Beginning in late autumn and then throughoutthe whole winter wood and shrubby flora of our land are in a state of rest. Such winter phenomena in plant life are caused by many reasons. Among them - a significant lowering of the temperature regime, lack of adequate nutrition and others. The life processes of plants are inhibited, and even under favorable conditions that have arisen suddenly, they can not resume. Many, probably, noticed that if in December-January to bring home a cut branch of a tree and put it in the water in the heat, then it does not "wake up", keeping its lifeless appearance. But if you already do this at the very end of winter, when the spring is approaching, the kidneys instantly dissolve, although it's still very cold outside. Why is this happening? What role does winter play in plant life? What makes the representatives of the flora in the wild and in the surrounding squares and parks wake up, scattering fresh foliage? We will try to answer these and other equally interesting questions in our article.
In hot countries that winter, that summer is the temperaturenot particularly "jumps" from the main average indicators. Therefore, trees in the subtropics and tropics grow and green throughout the year. The middle stripe of Russia is another matter, for example. Or Siberia. Here, the temperature fluctuations "plus-minus" sometimes make up breaks of fifty degrees, and this for many species of deciduous trees is simply disastrous. Wise nature invented for these foliage plants, protective responses to poor conditions of life, arising in the cold. Winter phenomena in the life of plants - a kind of "blockage" of life processes, helping to survive difficult times. What happens to them?
Winter phenomena in the life of plants causestate of rest, slowing metabolism inside the trunk. Apparent growth of trees is suspended. As well as the return to the atmosphere of moisture. Like nutrition with the help of the root system. No, in winter the trees, of course, also grow. Only they do it very slowly, imperceptibly for the human eye. Moisture also circulates (complete cessation of circulation, according to scientists, occurs at minus 18). In winter, a large tree evaporates in the air to 250 ml of moisture. But, you see, these processes are much slower than in spring and summer.
Almost all trees are discarded for winterfoliage (except for evergreen). It gradually turns yellow all autumn and falls off, leaving bare branches. These winter phenomena in the life of plants are also associated with the mechanisms of protection from cold: the plant loses the leaves and, as it were, is closed from the environment. Almost completely stops photosynthesis, a vital process for chlorophyll-containing leaves. The food becomes minimal, since the main portions of carbon dioxide are processed by foliage. And the root system, due to frost, reduces the supply of moisture and minerals from the soil.
We can say that the first signal for plantsis the reduction of daylight hours. When the light day is markedly shortened, the cells change the ratio between the substances responsible for the exchange and growth of tissues. The tree seems to be beginning to prepare for slowing down the life processes.
Such a state of deep winter dormancy,comparable to hibernation, in different species of trees and shrubs lasts differently. So, for example, at a birch or a poplar - till the end of January. A maple or linden spend in this state for up to six months (in especially cold winters). In the lilac, the hibernation period ends by December.
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