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Practically all natural sciences are now involved in the study of the global problem of the Earth's climate warming. In particular, this applies to the interaction of climatic changes and biosphere transformation processes. Since the latter are especially clearly manifested in the northern (boreal) part of the globe with over half of the world population, it is more appropriate to study these processes precisely here, in the opinion of Sergei Bartalev, Cand. Sc. (Technology), and Yevgeny Lupyan, Dr. Sc. (Technology) from the RAS Institute of Space Studies, the authors of an article for the Priroda journal.
Even brief periods of climatic fluctuations not only impact an ecosystem's productivity but also such factors as the probability of steppe and forest fires or proliferation of destructive insects. All this naturally has an indirect effect on man's economic activity. On the other hand, changes in economic systems affect the atmosphere and climate characteristics as well.
One can unravel this tangle of interdependences by computer analysis of orbital satellite observation data. Processing a vast amount of information calls for rather complicated automatic decoding methods so as to convert the endless columns of figures into geographic maps that not only look like an open book to specialists but are also comparable to those compiled 50 years ago and even earlier. As a result, such characteristics of vegetation are evaluated as its living forms (trees, undergrowth, grasses), types (coniferous, leafed), phenological dynamics (evergreen, deciduous), species composition as well as biophysical and biochemical characteristics (biomass, leaf surface area). All this information may be collected on a permanent and regular basis (satellite data for small-scale maps are supplied every day), to make it possible to accumulate time-related series of required characteristics.
The data thus obtained are used for calculating the amount of CO2 (basic hothouse gas) and also of energy flows in ecosystems, all this a basis for constructing climate change models.
Observation of the state and dynamics of ground systems with the help of orbital satellites allows us to solve large-scale problems. In Russia this work is carried out by the RAS Institute of Space Studies jointly with the RAS Center for Problems of Forest Ecology and Productivity and also by a number of other leading academic organizations jointly with West European partners, for instance, the Unified Research Center of the European Commission.
The map of Russia's ground ecosystems compiled by them offers a geographic picture of vegetation distribution. If you compare it with the map of forests in 1990, you will see that the basic coniferous forests of the country's European part, central Siberia and the Far East have been largely replaced by secondary forests that rose in the areas of intensive cutting and fires in the second half of the 20th century. On the other hand, the present-day map shows that uncultivated farmland in Central Russia is being increasingly overgrown with forests. All that allows us to assess the nature and intensity of economic activities affecting the surface albedo (reflecting capacity), temperature conditions, the amount and dynamics of moisture evaporation.
Monitoring of forest fires and their consequences, based on space data, makes it possible to assess the ecological and economic aftereffects of fires, and the amount of CO2 released into the atmosphere. Data supplied on a ten-day basis are an essential element of information support in compliance of this country's obligations under the Kyoto Protocol to the framework UN convention on climate change (1998).
Map of boreal ecosystems devastated by fires in 2000 - 2003.
The data on the dynamics of forest felling allow us to assess a major factor related to the anthropogenic effects on nature. Long-term changes in the area and condition of forests, largely in the taiga woodlands of European Russia, may be assessed with the help of large- and small-scale space photographs of key areas taken since the 1970s.
Finally, the series of photographs taken every day over many years make it possible to keep track of the area and dynamics of cultivated land use, monitor winter and spring crops, and crop rotation parameters. Methods tested in some of the regions of Russia's south may be extended to the entire grain belt. That will enable us, just as it is done in some Western countries, to determine the crop yield long before harvesting and analyze the condition of soils, among other things.
Evaluation of satellite data, together with methods for their study, allows us to create vast and regularly replenished databases accessible to a broad range of researchers. Such information is of great value for constructing climate models and for research into other aspects of interaction between ground vegetation and the Earth's climatic system.
Bartalev S. A., Lupyan Ye. A., "Space Monitoring of Boreal Ecosystems", PRIRODA, No. 9, 2005
Prepared by Andrei BIRYUKOV
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