Until now, scientists believed that the increase in carbon dioxide in the atmosphere accelerates the growth of forests, and as a result they begin to absorb more carbon dioxide. In this illusion, it seems, will have to leave.
Do not be on this planet of forests and oceans, the amount of carbon dioxide in the atmosphere would have been much higher than today. Approximately half of all anthropogenic carbon dioxide emissions that is, those that come from industry, transport, energy, agriculture and other human activities, from year to year and is absorbed by the seas of the terrestrial biosphere. And on land — especially, of course, natural forests, which are sometimes referred to as high-flown "green lungs of the planet."
One of the important process of forgotten
For photosynthesis (the process by which the oxygen) trees need carbon dioxide. Growth in carbon dioxide in the atmosphere contributes to the growth of trees, it is for them a kind of additional fertilizer. All true, but that's what the output of that? "If the amount of CO2 in the atmosphere will continue to increase, it is, many hope, will lead to the growth of forests, which in turn will help the biosphere to absorb more CO2 — Bugman says Harald (Harald Bugmann), professor of the Swiss Technical College in Zurich, a specialist in forest ecology. — In other words, these people believe that the very growth of carbon dioxide emissions will enable us to cope with the growth of carbon dioxide emissions. "
Of course, it would be wonderful. Moreover, that carbon dioxide fertilization does have an impact on the vegetation — it is not in doubt. Satellites are visible regions with forests thrive, absorbing more and more carbon dioxide. That's just the effect can be very short-lived — warns scientist: "I have performed studies indicate that in our calculations and estimates, we forgot to consider one important process that can greatly reduce or even completely eliminate the biosphere as a function of carbon uptake of gas. "
The faster the growth, the lower timber
The process, which speaks and writes in his scientific papers Swiss environmentalist — is the premature aging of trees. Increased growth leads to a reduction in life expectancy. "This is due to the fact that the trees growing in the atmosphere, supersaturated with carbon dioxide, reducing the quality of the wood, — the professor explains. — Accordingly, they are worse resist disease, pests, extreme weather events, and die sooner. This was accumulated carbon dioxide rapidly released back into the atmosphere. "
At least that's how it looks in the computer calculations of Zurich scientist. Professor Bugman modeled processes in six different forest types typical of Switzerland, under the influence of carbon dioxide fertilization and accelerated growth of 10-30 per cent. Results of this study is quite representative of all natural forests in Europe — the scientists' current estimate of experts based on the assumption that there is no fast dying forests not. Moreover, it is natural, it turns out that trees accumulate more and more carbon dioxide. And my Evidence suggests that the forests will die sooner. And if so, we will get what in mathematics is called a zero-sum game. So fertilizing carbon dioxide in the beginning of the cycle the cycle will not give us absolutely nothing. "
If the model can not be verified, it is better to be safe
Calculations Swiss researchers attracted interest from colleagues. American environmentalist Hank Shugart (Hank Shugart), professor of the University of Virginia in Charlottesville, said: "I must say that my work is confirmed by a number of his findings. About that in artificial forest plantations and rapid growth means a quick death, we knew a long time. This effect due to the fact that the trees are more tightly competing with each other. research professor Bugmana enriches our knowledge in this area: it shows that a similar effect occurs in natural forests. That is where the magnitude of the absorption of carbon dioxide from the atmosphere more large — for example, in tropical rain forests of the Amazon. "
However, the professor Bugman admits that his model, there is one very significant drawback: it is virtually impossible to verify. Because in order to find out if obtained with the help of the calculated data to be reliable, it is necessary to follow the life cycle of at least one generation of trees — from the beginning to the (perhaps premature) end. Such an experiment is hardly possible: it would last for centuries. In this situation, the recipe can be one — caution and prudence — Swiss ecologist says: "On the horizon, a factor seen. There is reason to believe that it really exists. And acts to cancel the additional absorption of CO2 biosphere on which we all hoped . So, do not have any illusions, it is better to be safe. no need to rely on this additional absorption, when it comes to, say, the quota of greenhouse gases and the international commitments to reduce their emissions. So in this case there is a political component ".
Author: Vladimir Fradkin
Editor: Yefim Schumann