”.
Key to Baikal: Were you only interested in spirogyra among all flora and fauna?
“No, we also studied the Baikal sponge - Lubomirskia baicalensis. This is an endemic of Lake Baikal. It is an active filter-feeding organism, and previously the representatives of the species in the lake were numerous. A small sponge with the size of 7-8 cm passes tens of liters of water per day through itself. Since 2011, a disease of the Baikal sponge has been observed in the lake: it leads to necrosis and destruction of the tissues of the sponges, followed by the death of their colonies on vast territories. It is not yet clear why this happens. Now it is impossible to say unambiguously whether people are to blame or it is a natural process - a bacterial invasion or a catastrophic reaction to the changes in environmental conditions”.
Key to Baikal: Please, tell us in more detail why you devoted so much time to the problem of microplastics.
“This problem is relevant all over the world. The main advantage and the main disadvantage of most types of plastic is that they are very durable. Bags, bottles, packaging, synthetic fabric for clothes... Polyethylene, polypropylene, polystyrene, polyvinyl chloride, acryl... Over the past half century, the mankind has produced more than 8 billion tons of various products from different types of plastic. 5 billion tons of it is already located in landfills or in the environment. Large amounts of of plastic produced by people eventually get into the oceans, lakes, rivers. This volume is measured in tens of millions of tons per year.
As of today, there are no places on our planet without recorded plastic pollution. Baikal is no exception. As plastic gets in the environment, it begins to change ecosystems, interacts with living organisms, at the same time decaying and decomposing.
Microplastics are a result of destruction of plastic products. Under the influence of mechanical abrasion or ultraviolet radiation, living organisms or other factors of the natural environment, plastic disintegrates into the smallest particles - microplastics. The sources of microplastics are also cosmetics, toothpastes, scrubs that initially contain the smallest plastic particles. According to the definition of “microplastics” refers to plastic particles with the size ranging from five millimeters to one thousandth of a millimeter.
The danger of microplastics towards individual living organisms and ecosystems in general are still actively discussed. Undoubtedly, a dangerous feature of plastic microparticles is the ability to accumulate many toxic substances and transport them. Another harmful feature of microplastics is the fact that when the substance is overgrown with microalgae and a bacterial film, it cannot be distinguished from natural food particles. Living organisms eat these particles, as a result, non-digestible microplastics accumulate in their intestines. These particles, once swallowed, can damage the internal organs of animals and release dangerous chemicals - from hormone-disrupting bisphenol A to pesticides. This influence also violates the protective functions of the body, as well as stops the growth and reproduction of cells”.
Key to Baikal: What animals can become victims of microplastics?
“The smallest ones suffer most of all. These are zooplankton organisms, small bottom crustaceans, molluscs, fish fry, that is, the animals making up the basis of the food chain of the entire Baikal ecosystem. Bigger organisms, in turn, feed on them. It is clear that in case the basis is troubled, the entire chain of interconnected organisms suffers. As a result, the ecosystem can unpredictably change under the influence of accumulation of the mass of microplastics therein.
Key to Baikal: Research works have been carried out since 2016. In which way are they different from the expedition?
“The first research was performed for a preliminary assessment of the environmental situation. We needed to form our own opinion, to determine the working methods that would be most convenient for us. We estimated the things that needed close attention first of all. We studied the content of microplastics at some points of the lake. Now the territorial scope of microplastics samples taken is much wider. The same applies to hydrochemical studies. The use of portable spectrophotometers and other portable devices enabled us to carry out some of the analytical work directly on the coast, which significantly increases the accuracy and reliability of the results. We took a larger number of samples near settlements this year, as compared to previous years, which allows us to form a more detailed ecological pattern. Based on the experience of previous studies, new tools and research methods have been developed, for example, nets for collecting microplastics. This year we also used the equipment for underwater and aerial photography, which enabled us to conduct exploratory surveys of the places for research much more quickly. The use of a greater variety of water and land transport has given us the opportunity to become more mobile and cover the greater area of the lake during a shorter period of time”.
Key to Baikal: In which places were the studies conducted and why were they chosen?
“We tried to cover a maximum area of the coast of Lake Baikal, giving preference to inhabited settlements as the main possible sources of pollution. These are the settlements of Maksimikha, Gremyachinsk, Babushkin, Posolskoye, Tankhoi, Vydrino, Baikalsk, Slyudyanka, Kultuk, Listvyanka, Bolshoye Goloustnoye, Khuzhir. We took samples along the entire perimeter of the Selenga delta.
The amount and composition of substances released can vary greatly in different inhabited settlements. This is influenced by a combination of many factors: such as the number of people, the area of a settlement and its distance from the coastline, terrain, industrial enterprises located nearby, river flow, etc. Selenga is the main source of a great variety of substances entering Baikal, collected from a huge catchment basin with the area exceeding that of France. The river carries a wide range of pollution: organic and mineral substances, including heavy metals, industrial and household wastewater”.
Key to Baikal: What practical results can the expedition bring and when will we get to know about them?
“The first results have already been obtained. The samples that required immediate hydrochemical analysis were processed in the field. First of all, this concerned determining the concentration of nutrients: compounds of nitrogen, phosphorus, and concentrations of surface active agents. As I already noted, we brought all the necessary equipment and analysis reagents with us. Some of the samples were sent to the laboratory and will be processed in the nearest future, after which we will conduct the analysis to identify patterns of spatial distribution of various substances in the waters of Lake Baikal. Some samples will be studied even longer, since this process a meticulous and time consuming. However, we are planning to obtain very important information. Even today, it is not completely clear what precisely is happening with the ecosystem of the lake, and our results will allow us to shed the light at the current situation, to identify the main threats and sources of pollution. In a long run, this will make it possible to develop mechanisms for controlling and regulating human economic activities on Lake Baikal. Economic development of the Baikal territories is inevitable and indispensable. Many people live and a large number of enterprises function there. In this regard, it is necessary to find development options that will make the maximum protection of the fragile Baikal ecosystem possible.
Much attention has recently been paid to it. It emerged that a lot of environmental problems have accumulated over the past decades; previously people had not a slightest idea about them or considered them insignificant. They are accumulating at a swift rate. If you pay no attention to them, this can lead to the extinction of many species of animals and plants and the destruction of the lake’s ecosystem. We chose to study the Baikal sponge for a good reason: it is the endemic of Lake Baikal. Endemic species originated under the conditions of the unique ecosystem of the lake and have existed here for millions of years. Therefore, they are the most sensitive to environmental changes. If the conditions for the existence of an endemic species change significantly, its number in the habitat is consistently declining. We have no source to replenish it from”.
Key to Baikal: What happens if it disappears completely?
“If there is a gap, something will fill it. It will be replaced by other species of animals or plants, ordinary ones, the ones we have everywhere. The uniqueness of Lake Baikal lies in the fact that about one thousand endemic species live in it. If they begin to be replaced by ordinary flora and fauna, it will be a tragedy.
I would like to notice that we plan to accumulate the relevant data on the ecosystem of the lake on the basis of long-term observations. As a result, we will see the dynamics. Of course, we will not be able to boil the ocean and explore all the existing problems. To obtain a reliable assessment of the ecological situation on Lake Baikal, we need the joint work of many experts in various fields over a long period of time. We want to use the results of our work to complement the already existing picture of studies on the largest freshwater lake on the planet. Given today's environmental and economic conditions, this is timely and crucial”.